PREFACE  
In recent years, as China and other major countries in the world have successively put forward  
the development goal of carbon neutrality, the clean energy transition has attracted more and  
more attention from the world. The key to energy transition is to achieve “Two Replacements”.  
On the energy supply side, the proportion of renewable energy such as hydroenergy, wind  
energy, and solar energy is increasing continuously, but the randomness and fluctuation of  
renewable energy set a still higher demand for flexible adjustment of the energy system. On the  
energy consumption side, the trend of electrification is increasingly obvious. However, it is  
difficult to rely on electricity to directly meet the energy demand in aviation, navigation,  
industrial high-grade heating, chemical, and metallurgy fields, and it is also difficult to achieve  
the replacement of traditional fossil fuels by zero-carbon renewable energy. Therefore, new  
solutions are urgently needed.  
Hydrogen, as a clean, zero-carbon, efficient and sustainable energy carrier, provides an  
alternative solution for deepening the clean energy transition and fully achieving “Two  
Replacements”. At present, most hydrogen is produced by fossil fuels, and direct use of  
hydrogen as energy cannot achieve the goal of de-carbonization. Renewable energy such as  
wind energy and solar energy is used to produce green hydrogen to achieve the  
de-carbonization of the whole process from supply to consumption, so that the energy  
de-carbonization can be achieved by hydrogen energy.  
Green hydrogen comes from renewable energy. Green hydrogen is an important zero-carbon  
solution in the final energy consumption fields where it is difficult to directly use electricity. It  
becomes the link between renewable energy such as wind energy and solar energy and final  
energy consumption, to achieve indirect electricity replacement or even “non-energy  
application” of electricity, thus promoting comprehensive electrification on the energy  
consumption side. Compared with electricity, hydrogen is easier to be stored on a large scale.  
The mutual conversion of electricity and hydrogen will provide important long-term flexible  
adjustment capabilities for new power systems with renewable energy as the mainstay, to  
promote the development and consumption of renewable energy, thus facilitating clean  
replacement of energy supply. The close connection between electricity and hydrogen will  
become an important feature of the new energy system in the carbon neutrality scenario, and  
an interconnected modern energy network will be built in combination with various energy  
forms such as biomass energy, geothermal energy, and natural gas. Hydrogen energy is  
expected to become one of the important roles in the third energy transition, and it will be used  
II  
with electricity to achieve the clean, low-carbon and sustainable development of the future  
energy system.  
In this report, from the perspectives of demand, production, and allocation and in combination  
with different links in the hydrogen industry chain, the technical statuses of hydrogen  
application, hydrogen production, hydrogen storage, and hydrogen transportation are sorted  
out, the cost-effectiveness of different technical routes is compared, and the R&D directions of  
key technologies in the future are proposed. Based on the analysis of carbon neutrality energy  
scenarios and technology development trends, the scale of hydrogen energy demand in the  
future is judged. Based on the assessment results of clean energy resources, the potential and  
cost-effectiveness of green hydrogen production are studied. On this basis, an overall  
optimization analysis model for the electricity-hydrogen zero-carbon energy system is built,  
and the long-distance and large-scale hydrogen energy allocation scheme in China is  
proposed with the optimization goal of minimizing the energy consumption cost of the whole  
system in this report.  
In this report, the relevant research results of the Global Energy Interconnection Development  
and Cooperation Organization (GEIDCO) on hydrogen energy are collected, aiming at  
enabling readers to master the technical statuses and development trends of the application,  
production, storage, and transportation of green hydrogen industry, and providing a reference  
for policy makers to fully understand the development prospects of hydrogen energy, formulate  
relevant policies and plan development paths. However, there might be inadequacies as data  
and time for preparation are limited. Comments and suggestions are welcome for further  
improvements.  
III  
SUMMARY  
Hydrogen is not only an important chemical raw material but also efficient zero-carbon energy.  
It has great potential in the energy field in the future. At present, most hydrogen is gray  
hydrogen produced by fossil fuels, and direct use of hydrogen as energy cannot achieve the  
goal of de-carbonization. Renewable energy such as wind energy and solar energy is used to  
produce green hydrogen to achieve the de-carbonization of the whole process from supply to  
consumption, so that the energy de-carbonization can be achieved by developing hydrogen  
energy. Green hydrogen comes from green power. The use of green hydrogen in fields where  
it is difficult to directly use electricity is equivalent to indirectly achieving electrification. An  
electricity-hydrogen coordinated, efficient, flexible, and interconnected zero-carbon energy  
system is built to further accelerate the achievement of overall de-carbonization in the energy  
field, thus promoting the achievement of carbon neutrality.  
In this report, a variety of hydrogen production technologies, hydrogen storage and  
transportation technologies, and hydrogen utilization technologies in the energy, transportation,  
and chemical industries are analyzed, and technology research and judgment and economic  
predictions are made. Based on the economic and social development, energy system  
transition, and energy demand of various industries, the future demand for green hydrogen in  
China is predicted. Based on the research results of GEIDCO in the clean energy power  
generation technology and global clean resource assessment fields, the development potential  
and cost distribution of green hydrogen in China are quantitatively assessed. In this report, an  
overall optimization analysis model for the electricity-hydrogen zero-carbon energy system is  
built, and the long-distance and large-scale green hydrogen allocation optimization scheme  
combining the hydrogen transportation through pipelines with the replacing hydrogen  
transportation with power transmission is preliminarily proposed based on different  
transportation scenarios.  
In terms of hydrogen production technology, the use of renewable energy to produce green  
hydrogen by water electrolysis has significant clean and low-carbon advantages and has great  
development potential. Hydrogen production by water electrolysis includes three technical  
routes: alkaline electrolysis cell (AEC), proton exchange membrane electrolysis cell (PEM) and  
high-temperature solid oxide electrolysis cell (SOEC). At present, the cost of electricity  
accounts for 70%-80% of the cost of green hydrogen. With the decrease in the cost of  
renewable energy power generation, the advancement of electrolytic hydrogen production  
technology, and the increase in the cost of carbon emissions of hydrogen production from  
IV  
fossil fuels, hydrogen production from green power is expected to become the dominant  
hydrogen production method by around 2030. The R&D directions of hydrogen production  
technology include high-efficiency and high-power alkaline electrolysis technology, low-cost  
proton exchange membrane electrolysis technology, and long-life high-temperature solid oxide  
electrolysis technology.  
In terms of hydrogen storage technology, the main hydrogen storage technologies include  
gaseous hydrogen storage, liquid hydrogen storage, and material-based hydrogen storage.  
High-pressure gaseous hydrogen storage technology has low cost, low energy consumption,  
and easy dehydrogenation. It is the most mature and widely used hydrogen storage  
technology and the best choice for large-scale fixed hydrogen storage. Low-temperature liquid  
hydrogen storage and solid hydrogen storage materials will be used in places with high space  
requirements. Hydrogen storage with liquid ammonia and organic liquid has the advantages of  
high hydrogen storage mass fraction and mild hydrogen storage conditions, and it will play a  
role in the long-distance transportation of hydrogen. The R&D directions of hydrogen storage  
technology include hydrogen liquefaction technology, high-pressure hydrogen storage tank  
technology, and solid hydrogen storage material technology.  
In terms of hydrogen transportation technology, the main hydrogen transportation technologies  
include hydrogen transportation through the pipelines, land route, and waterway, and  
replacing hydrogen transportation with power transmission. Various hydrogen transportation  
technologies have their own characteristics and are suitable for different scenarios. For  
small-scale and short-distance hydrogen land transmission, such as medium and  
short-distance hydrogen transportation within cities or between regions, the average  
transportation capacity is less than 10 t/day, the gaseous hydrogen trailers will be mainly used,  
and the unit hydrogen transportation cost is RMB 3-6/kg. For small-scale and medium-distance  
hydrogen land transportation, the liquid hydrogen tank trucks will be mainly used, and the unit  
hydrogen transportation cost is RMB 5-10/kg. For large-scale and long-distance hydrogen  
transportation, such as hydrogen transportation from large-scale green hydrogen production  
bases to urban consumers and others, the combination of hydrogen transportation through  
pipelines with the replacing hydrogen transportation with power transmission will be used. At  
present, the construction cost of pure hydrogen pipelines is about 1.5 times that of natural gas  
pipelines, and the cost of hydrogen transportation pipelines with a transmission capacity of  
about 20 billion m3/a is about RMB 20 million/km. By 2030, the pure hydrogen pipeline  
V
manufacturing technology and the pressure reduction and pressure regulation technology are  
expected to be mature, and the construction cost of pure hydrogen pipelines is expected to  
decrease to be equivalent to the current cost of natural gas pipelines. By 2050, new hydrogen  
transportation pipelines made of fiber-reinforced polymer composites and others are expected  
to be put into commercial use, and the transmission loss of large-scale hydrogen transportation  
pipelines is expected to further decrease, so the hydrogen transportation cost is expected to  
reach about RMB 2/kg.  
In terms of hydrogen utilization technology, the application of green hydrogen is an extension  
of green power, and it is also an important way to achieve indirect electricity replacement in  
chemical, metallurgy, aviation, and industrial high-grade heating industries. Green hydrogen is  
mainly used for the synthesis of fuels or raw materials such as ammonia, methanol, and  
methane in the chemical field, and it can replace gray hydrogen in traditional processes. The  
technology in this field is mature, and the degree of promotion mainly depends on the carbon  
emission constraint policy and the cost-effectiveness of green hydrogen. Green hydrogen can  
be used as the reducing agent to produce direct reduced iron in the metallurgical field, and it  
can replace coal and natural gas. Hydrogen metallurgy is an important solution to achieve  
decarbonization in the iron and steel industry. Green hydrogen is applied based on two  
technical routes of fuel cells and hydrogen fueled gas turbines in the power generation field to  
provide long-term regulation capacity and electricity supply security for the system. In the  
transportation field, green hydrogen is mainly applied in scenarios where it is difficult to  
achieve direct electrification such as public transits, heavy trucks, ships, and airplanes. The  
main applications include hydrogen fuel cell buses and hydrogen fuel cell trucks. The R&D  
directions of hydrogen application technology include hydrogen fuel cell and gas turbine  
technology, green hydrogen chemical technologies such as ammonia, methanol and methane  
production from green hydrogen, hydrogen energy transportation technologies such as  
hydrogen fuel cell vehicles, hydrogen energy airplanes and hydrogen energy ships, pure  
hydrogen iron and steel smelting technology, and hydrogen heating technology.  
In terms of green hydrogen demand, based on the overall idea of achieving carbon neutrality  
proposed by GEIDCO and the action plans for de-carbonization in various fields, and in  
combination with the energy demand of various industries, the demand for raw materials and  
the development level of hydrogen utilization technology, the future demand for green  
hydrogen in China is predicted in this report. Based on the development trend and economic  
VI  
analysis of green hydrogen application technology and in combination with China's energy  
consumption structure and characteristics, green hydrogen will play an important carbon  
mitigation role in the industry, power generation, and transportation fields. The demand for  
green hydrogen in China is expected to be about 4 Mt, and to enter a stage of rapid growth by  
2030, and the demand for green hydrogen is expected to reach 61 Mt by 2050. The demand  
for hydrogen in the industrial field such as new green hydrogen chemical industry, metallurgy  
industry, manufacturing industry, and industrial high-grade heating industry is expected to be  
36 Mt, the demand for hydrogen in the transportation field is expected to be 15.5 Mt, and the  
demand for hydrogen in other fields including power generation and construction is expected  
to be about 9.5 Mt. By 2060, the demand for green hydrogen is expected to be 75 Mt, and the  
demand for hydrogen in traditional industries such as petrochemical industry and others is  
expected to be 20 Mt and it will still be met by hydrogen in the industrial process. The total  
demand for hydrogen is expected to reach 95 Mt, accounting for 10% of the final energy  
consumption. Considering the cost of carbon emissions, the economic advantages of green  
hydrogen replacing fossil fuels in the industry, power generation, and transportation fields will  
be quickly reflected, and the green hydrogen industry will be started 3-5 years in advance.  
In terms of the development potential of green hydrogen, the green hydrogen production  
potential assessment algorithm and cost optimization model are built, and the assessment of  
green hydrogen production potential in China and the cost distribution study are completed in  
this report. The results show that the potential for green hydrogen production is great, and the  
upper limit of technical potential capacity of green hydrogen in China is 3.7 Gt/a, reaching  
about 40 times the total demand for hydrogen by 2060. In terms of the cost-effectiveness of  
green hydrogen, by around 2030, the cost of green hydrogen production in areas with good  
conditions in western and northern China can be as low as RMB 15-16/kg, and the economic  
advantages of green hydrogen will be gradually reflected. By 2050, the cost of green hydrogen  
production in China is expected to reach RMB 7-11/kg and further decrease to RMB 6-10/kg by  
2060, and it can be as low as RMB 5-7/kg in areas with good conditions in western and  
northern China. Hydrogen production from green power will become the most important  
hydrogen production method.  
In terms of green hydrogen allocation study, green hydrogen comes from green power, and it  
can also come from power generated by fuel cells or hydrogen fuled gas turbines. These two  
modes can be easily converted to each other to achieve electricity-hydrogen coordination. An  
VII  
electricity-hydrogen zero-carbon energy system model is built in this report. It covers the  
technical links such as production, transmission, and storage of green power and green  
hydrogen. With the goal of optimizing the system economy, all elements of power, grid, load  
and storage are optimized. The results show that the electricity-hydrogen zero-carbon energy  
system can give full play to the advantages of easy transmission of power and easy storage of  
hydrogen, to improve the flexibility of the system, and improve the utilization efficiency of  
renewable energy power generation and hydrogen production equipment, and electricity and  
hydrogen transportation channels, thus reducing the overall energy consumption cost. Based  
on the above model, the allocation of green hydrogen in China is studied in this report. By 2030,  
the green hydrogen is expected to be mainly produced and utilized locally. The total amount of  
inter-regional hydrogen transportation between the western region and the eastern and central  
regions is expected to be 1 Mt, and the mode of replacing hydrogen transportation with power  
transmission will be used (50 TWh). By 2060, the total amount of inter-regional hydrogen  
transportation between regions is expected to be 35 Mt (about 47% of the green hydrogen  
demand), including about 8 Mt of hydrogen transmitted directly by pipelines. The electricity  
transmitted by replacing hydrogen transportation with power transmission is expected to be  
1100 TWh (equivalent to 27 Mt of hydrogen, accounting for more than 75% of the total  
transmission capacity). To meet the requirements of inter-regional hydrogen energy allocation,  
about 93 GW new transmission channels are built, and three new hydrogen transportation  
pipelines (Northwest China-Central China, Northwest China-East China, and Southwest  
China-South China) are built. By 2060, the application of green hydrogen in the final energy  
consumption fields can reduce the consumption of fossil fuels by 390 Mtce and reduce the  
carbon emissions by 620 Mt, which is equivalent to about 40% of the carbon emissions from  
energy activities. The coordinated allocation of electricity and hydrogen can give full play to the  
flexibility value of hydrogen energy, the guarantee value of electricity supply, the safety value of  
the system, and the “last kilometer” carbon reduction function of green hydrogen in the  
process of carbon neutrality.  
VIII  
CONTENTS  
PREFACE  
SUMMARY  
Current Situation and Trend of Hydrogen Energy Development  
001  
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1
1.1 Introduction to Hydrogen  
002  
004  
007  
008  
010  
013  
014  
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1.2 Development Status  
1.3 Green Hydrogen and Energy Transition  
1.3.1 Challenges of Energy Transition  
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1.3.2 Green Hydrogen and Energy Transition  
1.3.3 Green Hydrogen and New Power System  
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1.4 Reporting Ideas and Main Contents  
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Key Technologies for Green Hydrogen  
017  
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2
2.1 Hydrogen Production Technology  
2.1.1 Current Technical Status  
2.1.2 Technology Comparison  
018  
018  
033  
035  
037  
038  
038  
053  
059  
061  
062  
063  
085  
097  
100  
101  
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2.1.3 R&D Direction  
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2.1.4 Technical and Economic Trends  
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2.2 Storage and Transportation Technology  
2.2.1 Current Technical Status  
2.2.2 Technology Comparison  
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2.2.3 R&D Direction  
2.2.4 Technical and Economic Trends  
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2.3 Hydrogen Utilization Technology  
2.3.1 Current Technical Status  
2.3.2 Technology Comparison  
2.3.3 R&D Direction  
2.3.4 Technical and Economic Trends  
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2.4 Summary  
IX  
Green Hydrogen Demand Projection and Development Potential  
105  
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3
4
3.1 Demand Forecast  
106  
106  
115  
117  
118  
131  
132  
134  
135  
136  
138  
142  
144  
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3.1.1 Economic and Social Development Expectation  
3.1.2 Prospect of Energy Scenarios  
3.1.3 Projection Models and Methods  
3.1.4 Analysis of Main Hydrogen Fields  
3.1.5 Demand Projection Results  
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3.1.6 Scenario of China Energy Interconnection  
3.2 Development Potential and Cost  
3.2.1 Cost Projection of New Energy Power Generation  
3.2.2 Assessment of New Energy Resources  
3.2.3 Development Potential and Cost Optimization Model  
3.2.4 Assessment Results  
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3.3 Summary  
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Electricity-Hydrogen Coordinated Zero-carbon Energy System  
147  
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4.1 Necessity of Electricity-Hydrogen Coordinated Allocation  
148  
149  
149  
150  
158  
161  
161  
163  
167  
170  
170  
172  
174  
175  
176  
178  
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4.2 Optimal Allocation Model  
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4.2.1 Model and Algorithm  
4.2.2 Analysis of Typical Scenarios  
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4.2.3 Comparison of Different Scenarios  
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4.3 Study on Allocation of Green Hydrogen in China  
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4.3.1 Control Scenario  
4.3.2 Green Hydrogen Allocation Research  
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4.3.3 Electricity-hydrogen Coordinated Zero-carbon Energy System  
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4.4 Comprehensive Values  
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4.4.1 Value of Flexibility  
4.4.2 Guarantee Value of Electricity Supply  
4.4.3 Value of System Security  
4.4.4 Value of Emission Reduction  
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4.5 Hydrogen Power Generation and Green Energy Center  
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4.6 Summary  
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Conclusion and Prospect  
181  
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5
5.1 Key Technology Prospects  
5.2 Green Hydrogen Demand Prospects  
5.3 Green Hydrogen Industry Prospects  
182  
184  
185  
185  
188  
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5.3.1 Policy Planning  
5.3.2 Industry Chain Development  
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X
5.3.3 Market and Service Platform  
190  
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Appendix  
193  
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Appendix 1 Basic Data Sources and Details  
193  
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Appendix 2 Recommended Values of Main Parameters for Wind, Light, and Clean  
Energy Assessment  
196  
199  
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Appendix 3 Resource-Assessment-Demand Hierarchical Optimization Algorithm  
Appendix 4 Optimization Model and Method of Electro-hydrogen Coordinated  
·······  
System  
200  
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XI  
LIST OF FIGURES  
Figure 1.1 Main Links of Hydrogen Energy Industry Chain...........................................................004  
Figure 1.2 Development Objectives in Japan’s Basic Strategy for Hydrogen Energy...................005  
Figure 1.3 Schematic Diagram of the Vital Link of Hydrogen........................................................011  
Figure 1.4 Schematic Diagram of Energy-matter Conversion System..........................................012  
Figure 1.5 Research Ideas and Main Research Contents of the Report.......................................015  
Figure 2.1 Sources of Hydrogen in China......................................................................................019  
Figure 2.2 Schematic Diagram of Structure of PEM Electrolysis Cell...........................................020  
Figure 2.3 Schematic Diagram of Principle of Oxygen Conducting and Proton Conducting  
SOEC............................................................................................................................021  
Figure 2.4 Structure of Hydrogen Production Cost in Single-electroAlkaline Electrolysis Cell.....022  
Figure 2.5 Unit Investment of Alkaline Electrolysis Cell.................................................................023  
Figure 2.6 Relationship between Cost of Hydrogen Production by Water Electrolysis and  
Electricity Price.............................................................................................................024  
Figure 2.7 Relationship between Cost of Hydrogen Production by Water Electrolysis and  
Equipment Scale...........................................................................................................024  
Figure 2.8 Relationship between Cost of Hydrogen Production by Water Electrolysis and  
Equipment Utilization Rate ...........................................................................................025  
Figure 2.9 Cost Structure of Electrolytic Hydrogen Production Considering Seawater  
Desalination ..................................................................................................................029  
Figure 2.10 Schematic Diagram of Hydrogen Production Process by Steam Reforming of  
Natural Gas with Carbon Capture Technology...........................................................030  
Figure 2.11 Energy and Material Cycles of Hydrogen Production from Biomass .........................032  
Figure 2.12 Schematic Diagram of Water Photolysis....................................................................033  
Figure 2.13 Comparison of Carbon Emission and Production Cost of Green Hydrogen, Blue  
Hydrogen and Gray Hydrogen ...................................................................................038  
Figure 2.14 Schematic Diagram of Fiber-wound Composite Storage Tank Structure ..................040  
Figure 2.15 Global Status of Dedicated Hydrogen Pipeline Networks..........................................045  
XII  
Figure 2.16 Constructors and Operators of Dedicated Hydrogen Pipeline Networks Around the  
World..........................................................................................................................045  
Figure 2.17 Scientific Diagram of Hydrogen Pipeline Network in the Gulf of Mexico, United  
States.........................................................................................................................046  
Figure 2.18 Relationship between Transportation Cost and Transportation Distance of Hydrogen  
Pipelines.....................................................................................................................047  
Figure 2.19 Relationship between Transportation Cost and Transportation Distance of Tube  
Trailers........................................................................................................................049  
Figure 2.20 Relationship between Transportation Cost and Transportation Distance by Liquid  
Hydrogen Tank Trucks ...............................................................................................050  
Figure 2.21 Schematic Diagram of Hydrogen Transportation by Marine System Using  
Methylcyclohexane ....................................................................................................051  
Figure 2.22 Schematic Diagram of “Replacing Hydrogen Transportation with Power  
Transmission”.............................................................................................................052  
Figure 2.23 Applicable Scenarios of Different Hydrogen Transportation Technologies................056  
Figure 2.24 Comparison in the Cost-effectiveness of Three Transportation Methods on  
Small-scale And Short-distance Transportation Cases.............................................056  
Figure 2.25 Comparison in the Cost-effectiveness of Three Transportation Methods on  
Small-scale And Medium-distance Transportation Cases.........................................058  
Figure 2.26 Current Hydrogen Consumption of Each Industry in China ......................................063  
Figure 2.27 Schematic Diagram of Carbon Cycle ........................................................................067  
Figure 2.28 Schematic Diagram of Power-Hydrogen-Power Conversion Process ......................068  
Figure 2.29 Operating Principle and Mechanical Structure of Gas Turbine..................................069  
Figure 2.30 Operating Principle of Hydrogen Fuel Cell.................................................................071  
Figure 2.31 Structural Diagram of Fuel Cell Vehicle......................................................................075  
Figure 2.32 Relation Diagram of Main Modules of Fuel Cell Vehicle ............................................076  
Figure 2.33 Cost Structure of Fuel Cell Vehicle ............................................................................076  
Figure 2.34 Flow Chart of Hydrogen Refueling.............................................................................077  
Figure 2.35 Two Technical Routes of Hydrogen Refueling Stations .............................................079  
Figure 2.36 Schematic Diagram of Turbine Propulsion System for Hydrogen Aircraft.................080  
Figure 2.37 Schematic Diagram of Fuel Cell Propulsion System for Hydrogen Aircraft...............081  
Figure 2.38 Structure Layout of Whole Hydrogen Ship System ...................................................082  
Figure 2.39 Steelmaking Flow Chart.............................................................................................083  
Figure 2.40 Comparison of Pure Hydrogen Ironmaking Process and Conventional Blast Furnace  
Ironmaking Process ...................................................................................................084  
XIII  
Figure 2.41 Comparison of the Power System Structure Between Hydrogen Fuel Cell  
Vehicles and BEVs......................................................................................................092  
Figure 2.42 Comparison of Carbon Emissions in Different Steel Smelting Paths.........................095  
Figure 2.43 Comparison Results of Hydrogen, Electric and Coal Heating ...................................096  
Figure 3.1 China’s GDP and Growth Rate from 2000 to 2020 ......................................................107  
Figure 3.2 Change in Proportion of Added Value of Three Industries in China from  
2000 to 2020.................................................................................................................107  
Figure 3.3 Three Projections of China’s Industrial Structure from 2020 to 2060...........................111  
Figure 3.4 Total Population and Natural Growth Rate of Chinese Mainland from  
1990 to 2019.................................................................................................................112  
Figure 3.5 Trend of Urban and Rural Population and Urbanization Rate in China from  
2000 to 2019.................................................................................................................113  
Figure 3.6 Population Projection of Chinese Mainland from 2020 to 2060...................................115  
Figure 3.7 Schematic Diagram of Hydrogen Demand Projection Model ......................................117  
Figure 3.8 Historical Statistics of Ammonia Output and Growth Rate..........................................119  
Figure 3.9 Historical Statistics of Methanol Output and Growth Rate ..........................................119  
Figure 3.10 Historical Statistics of Natural Gas Output, Import and Growth Rate in China..........120  
Figure 3.11 Process and Results of Hydrogen Projection for Green Hydrogen Chemical  
Industry in 2050..........................................................................................................121  
Figure 3.12 Historical Statistics of Steel Output and Growth Rate ...............................................123  
Figure 3.13 Process and Results of Hydrogen Projection for Green Hydrogen Ironmaking in  
2050............................................................................................................................124  
Figure 3.14 Status of Inventory of Cars and Trucks in China........................................................125  
Figure 3.15 Process and Results of Hydrogen Projection for Transportation in 2050 ..................126  
Figure 3.16 Net Load Curve at Long-term Time Scale (Taking North China as An Example) .......128  
Figure 3.17 Historical Statistics of Heating Area and Growth Rate in China ................................129  
Figure 3.18 Process and Results of Hydrogen Projection for Green Hydrogen Heating in  
2050............................................................................................................................130  
Figure 3.19 Projection Results of China’s Hydrogen Demand in Various Fields in  
2030 and 2060............................................................................................................131  
Figure 3.20 Projection Results of Green Hydrogen Replacement Rate in China’s  
Sub-Industries in 2060 ...............................................................................................132  
Figure 3.21 Total Amount and Structure of Primary Energy..........................................................133  
Figure 3.22 Total Amount and Structure of Final Energy Consumption ........................................134  
XIV  
Figure 3.23 Schematic Diagram of Green Hydrogen Production Potential and Cost Assessment  
...................................................................................................................................135  
Figure 3.24 Technical Roadmap for Assessment of Wind and Photovoltaic Power  
Resources..................................................................................................................137  
Figure 3.25 Schematic Diagram of Green Hydrogen Potential and Cost Optimization  
Modeling ....................................................................................................................139  
Figure 3.26 Schematic Diagram of The Impacts of Wind-solar Proportion and Electricity  
Abandonment Rate on Green Hydrogen Cost...........................................................142  
Figure 3.27 Schematic Diagram of The Potential Distribution of Green Hydrogen Production in  
China..........................................................................................................................143  
Figure 3.28 Schematic Diagram of Green Hydrogen Production Cost Distribution in China in  
2030...........................................................................................................................143  
Figure 3.29 Schematic Diagram of Green Hydrogen Production Cost Distribution in China in  
2050...........................................................................................................................144  
Figure 3.30 Schematic Diagram of Green Hydrogen Production Cost Distribution in China in  
2060...........................................................................................................................145  
Figure 4.1 Schematic Diagram of Electricity-Hydrogen Coordinated Energy System..................149  
Figure 4.2 Basic Architecture of Electricity-Hydrogen Coordinated System Model.....................150  
Figure 4.3 Output Characteristics of Wind Power and Solar PV Power in Western  
China (Hours)................................................................................................................151  
Figure 4.4 Annual Electricity Load Curve of a Province in Western and East-Central  
China (Hours)................................................................................................................152  
Figure 4.5 Typical Daily Electricity Load Curve of a Province in Northwestern China..................152  
Figure 4.6 Typical Daily Electricity Load Curve of a Province in East-Central China....................152  
Figure 4.7 Forecast of Hydrogen Demand of a Province in East-Central China...........................153  
Figure 4.8 Forecast of Hydrogen Demand of a Province in Northwestern China.........................153  
Figure 4.9 Production, Transmission, and Consumption of Electricity and Hydrogen  
Under the Technology Continuation Scheme ..............................................................155  
Figure 4.10 Separate Transmission of Power and Hydrogen Under the Technology  
Continuation Scheme ................................................................................................156  
Figure 4.11 Production, Transmission, and Consumption of Electricity and Hydrogen  
Under the Technology Progress Scheme ..................................................................156  
Figure 4.12 Optimal Allocation Schemes of Green Hydrogen in Different Scenarios...................158  
Figure 4.13 Schematic Diagram of Inter-regional Power Flow in China by 2060 .........................162  
XV  
Figure 4.14 Schematic Diagram of Inter-regional Hydrogen Allocation of China in 2060.............166  
Figure 4.15 Schematic Diagram of Electricity-Hydrogen Coordinated Allocation of China in  
2060............................................................................................................................168  
Figure 4.16 The Typical Weekly Electricity Balance of Northwest China and East China.............170  
Figure 4.17 Changes in Electricity Balance and Storage of Hydrogen in China Throughout  
the Year.......................................................................................................................171  
Figure 4.18 Statistical Results of Continuous Days of Weather Conditions with Extremely Low  
Wind and PV Output of East China............................................................................173  
Figure 4.19 Electricity Balance in Extreme Weather of East China Power Grid............................174  
Figure 4.20 Power Changes of Wind, PV, and Hydrogen in Extreme Weather of East China  
Power Grid .................................................................................................................174  
Figure 4.21 Comparison of Voltage Recovery Curves after AC Fault in a Certain Place of  
Central and Eastern Regions......................................................................................175  
Figure 4.22 Schematic Diagram of Urban Green Energy Center...................................................177  
XVI  
LIST OF TABLES  
Table 1.1 Comparison of Heat Values and Carbon Emissions of Common Fuels........................003  
Table 2.1 Comparison of Characteristics and Parameters of Three Technologies for  
Hydrogen Production by Water Electrolysis..................................................................022  
Table 2.2 Application of Some Domestic and Overseas Commercial Water Electrolysis  
Devices..........................................................................................................................025  
Table 2.3 Technical Features and Cost-effectiveness Comparison of Main Hydrogen  
Production Technologies at Present .............................................................................035  
Table 2.4 Main Research Institutions and Achievements of Full Composite Light Fiber  
Wound Storage Tanks ...................................................................................................041  
Table 2.5 Composition of Hydrogen Transportation Cost through Pipelines................................047  
Table 2.6 Composition of Transportation Cost by Tube Trailer.....................................................048  
Table 2.7 Composition of Transportation Cost by Liquid Hydrogen Tank Trucks.........................049  
Table 2.8 Comparison of Characteristics of Main Hydrogen Storage Technologies ....................053  
Table 2.9 Comparison of Characteristics of Main Hydrogen Transportation Technologies..........055  
Table 2.10 Comparison of Hydrogen Storage and Transportation in Liquid Hydrogen,  
Methylcyclohexane, and Liquid Ammonia...................................................................057  
Table 2.11 Transportation Cost per Unit Volume of Natural Gas and Hydrogen ..........................058  
Table 2.12 Investment Cost of UHV DC Transmission Projects....................................................059  
Table 2.13 Unit Cost of Power, Hydrogen, and Natural Gas Transmission...................................059  
Table 2.14 Main Hydrogen Units and Hydrogen Consumption of the Refinery............................064  
Table 2.15 Hydrogen Utilization Methods in the Building Field and Some Demonstration  
Projects........................................................................................................................074  
Table 2.16 Technical and Economic Comparison of Fuel Cell and Hydrogen Fueled Gas  
Turbine Power Generation ...........................................................................................091  
Table 2.17 Comparison of Energy Efficiency Between Hydrogen Fuel Cell Vehicles and  
BEVs and Gasoline Vehicles........................................................................................093  
Table 2.18 Comparison of Cost-effectiveness Among Small Passenger Hydrogen Fuel  
Vehicles, Electric Vehicles and Gasoline Vehicles .......................................................093  
XVII  
Table 2.19 Comparison of Cost-effectiveness Among Hydrogen Fuel Vehicles, Electric  
Vehicles and Diesel Vehicles for Public Transit ............................................................093  
Table 2.20 Comparison of Carbon Emissions of Hydrogen Fuel Cell Vehicles, Electric  
Vehicles and Gasoline Vehicles....................................................................................094  
Table 3.1 Projection of China’s Economic Growth from 2020 to 2060..........................................110  
Table 3.2 Projections of China’s Population Development by Various Institutions .......................114  
Table 3.3 Projection of Green Hydrogen Demand in Future Green Hydrogen Chemical  
Industry..........................................................................................................................122  
Table 3.4 Projection of Green Hydrogen Demand in Future Green Hydrogen Metallurgical  
Industry..........................................................................................................................124  
Table 3.5 Projection of Green Hydrogen Demand in Future Green Hydrogen Transportation ......127  
Table 3.6 Demand Projection of Green Hydrogen in Heating Industry..........................................131  
Table 4.1 Costs of Hydrogen Transportation Pipelines in Two Scenarios.....................................154  
Table 4.2 Technical Cost Parameters ............................................................................................154  
Table 4.3 Energy Conversion and Storage Efficiency....................................................................155  
Table 4.4 Comparison of Investment Costs of Different Equipment under Two Schemes ...........157  
Table 4.5 Inter-regional Power Flow in China by 2060 ..................................................................162  
Table 4.6 Comparison of Optimal Results of Four Modes ............................................................165  
Table 4.7 Added Inter-regional Power Flow and Hydrogen Flow of China in 2060.......................167  
Table 4.8 Results of Electricity-Hydrogen Coordinated Allocation of China in 2060 ....................169  
XVIII  
1
Current Situation and Trend of Hydrogen Energy Development  
Current Situation  
and Trend of  
Hydrogen Energy  
Development  
The Development and Outlook of Green Hydrogen  
Since the beginning of the 21st century, a new round of energy revolution has  
flourished, and the energy industry in the world is transforming towards a clean,  
zero-carbon, and sustainable development direction. Hydrogen, as a clean and  
efficient energy source, has attracted more and more attention. In particular,  
hydrogen from renewable energy such as wind energy and solar energy can  
achieve zero carbon emissions in the whole process of energy production and  
consumption. In the future, hydrogen will play an important role in the  
zero-carbon energy system and the carbon neutrality society.  
1.1 Introduction to Hydrogen  
Human beings have dreamed of using hydrogen as an energy source for a long time.  
Cavendish first recognized and isolated hydrogen in 1766. Grove designed the earliest  
hydrogen-oxygen fuel cell in 1839. Otto first experimented with a mixed gas containing 50%  
hydrogen on an internal combustion engine in 1870. Jules Verne even described hydrogen as  
the future coal in The Mysterious Island. Hydrogen was used as an energy source to propel  
human beings into space in the middle of the 20th century.  
The chemical symbol of hydrogen is H and its atomic weight is about 1. Hydrogen is the first  
element in the periodic table of elements. It has unique properties, mainly including the  
following aspects.  
Raw materials for hydrogen production are abundant and inexhaustible. Hydrogen is the  
earliest and most abundant element in the universe, accounting for about 75% of the mass of  
the universe. Due to its active chemical properties, it hardly exists in the form of a simple  
substance on the earth, and it is mainly in the form of a compound. It is an important  
component of water, methane, and other organic matters. Taking hydrogen production by  
water electrolysis as an example, the total amount of water on the earth is about 1.4 billion km3,  
and the water body covers an area of more than 70% of the area of the earth’s surface. If all the  
hydrogen in water is extracted, about 1.5×1017 t hydrogen fuels can be obtained, and the  
energy is nearly 10,000 times that of all fossil fuels on the earth.  
It is chemically active and is an important chemical raw material. Hydrogen is the first element  
in the periodic table of elements. It has strong reducibility. Under certain conditions, almost all  
elements can react with hydrogen to form compounds. Hydrogen is a key component of most  
acids, alkalis, and organic matters. It is often used in chemical processes such as petroleum  
refining, ammonia production, and methanol production, as well as industrial processing  
processes such as semiconductor production and others. It is one of the most important  
chemical raw materials. At present, most of the hydrogen produced in the world is used in the  
chemical industry.  
002  
1
Current Situation and Trend of Hydrogen Energy Development  
It has high energy density and has great potential as an energy source. Among the common  
fuels, hydrogen has the highest heat value per unit mass. The heat released by hydrogen  
combustion is equivalent to 2.6 times that of natural gas, 3.3 times that of gasoline, and 5-9  
times that of coal with the same mass. This is determined by the characteristics of hydrogen  
itself and the chemical nature of combustion (violent oxidation-reduction reaction). The  
hydrogen atom contains only one electron, and oxidation-reduction reaction is easy to be  
occurred with oxygen, so hydrogen is very easy to burn or even explode. During combustion,  
the more electrons are transferred, the more energy is released. Hydrogen is the lightest  
element. Compared with other elements, the number of outer electrons that can be transferred  
per unit mass is the largest, so hydrogen has the highest energy density per unit mass.  
Hydrogen is the best choice for high-end fuel in aerospace and other fields.  
The combustion products are clean, and zero carbon emissions on the energy consumption  
side can be achieved. Different from fossil fuels, hydrogen does not produce other pollutants  
such as sulfur dioxide, nitrogen oxides, and respirable particulate matter, or any carbon  
emissions during the energy release. With hydrogen as the energy source, clean and zero  
carbon emissions on the energy consumption side can be achieved. If there is no carbon  
emission in the process of hydrogen production, such as hydrogen production from renewable  
energy including wind energy and solar energy, hydrogen production from biomass, and  
hydrogen production by water photolysis, hydrogen will become a true zero-carbon energy  
source. The feature is similar to electricity. The energy released by the combustion per unit  
mass of hydrogen and other fuels, and the carbon emissions produced are shown in Table 1.1.  
Table 1.1 Comparison of Heat Values and Carbon Emissions of Common Fuels  
CO2 emission  
Higher calorific value  
(MJ/kg)  
Fuel  
(kg/kg,CO2/fuel)  
Hydrogen  
Natural gas  
Gasoline  
Coal  
143  
56  
0
2.8  
43  
3.1  
15-30  
22.7  
2.2-3.5  
1.4  
Methanol  
In recent years, the “color” of hydrogen is common in major media and various reports. Except  
for different technical routes, the largest gap among “gray hydrogen”, “blue hydrogen” and  
“green hydrogen” is the carbon emission intensity during hydrogen production. Generally,  
“gray hydrogen” usually refers to hydrogen produced from fossil fuels, and a large amount of  
CO2 emissions will be generated during production. “Blue hydrogen” refers to hydrogen  
produced from fossil fuels combined with carbon capture, utilization and storage (CCUS)  
technology. “Green hydrogen” refers to hydrogen produced from clean energy such as wind  
energy, solar energy, and biomass, with zero carbon emissions during production. The  
hydrogen production by water electrolysis from clean energy has the most potential and the  
technology is relatively mature, so it is the focus of future development. Unless otherwise  
specified, the green hydrogen described herein refers to the hydrogen produced by water  
electrolysis from clean energy, and correspondingly, green electricity refers to clean electricity.  
003  
The Development and Outlook of Green Hydrogen  
1.2 Development Status  
At present, hydrogen consumption in the world reaches 115 Mt per year, and most of the  
hydrogen is used in the chemical industry. Although hydrogen has many advantages as an  
energy source, it is rarely used directly as an energy source except for in a few fields such as  
aerospace field and others. The main reason is that hydrogen only exists in the form of  
compounds in nature, and the acquisition of pure hydrogen requires additional chemical  
processes, which often reduces the overall energy conversion efficiency and increases the  
energy consumption cost. The hydrogen energy industry has been developing slowly for a long  
time due to the long-term high cost of hydrogen and the constraints of technological  
bottlenecks related to hydrogen application and hydrogen storage. In recent years, due to the  
requirements of human beings for clean, low-carbon and sustainable development, the  
technological progress of the whole hydrogen energy industry chain, and the resource and  
climate crises caused by the excessive application of fossil fuels, the value of hydrogen energy  
in the energy transition process has received increasing attention.  
The hydrogen energy industry chain includes four main links of hydrogen production, storage  
and transportation, refueling, and final application, as shown in Figure 1.1. In general, the  
hydrogen production technology is relatively mature, the infrastructure related to storage and  
transportation is still relatively backward, and the application of hydrogen in transportation,  
metallurgy and other fields remains to be developed.  
Figure 1.1 Main Links of Hydrogen Energy Industry Chain  
1. Japan  
Japan, as an energy-deficient country, has focused on hydrogen energy very early. As early as  
1973, when the first oil crisis broke out, the “Hydrogen Energy Systems Society of Japan” was  
established to carry out the research and development of hydrogen energy technology with  
university researchers as the center. In 2014, the Japanese government positioned hydrogen  
energy as the core secondary energy alongside electricity and thermal energy in its Fourth  
Basic Energy Plan, and proposed the vision of building a “hydrogen energy society”, hoping to  
achieve the application of hydrogen energy in households, industry, transportation and even  
004  
1
Current Situation and Trend of Hydrogen Energy Development  
the whole society through hydrogen fuel cells, so as to achieve true energy security and energy  
independence. In 2017, the Japanese government issued the Basic Strategy for Hydrogen  
Energy, with the main objectives of achieving the commercialization of hydrogen energy power  
generation by around 2030 to reduce carbon emissions and increase energy self-sufficiency.  
The specific development objectives are shown in Figure 1.2. In 2018, the Japanese government  
issued the Fifth Basic Energy Plan, proposing that the relevant policies and measures in the  
Basic Strategy for Hydrogen Energy will be fully implemented, and an international industry  
chain of hydrogen production, storage, transportation, and utilization will be built to actively  
promote the development of hydrogen fuel power generation and hydrogen fuel vehicles.  
Figure 1.2 Development Objectives in Japan’s Basic Strategy for Hydrogen Energy  
Over the past 30 years, the Japanese government has invested hundreds of billions of JPY in  
the R&D and promotion of hydrogen energy and fuel cell technology, and subsidized relevant  
infrastructure and end users. Japan ranks first in the world in the number of patents for  
hydrogen energy and fuel cell technology, and it has entered the early stages of  
commercialization for the FCV and domestic fuel cell cogeneration systems.  
2. EU  
In the process of promoting the industrialization of hydrogen energy, EU countries have  
intensively introduced a series of industrial support policies, invested a large number of funds  
in technology R&D, and emphasized the commercial promotion of fuel cells in the  
transportation field and the construction of hydrogen energy infrastructure. In 2008, the EU  
issued the Fuel Cells and Hydrogen Joint Undertaking (FCH-JU) Project and invested EUR 940  
million in the R&D of hydrogen energy and fuel cells from 2008 to 2013. An additional  
investment of EUR 700 million was made in 2010. The project plays a crucial role in promoting  
the application of hydrogen energy and fuel cells in Europe. In 2012, the EU implemented the  
Ene-field Project. The project covers 12 EU member states and nine fuel cell system  
005  
The Development and Outlook of Green Hydrogen  
manufacturers, and the project investment is EUR 53 million. In 2013, the EU announced the  
launch of the Horizon 2020 Programme, and the investment of EUR 22 billion is expected to be  
made in the hydrogen energy and fuel cell industry by 2020. In 2015 and 2016, the EU  
successively launched the Hydrogen Mobility Europe H2ME 1 Programme and H2ME 2  
Programme, with a total planned investment of EUR 170 million to build 49 hydrogen refueling  
stations and 1400 hydrogen fuel cell vehicles. In February 2019, the Fuel Cells and Hydrogen  
Joint Undertaking released the Hydrogen Roadmap Europe: A Sustainable Pathway for the  
European Energy Transition, proposing the hydrogen energy development roadmap for 2030  
and 2050. The report suggests that the output value of the hydrogen energy industry in the EU  
is expected to reach EUR 130 billion by 2030 and EUR 820 billion by 2050.  
3. USA  
The hydrogen energy industry in the United States has also moved from technology R&D to  
demonstration and promotion. At the enterprise level, the United States already has  
representative enterprises in the upstream, midstream and downstream of the hydrogen  
energy industry chain, including technical segments such as proton exchange membrane  
electrolysis cells, hydrogen storage and transportation infrastructure solutions, fuel cells, and  
hydrogen-fueled gas turbines.  
The United States has always maintained the development ideas from policy evaluation,  
commercialization prospect forecasting, scheme formulation, technology R&D, and  
demonstration and promotion since it formulated policies to promote the development of the  
hydrogen energy industry in 1990. Considering issues related to commercial promotion, the  
U.S. government launched the Hydrogen Energy Prospects Act in 1996, deciding to invest  
USD 160 million in R&D of hydrogen production, storage, transportation, and application  
technologies from 1996 to 2001, and focusing on demonstrating and demonstrating the  
technical feasibility of using hydrogen energy in the industry, housing, and transportation. In  
2012, Obama, then President of the United States, submitted a 2013 government budget of  
USD 3.8 trillion to the United States Congress, including USD 6.3 billion allocated to the U.S.  
Department of Energy for R&D of clean energy such as hydrogen energy, fuel cells, and  
alternative fuels for vehicles. Therefore, higher requirements are put forward for the efficiency  
conversion of fuel cell systems, and a tax credit of 30%−50% is imposed on the hydrogen  
energy infrastructure in the United States. In 2016, the United States set the hydrogen price  
target and planned to reduce the hydrogen price to USD 7/GGE (equivalent to the energy of  
one gallon of gasoline) by 2020 and extend the tax credit policies of various states. Eight states  
including California, Connecticut, Maryland, Massachusetts, New York, Oregon, Rhode Island,  
and Vermont have also signed the Memorandum of Understanding for State Zero-Emission  
Vehicle Programs and planned to develop 3.3 million renewable energy vehicles including  
hydrogen fuel cell vehicles by 2025.  
4. China  
China is the world’s largest country for hydrogen production, and its production capacity  
accounts for about 40% of the world’s total, mainly from fossil fuels. The production capacity of  
hydrogen produced through coal gasification and steam reforming of hydrocarbons accounts  
for about 96% of the national hydrogen production capacity. China’s technologies related to  
006  
1
Current Situation and Trend of Hydrogen Energy Development  
hydrogen energy such as fuel cells and others basically have the foundation for industrialization.  
China has mastered some core fuel cell technologies and has certain industrial equipment  
including the production capacity of fuel cell vehicles, and the overall level is gradually in line  
with the international standard. The construction of hydrogen energy-related infrastructure is  
still relatively weak. Most of the hydrogen refueling stations that have been built and are under  
construction are for demonstration purposes, and the verification of economic and long-term  
operation is less. There are only two large hydrogen transportation pipelines, the total length is  
less than 2% of the total length of special hydrogen transportation pipelines in the world, and it  
is still in the initial stage compared with developed countries.  
China’s strategic support for the hydrogen energy industry began in 2006 and has been  
continuously increased in recent years. The National Outlines for Medium and Long-term  
Planning for Scientific and Technological Development (2006—2020) proposes to focus on the  
research of high-efficiency and low-cost hydrogen production technology from fossil fuels and  
renewable energy, cost-effective and efficient hydrogen storage, transportation and  
distribution technology, fuel cell basic key component manufacturing and stack integration  
technology, fuel cell power generation, and vehicle power system integration technology, to  
form technical specifications and standards for hydrogen energy and fuel cells.  
Since 2015, the development of the hydrogen energy and fuel cell industry has been clearly  
proposed in various policies and plans, including Outline of the National Innovation-Driven  
Development Strategy, China Energy Technology Innovation Action Plan (2016—2030),  
National Development Plan for Strategic Emerging Industries during the 13th Five-Year Plan  
Period, Special Plan for Science and Technology Innovation in Transportation Field in the 13th  
Five-Year Plan, and Guiding Catalogue of Key Products and Services in Strategic Emerging  
Industries (Draft for Comments). Many provinces and cities across the country have also  
issued local support policies for the hydrogen energy and fuel cell vehicle industry. In March  
2019, hydrogen energy was included in the Report on the Work of the Government for the first  
time. At the end of 2019, the Energy Statistical Reporting System first included hydrogen in the  
2020 energy statistics.  
According to the forecast of the China Hydrogen Alliance, China’s hydrogen energy industry is  
expected to reach a market scale of RMB 1 trillion from 2020 to 2025 and a market scale of  
RMB 10 trillion from 2036 to 2050. The number of fuel cell vehicles and hydrogen refueling  
stations will increase rapidly, and the technical performance and economic indicators related  
to the utilization of hydrogen energy will continue to improve.  
1.3 Green Hydrogen and Energy Transition  
The climate change issue caused by the excessive application of fossil fuels is the biggest  
crisis facing human beings. It is an urgent task for human beings to significantly reduce fossil  
fuel consumption and greenhouse gas emissions and control temperature rise. For carbon  
emissions related to human activities, the carbon emissions from energy activities account for  
more than 90%. The realization of a clean and low-carbon energy transition is an inevitable  
requirement to respond to the climate and environmental crisis and promote sustainable  
development.  
007  
The Development and Outlook of Green Hydrogen  
In September 2020, during the 75th session of the United Nations General Assembly, Chinese  
President Xi Jinping pledged that China would increase its Nationally Determined Contributions  
(NDCs) and adopt more effective policies and measures to hit peak carbon emissions before  
2030 and realize carbon neutrality before 2060. The realization of carbon emissions peak and  
carbon neutrality is an extensive and profound economic and social systematic green  
revolution, and its essence is to promote comprehensive, high-quality and sustainable  
economic and social development.  
1.3.1 Challenges of Energy Transition  
1. Way of energy transition  
With China Energy Interconnection as the basic platform, the development direction of “Two  
Replacements, One Increase, One Restore and One Conversion” is the only way for the energy  
transition in China and is also the fundamental way to ensure that China will achieve the  
strategic goals of carbon emissions peak before 2030 and carbon neutrality before 2060.  
Clean replacement mainly means replacing fossil fuel with clean energy (such as solar energy  
and wind energy) on the energy supply side for power generation, so as to accelerate the  
formation of an energy supply structure dominated by clean energy. The great development of  
clean energy can not only greatly reduce the greenhouse gas and pollutant emissions caused  
by the combustion of fossil fuels, bring significant environmental benefits, and give full play to  
the huge potential of clean energy resources, but also give full play to the advantage of the low  
marginal cost of clean energy, significantly reduce the economic development cost, accelerate  
the formation of a clean energy-based industrial system, and realize clean and sustainable  
economic and social development. Clean energy consumption is expected to account for 90%  
of primary energy consumption and the installed capacity of clean electricity sources in the  
power system is expected to account for 95% by 2060.  
Electricity replacement mainly refers to replacing coal, oil, and gas with electricity on the  
energy consumption side, so as to get rid of dependence on fossil fuels, thus realizing the  
popularization of modern energy and reducing carbon emissions in the process of energy  
utilization. With the development of electricity technology, electricity replacement has further  
developed, and the final electricity consumption under the “electricity replacement scenario” is  
expected to reach 14,000 TWh by 2060. However, in the chemical industry, metallurgy, aviation,  
and other fields where it is difficult to directly use electricity, it is still required to use coal, oil,  
and natural gas with a total of 1.04 billion tons of standard coal equivalent. By adopting new  
electrification technologies such as power to fuel including power to hydrogen, power to raw  
material, the consumption of electricity will break through the limitations of traditional electricity  
fields, and build an “Electricity + Hydrogen Energy” scenario to realize the indirect substitution  
of clean electricity for end-use of fossil fuels. It is anticipated that the electricity consumption  
throughout society will reach 17,000 TWh by 2060, with an electrification rate of 66%.  
“One Increase” means increasing energy utilization efficiency to promote energy conservation  
and reduce energy intensity. Electricity is an efficient and clean secondary energy, and the  
most effective way to improve energy efficiency is to vigorously promote electrification.  
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Current Situation and Trend of Hydrogen Energy Development  
“One Restore” means restoring fossil fuels to their raw material attributes mainly as industrial  
raw materials to bring about greater economic and social benefits. The restoring process of  
fossil fuels and the development of clean energy complement each other. According to the law  
of economic value, recycling and intensive use of fossil fuels in a more scientific way will  
maximize the realization of resource value to gradually form an ecologically harmonious  
recycling economy development model, thus solving the problem of exhaustion of material  
resources.  
“One Conversion” mainly means the conversion of CO2 and water into fuels and raw materials  
such as hydrogen, methane and methanol by electricity, and the conversion of CO2 from  
mitigation burden to high-value resource through industrial and technological progress such as  
electrochemical technology and carbon recycling, so as to further relieve the resource  
constraints on the survival of human society, expand the broad space for economic growth and  
meet human needs for sustainable development. The new green chemical industry  
represented by the green hydrogen chemical industry is an important development direction  
for the chemical industry to realize technological innovation and break through resource  
constraints.  
2. Challenge of energy transition  
China is the largest developing country in the world, facing arduous development tasks. The  
population and economy will continue to grow in the future. To realize energy transition and  
carbon neutrality, China faces a series of challenges such as large carbon emissions, many  
challenges of industrial upgrading, and difficult adjustment of the energy mix.  
Large total carbon emission and short mitigation time At present, China is the largest carbon  
emitter in the world, with a large amount of greenhouse gas emissions that grows rapidly. In  
2014, the total amount of greenhouse gas emissions was 12.3 billion tons of CO2 equivalent,  
representing an increase of 54% compared with 2005, and the CO2 emissions from energy  
activities accounted for 87% of the total CO2 emissionsA. As the largest developing country  
and the largest emitter, China is faced with the dual challenges of economic and social  
modernization and emission mitigation. It takes only about half the time that is required in  
developed countries from carbon emissions peak to carbon neutrality. The intensity and speed  
of mitigation are unprecedented, and the task of achieving carbon neutrality is arduous.  
There are many challenges in industrial transformation and upgrading. China is currently in the  
critical period for development mode transformation and economic structure optimization and  
growth momentum shift. In 2019, the added value of the secondary industry accounted for 39%  
of GDP, and the proportion of traditional “three highs and one low (high investment, high  
energy consumption, high pollution, and low efficiency)” industries were still high. The added  
value of tertiary industry accounts for 54% of GDP, far below the world average of 65%. In the  
national economy, the secondary industry is the main source of resource consumption and  
pollution emission, especially the energy-intensive industries such as iron and steel, building  
A The People’s Republic of China Second Biennial Update Report on Climate Change, December 2018. The  
greenhouse gas emissions here do not include the carbon sinks absorbed by land use, land-use change  
and forestry.  
009  
The Development and Outlook of Green Hydrogen  
materials, chemicals and non-ferrous metals. More than 60% of China’s energy consumption  
and 70% of its carbon emissions come from the industrial production sector, with industries  
such as iron and steel, building materials and chemicals consuming 75% of the total industrial  
energy consumption. There are lock-in effects and path-dependent effects in the development  
of traditional industries. In order to transform the industrial system based on fossil fuels and  
realize the replacement of traditional fossil fuels with clean energy carriers such as electricity  
and hydrogen, deep, systematic, and fundamental changes are needed in concept, planning,  
technology, and mechanism, etc..  
It is difficult to adjust the energy production mix. Energy activities are the main source of  
carbon emissions, and the CO2 emissions from China’s energy activities account for 87% of all  
CO2 emissionsA. The coal with the highest carbon emission intensity represents 58% of China’s  
energy consumption, and the carbon emissions caused by coal use take up 80% of the total  
emissions, with the prominent feature of “coal occupies the majority.” During the “Thirteenth  
Five-Year Plan” period, China’s clean energy continued to develop rapidly, the scale of  
development continued to expand, the development layout continued to be optimized, and the  
utilization level continued to improve. The installed capacity and the volume of power  
generation of renewable energy ranked first in the world, but there is still space for full  
acceleration. Clean energy accounted for only 15% of primary energy consumption in 2019  
and was lower than the global average figure. Clean energy is primarily for direct end-use in  
the form of electricity, and decarbonization has not been realized in the non-electricity field.  
Decarbonization is hard to be realized in some fields where direct electrification is difficult.  
While vigorously developing electricity replacement and improving the electrification rate of  
end-use energy consumption, there are still some energy consumption fields, such as  
chemical industry, metallurgy, aviation, and industrial high-quality heat, which are difficult to  
realize direct electrification. Direct electrification in aviation, heavy transportation, industrial  
high-quality heat, and other fields has technical challenges, while direct electrification in the  
chemical industry, metallurgy, and other fields cannot achieve industrial carbon neutrality.  
Deep decarbonization in these fields where direct electrification is difficult is the key to  
achieving full carbon neutrality.  
1.3.2 Green Hydrogen and Energy Transition  
Achieving carbon neutrality and clean energy transition in the whole society is the biggest  
driving force for the development of the green hydrogen industry. Zero carbon emission during  
the use of hydrogen can help full decarbonization in the end-use energy fields such as the  
chemical industry, metallurgy, and aviation where it is difficult to directly use electricity and  
hydrogen will play an important role in realizing energy transition and carbon neutrality.  
However, only when hydrogen realizes zero carbon emission at the source can it meet the  
needs of energy transition and low-carbon development. At present, 97% of global hydrogen  
yield comes from hydrogen production from fossil fuels, and carbon emissions remain in the  
production process, so it is impossible to achieve decarbonization by hydrogen production  
from fossil fuels. In the future, green hydrogen will be essential to the hydrogen energy  
industry.  
A Source: The People’s Republic of China Second Biennial Update Report on Climate Change, 2018.  
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Current Situation and Trend of Hydrogen Energy Development  
Green hydrogen is the vital link between clean energy and some end-use energy fields. With  
the continuous deepening of clean transition of the energy system, the process of electricity  
replacement in energy consumption fields such as heating and transportation is gradually  
accelerating, while it is difficult to directly apply electricity to achieve decarbonization in  
aviation, navigation, industrial high-quality heat, chemical industry, metallurgy, and other fields.  
The preparation of green hydrogen by clean electricity can indirectly realize electrification in  
these fields. Hydrogen plays a role as a vital link between clean energy and the end-use  
energy fields where it is difficult to directly use electricity, as shown in Figure 1.3.  
Figure 1.3 Schematic Diagram of the Vital Link of Hydrogen  
Green hydrogen is the central link of the “energy-matter conversion system” . Hydrogen is not  
only energy but also a very significant industrial raw material that is widely used in the chemical  
industry, petrochemical industry, electronics, metallurgy, and other fields. Power to fuel and  
raw material (P2X) technology based on power to hydrogen is an important way for carbon  
reduction in these industries. P2X technology uses water, CO2, nitrogen, and other raw  
materials and clean electricity as the driving force to produce chemical products such as  
methane, methanol, ethylene, benzene, and various materials necessary for human life. At the  
same time, it realizes the solidification and effective utilization of carbon, and further promotes  
the deep decarbonization throughout society. Green hydrogen is not only the link between  
energy production and energy consumption but also helps to realize the deep integration of  
energy systems and social production. Centering on green hydrogen, the demand for  
electricity can be further extended to the traditional chemical industry, so as to realize the  
“non-energy application”A of electricity and establish an “energy-material conversion system”,  
as shown in Figure 1.4.  
A Global Energy Interconnection Development and Cooperation Organization, The Development and Outlook  
of Power Utilization Technologies, China Electric Power Press, Beijing, 2021.  
011  
The Development and Outlook of Green Hydrogen  
Figure 1.4 Schematic Diagram of Energy-matter Conversion System  
Green hydrogen and green electricity are both efficient energy that is available for direct  
end-use, and both stem from clean energy. Green hydrogen is closely connected with green  
electricity, as largely reflected in the following aspects.  
The production of green hydrogen comes from green electricity, both of which are fundamentally  
renewable energy. Renewable energy of the large-scale development substituting fossil fuels,  
either the converted green electricity or green hydrogen, reflects clean energy production. The  
large-scale development and utilization of green hydrogen depend on the progress of  
renewable energy power generation technology and cost reduction. A mature green hydrogen  
preparation system ought to be established on the basis of an economic and efficient  
renewable energy power generation system. At the same time, green hydrogen also sustains  
large-scale development and utilization of renewable energy. Hydrogen and its derived  
synthetic fuels and raw materials are stored with the aid of mature industrial warehousing and  
logistics systems and are expected to work out the “long-period” flexible accommodation  
resource scarcity caused by the seasonal fluctuation of renewable energy in power systems.  
Green hydrogen harmoniously coexists with clean energy power generation and gives strong  
support to the development of renewable energy.  
The utilization of green hydrogen is equivalent to the extension of green electricity, which  
indirectly enhances the end level of electrification. Hydrogen is widely used in aviation,  
navigation, chemical industry, metallurgy, and other fields where electrification is hard to be  
realized. The use of green hydrogen in the substitution of fossil fuels in these fields is  
equivalent to indirect electricity replacement, which can increase the overall demand of the  
end for clean electricity, reduce the carbon emission intensity on the energy consumption side  
and realize the electrification of energy consumption.  
012  
1
Current Situation and Trend of Hydrogen Energy Development  
Green hydrogen and green electricity can be mutually converted, and it is prone to connect to  
establish a zero-carbon energy supply system of multi-energy varieties. Green hydrogen  
comes from electrolyzed water, and can also come from power generated by fuel cells or  
hydrogen fueled gas turbines. Compared with other energy sources, hydrogen energy is easier  
to achieve two-way conversion with electricity. Hydrogen is of a substantial substance and can  
be stored on a large scale conveniently, and there is no need for a strict real-time balance  
between production and consumption. Electricity is a form of energy, with low energy  
consumption and high efficiency in the process of transmission and use. The connection  
between electricity and hydrogen can give full play to their complementary advantages,  
significantly improve the flexibility of the energy system, promote the consumption of  
renewable energy, and meet varied energy demands of ends.  
1.3.3 Green Hydrogen and New Power System  
Green hydrogen will play an important role in the construction of a new power system, and it is  
an important technical solution to realize carbon emissions peak and carbon neutrality.  
Green hydrogen allows significant enhancement of operational flexibility of power system. With  
the rapid expansion of the installed capacity proportion of wind and solar energy-based  
fluctuating renewable energy, the uncertainty on both sides of source and load will be clearly  
on the rise, which will bring increasing flexibility demand for daily, monthly and seasonal  
fluctuation, especially if there is a differential between the monthly electricity distribution and  
load demand, there will be a problem of seasonal electricity balance, which cannot be  
solved by general energy storage technology. Electrolytic hydrogen production technology  
can provide flexibility of time scale from a second to a minute under different technical  
routes. The storage of hydrogen and its derived synthetic fuels and raw materials with the  
aid of mature industrial warehousing and logistics systems can also provide flexible  
adjustment capability of large time scale, and work out the “long-period” flexible adjustment  
resource scarcity caused by the seasonal fluctuation of renewable energy in power systems.  
In addition to the direct end-use of energy of hydrogen and its derived synthetic fuels, the  
excess part is for long time storage and is converted into electricity again by power  
generation equipment such as fuel cells or gas turbines in case of an electricity lack in the  
power system, so it is easier to realize large-scale long-term energy storage than direct  
electricity storage. In 2060, China’s electricity consumption for hydrogen production is  
expected to account for 20% of the total electricity consumption throughout society and thus  
contains great flexibility potential.  
Green hydrogen can improve the supply guarantee ability of the power system. The confidence  
capacity of the wind and solar electricity sources is low, with a large gap between the minimum  
output and the actual capacity. The minimum daily average output level of renewable energy in  
China’s provinces and regions was 3.6% and 8.0% respectively, and the minimum  
instantaneous output level of renewable energy was 0.2% and 1.1% respectively in 2019. The  
wind power generation in Northeast China hit a record low of 34,000 kilowatts on July 28, 2021,  
which is less than 0.1% of the installed capacity of wind power. With the increasing proportion  
of wind and solar installed capacity, the power generation efficiency is prominent, but the  
capacity efficiency is weak, especially when the risk increases under extreme weather impact,  
the power supply support capability of the system is facing great challenges. Hydrogen energy  
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The Development and Outlook of Green Hydrogen  
stores electricity in material form, which has the advantages of long storage time, high energy  
density, and convenient conversion between electricity and hydrogen. Under the condition of  
tight system supply, hydrogen fueled gas turbine and hydrogen fuel cell on the supply side can  
output electricity, and a load of electrolytic hydrogen production can be accommodated on the  
load side, thus providing a guarantee for power supply.  
Green hydrogen can provide support for the security and stability of the power system. With  
the continuous growth of wind-solar electricity sources and inter-regional DC interconnection,  
the power electronics dominated power system has become an inevitable trend. The unit  
based on power electronic devices has low inertia, weak immunity, and low terminal voltage.  
After connecting to the power grid with step by step voltage boosting, the electrical distance  
from the main grid is 2-3 times that of conventional units and will lead to severe challenges to  
the frequency and voltage stability of the power system. New problems such as broadband  
oscillation will also become hidden dangers due to weak voltage support and insufficient  
short-circuit ratio of the AC system. The hydrogen fueled gas turbine is a synchronous  
generator with high output controllability, high ramp rate, strong frequency regulation, and  
voltage support capability, and can be used as a safe and stable supporting electricity source  
for the system after the conventional coal-fired power units are out of service.  
1.4 Reporting Ideas and Main Contents  
The research is carried out in the report from three angles of demand, production, and  
allocation, combined with different links of the hydrogen industry chain. First of all, the report  
sorted out the key technologies of hydrogen production, hydrogen storage and transportation,  
and hydrogen utilization, and completed the technical research and identification and  
cost-effectiveness projection. Based on the economic and social development, energy  
system transition, and energy demand of various industries, combined with hydrogen  
technology and economic evaluation of various industries, the future demand for green  
hydrogen in China is predicted. Based on the research results of GEIDCO in the clean  
energy power generation technology and global clean resource assessment fields,  
combined with hydrogen technology and economic evaluation of various industries, the  
development potential and cost distribution of green hydrogen in China are quantitatively  
assessed. In this report, an overall optimization analysis model for the electricity-hydrogen  
zero-carbon energy system is built, and the long-distance and large-scale green hydrogen  
allocation optimization scheme combining the hydrogen transportation through pipelines  
with the replacing hydrogen transportation with power transmission is preliminarily proposed  
based on different transportation scenarios. The research ideas and main research contents of  
the report are shown in Figure 1.5.  
Research on key technologies. In terms of hydrogen production technology, the report sorts  
out hydrogen production technology routes such as hydrogen production by water electrolysis,  
hydrogen production from fossil fuels, and industrial by-product hydrogen and compares the  
cost, efficiency, carbon emission, and technical stages of various hydrogen production  
technologies, and introduces in detail the difficulties and R&D directions of green hydrogen  
production technology. The report indicates that clean and zero-carbon “green hydrogen”  
represented by electrolytic hydrogen production based on renewable energy leads to the most  
important development direction of hydrogen production technology in the future.  
014  
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Current Situation and Trend of Hydrogen Energy Development  
Figure 1.5 Research Ideas and Main Research Contents of the Report  
In terms of hydrogen storage and transportation technology, the massive hydrogen production  
industry and diversified end-use in the future need the support of hydrogen storage and  
transportation technology. The report sorts out hydrogen storage technologies of gaseous,  
liquid, solid, and chemical states, etc.. and hydrogen transportation technologies of the  
pipeline, land, and waterway, etc.; compares the hydrogen storage density, hydrogen storage  
mass fraction, environmental requirements, technical stages, energy consumption and energy  
efficiency of various hydrogen transportation technologies; and proposes the R&D direction of  
hydrogen storage and hydrogen transportation technologies. The report analyzes the most  
appropriate hydrogen transportation technology in various scenarios and points out that  
hydrogen transportation through pipelines and replacing hydrogen transportation with power  
transmission are important ways to realize large-scale long-distance hydrogen-energy  
transmission on land.  
In terms of hydrogen utilization technology, hydrogen will play an important role in the future  
energy transition and is not only conducive to decarbonization in the field where direct  
electrification is difficult and but also be in favor of the development of a high proportion of  
renewable energy. In order to answer the questions about the application field and scale of  
hydrogen in the future carbon neutrality energy system, the report systematically sorts out the  
application of hydrogen in energy, transportation, chemical industry, metallurgy, and other  
industries, compares and analyzes the hydrogen utilization technology and direct  
electrification technology in transportation, metallurgy, heating, and other fields, and  
introduces the difficulties and R&D direction of hydrogen utilization technology.  
Green hydrogen demand projection and development potential evaluation: The application  
scenario and demand projection of green hydrogen are some of the key issues of the green  
hydrogen industry. From the perspective of economic and social development and energy  
transition, combined with the energy demand of various industries and the technical and  
015  
The Development and Outlook of Green Hydrogen  
economic research and identification of potential hydrogen utilization fields, the report makes a  
technical judgment on the application scale and development stage of green hydrogen in  
future energy, industry, transportation, construction, and other fields, and describes the  
application prospect of green hydrogen. In order to promote the deep decarbonization of the  
whole industry, the future “hydrogen source” is bound to be majority-green hydrogen with zero  
carbon emission, and the assessment of green hydrogen resources is the basis of hydrogen  
energy application. Relying on the “Global Renewable-energy Exploitation Analysis Platform  
(GREAN)” developed by the Global Energy Interconnection Development and Cooperation  
Organization (GEIDCO), the report constructs a set of evaluation algorithms and optimization  
models of green hydrogen preparation potential and cost, calculates the global green hydrogen  
preparation potential, obtains the cost optimization map, and makes a detailed analysis of  
China’s regions rich in green hydrogen resources and with excellent cost-effectiveness.  
Research on the electricity-hydrogen coordinated zero-carbon energy system: The geographical  
relationship between clean energy and energy demand in China is characterized by reverse  
distribution. Like green electricity, green hydrogen needs large-scale long-distance transportation  
from production base to demand center. Green hydrogen comes from green electricity,  
together with which constitutes the main body of the zero-carbon energy system and should be  
optimized as an important part of the energy system. The report constructs an energy system  
of connection between electricity and hydrogen, including the technical models of production,  
transportation, and storage of green electricity and green hydrogen. With the goal of the best  
cost-effectiveness of the whole system, all elements of source, grid, load, and storage are  
optimized. On the basis of meeting the demand for green hydrogen, a series of questions such  
as “where is green hydrogen exploited”, “transmission of electricity or hydrogen molecules”  
and “impacts of green hydrogen exploitation and utilization on power system” are answered,  
and systematic value of diversified energy transmission is analyzed. Based on the research  
results of GEIDCO, the report studies the optimal layout and allocation plan of renewable  
energy development, power flow, and hydrogen transportation through pipelines under the  
scenario of China Energy Interconnection in 2060, and analyzes the comprehensive value of  
electricity-hydrogen coordinated allocation.  
016  
2
Key Technologies for Green Hydrogen  
Key Technologies for  
Green Hydrogen  
The Development and Outlook of Green Hydrogen  
Hydrogen production, hydrogen storage and transportation, and hydrogen  
utilization are three key technologies of green hydrogen, and solving the related  
technical and economic problems in these three links is the key to the  
development of the hydrogen industry. At present, the green hydrogen  
production technology is relatively mature and the cost-effectiveness needs to  
be improved. Hydrogen storage and transportation technology is facing  
challenges and a lack of experience in large-scale storage and transportation.  
The application potential of green hydrogen has yet to be tapped, and related  
industries are still in the start-up stage. This chapter introduces various  
hydrogen production technologies, hydrogen storage and transportation  
technologies, and the application of hydrogen in energy, transportation,  
chemical industry, and other industries, analyzes the application fields of green  
hydrogen combined with the requirements of carbon neutrality and energy  
transition and puts forward the development path of green hydrogen production,  
storage and transportation technologies to reduce costs and improve efficiency.  
2.1 Hydrogen Production Technology  
There are many technical routes for hydrogen production, including hydrogen production by  
water electrolysis, hydrogen production from fossil fuels, industrial by-product hydrogen, etc..  
At present, the global hydrogen production industry is dominated by grey hydrogen prepared  
from fossil fuels as raw material, while hydrogen production by water electrolysis accounts for a  
small proportion. With the reduction of the cost of renewable energy power generation and the  
concern of environmental problems and carbon emissions, the green technology of hydrogen  
production by water electrolysis has attracted more and more attention.  
2.1.1 Current Technical Status  
Hydrogen generally needs to be extracted from compounds such as water and natural gas.  
The preparation methods of hydrogen primarily include hydrogen production by water  
electrolysis, hydrogen production from fossil fuels, industrial by-product hydrogen, hydrogen  
production from biomass, and hydrogen production by water photolysis.  
At present, the vast majority of hydrogen in the world comes from fossil fuels sources such as  
natural gas, oil, and coal, among which less than 1% of hydrogen yield comes from renewable  
energy— hydrogen production by water electrolysis (namely green hydrogen) or hydrogen  
production from fossil fuels equipped with CCUS equipment (namely blue hydrogen), and a  
large amount of grey hydrogen production causes about 830 Mt of yearly CO2 emissions.  
China’s hydrogen production from coal has a proportion of more than 60%, while that of  
018  
2
Key Technologies for Green Hydrogen  
hydrogen production by water electrolysis accounts for only 1%-1.5%, as shown in Figure 2.1.  
Figure 2.1 Sources of Hydrogen in China  
2.1.1.1 Hydrogen Production by Water Electrolysis  
Hydrogen production by water electrolysis refers to the technology of using electricity to split  
water into hydrogen and oxygen. This reaction takes place in the electrolysis cell and is an  
inverse reaction with hydrogen fuel cell power generation. Water electrolysis consists of two  
semi-reactions, i.e., hydrogen evolution reaction on the cathode and oxygen evolution reaction  
on the anode, with the reaction formula shown as follows:  
Cathode: 4H+ + 4e− = 2H2 (acid)  
4H2O + 4e− = 2H2 + 4OH− (alkaline)  
Anode: 2H2O − 4e− = 4H+ + O2 (acid)  
4OH− − 4e− = 2H2O + O2 (alkaline)  
The main technologies of hydrogen production by water electrolysis include alkaline electrolysis  
cell (AEC), proton exchange membrane (PEM) electrolysis cell, and high-temperature solid  
oxide electrolysis cell (SOEC).  
1. Alkaline electrolysis cell  
Hydrogen production by alkaline electrolysis cell is the most conventional and technically  
mature way of electrolytic hydrogen production and has a fast start-stop speed (minute level),  
and full power adjustment capability, is the current mainstream method of hydrogen production  
by water electrolysis, with the disadvantage of low efficiency (about 70%).  
The principle of hydrogen production by alkaline water electrolysis is that a pair of electrodes is  
inserted into an electrolysis cell containing an alkaline electrolyte, and a direct current of a  
certain voltage is applied to split water into hydrogen and oxygen. The alkaline electrolyte is  
generally prepared by 20%-30% KOH or NaOH aqueous solutions, with asbestos as an  
interlayer. The electrode material is the key element that affects electrolysis efficiency. In  
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The Development and Outlook of Green Hydrogen  
industrial production, it is required that the hydrogen evolution cathode can work intermittently  
for a long time under the conditions of high temperature, high alkali concentration, and high  
current density. Based on the observations of stability and cost, iron and nickel alloy are mainly  
used as cathode materials in the alkaline electrolysis cell, and nickel, cobalt, and iron as the  
anode materials. The operating temperature of a commercial alkaline electrolysis cell is  
70-80°C, the electrolysis voltage is about 1.8VA , and the unit energy consumption is  
approximately 57kWh/kg (5kWh/m3).  
In recent years, the manufacturing technology of alkaline electrolysis cell in China has  
developed rapidly, with the localization rate reaching 95% and the cost dropping significantly.  
The equipment cost of an alkaline electrolysis cell is at the scope of RMB 1400−2000/kW. There  
is still a certain gap between the membrane and electrode technology level of domestic  
equipment and that of foreign equipment, but the domestic products have a distinct cost  
advantage.  
2. PEM electrolysis cell  
In the PEM technology, organic membranes that can only be penetrated by protons are used to  
replace membranes and liquid electrolytes in conventional alkaline electrolysis cell, and at the  
same time, noble metal catalysts with high activity are pressed on both sides of the PEM, thus  
effectively reducing the volume and resistance of the electrolysis cell, and improving the  
electrolytic efficiency to about 80%. Meanwhile, the power accommodation is more flexible  
(second level), but the equipment cost is relatively high. The structure of the typical PEM  
electrolysis cell is shown in Figure 2.2.  
Figure 2.2 Schematic Diagram of Structure of PEM Electrolysis Cell  
A Zhang Kaiyue, et al., Research Progress on Hydrogen Evolution by Alkaline Water Electrolysis - Electrode.  
Chemical Industry and Engineering Progress, 2015.34(10): p.3680 - 3687 + 3778.  
020  
2
Key Technologies for Green Hydrogen  
The PEM is the heart part of the PEM electrolysis cell and it not only conducts protons and  
splits hydrogen and oxygen, but also provides certain support for anode and cathode catalysts  
to ensure the operation of the electrolysis cell. PEM should have excellent stability and good  
proton conductivity; besides, the membrane surface should have good compatibility with  
catalyst and can effectively prevent gas diffusion. At present, DuPont’s Nafion membrane is the  
most widely used membrane. In the membrane electrode structure of PEM, since Nafion  
membrane has strong acidity in water, it requires high corrosion resistance and stability of  
electrode materials, and electrode materials should also have an excellent catalytic  
performance to improve electrolysis efficiency. The electrode material of the PEM electrolysis  
cell is usually made of a noble metal catalyst, with platinum-carbon (Pt/C) catalyst for the  
cathode, iridium oxide (IrO2), or ruthenium oxide, etc.. (RuO2) for the anode. The use of noble  
metal catalysts is an important factor to drive up the cost of PEM electrolysis cells, so it is an  
important research direction regarding PEM to reduce the noble metal load or exploit low-cost  
non-noble metal catalysts.  
3. High-temperature SOEC  
High-temperature SOEC is born out of fuel cell technology and can be regarded as the reverse  
operation of solid oxide fuel cell (SOFC). It is characterized in that at a high temperature  
(600-1000°C), the thermodynamic and kinetic characteristics of electrolysis reaction are  
improved, so the electrolysis efficiency can be raised to around 90%. At present, this  
technology is still in the stage of a commercial demonstration.  
The currently developed high-temperature SOECs can be classified into oxygen ion-conducting  
SOEC and proton-conducting SOEC according to different electrolyte carriers, as shown in  
Figure 2.3. Typically, an SOEC electrolysis cell predominantly consists of electrolyte, anode  
(also called oxygen electrode), and cathode (also called hydrogen electrode). There is a  
dense electrolyte layer assembled between two porous electrodes (an anode and a cathode)  
in the electrolysis cell. The electrolyte acts as a separator to prevent a direct reaction between  
the fuel and oxidant and conduct oxygen ions or protons. In general, the electrolyte is required  
to be compact and have high ionic conductivity and negligible electronic conductivity.  
Generally, the electrode is made into a porous structure to increase the three-phase interface  
of electrochemical reactions and facilitate the diffusion and transmission of gas.  
Figure 2.3 Schematic Diagram of Principle of Oxygen Conducting and Proton Conducting SOEC  
021  
The Development and Outlook of Green Hydrogen  
Three technologies of hydrogen production by water electrolysis are compared in Table 2.1.  
The current technology of alkaline electrolysis cell is the most mature and cheap, but with low  
electrolysis efficiency; PEM electrolysis cell technology has the fastest response capability and  
the highest power density, but high equipment cost, so it can be used in scenes with higher  
requirements on equipment volume and accommodation capability; high-temperature SOEC  
technology has the highest electrolytic efficiency, but relatively short service life, and moreover,  
it is still in the R&D and demonstration stage.  
Table 2.1 Comparison of Characteristics and Parameters of Three  
Technologies for Hydrogen Production by Water Electrolysis  
High-temperature  
SOEC  
electrolysis bath  
Alkaline electrolysis  
cell  
PEM  
electrolysis bath  
Technical link/parameter  
Operation temperature  
Unit  
℃
600-1000  
about 25  
70−80  
60−80  
Unit hydrogen  
production scale  
m3/h  
0.5−1000  
0.01−300  
Electricity consumption  
for hydrogen production  
kWh/m3  
%
4.7−5.5  
3.9−5  
2.6−3.6  
Electrolytic efficiency  
Response capability  
Service life  
65−75  
Minute  
70−80  
85−100  
Minute  
Second level  
10−20 years  
~10,000h  
20−30 years  
Commercial  
application  
Commercial  
application  
In the demonstration  
stage  
Technical stage  
Price of electrolytic cell  
RMB/kW  
1500−5000  
10,000−20,000  
—
4. Cost-effectiveness analysis of hydrogen production by water electrolysis  
The cost of hydrogen production by water electrolysis mainly consists of three parts: electricity  
cost, construction investment cost, and OPEX. The expenditure on electricity is the major cost  
of hydrogen production by water electrolysis, accounting for roughly 79%, including electricity  
fee, transmission, and distribution capacity fee, loss, and other additional costs, among which  
electricity fee is the major expenditure item. By taking the current commercial hydrogen  
production system with a single-electrode alkaline electrolysis cell as an example, the electricity  
fee accounts for about 80% of the electricity cost and 63% of the total cost, as shown in Figure 2.4.  
Figure 2.4 Structure of Hydrogen Production Cost in Single-electroAlkaline Electrolysis Cell  
022  
2
Key Technologies for Green Hydrogen  
The construction investment cost mainly contains the initial investment of stack, powerhouse,  
power grid access equipment, and other additional equipment, as well as the subsequent  
interest repayment. The cost of hydrogen production equipment is closely related to the  
manufacturing process level, and the increase of equipment scale and yield can reduce the  
unit cost of equipment. By taking the alkaline electrolysis cell of Norway’s NEL as an example,  
when the installed capacity exceeds 10,000kWh, the change of unit kilowatt investment tends  
to be stable, as shown in Figure 2.5. With the continuous expansion of the hydrogen production  
scale in the future, the equipment cost is expected to decline rapidly.  
Figure 2.5 Unit Investment of Alkaline Electrolysis Cell  
The annual OPEX comprises equipment OPEX, insurance cost, labor cost, etc., and is  
generally about 5%-9% of the construction investment cost.  
The primary factors that affect the electrolytic hydrogen production cost include electricity  
price, conversion efficiency, equipment scale, equipment utilization rate, and so on. The cost  
of hydrogen production by water electrolysis is extremely sensitive to the electricity price. If the  
electricity price is reduced by half, the electrolytic hydrogen production cost will be reduced by  
one-third, as shown in Figure 2.6. According to the investigation results, taking the domestic  
hydrogen production system of alkaline electrolysis cell as an example, the calculation shows  
that the cost of hydrogen production is RMB 21−25/kg when the electricity price is RMB  
0.35/kWh. At present, the cost of clean energy power generation is reducing continuously. If  
the electricity price drops to RMB 0.25/kWh, the cost of hydrogen production by electrolysis  
calculated with the price of electrolyzed water equipment will drop to RMB 15/kg, which is  
close to the current cost of hydrogen production from fossil fuels.  
Conversion efficiency affects the unit power consumption of hydrogen production, and the cost  
of hydrogen production can be effectively lowered by improving electrolysis efficiency through  
technological innovation. At present, the efficiency of hydrogen production in mainstream  
alkaline electrolysis cell is about 70%, and the power consumption of hydrogen production is  
about 57kWh/kg. It is anticipated that by 2050, new electrolytic hydrogen production  
technologies such as high-temperature SOEC are expected to become the mainstream, which  
will lead to an increase of the electrolysis efficiency from 70% to 90%, and the electricity  
023  
The Development and Outlook of Green Hydrogen  
consumption per kilogram of hydrogen will be dropped to about 45kWh, which is equivalent to  
a 21% reduction in electricity cost when the electricity price remains unchanged.  
Figure 2.6 Relationship between Cost of Hydrogen Production by  
Water Electrolysis and Electricity Price  
When the electricity price remains unchanged, the larger the scale of electrolyzed water  
equipment, the lower the hydrogen production cost, and the proportion of annual construction  
investment cost in the total cost gradually drops. Taking the alkaline electrolysis cell as an  
example, the hydrogen production cost of a 46 MW (20-electrode) stack is 88% of that of a  
2.3MW (single-electrode) stack, as shown in Figure 2.7.  
Figure 2.7 Relationship between Cost of Hydrogen Production by  
Water Electrolysis and Equipment Scale  
The above-mentioned cost analysis is based on the premise of full power operation of the  
hydrogen production equipment in the whole period, that is, an annual utilization rate of 100%  
(8760hrs a whole year). The hydrogen production cost is significantly negatively correlated with  
the utilization rate, especially after the utilization rate is lower than 40% (3500hrs a year), the  
cost increases significantly with the decrease in utilization rate, as shown in Figure 2.8.  
024  
2
Key Technologies for Green Hydrogen  
Figure 2.8 Relationship between Cost of Hydrogen Production by  
Water Electrolysis and Equipment Utilization Rate  
With the clean energy transition in the future, electricity mainly comes from clean energy such  
as wind energy and solar energy, which have strong randomness and fluctuation. If the  
function of electrolytic hydrogen production as a controllable load or even energy storage is to  
be exerted, the utilization rate of hydrogen production equipment will be closely related to the  
output characteristics of clean energy power generation and the load characteristics of power  
grid, which is expected to be generally around 40%.  
5. Application of hydrogen production by water electrolysis  
Alkaline water electrolysis technology was put into use as early as the 1920s, and it is still the  
mainstream technology of hydrogen production by water electrolysis. In the 1960s, General  
Electric Company introduced the PEM electrolysis cell system for the first time, but it has not  
been widely promoted at present due to service life, cost, and other factors. The SOEC is still in  
the demonstration stage. The application of some domestic and overseas commercial water  
electrolysis devices is shown in Table 2.2.  
Table 2.2 Application of Some Domestic and Overseas Commercial Water Electrolysis Devices  
Hydrogen  
production Power consumption  
Electrolytic  
efficiency  
(%)  
Area  
Developer  
Type of device  
Type  
capacity  
(kWh/m3)  
(m3)  
Hydrogenics  
NEL Hydrogen  
IHT  
HySTAT type V  
NEL-A  
AEC  
AEC  
AEC  
AEC  
10-60  
50-485  
3-27  
5.2-5.4  
4.3-4.5  
4.3-4.6  
5.3  
65-68  
79-81  
77-82  
67  
Type S  
HT Hydrotechnik  
EV  
24.6-250  
TELDYNE ENERGY  
SYSTEM  
Titan EC  
FuelGen C  
HHOC  
PEM  
PEM  
PEM  
28-42  
10-30  
1-60  
5.6-6.4  
5.8-6.2  
6.5  
55-64  
57-61  
54  
Foreign  
Proton Onsite  
KOBELCO  
ECO-SOLUTIONS  
Ceram Hyd  
Siemens  
CH  
PEM  
PEM  
30-200  
22.4  
5
71  
80  
Silyzer100  
4.4  
025  
The Development and Outlook of Green Hydrogen  
continued  
Hydrogen  
production Power consumption  
Electrolytic  
efficiency  
(%)  
Area  
Developer  
Type of device  
Type  
AEC  
AEC  
capacity  
(kWh/m3)  
(m3)  
Suzhou Jingli  
—
—
2-1000  
5-500  
5
71  
80  
Suzhou Guoneng  
Shengyuan Hydrogen  
Equipment  
4.4  
Technology Co., Ltd.  
Yangzhou Zhongdian  
Hydrogen Production  
Equipment Co., Ltd.  
—
—
—
AEC  
AEC  
AEC  
20-1000  
1-600  
4.5  
4.6  
4.4  
78  
77  
80  
Domestic  
The 718th Research  
Institute of CSSC  
Tianjin Mainland  
Hydrogen Equipment  
Co., Ltd.  
0.1-1000  
Chunhua Hydrogen  
Energy Technology  
Limited Company  
—
PEM  
10-50  
4.8-5.0  
71-74  
Box 2.1  
Planning of Global Green Hydrogen Projects  
Green hydrogen has great application potential in industries, transportation, and other  
fields, but the green hydrogen preparation industry is still an emerging industry, and  
most of the present green hydrogen projects in operation are at 10MW and 100MW  
scales. Based on the observations of the huge demand anticipation for hydrogen energy  
and economies of scale, many countries have planned the green hydrogen projects of  
GW scale, some of which are listed in the following table.  
Box 2.1 Table Some GW-scale Green Hydrogen Planning Projects in the World  
Hydrogen  
output  
(10,000  
Installed  
capacity  
Project  
completion  
time  
Project name  
Location  
Remarks  
(GW)  
tons/year)  
Powered by 95GW solar  
Before 2030 energy for hydrogen  
Western  
Europe  
HyDeal Ambition  
67  
360  
—
supply in Europe  
Powered by 30GW wind  
energy and solar energy;  
hydrogen is used in  
green steel and other  
fields.  
Northern  
Mauritania  
AMAN Power2X  
20  
—
026  
2
Key Technologies for Green Hydrogen  
continued  
Hydrogen  
output  
(10,000  
Installed  
Capacity  
Project  
completion  
time  
Project name  
Location  
Remarks  
(GW)  
tons/year)  
Powered by 16GW  
onshore wind power and  
10GW solar energy  
power and exported to  
Asian countries  
Asian Renewable  
Energy Hub  
Western  
Australia  
14  
175  
100  
100  
50  
2028  
2040  
2035  
2021  
Powered by offshore wind  
power, used in Dutch and  
German heavy industries,  
at the stage of the  
feasibility study and  
expected to reach 1GW  
in 2027  
Northern  
Netherlands  
NorthH2  
>10  
10  
5
Powered by offshore wind  
power, at the initial stage  
of the project and  
expected to reach 30MW  
in 2025  
Heligoland,  
Germany  
AquaVentus  
Inner Mongolia  
Wind, Solar,  
Hydrogen, and  
Storage Integrated  
Project of Beijing  
Jingneng Power Co.,  
Ltd.  
Ergun banner,  
Inner  
Mongolia  
Under construction  
Powered by onshore wind  
power and solar power  
for export  
Northwest  
Saudi Arabia  
Helios Green Fuels  
Base One  
4
24  
60  
—
Powered by wind power  
and solar power; the  
project was announced in  
2021 for export  
Northeast  
Brazil  
3.4  
2025  
Powered by solar energy,  
used for green fertilizer  
production and export;  
the project was  
announced in 2020 and is  
in the initial stage  
HyEx  
1.6  
1.5  
Chile  
12.4  
25  
2030  
2029  
Powered by solar energy,  
mainly used for fuel cell  
power generation, as well  
as for heating and heavy  
industry  
Northern  
Greece  
White Dragon  
027  
The Development and Outlook of Green Hydrogen  
6. Water for electrolytic hydrogen production and seawater desalination  
Water is the main raw material for electrolytic hydrogen production. With the rapid development  
of the hydrogen energy industry, the water source is also one of the key factors to be  
considered in the development of green hydrogen.  
The theoretical water consumption of electrolytic hydrogen production is at least 9kg/kg  
(water/hydrogen). Taking into account the demineralization loss of water in the actual  
production process, the product hydrogen and oxygen will take away some water vapor, so the  
actual water consumption is about 20kg/kg (water/hydrogen). It is estimated that by 2050, the  
global electrolytic hydrogen production will reach 340 Mt per year and the water consumption  
will be nearly 7 billion m3. Compared with the current global annual agricultural water  
consumption of 2.8 trillion m3, industrial water consumption of 800 billion m3 and nearly 500  
billion m3 of water consumption in cities and urban areas, in general, the water consumption of  
electrolytic hydrogen production is not great.  
For coastal areas with sufficient wind and solar resources but limited freshwater resources  
such as West Asia, North Africa, and northern Chile in South America, direct electrolysis  
seawater technology or seawater desalination technology is required to be considered to  
develop the electrolytic hydrogen production industry. Compared with fresh water electrolysis,  
seawater electrolysis has problems such as possible precipitation of chlorine gas from the  
anode, easy generation of calcium magnesium ions, increased resistance, easy corrosion of  
the membrane, etc.. There is no large-scale industrial application for seawater electrolysis.  
Under the condition that the seawater electrolysis technology is not yet mature, seawater  
desalination can be used to pretreat the electrolysis cell water. Taking the reverse osmosis now  
commonly used as an example. The power consumption of seawater desalination is about  
3kWh/m3, and the cost is generally RMB 3.5-7/m3. Considering the short-distance  
transportation cost of water supply and the treatment cost of concentrated brine generated  
from seawater desalination, the water cost for electrolytic hydrogen production in this scenario  
is about RMB 10 - 14 / m3. The application of seawater desalination technology will increase the  
power consumption of electrolytic hydrogen production by 0.06kWh/kg hydrogen, accounting  
for only one thousandth of the total power consumption of electrolytic hydrogen production.  
Increase the cost of electrolytic hydrogen production by RMB 0.2-0.3/kg, accounting for about  
1% of the cost of electrolytic hydrogen production. Therefore, the application of seawater  
desalination technology has little impact on the energy consumption and cost of electrolytic  
hydrogen production, and the limitation of fresh water resources will not become the bottleneck  
of electrolytic hydrogen production industry in West Asia, North Africa, northern Chile, and  
other regions. The cost composition of electrolytic hydrogen production considering seawater  
desalination is shown in Figure 2.9.  
2.1.1.2 Hydrogen Production from Fossil Fuels  
At present, the vast majority of hydrogen in the world comes from natural gas, oil, coal and  
other fossil fuels, and the technical means include steam reforming, partial oxidation reforming,  
coal gasification and so on.  
028  
2
Key Technologies for Green Hydrogen  
Figure 2.9 Cost Structure of Electrolytic Hydrogen Production Considering Seawater Desalination  
1. Hydrogen production from natural gas  
Hydrogen production from natural gas is the most important technical route of hydrogen  
production in the world. After desulfurization, dechlorination and arsenic removal, natural gas is  
transformed by high-temperature steam or partially oxidized under the action of a nickel  
catalyst to produce H₂ and CO₂. Natural gas is used as both a fuel (about 30%) and a  
hydrogen source, enabling the extraction of methane and hydrogen from water. The cost of raw  
natural gas is the largest cost expenditure in hydrogen production from natural gas,  
accounting for about 45% to 75% of the total cost. The gas price in North America, Russia and  
the Middle East is relatively low, and the cost of hydrogen production from natural gas is  
generally around RMB 7-10/kg(USD 1-1.5/kg). The cost of hydrogen production from natural  
gas in China is about RMB 15-16/kg. The CO2 emission of hydrogen production from natural  
gas is generally 9-11 times that of hydrogen production. Considering the cost of CO2 emissions  
(in terms of RMB 50/tA), the cost of hydrogen production from natural gas in China is about  
RMB 16-17/kg.  
2. Hydrogen Production by Partial Oxidation of Heavy Oil  
Hydrogen production by partial oxidation of heavy oil generates hydrogen, carbon monoxide  
and carbon dioxide through the reaction of heavy oil with oxygen and steam. This process is  
carried out at a certain temperature and pressure, with or without catalysts according to the  
selected raw materials and processes. Compared with hydrogen production by methane, the  
hydrocarbon ratio of heavy oil is higher, so the hydrogen produced by partial oxidation of  
heavy oil comes more from steam (about 70%) Bthan from heavy oil itself, that is, heavy oil is  
more used as fuel to maintain the temperature and heat required in the reaction process.  
Generally speaking, the cost of raw materials accounts for about one-third of the cost of  
hydrogen production by partial oxidation of heavy oil. Other costs mainly include equipment  
A According to the transactions of the national carbon market, the transaction price of the carbon emission  
quota is RMB 44.08 per ton.  
B Wang Dongjun, et al., Research Progress of Industrial Hydrogen Production Technology at Home and  
Abroad. Industrial Catalysis, 2018. 26(05): p. 26-30.  
029  
The Development and Outlook of Green Hydrogen  
investment, operation cost, etc.. Usually, equipment investment costs account for a relatively  
large proportion. When the crude oil price is USD 40-100/barrel, the cost of hydrogen production  
by partial oxidation of heavy oil is RMB 8-17/kg, and the carbon emission is higher than that of  
hydrogen production by natural gas. Considering the cost of CO2 emissions (in terms of RMB  
50/t), the cost of hydrogen production from heavy oil in China is about RMB 9-18/kg.  
3. Hydrogen production by coal gasification  
Hydrogen production by coal gasification mainly includes two processes: gasification reaction  
and water gas shift reaction. The gasifier is the core equipment. Different process conditions,  
mass transfer, and heat transfer modes have a great influence on the reaction rate and degree  
of the coal gasification process. The technology of hydrogen production by coal gasification is  
relatively mature. At present, more than 80% of the global hydrogen production plants by coal  
gasification are located in China. Based on China’s energy endowment of “rich in coal but poor  
in oil”, hydrogen production from coal is the lowest cost method at present, which can be as  
low as RMB 7-10/kg when the coal price is RMB 350-500/t, of which the cost of coal accounts  
for 30%-40%. However, the CO2 emissions intensity of hydrogen production from coal is higher,  
and the CO2 emissions are about 20 times that of hydrogen production and twice that of  
hydrogen production from natural gas. Considering the CO2 emissions cost (calculated by  
RMB 50/t), the cost of hydrogen production from coal in China is about RMB 8-11/kg.  
4. Hydrogen production from fossil fuels+CCUS technology  
Hydrogen production technology from fossil fuels is mature and low cost, but with the serious  
carbon emission problem, it is contrary to the concept of low-carbon development, and it also  
gives a ray of “grey” to hydrogen energy. The application of carbon capture, utilization and  
storage technology (CCUS) in hydrogen production from fossil fuels can reduce carbon  
emissions by more than 90% and realize the production of blue hydrogen. Application of CCUS  
technology will increase the cost of hydrogen production from fossil fuels by about 30%-50%.  
The typical hydrogen production process of natural gas steam reforming with carbon capture  
technology is shown in Figure 2.10.  
Figure 2.10 Schematic Diagram of Hydrogen Production Process by Steam  
Reforming of Natural Gas with Carbon Capture Technology  
030  
2
Key Technologies for Green Hydrogen  
2.1.1.3 Industrial by-product hydrogen  
As for industrial by-product hydrogen, there is no relevant normative explanation in current  
national standards. According to the definition of industrial by-products and following the  
principles of economy and environmental protection, industrial by-product hydrogen mainly  
comes from the following three areas: Coking, Chlor-alkali Production and Propane  
Dehydrogenation. The output of by-product hydrogen mainly depends on the output of main  
products in its field.  
The by-product hydrogen of coking industry comes from the coking process, which cools the  
coke by spraying water to the high-temperature coke, and the high-temperature coke reacts  
with water to release a large amount of hydrogen. Hydrogen content in wet coke oven gas is  
generally 55%-60%. With the popularization of zero-carbon metallurgical technologies such as  
hydrogen metallurgy and electrometallurgy in the future, and the popularization of dry  
quenching technology in coking industry, the scale of this part of by-product hydrogen will  
show a downward trend in the future. In addition, the purity of coking by-product hydrogen is  
low, and purification to high-purity hydrogen requires complicated technological process.  
The by-product hydrogen in the chlor-alkali industry comes from cathode gas produced with  
caustic soda and chlorine. Its principle and production process are similar to water electrolysis,  
and the purity of hydrogen obtained is high. In 2019, the output of caustic soda in China was  
nearly 35 MtA. Accordingly, the annual by-product hydrogen in China’s chlor-alkali industry  
was about 900 thousand t/a.  
The by-product hydrogen of propane dehydrogenation comes from the process of  
dehydrogenation of alkanes to olefins and hydrogen, and the purity of hydrogen obtained is  
relatively high. At present, the capacity of propane dehydrogenation projects already built and  
under construction in China is nearly 10 MtB. According to this calculation, the by-product  
hydrogen of propane dehydrogenation can reach 400 thousand t/a.  
2.1.1.4 Other Hydrogen Production Technologies  
In addition, hydrogen production technology also includes biomass hydrogen production,  
hydrogen production by water photolysis and so on.  
1. Hydrogen production from biomass  
Biomass hydrogen production is a form of biomass energy utilization. Since biomass itself is a  
zero-carbon energy source, hydrogen produced from biomass can also be defined as green  
hydrogen. The energy and material cycles of biomass hydrogen production is shown in Figure  
2.11. Combining biomass hydrogen production with CCUS technology can also achieve  
“negative emission”.  
A Source: IHS Markit.  
B Chen Hao, et al., Analysis on the Development Trend of Propane Dehydrogenation Process. Petroleum  
Refinery Engineering, 2020. 50(11): p. 9-13.  
031  
The Development and Outlook of Green Hydrogen  
Figure 2.11 Energy and Material Cycles of Hydrogen Production from Biomass  
Hydrogen production from biomass is mainly divided into thermochemical hydrogen  
production and microbial hydrogen production. The technical principle of thermochemical  
hydrogen production is close to that of fossil fuels hydrogen production, with wide sources of  
raw materials and easy realization of large-scale production. However, biomass has a complex  
composition, high oxygen and water content, its hydrogen production rate per unit mass is not  
as good as that of fossil fuels, the hydrogen concentration is low, and the pyrolysis process  
may cause other environmental pollution, etc.. The advantages of microbial hydrogen  
production are wide sources of raw materials, clean and renewable solar energy and mild  
reaction conditions. However, low hydrogen production efficiency and complicated process  
are the key problems that limit the large-scale industrial application of this method.  
2. Hydrogen production by photolysis of water  
Photocatalytic decomposition of water for hydrogen production can realize the direct  
conversion of solar energy to hydrogen energy. Since Fujishima and Honda first reported  
photocatalytic decomposition of water on TiO2 electrode in 1972A, hydrogen production by  
photolysis of water and semiconductor photocatalytic materials have attracted extensive  
attention and are still in the laboratory research stage.  
There are three main steps for hydrogen production by photolysis of water: first, the  
semiconductor is excited by light, and electrons transition from Valence band (VB) to  
Conduction band (CB), and holes are generated in VB, forming photo-generated electron-hole  
pairs, that is, two photo-generated carriers; The second is the migration of photo-generated  
carriers, and some photo-generated carriers are transported to the surface by the catalyst bulk  
phase; The third is surface reaction, that is, part of photo-generated carriers reaching the  
surface are captured by adsorbed water molecules, causing decomposition reaction of water  
A Fujishima A, Honda K. Electrochemical Photolysis of Water at a Semiconductor Electrode. Nature, 1972,  
238: 37-38.  
032  
2
Key Technologies for Green Hydrogen  
molecules, as shown in Figure 2.12. The selection of photocatalyst is very important in  
hydrogen production by water photolysis. Whether water can be successfully decomposed  
depends on the reduction-oxidation ability of photo-generated electrons and holes, which  
requires that the band gap of semiconductor is larger than the theoretical decomposition  
potential of water (1.23V), the bottom of conduction band is more negative than the reduction  
potential of water, and the top of valence band is more positive than the oxidation potential of  
water. At the same time, photo-generated carriers should be effectively separated to meet the  
kinetic requirements. At present, the quantum efficiency of most catalysts used for hydrogen  
production by water photolysis is low, which makes the overall conversion efficiency of solar  
energy to hydrogen energy low (generally around 1%)A. In addition, the reaction rate of water  
photolysis is relatively slow, far slower than the hydrogen production rate of electrolyzed water,  
and cannot meet the requirements of industrial production.  
Figure 2.12 Schematic Diagram of Water Photolysis  
2.1.2 Technology Comparison  
Using renewable energy to prepare green hydrogen has significant advantages of cleanness  
and low carbon. With the improvement of economy, the future development potential is huge.  
At the current electricity price level, the cost of hydrogen production from electrolyzed water is  
higher than that from fossil fuels. However, hydrogen production from electrolyzed water is  
clean and carbon-free, and the product purity is high, which is of great significance to realize  
carbon neutrality in the whole society. In the future, with the decline of the cost of wind power  
and PV power generation, as well as the technological progress, efficiency improvement and  
A Hiroshi Nishiyama, Taro Yamada, et al. Photocatalytic solar hydrogen production from water on a 100  
m2-scale. Nature, 2021, https://doi.org/10.1038/s41586-021-03907-3.  
033  
The Development and Outlook of Green Hydrogen  
cost reduction of electrolysis cells, green hydrogen will gradually become economical and  
become the mainstream hydrogen production mode.  
Compared with other ways of hydrogen production, the power of electrolytic hydrogen  
production is flexible and adjustable, which can become an important regulating resource in  
new power system and effectively promote the development and utilization of renewable  
energy. The power adjustment of electric hydrogen production technology is flexible,  
controllable, and interruptible, and it can be well-matched with the new energy power  
generation technology with strong randomness and volatility. Surplus electricity can be  
consumed during the trough load period of the power grid, stored for use by the demand side  
or converted back into electricity during the peak load period of the power grid, which can  
effectively stabilize the fluctuation brought by new energy power generation to the system and  
improve the new energy utilization efficiency. In the future power system dominated by new  
energy, it will become a valuable flexible regulation resource in the power grid.  
The carbon emission of hydrogen production from fossil fuels cannot be ignored, and it needs  
to be coordinated with CCUS technology in the future. At present, the global annual hydrogen  
production consumes are about 205 billion m3 of natural gas, accounting for 6% of the total  
natural gas consumption, and about 107 Mt of coal, accounting for 2% of the total coal  
consumption. The global hydrogen production industry emits 830 Mt of carbon dioxide.  
Compared with grey hydrogen, blue hydrogen can reduce 90% of carbon emissions in the  
process of hydrogen production, and at the same time, it can effectively utilize the existing grey  
hydrogen production infrastructure, but the cost increases by 30%-50%. For areas with low  
cost of fossil fuels such as natural gas and good geological conditions for carbon dioxide  
sequestration, before green hydrogen is economical and widely used, developing blue  
hydrogen is a transitional scheme to effectively utilize existing energy infrastructure.  
The production cost of industrial by-product hydrogen is low, but the scale is limited. Industrial  
by-product hydrogen is a by-product of production process, which exists in coking, chlor-alkali,  
propane dehydrogenation and light hydrocarbon cracking industries, with low cost and no  
extra carbon emission. With the accelerating process of carbon neutralization in the whole  
society, high carbon emission industries such as coal chemical industry and petrochemical  
industry will gradually shrink, and the corresponding by-products will gradually decrease.  
By-product hydrogen of chlor-alkali industry is relatively clean and of high purity, so it is an  
effective and low-carbon hydrogen production method to make full use of it.  
Other hydrogen production technologies are still difficult to be widely applied. Hydrogen  
production from biomass and water photolysis has the advantages of mild reaction conditions  
and low or even zero carbon emissions, but the process of hydrogen production from biomass  
is complex and the large-scale preparation technology is not yet mature. Hydrogen production  
by photolysis of water is still in the stage of laboratory research, facing the problems of low  
production efficiency and so on. At present, the main technical features and cost-effectiveness  
comparison of hydrogen production are shown in Table 2.3.  
034  
2
Key Technologies for Green Hydrogen  
Table 2.3 Technical Features and Cost-effectiveness Comparison of Main  
Hydrogen Production Technologies at Present  
Carbon  
Current cost  
(RMB/kg)  
emission  
(kg /kg,  
CO2/H2)  
Raw  
material  
Method  
Processed by  
Purity  
High  
Technical stage  
AEC and PEM  
are the practical  
stage and SOEC  
is the  
demonstration  
stage  
Hydrogen  
production  
through water dominant.  
At present, AEC is  
Water  
0
15-40  
7-15  
electrolysis  
Natural gas hydrogen  
production  
Natural  
gas, water  
Relatively  
low  
9-11  
Practical stage  
Hydrogen  
production  
from fossil  
fuels  
Partial oxidation of  
heavy oil  
Oil, water  
Low  
Low  
17-21  
20-25  
8-17  
7-10  
Practical stage  
Practical stage  
Coal gasification  
Coal, water  
Hydrogen  
production  
from  
chlor-alkali  
is higher  
and coking  
is lower  
Industrial  
by-product  
hydrogen  
Chlor-alkali, propane  
dehydrogenation,  
coking, etc.  
—
—
—
Practical stage  
Thermochemical  
hydrogen production,  
biological hydrogen  
production  
Hydrogen  
production  
from biomass  
Partial practical  
stage  
Biomass  
Water  
—
—
—
0
—
—
Water  
Photolysis  
Photocatalytic water  
decomposition  
Research stage  
2.1.3 R&D Direction  
1. High-efficiency and High-Power Alkaline Electrolysis Technology  
The R&D direction of alkaline electrolysis cell focuses on high power, high current density,  
further improvement of electrolysis efficiency and system integration technology. For the  
adaptation of the unstable generation of wind, solar and other renewable energy sources, it is  
necessary to strengthen the theoretical research on the dynamic characteristics of the  
electrode process under the condition of power fluctuation.  
The main research directions include: mass production technology of large-area electrode  
materials with high activity, low cost and high stability; New preparation technology of modified  
asbestos membrane or non-asbestos membrane with low impedance, high hydrophilicity, high  
stability and high corrosion resistance in strong alkali environment; Structural optimization  
design and integration technology of high-power alkaline electrolysis cell; Optimization design  
035  
The Development and Outlook of Green Hydrogen  
and integration technology of complete equipment for hydrogen production by electrolysis  
water with wide power fluctuation adaptability, optimization technology of electric-thermal-  
mass balance of hydrogen production system under wide power fluctuation condition.  
2. Low-cost Proton Exchange Membrane Electrolysis Technology  
The R&D direction of PEM electrolysis cell technology focus on the design and mass  
production of low-cost catalysts, proton exchange membranes and other key materials, reduce  
the equipment cost and improve the applicability and cost-effectiveness in specific scenarios  
such as distributed and fast adjustment.  
The main research directions include: the research on the preparation process of low noble  
metal catalyst, the design and manufacture of high activity, stable and long-life non-noble  
metal catalyst in strong acid environment; Design and preparation technology of proton  
exchange membrane with high conductivity, high strength and high stability, and study the  
preparation equipment of PEM suitable for continuous industrial production; Low-cost and  
large-scale membrane electrode coating and molding technology, and batch preparation  
technology of membrane electrodes, bipolar plates and other components, etc..  
3. Long-life High-Temperature Solid Oxide Electrolysis Technology  
The R&D direction of high-temperature solid oxide electrolyzer mainly includes prolonging the  
service life of electrolysis cell, strengthening system thermal management, modeling and  
optimal control of SOEC, etc., to improve the adaptability under large-scale fluctuation of  
power and the flexibility of conversion between electrolysis and power generation.  
The main research directions include: in theory, systematically study the surface chemistry and  
defect chemistry behavior of SOEC electrode, develop electrode materials with new structure  
and composition, and improve the stability and service life under high temperature and high  
humidity conditions; Optimize electrode/electrolyte interface, develop new configuration and  
new stack technology, realize long-term stable operation of SOEC under high current density,  
and improve fast response performance and robustness under dynamic working conditions;  
develop efficient heat exchangers, optimize system heat management, and effectively utilize  
waste heat to improve system energy exchange efficiency; Develop low-cost engineering  
materials suitable for SOEC system with high temperature resistance and good compatibility to  
improve the safety of the system; Make the new coupling mode of SOEC system with different  
upstream energy networks (electricity, heat, gas, etc.) and the connection with downstream  
high value-added chemicals preparation process, etc..  
At present, alkaline electrolysis cell technology is mostly used in electrolytic hydrogen  
production, with an electrolysis efficiency of about 70% and cost for hydrogen production  
system is RMB 3500−5000/kW. It is estimated that by 2030, the manufacturing technology of  
key materials such as high-efficiency electrocatalyst, PEM, membrane electrode, air  
compressor, hydrogen storage system, hydrogen circulation system and other key  
components will make a breakthrough, the efficiency of electrolytic hydrogen production will  
rise to about 80%, and the cost of hydrogen production system will drop to about RMB  
3000/kW. By 2050, the key technologies such as cheap and efficient electrocatalyst, long-life  
036  
2
Key Technologies for Green Hydrogen  
and high-stability high-temperature solid oxide stack have made breakthroughs, the  
high-temperature solid oxide electrolysis technology tends to be mature, the efficiency of  
electrolytic hydrogen production has increased to about 90%, and the cost of hydrogen  
production system has dropped to about RMB 2000/kW. By 2060, the hydrogen production  
technology will be further mature, and the cost of the hydrogen production system is expected  
to fall below RMB 2000/kW.  
2.1.4 Technical and Economic Trends  
Grey hydrogen needs to be combined with CCUS technology, changing grey hydrogen to blue  
hydrogen. The source carbon emissions from grey hydrogen run counter to the original  
intention of helping the whole society for carbon neutrality, and should not be blindly expanded.  
The CO2 emissions of hydrogen production from natural gas and coal are about 10 times and  
20 times that of hydrogen production, respectively. Considering the efficiency loss of hydrogen  
production process, the carbon emissions of the whole process generated by using grey  
hydrogen at the terminal are higher than those generated by directly using fossil fuels.  
Therefore, hydrogen production from fossil fuels is bound to be combined with CCUS  
technology, which will transform high-carbon grey hydrogen into low-carbon blue hydrogen. At  
present, the cost of blue hydrogen is about RMB 16-23/kg. With the progress of CCUS  
technology, it is expected that the cost of blue hydrogen will be slightly reduced to RMB  
15-21/kg by 2030.  
With the decline of the cost of generation by renewable energy, it is estimated that by around  
2030, hydrogen production by green electricity will gradually become the mainstream of  
hydrogen production. At present, when the cost of electricity is RMB 0.35-0.4/kWh, the cost of  
electrolytic hydrogen production is about RMB 21-25/kg, and the cost of electricity accounts  
for 70%-80% of the total cost. If it is matched with renewable energy to generate electricity, the  
utilization rate of hydrogen production equipment will decrease, and the cost of hydrogen  
production will be higher, which has less cost-effectiveness than industrial by-product  
hydrogen and blue hydrogen. It is estimated that by 2030, the LCOE of China’s PV and onshore  
wind power will be reduced to RMB 0.15/kWh and RMB 0.25/kWh respectively, and the  
average green hydrogen preparation cost will be reduced to about RMB 20/kg. In some areas  
with better resources, the utilization rate of hydrogen production equipment can reach about  
40%, and the green hydrogen cost can be as low as RMB 15-16/kg. Compared with blue  
hydrogen, it has more advantages on cost-effectiveness and gradually becomes the mainstream  
hydrogen production method. By 2050, new technologies such as high-temperature solid  
oxide electrolysis cell will make a breakthrough, the electrolysis efficiency will reach 90%, the  
electricity generation cost of renewable energy will be reduced to RMB 0.1-0.17/kWh, and the  
cost of electrolytic hydrogen production will be reduced to RMB 7-11/kg. Hydrogen production  
by electrolysis of water from renewable energy will become the most important way of  
hydrogen production. By 2060, with the further maturity of electrolytic hydrogen production  
technology and the further reduction of the cost of renewable energy generation, the cost of  
electric hydrogen production will be reduced to RMB 6-10/kg. The cost development trend of  
green hydrogen, blue hydrogen and grey hydrogen is shown in Figure 2.13.  
037  
The Development and Outlook of Green Hydrogen  
Figure 2.13 Comparison of Carbon Emission and Production Cost of Green  
Hydrogen, Blue Hydrogen and Gray Hydrogen  
Before the large-scale promotion of green hydrogen, industrial by-product hydrogen and blue  
hydrogen are expected to become the transition scheme to meet the demand for hydrogen.  
Industrial by-product hydrogen does not produce extra carbon emissions, which is low in cost  
and should be fully utilized. However, it is difficult to meet the demand of rapid development of  
hydrogen energy due to capacity constraints. Before 2030, low-carbon blue hydrogen is more  
cost-effective than green hydrogen. Based on the existing capacity of hydrogen production  
from fossil fuels, the popularization and application of CCUS technology should be accelerated,  
and grey hydrogen should be converted into blue hydrogen on the supply side. In the initial  
transitional stage of hydrogen industry development, make full use of existing resources to  
promote the construction of hydrogen industry chain cleanly and efficiently.  
2.2 Storage and Transportation Technology  
Hydrogen storage and transportation is the key link of hydrogen from production to application.  
The smooth operation of hydrogen industry chain in the future needs the cooperation of various  
technologies of hydrogen storage and transportation. The energy per unit mass of hydrogen is  
3-4 times that of fossil fuels, but the energy density per unit volume of hydrogen under normal  
temperature and pressure is less than one third of that of natural gas. Therefore, the key of  
hydrogen storage and transportation technology is to increase the energy density of hydrogen  
storage and transportation and reduce the cost as much as possible. At the same time,  
considering that hydrogen is a flammable and explosive gas, it is necessary to ensure the  
safety of hydrogen storage and transportation.  
2.2.1 Current Technical Status  
2.2.1.1 Hydrogen Storage Technology  
Hydrogen storage methods can be divided into three categories according to their existing  
state: gaseous hydrogen storage, liquid hydrogen storage and material-based hydrogen  
038  
2
Key Technologies for Green Hydrogen  
storage. Gaseous hydrogen storage and liquid hydrogen storage increase the density of  
hydrogen by means of high pressure and low temperature. And there are many ways to store  
hydrogen in materials, including material adsorption, metal hydride and organic liquid.  
1. Gaseous hydrogen storage  
High pressure gaseous hydrogen storage technology means that hydrogen is compressed by  
high pressure above the critical temperature, and gaseous hydrogen is stored in high-density  
form. High pressure gaseous hydrogen storage technology has the characteristics of low cost,  
low energy consumption and easy dehydrogenation, and is the most mature way of hydrogen  
storage at present. Under the condition of higher temperature and lower pressure, the  
properties of hydrogen conform to the ideal gas equation of state, and the density is  
proportional to the pressure. However, due to the fact that actual molecules always occupy a  
certain space and there is the interaction between molecules, with the increase of pressure,  
hydrogen gradually deviates from the properties of the ideal gas, and the relationship between  
density and pressure is no longer linear. The deviation from ideal gas can be expressed by  
compressibility factor Z:  
pV  
Z =  
nRT  
In which, p is the pressure, V is the volume, T is the temperature in Kelvin, n is the number of  
moles of gas, and R is the molar gas constant. The compressibility factor Z of hydrogen is  
always greater than 1 and increases with the increase of pressure, reaching 1.46 at 70MPa.  
Because of the existence of the compressibility factor, the benefits of increasing pressure on  
hydrogen storage density will be lower and lower. For example, doubling the pressure at  
70MPa can only increase the hydrogen storage capacity by another 40%-50%. And the high  
working pressure makes more strict requirements for the material and wall thickness of the  
hydrogen storage tank. It is considered that the working pressure of hydrogen storage tank at  
55-60MPa can achieve the optimal economic benefitsA. At present, the 35MPa hydrogen  
storage tank is a mature product, and the 70MPa high-pressure storage tank of Toyota is the  
one with the highest commercial working pressure, which is mainly used for FCV.  
High-pressure hydrogen is generally obtained by compressor. Hydrogen compressors  
including reciprocating compressors, membrane compressors, centrifugal compressors,  
rotary compressors, screw compressors, etc.. It sometimes needs multi-stage compression to  
meet the requirements of hydrogen storage pressure. Although the hydrogen compressor is  
similar to the natural gas compressor in principle, because of the smaller molecular weight of  
hydrogen, the compressibility factor is quite different from that of natural gas, which has a  
stricter requirement of system tightness and has different power systems. The structure of  
hydrogen compressors includes an inlet system and an outlet system. The inlet system  
consists of a gas-water separator, buffer, pressure-reducing valve and other components. The  
outlet system mainly consists of a dryer, filter, check valve, and other components.  
A SUN B G, ZHAN D S, LIU F S.Analysis of the cost-effectiveness of pressure for vehicular high-pressure  
gaseous hydrogen storage vessel[J]. International Journal of Hydrogen Energy, 2012, 37(17):  
13088-13091.  
039  
The Development and Outlook of Green Hydrogen  
High-pressure hydrogen is usually stored in high-pressure hydrogen storage tanks. Generally  
speaking, for hydrogen storage tanks of the same material, the mass hydrogen storage density  
decreases with the increase of pressure because the high working pressure requires a thicker  
wall. At present, commercialized high-pressure hydrogen storage tanks can be divided into  
four types: Type I, Type II, Type III and Type IV. Type I and II tanks are mainly made of metal,  
but the outer layer of Type II tank is wrapped with glass fiber composite material. Type III and  
IV tanks are mainly made of carbon fiber-reinforced composite material, Type III bottles are  
made of metal, Type IV bottles are made of plastic, and the outside is made of carbon fiber  
reinforced plastic. The commonly used materials of metal storage tanks such as Type I and  
Type II tanks are austenitic stainless steel, copper, aluminum, etc., which have the advantages  
of easy processing and low price. However, due to the high density of metal, the hydrogen  
storage density of the system is low. Metal storage tanks are only suitable for fixed hydrogen  
storage with small storage capacity, and 20MPa steel hydrogen tanks have been widely used  
in industry, but they cannot meet the requirements of vehicle-mounted systems. Type III tank,  
that is, metal-lined fiber-wound storage tank, is a high-pressure vessel composed of metal and  
nonmetal materials, which is often used as a large-capacity hydrogen storage tank. Its  
structure is a metal lining, its external winding a variety of fibers after curing to form a  
reinforced structure. As shown in Figure 2.14, the tank generally includes the lining, fiber  
winding layer and buffer layer, etc..  
Figure 2.14 Schematic Diagram of Fiber-wound Composite Storage Tank Structure  
In order to further reduce the self-weight of the container, fully composite light fiber wound  
storage tank, that is, IV tank, was developed by replacing the metal lining with the composite  
plastic lining. The composite plastic liner is generally made of high-density polyethylene, which  
has a wide temperature range and better impact toughness than the metal liner. Good air  
tightness can be ensured by adding sealant, surface fluorination, and sulfonation. The mass of  
full composite light fiber wound storage tank is only about 50% of that of steel tanks with the  
same storage capacity. It is highly competitive in vehicle-mounted hydrogen storage system  
and still in the R&D stage. The main research institutions and achievements are shown in  
Table 2.4. Only Japan and Norway have achieved commercial application.  
040  
2
Key Technologies for Green Hydrogen  
Table 2.4 Main Research Institutions and Achievements of Full  
Composite Light Fiber Wound Storage Tanks  
Country  
Company / Organization  
Quantum  
Working pressure (MPa)  
Status  
35-70  
70  
Development completed  
Development completed  
Completed by stages  
Commercialized  
The United States  
General Motors  
Impco  
69  
Norway  
Netherlands  
China  
Hexagon Composites  
DSM  
70  
—
Development completed  
Research stage  
Zhejiang University  
Air Products& Chemicals  
FAURECIA  
70  
—
Development completed  
In commercialization  
Research stage  
France  
Japan  
70  
Automobile Research Institute  
Toyota  
37-70  
70  
Commercialized  
Besides gas storage tanks, underground spaces such as salt caves, rock caves, depleted oil  
and gas reservoirs and water layers can be used to realize geological storage of hydrogen.  
Hydrogen storage under such geological conditions is expected to realize large-scale  
hydrogen storage, but the geological conditions are harsh, the stored hydrogen is easily  
polluted, and hydrogen leakage and reaction with microorganisms, liquids, rocks, etc.. will also  
cause hydrogen loss. Hydrogen storage tank is still the best choice for universal scenarios and  
small-scale hydrogen storage applications.  
2. Liquid hydrogen storage  
Liquid hydrogen storage technology liquefies hydrogen at high pressure and low temperature,  
and utilizes its characteristics of high volumetric energy density to realize high-efficiency  
hydrogen storage, and its transportation efficiency is also much higher than that of gaseous  
hydrogen. It is a common storage and transportation method of large-capacity hydrogen.  
However, the conditions of high pressure and low temperature not only have higher  
requirements on the material of hydrogen storage tanks, but also need to be matched with  
strict heat insulation scheme, cooling equipment and special temperature-raising valves in use.  
Therefore, the storage tank volume of low-temperature liquefied hydrogen storage is generally  
small, and the hydrogen storage density per unit mass of the system is about 5%−10%. Due to  
the lower temperature required by hydrogen liquefaction and higher energy consumption in the  
process, the energy consumption in the process of hydrogen liquefaction accounts for about  
25%−40% (10−16kWh/kg) of the liquefied hydrogen energy, which is much higher than the  
proportion of 10% of natural gas energy consumed by natural gas liquefaction, so the  
comprehensive operation cost of low-temperature liquid hydrogen storage is higher.  
At present, there are dozens of liquid hydrogen plants in the world with a total production  
capacity of about 480t/d, of which North America accounts for more than 60% of the world.  
There are 4 liquid hydrogen plants in Europe with a total capacity of 24 t/d; There are 16 liquid  
041  
The Development and Outlook of Green Hydrogen  
hydrogen plants in Asia, with a total capacity of 38.3 t/d, of which Japan’s capacity accounts  
for two thirds. Global industrial gas giants such as Air Liquid, Air Products, Linde and Praxair  
are all developing and applying large-scale hydrogen liquefaction plants. The largest  
hydrogen liquefaction plant in the United States was built by Praxair, with a capacity of 34 t/d  
and liquefaction power consumption of about 12.5-15kWh/kg. There are several large-scale  
hydrogen liquefaction plants operating in the Air Products, with a maximum capacity of 34 t/d  
and minimum power consumption of 10-12kWh/kg liquid hydrogen. At present, there are only a  
few liquid hydrogen plants serving the aerospace field in China, including Wenchang, Hainan,  
No.101 Institute in Beijing and Xichang Base, etc., with a total capacity of about 4 t/d, and no  
civilian liquid hydrogen in market.  
3. Material-based hydrogen storage  
Hydrogen storage technology based on material includes solid hydrogen storage, organic  
liquid hydrogen storage, liquid ammonia hydrogen storage and so on. Solid hydrogen storage  
stores hydrogen in solid materials through chemical reaction or physical adsorption, and its  
core is solid hydrogen storage materials, including metal alloys, carbonaceous materials,  
boron-nitrogen-based materials, metal-organic frameworks and so on. In principle, organic  
hydrogen storage, liquid ammonia hydrogen storage, methanol hydrogen storage and other  
technologies transform hydrogen into another easily stored substance through chemical  
reaction, and then release hydrogen through chemical reaction when hydrogen is needed.  
Metal hydrogen storage materials store hydrogen in the alloy by reacting with hydrogen to  
generate metal hydride. Under a certain temperature and pressure, this kind of material  
absorbs hydrogen to generate metal hydride by exothermic reaction, and under the condition  
of heating, it releases hydrogen by endothermic reaction, forming a cycle of absorbing and  
releasing hydrogen:  
  
M + H2  
MH  
2
  
Metal hydride hydrogen storage generally has a high hydrogen storage density per unit volume,  
but its heavy weight leads to a low hydrogen storage density per unit mass. For example, the  
hydrogen storage mass fraction of magnesium hydride and aluminum hydride is only 8% and  
10% respectively, and the hydrogen storage mass fraction of the system is only 4%-5%. At  
present, this kind of hydrogen storage materials has been preliminarily applied in some  
demonstration projects. At the same time, hydrogen storage by metal hydride often faces the  
binary paradox between hydrogen storage stability and hydrogen release energy consumption,  
that is, the more stable the formed metal hydride, the higher the energy consumption during  
hydrogen release.  
Carbon material-based hydrogen storage uses the adsorption of carbon materials such as  
activated carbon, carbon nanofibers, graphite nanofibers and carbon nanotubes to store  
hydrogen, which mainly belongs to the category of physical hydrogen storage. Due to the weak  
interaction between hydrogen and carbonaceous materials, expanding the specific surface  
area and improving the adsorption capacity of hydrogen on the surface of materials are the key  
factors to improve the hydrogen storage performance of materials. Carbonaceous hydrogen  
042  
2
Key Technologies for Green Hydrogen  
storage materials are still in the basic research stage, and the understanding of their hydrogen  
storage mechanism is not sufficient, and the chemical and physical changes in the process of  
hydrogen storage cannot be fully understood, so there is still a long way to go before practical  
application.  
Boron-nitrogen-based hydrogen storage generally has a higher theoretical hydrogen storage  
capacity, because boron and nitrogen are both light elements and can combine multiple  
hydrogen atoms. Ammonium borane (NH3BH3) is a typical representative of boron-nitrogen-  
based high-density solid hydrogen storage materials with high hydrogen storage mass fraction  
and hydrogen storage density per unit volume. However, ammonia borane alone as a  
hydrogen storage material has higher hydrogen release temperature, lower hydrogen release  
efficiency and is prone to produce toxic impurity gases such as borazine.  
Hydrogen storage technologies based on solid-state are currently in the R&D stage, and there  
are still many technical problems to be solved before industrial application.  
Hydrogen storage technology based on organic liquid has high hydrogen storage density, and  
organic liquid can be recycled through hydrogenation and dehydrogenation. Taking  
toluene-methylcyclohexane system as an example, when hydrogen is stored, toluene is  
hydrogenated to generate methylcyclohexane, and when hydrogen is released,  
methylcyclohexane is dehydrogenated to generate hydrogen and toluene:  
Other commonly used materials, such as benzene-cyclohexane system, naphthalene-decalin  
system, etc., are suitable for melting and boiling point range of these organic compounds,  
which are in liquid state at normal temperature and pressure, can be stored and transported  
like gasoline, and can be recycled for many times. However, organic liquid hydrogen storage  
must be equipped with corresponding hydrogenation and dehydrogenation devices, which is  
costly. Dehydrogenation reaction is often accompanied by side reactions, which leads to the  
decrease of hydrogen purity. At the same time, the dehydrogenation catalyst is easy to  
deactivate.  
Hydrogen storage technology based on liquid ammonia combines hydrogen with nitrogen to  
generate ammonia, and liquid ammonia is used as the carrier of hydrogen energy for storage,  
transportation or utilization. The boiling point of ammonia at normal pressure is about −33℃,  
which is 220℃ higher than that of liquid hydrogen, so it is convenient for storage and  
transportation. The process of hydrogen synthesis ammonia is mainly Haber process, that is,  
nitrogen and hydrogen are combined to synthesize ammonia under the action of catalyst at  
high temperature and high pressure. Ammonia can be decomposed at normal pressure and  
high temperature of 800-900 ℃ to obtain nitrogen and hydrogen, which is a strong  
endothermic reaction, and about 20% of hydrogen needs to be used as fuel to provide the  
energy needed for the reaction. The total energy efficiency of hydrogen-ammonia-hydrogen  
process is only about 50%-55%, and the obtained hydrogen needs further purification.  
Therefore, it is of a certain value to use this technology for storage and transportation when the  
043  
The Development and Outlook of Green Hydrogen  
end user can directly use ammonia. If the end user needs high purity hydrogen, the overall  
storage and transmission system works at low efficiency and high cost.  
Generally speaking, the hydrogen storage technology based on organic liquids, liquid  
ammonia, and methanol can obtain higher hydrogen storage density, and can also store  
hydrogen under moderate conditions. However, the hydrogen release process generally needs  
to absorb additional energy, and the obtained hydrogen needs to be purified. Other hydrogen  
storage technologies based on chemical compounds such as complex hydrides and inorganic  
substances are still in the research stage, and the hydrogen storage and release performance  
need to be further improved. How to improve the total energy efficiency of hydrogen storage  
and release cycles and how to improve the selectivity of hydrogen desorption reactions is the  
main problem to be solved by hydrogen storage technologies.  
2.2.1.2 Hydrogen Transportation Technology  
Hydrogen transportation includes hydrogen transportation through the pipelines, land route,  
and waterway in the form of compressed gas or liquid.  
1. Hydrogen transportation through pipelines  
Hydrogen transportation through pipelines may be carried out by blending hydrogen into  
natural gas pipeline networks or building a dedicated hydrogen pipeline network.  
At present, there are nearly 3 million kilometers of natural gas transmission pipelines around  
the world, and blending hydrogen into mature natural gas pipeline networks for transportation  
can provide great impetus for the development of hydrogen energy. To meet the requirements  
of pipeline safety and characteristics of end-use appliances, the blending ratio of hydrogen is  
generally in the range of 5%−15%A.  
Dedicated hydrogen pipeline is an important way to transport hydrogen over long distances  
with low operating cost, low energy consumption and large volume. A dedicated hydrogen  
pipeline network is divided into the transportation of gaseous and liquid hydrogen. Hydrogen is  
of small molecules, high risk of escape, and demanding requirements for material in terms of  
high-pressure hydrogen, the construction cost of building a dedicated hydrogen pipeline  
network is high. A liquid hydrogen pipeline network needs to run under low-temperature  
conditions, therefore, it has higher requirements for construction and operation technology and  
of higher cost.  
By 2019, the total length of a dedicated hydrogen pipeline network in the world is 4543km,  
including 2608km in the United States and 1598km in Europe, as shown in Figure 2.15. The  
operating pressure of the hydrogen pipeline network in the United States is generally not more  
than 7MPa, and that of hydrogen pipelines in Europe is between 2MPa and 10MPa. Seamless  
steel pipelines are mostly used in such networks. There is a high concentration of companies  
that build and operate dedicated hydrogen pipeline networks, such as Air Liquid, Air Products,  
A Li Jingfa, et al., Research Progress of Hydrogen-blended Natural Gas Pipeline Transmission Network.  
Natural Gas Industry, 2021. 41(04): p. 137-152.  
044  
2
Key Technologies for Green Hydrogen  
Linde, and Praxair, and the total market share of such four companies reaches nearly 90%, as  
shown in Figure 2.16. The hydrogen pipelines in China mainly include the Baling-Changling  
hydrogen pipeline and the Jiyuan-Luoyang hydrogen pipeline, with a total length of 42km and  
25km, respectively. They mainly provide hydrogen raw materials for hydrogenation reactors in  
the petrochemical industry. Compared with developed countries, China’s hydrogen  
transportation technology based on pipelines is still in its infancy, with limited experience in  
construction and operation.  
Figure 2.15 Global Status of Dedicated Hydrogen Pipeline Networks  
Figure 2.16 Constructors and Operators of Dedicated Hydrogen Pipeline Networks Around the World  
At present, the hydrogen pipeline network in the Gulf of Mexico of the United States is the  
largest network in the world, with a total length of about 1000km. There are 23 hydrogen  
production plants along the hydrogen pipeline network, with a total production capacity of over  
1.2 Mt/a, and 50 hydrogen facilities, as shown in Figure 2.17.  
045  
The Development and Outlook of Green Hydrogen  
Figure 2.17 Scientific Diagram of Hydrogen Pipeline Network in the Gulf of Mexico, United States  
In addition to conventional steel materials, new materials such as fiber reinforced polymer (FRP)  
and polymer-layered silicate (PLS) are also used for hydrogen pipeline research. FRPs are less  
liable to cause hydrogen embrittlement, of strong resistance to corrosion, and a life of up to 50  
years, and they can save 20% to 30% of the installation cost compared with steel pipes.  
However, the FRP pipeline has a high hydrogen leakage rate and low hydrogen transportation  
pressureA.  
The design life of a hydrogen pipeline network is generally 30−40 years. The hydrogen  
transportation cost mainly includes depreciation and amortization of pipeline construction cost,  
direct operation and maintenance costs (material cost, maintenance cost, loss in hydrogen  
transportation, employee compensation, etc.), management cost, and hydrogen compression  
cost. Throughout the lifecycle of the pipeline, the total fixed cost accounts for about 80% of the  
total cost, and the variable cost accounts for 20%. According to some practical cases and  
research cases in China, the composition of hydrogen transportation cost through pipelines  
under different design transportation capacities is calculated as shown in Table 2.5. Generally  
speaking, under the same load rate, the unit cost of hydrogen transportation gets lower when  
the transmission capacity of pipelines gets larger.  
The annual transportation capacity of hydrogen transportation through pipelines depends on  
the design capacity and operating pressure and is insensitive to the transportation distance.  
For pipelines with a hydrogen transportation capacity of 100,000 t/a, assuming that the  
transportation distance is S (km), the total annual transportation cost C (RMB) for operation  
under different load rate X is as follows:  
C = (308 000 + 24 640)S +10×107 × 0.42S X +13897S  
The unit transportation cost (c) [RMB/(t·km)] is:  
(308 000 + 24 640)S +10×107 × 0.42S X +13897S  
c =  
10×104 S X  
A Smith B, Eberle C, Frame B, et al., Mays J. FRP Hydrogen Pipelines, FY 2006 Annual Progress Report, 2,  
2006.  
046  
2
Key Technologies for Green Hydrogen  
Table 2.5 Composition of Hydrogen Transportation Cost through Pipelines  
Design transportation  
capacity (10,000 t/a)  
Cost Item  
Fixed cost  
Composition  
Amount Unit of measurement  
Pipeline depreciationa  
308,000  
RMB/(year·km)  
RMB/(year·km)  
RMB/kg  
Maintenance and management fee b 24,640  
10  
50  
Hydrogen compression fee c  
Hydrogen transportation loss d  
Pipeline depreciationa  
0.42  
Variable cost  
Fixed cost  
13,897  
733,300  
RMB/(year·km)  
RMB/(year·km)  
RMB/(year·km)  
RMB/kg  
Maintenance and management feeb 108,600  
Hydrogen compression feec  
Hydrogen transportation lossd  
0.42  
Variable cost  
5431  
RMB/(year·km)  
Note: a Including pipeline construction cost, part of the maintenance cost, and interest on loans for a  
30-year operation period;  
b
Including part of the maintenance cost, personnel cost, management cost, and work safety  
cost of the pipelines;  
c
Including the costs of fuel and energy and auxiliary materials;  
d
It refers to the cost of hydrogen leakage and loss during transportation.  
As shown in Figure 2.18, the ton-kilometer cost of pipelines is significantly affected by the  
transportation capacity utilization rate. The unit transportation cost increases significantly when  
the transportation capacity utilization rate decreases; the transportation cost changes slightly  
when the utilization rate increases to above 40%. When the hydrogen transportation distance  
exceeds 200km, the system utilization rate is higher than 40%, and the hydrogen transportation  
cost is lower than RMB10/(t·km).  
Figure 2.18 Relationship between Transportation Cost and  
Transportation Distance of Hydrogen Pipelines  
047  
The Development and Outlook of Green Hydrogen  
At present, the dedicated hydrogen pipelines have a transportation capacity of 100,000m3,  
smaller than that of natural gas pipelines. Institutions such as Hydrogen Council and Entso-g  
have carried out studies on the dedicated hydrogen pipeline network with a transportation  
capacity of 10 billion m3, and it is expected that the investment cost will be about 1.5 times that  
,
B
of the gas pipelines under the same pressure and pipeline diameterA  
.
2. Hydrogen transportation by land transport  
Hydrogen transportation by land transport includes highway and railway transportation, mainly  
delivering the high-pressure gaseous hydrogen and liquid hydrogen. Tube trailer is mainly  
used to transmit high-pressure gaseous hydrogen, and hydrogen in domestic hydrogen  
refueling stations is mainly delivered by tube trailers. High-pressure tube trailers, which are  
commonly used in China, are generally equipped with 8 high-pressure gas storage pipes with  
a diameter of 0.6m, a length of 11m, nominal working pressure of 0.2−30MPa, and a working  
temperature of −40−60℃. The mass of full-load hydrogen is only about 200−500kg, and the  
overall utilization rate of the system is only 75% to 85% because the returning pressure cannot  
be too low.  
Most of the domestic hydrogen refueling stations use tube trailers to transmit the hydrogen  
externally supplied, which is suitable for users with a short transportation distance, low  
transportation volume, and tons of daily hydrogen consumption. When the hydrogen is  
transmitted to the hydrogen refueling stations by tube trailers, it enters the compressor for  
compression, and then it is delivered to the HP, MP, and LP storage tanks for grading storage.  
When the automobile needs to be hydrogenated, the hydrogen dispensers will inject the  
hydrogen from the tube trailer, the LP, MP, and HP hydrogen storage tanks in sequence.  
The transportation cost of tube trailers mainly includes the fixed cost (depreciation cost,  
personnel salary, etc.) and variable cost (including electricity fee for hydrogen compression,  
fuel cost, etc.). The details are shown in Table 2.6.  
Table 2.6 Composition of Transportation Cost by Tube Trailer  
Cost Item  
Composition  
Depreciation expense  
Labor cost  
Amount  
100,000  
300,000  
10,000  
0.2  
Unit of measurement  
RMB/year  
RMB/year  
RMB/year  
RMB/km  
Fixed costs  
Vehicle insurance fee  
Maintenance cost  
Fuel cost  
1.5  
RMB/km  
Variable cost  
Road toll  
0.7  
RMB/km  
Electricity fee for hydrogen compression  
0.6  
RMB/kg  
A Hydrogen Council, Hydrogen Insights 2021, 2021.  
B Entso-g, European Hydrogen Backbone, 2020.7.  
048  
2
Key Technologies for Green Hydrogen  
In the case of a large annual total transportation volume, the number of hydrogen trailers can  
be adjusted to cope with the change of transportation volume and ensure the full-load  
operation of vehicles. It can be seen from the above that the annual fixed cost of tube trailers is  
RMB 410,000, and the variable cost depends on the transportation distance. The unit  
transportation cost of hydrogen varying with the change of transportation distance can be  
calculated. As shown in Figure 2.19, when the transportation distance is 200−500km, the  
hydrogen transportation cost is RMB25−20/(ton·km).  
Figure 2.19 Relationship between Transportation Cost and  
Transportation Distance of Tube Trailers  
Tanker trucks are mainly used to transport cryogenic liquid hydrogen. The liquid hydrogen  
density is 70.85kg/m3, 800 times that of gaseous hydrogen, and the full-load volume of a single  
liquid hydrogen tank truck is about 65m3, which can transmit 4000kg of hydrogen, and the  
transportation efficiency is high. Japan and the United States have taken liquid hydrogen tank  
trucks as an important means of hydrogen transportation for hydrogen refueling stations. However,  
the transportation of liquid hydrogen requires a low-temperature environment, and during  
long-distance transportation, the problems of liquid hydrogen gasification and pressure rise need to  
be solved. There are no cases of liquid hydrogen transportation for civil use in China.  
The transportation cost composition of liquid hydrogen tank trucks is similar to that of tube  
trailers but it has an additional cost of hydrogen liquefaction and the loss of boiling of liquid  
hydrogen during transportation. The cost of liquid hydrogen tank trucks is shown in Table 2.7.  
Table 2.7 Composition of Transportation Cost by Liquid Hydrogen Tank Trucks  
Cost Item  
Composition  
Depreciation expense  
Labor cost  
Amount  
45,000  
300,000  
10,000  
0.2  
Unit of measurement  
RMB/year  
RMB/year  
RMB/year  
RMB/km  
Fixed costs  
Vehicle insurance fee  
Maintenance cost  
Fuel cost  
Variable cost  
1.5  
RMB/km  
Road toll  
0.7  
RMB/km  
049  
The Development and Outlook of Green Hydrogen  
continued  
Cost Item  
Composition  
Amount  
0.5  
Unit of measurement  
Liquefaction loss rate  
%
Variable cost  
Electricity fee for hydrogen liquefaction  
Loss rate during transportation  
6.6  
RMB/kg  
%/h  
0.01  
The cost-effectiveness of liquid hydrogen storage and transportation is closely related to the  
storage amount. The power consumption of liquefying hydrogen with the same calorific value is  
several times to ten times higher than that of compressing hydrogen. In addition, it has high  
requirements for the material selection and technical level of the liquid hydrogen storage tank,  
therefore, the initial investment cost is high. The costs (equipment investment and power  
consumption cost) of the liquefaction process account for 70% to 80% of the hydrogen  
transportation cost. Due to the strong scale effect of liquefaction equipment, the hydrogen  
transportation cost by liquid hydrogen tank trucks decreases significantly with the increase of  
transportation scale; meanwhile, with the increase of transportation distance, the total cost  
changes little, which is characterized by a significant decrease in the transportation cost of unit  
distance. The change in transportation cost of the unit distance of liquid hydrogen tank trucks  
is shown in Figure 2.20. When the hydrogen transportation distance is more than 500km, the  
hydrogen transportation cost is about RMB 12/(t·km).  
Figure 2.20 Relationship between Transportation Cost and Transportation  
Distance by Liquid Hydrogen Tank Trucks  
Railway hydrogen transportation is mainly based on liquid hydrogen tank trucks.  
Long-distance transportation of liquid hydrogen by cryogenic rail tank trucks is characterized  
by a large transportation capacity and relatively low cost. The storage devices of tank trucks  
are usually the cylindrical dewar tanks that are horizontally placed with a storage capacity for  
liquid hydrogen up to 100m3, and some special expanded railway tank trucks have a capacity  
up to 120−200m3, which can transmit 7−14 tons of hydrogen. There is currently only a very  
small amount of railway routes for hydrogen transportation abroadA.  
A Wang Yeqin, et al., Analysis on the Construction Planning Of “Mother-Son Station” for Hydrogen Production  
and Hydrogenation. Chemical Industry and Engineering Progress, 2020. 39(S2): p. 121-127.  
050  
2
Key Technologies for Green Hydrogen  
Metal tank trucks can be used to transmit solid hydrogen storage materials, and the problems  
of high pressure for compressing hydrogen and the possible gasification of liquid hydrogen at  
low temperature can be avoided to some extent. The low-pressure and high-density solid  
storage tank is only used as the on-board hydrogen transportation container, and the heating  
medium and devices are placed at the hydrogen charging and using site, which can realize  
the rapid charging of hydrogen and the high-density and high-safety transportation in a  
synchronous manner, improve the hydrogen transportation capacity and safety of a single tank  
truck, and thus reduce the hydrogen transportation cost. At present, the transportation of solid  
hydrogen storage materials is in the state of research or small-scale experiments and has not  
been commercially applied.  
3. Hydrogen transportation by waterway transport  
At present, hydrogen transportation by waterway is mainly applied for long-distance  
transportation by the sea where liquid hydrogen (including liquid hydrogen, hydrogen-bearing  
organic liquid, and liquid ammonia) is transmitted in large quantities by special liquid hydrogen  
barges. Sea transportation is suitable for hydrogen transportation with a long distance and  
large capacity. Calculated by the transportation capacity of 170,000m3 for an LNG ship, the  
single hydrogen transportation volume can reach 12,000 tons. Hydrogen-carrying organic  
liquids and liquid ammonia cannot be directly used as final hydrogen products, and hydrogen  
regeneration is required through chemical methods after arrival at the destination. Therefore, it  
is necessary to build necessary infrastructures such as loading and unloading facilities,  
storage tanks, liquefaction and regasification plants at appropriate loading and unloading  
docks for hydrogen transportation by the sea, which is more economical when hydrogen  
production plants and hydrogen users are close to the docks.  
CHIYODA, a Japanese company, applied the organic liquid hydrogen storage technology  
based on a toluene-methylcyclohexane system to hydrogen transportation by the ocean in the  
“SPERA Hydrogen” project, as shown in Figure 2.21. With toluene-methylcyclohexane as the  
carrier of hydrogen, the company transmitted the hydrogen from Brunei to Kawasaki, Japan  
through sea barges, with a one-way distance of about 5000km. The annual transportation  
capacity of the project is 210 tons of hydrogen.  
Figure 2.21 Schematic Diagram of Hydrogen Transportation by Marine  
System Using Methylcyclohexane  
051  
The Development and Outlook of Green Hydrogen  
4. Replacing hydrogen transportation with electricity transportation  
In addition to transmitting the practical hydrogen molecules, delivering green electricity, the  
source of green hydrogen, can also realize large-scale and long-distance transportation of  
hydrogen. UHV transmission technology can realize the power transmission of several  
thousand kilometers and tens of millions of kilowatts, and the interconnection of transnational  
and transcontinental power grids. Flexible transmission can improve the flexibility of system  
operation, meet the requirements of friendly grid connection of clean energy such as  
photovoltaic power and wind power, and support the flexible configuration of clean energy.  
High-quality and low-cost clean electricity can be transmitted from areas rich in renewable  
resources such as wind and light to the hydrogen demand center through transportation  
technology for local hydrogen production, so as to achieve the effect of green hydrogen  
transportation by the transmission of green electricity.  
Technologies such as 330kV AC, 500kV AC, ±500kV DC, ±800kV DC, and ±1100kV DC can be  
selected for replacing hydrogen transportation with power transmission based on different  
capacities and distances. Power transmission technology has been constructed and operated  
for many years compared with other hydrogen transportation technologies. In the 21st century,  
China has vigorously promoted research and engineering construction for power transmission  
technology, completed and put into operation twelve 1000kV UHV AC transmission projects  
such as Southeast Shanxi — Nanyang — Jingmen Project, thirteen ±800kV UHV DC  
transmission projects such as Xiangjiaba — Shanghai Project, and the Zhundong — southern  
Anhui ±1100kV UHVDC Transmission Line Project. In the past, advanced power transmission  
has replaced a part of the electricity-coal transmission, realizing the optimal allocation of coal  
resources nationwide and playing a comprehensive benefit in economic, ecological, and  
regional coordinated development. In the future, the method of replacing hydrogen  
transportation with power transmission will achieve the large-scale and long-distance  
transportation of hydrogen and it is of great significance to the optimal allocation of renewable  
energy and green hydrogen resources nationwide. The schematic diagram of coal and power  
transmission and hydrogen transportation and power transmission is shown in Figure 2.22.  
Figure 2.22 Schematic Diagram of “Replacing Hydrogen  
Transportation with Power Transmission” (1)  
052  
2
Key Technologies for Green Hydrogen  
Figure 2.22 Schematic Diagram of “Replacing Hydrogen  
Transportation with Power Transmission” (2)  
2.2.2 Technology Comparison  
2.2.2.1 Comparison of Hydrogen Storage Technologies  
Hydrogen storage technology is the basis of hydrogen transportation technology, and the form  
of hydrogen storage determines the form and technical route of hydrogen transportation.  
Hydrogen storage technologies pursue higher hydrogen storage density, higher hydrogen  
mass ratio, more moderate hydrogen storage environment, and lower energy consumption.  
Each hydrogen storage technology has its own advantages and disadvantages, as shown in  
Table 2.8.  
Table 2.8 Comparison of Characteristics of Main Hydrogen Storage Technologies  
Storage  
Mass fraction  
of hydrogen  
storage (%)  
density of  
hydrogen  
(kg/m3)  
Requirement for  
environment  
Hydrogen  
release condition  
Method  
Technical stage  
Practical stage  
High pressure  
gaseous hydrogen  
storage technology  
Normal temperature,  
high pressure  
Pressure  
reduction  
10−40  
60−80  
1−6  
5−7  
1−5  
5−8  
(10−70MPa)  
Cryogenic liquid  
hydrogen storage  
technology  
Ultra-low temperature  
Temperature rise Practical stage  
In the  
(below −240℃)  
Solid hydrogen  
storage technology  
Normal temperature  
and pressure  
Heating  
demonstration  
stage  
100−150  
45−100  
Organic/liquid  
ammonia hydrogen  
storage technology  
High temperature  
catalytic  
decomposition  
In the  
demonstration  
stage  
Normal temperature  
and pressure  
053  
The Development and Outlook of Green Hydrogen  
High pressure gaseous hydrogen storage technology is the most mature and widely used  
hydrogen storage technology with low cost, small energy consumption, and easiness of  
dehydrogenation. For the fixed storage of hydrogen, such as the storage of hydrogen refueling  
stations and hydrogen inlet and outlet terminals, high pressure gaseous hydrogen storage  
technology is still the best choice at present. Liquid hydrogen storage technology takes lots of  
energy, but it has high efficiency in hydrogen storage, which can adapt to different modes of  
transportation, such as highway, railway, and sea transportation, and has certain development  
potential. Solid-state hydrogen storage technology is featured by high hydrogen storage  
density, therefore, it has unique application potential in scenarios with space requirements.  
Organic liquid hydrogen storage technology and liquid ammonia hydrogen storage technology  
are featured by a high mass fraction and moderate hydrogen storage conditions, for example,  
they can solve the problems of hydrogen release efficiency and reaction selectivity, therefore,  
they will have great advantages in long-distance hydrogen transportation.  
2.2.2.2 Comparison of Hydrogen Transportation Technologies  
1. Technical features  
Hydrogen transportation technology evolves based on the development of hydrogen storage  
technology. Different hydrogen transportation methods are selected according to different  
hydrogen storage technologies and forms, and the cost-effectiveness of hydrogen  
transportation technology depends on that of hydrogen storage technology to some extent.  
For hydrogen stored in a gaseous state, tube trailers and pipelines are commonly used for  
hydrogen transportation. Gaseous hydrogen transportation has the advantage of low energy  
consumption. Liquid hydrogen and hydrogen-bearing organic liquid are generally transmitted  
by special tankers and barges, which can transport a large amount of hydrogen in a single time,  
but the hydrogen preparation and release process cost much energy. Solid hydrogen storage  
materials can be transmitted by metal tanker trucks, but it is still in the small-scale test stage. At  
present, high pressure gaseous hydrogen storage and low-temperature liquefied hydrogen  
storage technologies are well-developed, and short-distance gaseous hydrogen transportation  
in tube trailers and liquid hydrogen transportation in tanker trucks have been commercially  
applied. The long-distance large-scale hydrogen transportation by sea depends on the  
supporting infrastructure near the port such as hydrogen conversion plant and gasification  
plant. Chemical hydrogen storage technologies, such as hydrogen storage in organic liquids,  
have more advantages than liquid hydrogen in shipping, and with the maturity of the  
technology of hydrogen storage in organic liquids, it is expected to be commercially applied.  
The comparison of technical features of main hydrogen transportation technologies is shown in  
Table 2.9.  
2. Application scenario analysis  
Various hydrogen transportation technologies have their own characteristics and are suitable  
for different scenarios. For small-scale and medium and short-distance hydrogen  
transportation within cities or between regions, the construction of hydrogen transportation  
pipelines or power transmission lines requires a higher initial investment, and hydrogen  
transportation by tube trailers and liquid hydrogen tank trucks are more flexible. For large-scale  
054  
2
Key Technologies for Green Hydrogen  
Table 2.9 Comparison of Characteristics of Main Hydrogen Transportation Technologies  
Energy  
efficiency of  
hydrogen  
storage and  
transportation  
(%)  
Energy  
Energy  
Energy  
Hydrogen  
storage  
method  
Hydrogen  
transportation  
method  
Transportati consumption consumption consumption  
on  
for  
for  
for hydrogen  
release  
(kWh/kg)  
equipment preparation pressurization  
(kWh/kg)  
(kWh/kg)  
Hydrogen  
transportation  
through pipelines  
Pipe  
<1  
1.5  
—
—
95  
90  
Gaseous  
hydrogen  
storage  
Hydrogen  
transportation by Tube trailer  
land transport  
2
1
1
Hydrogen  
transportation by  
land/waterway  
transport  
Liquid  
hydrogen  
tank  
Liquid  
hydrogen  
storage  
10−16  
—
75  
85  
truck/barge  
Solid  
hydrogen  
storage  
Hydrogen  
transportation by  
land transport  
Metal tank  
truck  
—
—
2
2
11  
technology  
Organic/liqui  
d ammonia  
hydrogen  
storage  
Hydrogen  
transportation by Liquid tank  
land/waterway  
transport  
10  
85  
truck/barge  
technology  
and long-distance hydrogen transportation, such as hydrogen transportation from large-scale  
green hydrogen production bases to urban consumers and others, hydrogen transportation  
through pipelines and replacing hydrogen transportation with power transmission has distinct  
advantages. For coastal areas, it is also an economical and feasible way to allocate hydrogen  
resources by producing hydrogen at overseas clean energy bases and transmitting the  
hydrogen across the ocean through liquid hydrogen, hydrogen-carrying organic liquids, liquid  
ammonia, and other methods. The application scenarios of different hydrogen transportation  
technologies are shown in Figure 2.23.  
For small-scale and short-distance transportation, the high initial investment makes the  
dedicated hydrogen transportation pipelines have  
a higher unit cost and lower  
cost-effectiveness. Moreover, the market demand for short-distance and small-scale  
transportation is uncertain. In terms of adaptability to market risks, the single transportation  
volume of tube trailers and tank trucks is moderate, and when the market demand fluctuates,  
the number of tube trailers and tank trucks can be adjusted to ensure the full-load operation of  
vehicles. The change of annual total transportation volume has little influence on unit  
transportation cost, therefore, this transportation method is highly adaptable to market demand  
fluctuation. Although the unit transportation cost for hydrogen transportation through pipelines  
is low under full load operation condition, such advantage is guaranteed by its huge  
transportation capacity, and it is significantly affected by the transportation volume. Once the  
market demand decreases, the design transportation capacity can not be fully utilized, and the  
cost of hydrogen transportation through pipelines will increase significantly.  
055  
The Development and Outlook of Green Hydrogen  
Figure 2.23 Applicable Scenarios of Different Hydrogen Transportation Technologies  
For hydrogen transportation at close range, the transportation cost of liquid hydrogen tank  
trucks is higher than that of tube trailers. It is mainly because that it takes large energy  
consumption in the liquid hydrogen preparation process, and the production cost accounts for  
a large proportion of the transportation cost of the liquid hydrogen tank truck. When the  
transportation distance increases, the unit transportation cost of the liquid hydrogen tank truck  
decreases significantly. Tube trailers have a certain cost advantage in short-distance  
transportation within 300km, while liquid hydrogen tank trucks take advantage in  
medium-distance transportation over 300km. The comparison in the cost-effectiveness of tube  
trailers, liquid hydrogen tank trucks, and hydrogen transportation through pipelines on  
small-scale and short-distance transportation cases is shown in Figure 2.24.  
Figure 2.24 Comparison in the Cost-effectiveness of Three Transportation  
Methods on Small-scale And Short-distance Transportation Cases  
056  
2
Key Technologies for Green Hydrogen  
For small-scale and medium-distance transportation, liquid hydrogen, hydrogen-bearing  
organic liquid (taking toluene-methylcyclohexane system as an example), liquid ammonia, and  
other liquid hydrogen-containing compounds can be transmitted by dedicated tank trucks,  
which is a feasible scheme in this scenario. The similarity of these three technologies is the  
large energy consumption in hydrogen production or release. The energy loss in the liquid  
hydrogen production (i.e., the ratio of energy consumption to the transmitted hydrogen) is  
about 30%, and that in the hydrogen release process is negligible. Japan has applied  
hydrogen transportation based on a toluene-methylcyclohexane system, and the energy loss in  
the hydrogen production and release is about 28%. For liquid ammonia, the energy  
consumption in ammonia synthesis and ammonia decomposition to produce hydrogen is high,  
with the energy loss ranging from 45% to 50%. The greater the energy consumption during  
hydrogen production and release, the greater the impact on the cost of short-distance  
transportation.  
One of the major advantages of liquid hydrogen or liquid compound hydrogen storage  
technologies is that the hydrogen is of high density in storage and transportation and the  
transportation efficiency is high. The density of liquid hydrogen is 71kg/m3, the density of  
hydrogen in methyl cyclohexane and liquid ammonia is 48kg/m3 and 120kg/m3, respectively,  
which are higher than that in the pressure of 70MPa (about 40kg/m3). The characteristics  
comparison of hydrogen stored and transmitted in liquid hydrogen, methylcyclohexane, and  
liquid ammonia is shown in Table 2.10.  
Table 2.10 Comparison of Hydrogen Storage and Transportation in Liquid Hydrogen,  
Methylcyclohexane, and Liquid Ammonia  
Hydrogen  
transportation method  
Energy loss during hydrogen  
production and release (%)  
Hydrogen storage and transportation  
density (kg/m3)  
Liquid hydrogen  
Methylcyclohexane  
Liquid ammonia  
30  
71  
48  
About 28  
45−50  
120  
From the treatment after hydrogen release, a purification process is needed for hydrogen  
transportation in liquid ammonia and methylcyclohexane, which increases additional costs;  
however, it is not necessary for hydrogen transportation in liquid hydrogen.  
Based on the above analysis, three hydrogen transportation technologies, i.e. liquid  
hydrogen, methylcyclohexane, and liquid ammonia, are compared, and the results are  
shown in Figure 2.25. Liquid hydrogen tank trailer remains the most economical method in  
small-scale and medium-distance scenarios. For hydrogen transportation by  
methylcyclohexane technology, the storage and transportation density of hydrogen is lower  
than that by liquid hydrogen technology, and a purification process is needed after hydrogen  
release, so the cost is higher than that in liquid hydrogen technology. For liquid ammonia, the  
energy loss during hydrogen production and release is large and purification is required after  
release, so the cost is also higher than that by liquid hydrogen technology. However, for  
hydrogen-carrying organic liquids such as liquid ammonia and methylcyclohexane, if the  
existing transportation equipment can be used, the initial investment can be cut to a certain  
057  
The Development and Outlook of Green Hydrogen  
extent and the transportation cost can be reduced.  
Figure 2.25 Comparison in the Cost-effectiveness of Three Transportation Methods on  
Small-scale And Medium-distance Transportation Cases  
For large-scale and long-distance transportation, pipelines or replacing hydrogen transportation  
with power transmission may be selected for hydrogen transportation. At present, hydrogen  
transportation through pipelines is not widely applied, and there is no application example of  
pipelines with a transportation capacity of tens of billions of cubic meters. With reference to the  
West-East Gas Pipeline Project in China, the investment cost per unit length of natural gas  
pipelines with a design annual capacity of 12 billion cubic meters is about RMB 13.5 million/km,  
and that of hydrogen transportation pipelines of the same scale is about 1.5 times that of  
natural gas pipelines, that is, about RMB 20 million/km. When the annual transportation  
capacity reaches the designed transportation capacity, the unit cost of transmitting hydrogen  
and natural gas by 2000km pipelines is about RMB 0.35/m3 (RMB 4/kg) and RMB 0.23/m3, as  
shown in Table 2.11.  
Table 2.11 Transportation Cost per Unit Volume of Natural Gas and Hydrogen  
Transportation technology  
Hydrogen transportation  
0.35  
Natural gas  
0.23  
Transportation cost per unit volume (RMB/m3)  
UHV DC transmission technology is mature for long-distance and large-capacity power  
transmission. The economical power transmission distance of ±800kV DC project is about  
1500−2500km, and the transmission capacity is 8−10million kW. The transmission distance of  
±1100kV DC project can reach 3000−4500km, and the transmission capacity can reach 10−12  
million kW. The investment cost of UHVDC projects mainly includes convertor stations and lines  
at both ends. In combination with the actual project investment and operation parameters of  
UHVDC projects in China, including the Xiangjiaba-Shanghai ±800kV HVDC Transmission  
Demonstration Project, Xilinguole League- Taizhou ±800kV HV DC Transmission Project,  
Zhundong - Southern Anhui ±1100kV HV DC Transmission Project, the investment in a single  
convertor station with convertors at a voltage level of ±800kV and ±1100kV will be about RMB  
4.36 billion and RMB 7.67 billion respectively, and the investment per unit length in overhead  
line project will respectively be about RMB 4.1 million/km and RMB 7.02 million/km, as shown in  
Table 2.12.  
058  
2
Key Technologies for Green Hydrogen  
Table 2.12 Investment Cost of UHV DC Transmission Projects  
Capacity  
Total Investment of a single convertor station  
(RMB 100 million)  
Investment per kilometer  
Voltage class  
(MW)  
(RMB10,000 /km)  
±800kV  
8000  
43.6  
76.7  
410  
702  
±1100kV  
12,000  
±The annual transmission capacity of ±800kV UHV DC transmission project is about 48 billion -  
60 billion kWh, which can produce 850,000 tons to 10.5 Mt of hydrogen at the receiving end,  
equivalent to the hydrogen transportation capacity of pipelines with a capacity of 10 billion  
cubic meters, and the power transmission cost is about RMB 0.06/kWh.  
Compared with the transmission cost of different energy resources such as power, hydrogen,  
and natural gas, the energy unit shall be uniform. The unit of energy measurement shall be kWh  
in reports. The energy contained in hydrogen and natural gas per cubic meter under standard  
conditions is about 3.6kWh and 10kWh respectively, and the energy of hydrogen is only about  
one-third of that of the natural gas in the same volume. The unit cost of power, hydrogen, and  
natural gas transmission at a distance of 2000km is shown in Table 2.13.  
Table 2.13 Unit Cost of Power, Hydrogen, and Natural Gas Transmission  
Transmission technology  
Power  
0.06  
Hydrogen  
0.096  
Natural gas  
0.023  
Unit transmission cost (RMB/kWh)  
From the perspective of the unit transmission cost, the method of replacing hydrogen  
transportation with power transmission is economical in large-scale and long-distance onshore  
hydrogen transportation scenarios.  
2.2.3 R&D Direction  
1. Hydrogen Liquefaction Technology  
Hydrogen liquefaction technology is a key technical link to realize the application of liquid  
hydrogen. Brayton ammonia circulation technology is usually used by small and medium-sized  
hydrogen liquefaction equipment, and Claude hydrogen circulation technology is usually used  
by large-scale hydrogen liquefaction equipment to achieve cooling liquefaction at  
low-temperature zone through isentropic expansion of hydrogen turboexpander. Ammonia  
turboexpander and hydrogen turboexpander are the core equipment in two processes  
respectively, and the latter is technically difficult.  
The main research focuses on the design of high-efficiency hydrogen turboexpander,  
optimization of unit parameters and dynamic simulation technology, design and manufacturing  
process of large, high-efficiency, low - temperature hydrogen heat exchanger, and the sealing  
and thermal insulation technology of low-temperature turboexpander system.  
059  
The Development and Outlook of Green Hydrogen  
2. Hydrogen Storage Tank Technology  
Hydrogen storage tank technology is the key to efficient storage and transportation of  
hydrogen in different forms. In order to achieve higher hydrogen storage density, it is  
necessary to increase the pressure of gaseous hydrogen storage, which has a higher  
requirement for the pressure resistance and sealing performance of storage tanks under high  
pressure. In order to achieve higher hydrogen transportation efficiency, it is necessary to  
increase the proportion of hydrogen mass, which requires that the dead-weight of the  
hydrogen storage container be reduced as much as possible provided that the hydrogen  
storage demand and safety are met. At present, the full composite light fiber wound storage  
tank has an excellent performance in all aspects, and the mass is only half of that of the  
cylinder under equivalent storage volume, which is the key development project in different  
countries. The thermal insulation performance of liquid hydrogen storage tanks needs to be  
improved to reduce the energy consumption in the thermal insulation process.  
The main research focuses on the carbon fiber wound high-pressure hydrogen cylinder  
manufacturing technology, the key of technology is to avoid hydrogen permeation from the  
plastic liner under high pressure and connection and sealing between the plastic liner and the  
metal interface, develop the insulation technologies such as high vacuum insulation, vacuum  
multi-layer insulation and large-area cooling screen, propose the basic strategy of hydrogen  
container combustion and explosion protection, study the safety design method of hydrogen  
storage device, and form a comprehensive safety and health diagnosis method of hydrogen  
storage device.  
3. Hydrogen transportation technology based on pipelines  
The R&D directions of hydrogen transportation technology based on pipelines mainly include  
reducing the corrosion of pure hydrogen or blending hydrogen into natural gas to the pipes,  
improving transportation safety, and developing pressure regulating equipment related to the  
dedicated hydrogen pipeline network.  
The main research focuses on developing new materials for hydrogen transportations, such as  
fiber-reinforced polymer and polymer-layered silicate, research on the leakage and diffusion  
mechanism of hydrogen pipelines, and research on the compatibility of pipes with pure  
hydrogen and natural gas mixed with hydrogen transportation; R&D of multi-stage pressure  
reduction and pressure regulation technology and equipment for the dedicated hydrogen  
pipeline network; R&D of hydrogen-blended natural gas pipeline and equipment, safety  
accident characteristics and evolution rules of the dedicated hydrogen pipeline network and  
the hydrogen-blended natural gas pipeline network, and emergency repair technology  
research; the research on pressurization technology at the end of the dedicated hydrogen  
pipeline network.  
4. Hydrogen Storage Technology Based on Solid Materials  
The R&D directions of hydrogen storage technology based on solid materials focus on  
improving the mass fraction of hydrogen storage, reducing the energy consumption during  
hydrogen release, the mass production of materials, and construction of hydrogen storage  
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system with solid hydrogen storage materials as the core.  
The main research focuses on studying the thermodynamics and dynamics of hydrogen  
absorption/desorption of hydrogen storage materials, designing and preparing hydrogen  
storage materials with high hydrogen storage mass fraction, controlling the hydrogen  
absorption/desorption speed of hydrogen storage materials with high mass fraction, studying  
the cycle performance attenuation mechanism of hydrogen storage materials, developing  
long-life hydrogen storage materials, and the study on type, content analysis and suppression  
method of impurities in hydrogen released by solid hydrogen storage materials.  
2.2.4 Technical and Economic Trends  
1. Hydrogen storage technology  
In terms of hydrogen storage technology, large-scale fixed hydrogen storage is expected to be  
in the form of high-pressure gaseous hydrogen storage with a storage pressure of 15−50MPa,  
and the current construction cost of hydrogen storage equipment is about RMB 1000 per  
kilogram of hydrogen. The storage tanks are mainly metal storage tanks and metal-lined fiber  
wound storage tanks. By 2030, the carbon fiber wound high-pressure hydrogen cylinder  
manufacturing technology is expected to be further mature, and the cost of hydrogen storage  
equipment is expected to decrease to RMB 500−800/kg hydrogen. By 2050 and 2060, it is  
expected to further decrease to about RMB 300/kg hydrogen and RMB 250/kg hydrogen.  
For small-scale storage technologies such as hydrogen storage for vehicles, the 35MPa and  
70MPa full composite light fiber wound storage tanks are mainly used at present. At present,  
the cost of a 35MPa fully composite light fiber wound storage tank is about RMB 3500 per  
kilogram of hydrogen, and that of a 70MPa full composite light fiber wound storage tank is RMB  
4500 per kilogram of hydrogen, but it has not been applied on a large scale. It is expected that  
by 2030, the 70MPa full composite light fiber wound storage tank technology will be mature  
and applied at a large scale, with the cost reduced to RMB 3500 per kilogram of hydrogen. By  
2050, the cost of high-pressure storage tanks will be further reduced, and breakthroughs will  
be made in the hydrogen storage technology based on solid materials and commercial  
application will be preliminarily realized. The cost of hydrogen storage equipment is expected  
to reach RMB 2000 per kilogram of hydrogen. By 2060, with the further maturation of hydrogen  
storage technology, the cost of hydrogen storage equipment is expected to further decrease to  
RMB 1500 per kilogram of hydrogen.  
Low-temperature liquid hydrogen storage or solid hydrogen storage materials are expected to  
remain the best choice for places with high space requirements, such as aerospace.  
2. Hydrogen transportation technology  
Different hydrogen transportation technologies are applicable to different scenarios, and  
appropriate technologies should be selected according to specific situations.  
In large-scale and long-distance onshore hydrogen transportation, the combination of  
replacing hydrogen transportation with power transmission and hydrogen transportation  
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The Development and Outlook of Green Hydrogen  
through pipelines will be used. It is expected that by 2030, the dedicated hydrogen pipeline  
network manufacturing technology and the pressure reduction and regulation technology will  
be mature, and the construction cost of large-scale hydrogen transportation pipelines  
(considering the annual transportation capacity of 12 billion m3) is expected to decrease to  
RMB 13.5 million/km, equivalent to the current cost of natural gas pipelines. The transportation  
loss (including gas loss and energy consumption) per 1000km of hydrogen transportation  
pipelines will be controlled at about 1%, and the unit hydrogen transportation cost will be  
controlled at RMB 2.7/kg. By 2050, new hydrogen transportation pipelines made of  
fiber-reinforced polymer composites and others are expected to be put into commercial use,  
the transportation loss per 1000km of hydrogen transportation pipelines will be controlled at  
0.3%−0.5%, and the unit hydrogen transportation cost will be controlled at about RMB 2/kg. By  
2060, with the further maturity of hydrogen transportation pipeline technology, the  
transportation loss per 1000km of hydrogen transportation pipelines is expected to further  
decrease to 0.1%−0.2%, reaching the current level of natural gas pipelines, and the unit  
hydrogen transportation cost will be below RMB 2/kg.  
In small-scale, medium- and short-distance onshore hydrogen transportation, tube trailers and  
tank trailers are mainly used. For example, for uncertain transportation demand with a distance  
of 300−1000km and an average transportation volume of fewer than 10 tons/day, the liquid  
hydrogen tank truck will be used, and the unit hydrogen transportation cost is RMB 5−10/kg  
based on the distance. For short-distance onshore hydrogen transportation, such as  
short-distance hydrogen delivery within a city or between regions, tube trailers will be used,  
and the unit hydrogen transportation cost is RMB 3−6 /kg.  
Intercontinental transportation of hydrogen will be realized by the transportation of liquid  
hydrogen, liquid ammonia, or hydrogen compounds by the sea. Liquid hydrogen  
transportation technology is mature, but it has high energy consumption during hydrogen  
liquefaction and it is easy to volatile during liquid hydrogen transportation. The liquid ammonia  
transportation technology is featured by mature ammonia storage and transportation facilities,  
which can be used to reduce the loss during transportation, and the high energy consumption  
during the hydrogen regeneration process. Hydrogen-carrying organic liquids, including  
methylcyclohexane, can make full use of the storage and transportation facilities in the existing  
petrochemical industry, and the key is whether such transportation method can achieve an  
efficient and selective hydrogenation/dehydrogenation process. It is expected that the cost of  
liquid hydrogen (or liquid ammonia, hydrogen-carrying organic liquid) transportation by the  
sea will be about RMB 14 per kilogram of hydrogen by 2050.  
2.3 Hydrogen Utilization Technology  
Hydrogen energy can be easily converted into heat, electricity, and other forms of energy.  
Meanwhile, hydrogen is also an important industrial raw material that can be applied in various  
scenarios. In some end-use areas where direct electrification is difficult, hydrogen is the key to  
achieving low carbon emissions. For example, it can be used in the field of transportation as  
the fuel for fuel cell vehicles to provide high-quality heat for industrial fields, or it can be applied  
in the distributed power generation or co-generation of thermal power projects as chemical raw  
materials; therefore it has great application potential.  
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2.3.1 Current Technical Status  
Hydrogen is widely used in energy, chemical industry, aerospace, electronic industry, food  
processing and other fields. At present, the hydrogen consumption in the world reaches 115 Mt  
per year, most of which comes from the chemical industry. The annual hydrogen consumption  
in three major industries, namely refining, ammonia synthesis and methanol synthesis,  
accounts for 70% of the world’s total, while the remaining 30% mainly comes from the use of  
raw materials in the fields of food, medicine and semiconductors, and few energy fields, except  
for aerospaceA . According to the data from China Hydrogen Alliance, China’s annual  
hydrogen consumption in 2019 was about 33 Mt, mainly in the ammonia synthesis, methanol  
synthesis, petrochemical and coal chemical industries, as shown in Figure 2.26. Compared  
with the world average level, more hydrogen is consumed in ammonia synthesis and methanol  
synthesis in China. According to the analysis of development requirements under carbon  
neutrality, hydrogen has great application potential in energy, transportation, metallurgy and  
other industries in the future.  
Figure 2.26 Current Hydrogen Consumption of Each Industry in China  
2.3.1.1 Chemical Industry  
1. Petroleum refining  
In the process of petroleum refining and chemical production, hydrogen is required as a  
feedstock for some process steps, mainly for removing impurities (such as sulfur) from crude  
oil and upgrading heavy oil, and to a lesser extent for preparing oil sands and biofuels.  
Hydrorefining and hydrocracking are the main hydrogen consumption processes in refineries.  
Hydrorefining is used to remove impurities from crude oil, especially sulfur, nitrogen, oxygen,  
etc. The current petroleum desulfurization process can remove 70% sulfur from crude oil.  
Hydrocracking is a process in which heavy oil is cracked by hydrogenation at high temperature  
and in the presence of catalysts, and converted into light fuel such as gasoline, kerosene and  
diesel oil. The main hydrogen units and corresponding hydrogen consumption of the refinery  
are shown in Table 2.14.  
A Source: IEA, The Future of Hydrogen, 2019.  
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The Development and Outlook of Green Hydrogen  
Table 2.14 Main Hydrogen Units and Hydrogen Consumption of the Refinery  
Hydrogen consumption  
(m3/t)  
Name of plant  
Names of raw materials  
Straight-run naphtha  
FCC naphtha  
Kerosene  
3
56  
8
Hydrogenation  
unit  
Low sulfur diesel (S content≤0.02%)  
Low sulfur diesel (S content≤0.05%)  
High sulfur diesel (S content≤0.2%)  
High sulfur diesel (S content≤0.5%)  
FCC diesel  
8
12  
25  
29  
83  
143  
Desulfurizer  
Atmospheric residue  
Desulfurized diesel (aromatic hydrocarbon content≤20%)  
Desulfurized diesel (aromatic hydrocarbon content≤10%)  
21  
48  
Dearomatization  
unit  
Vacuum wax oil  
171−214  
171−429  
Hydrocracking  
Atmospheric residue  
In 2018, the hydrogen consumption in petroleum refining in the world was about 38 Mt per year,  
accounting for one-third of the world’s total hydrogen demand. AAbout one-third of the  
hydrogen demand of the refinery can be met by other hydrogen by-products from other  
processes of the refinery. The other two-thirds of hydrogen is produced by the refinery’s  
dedicated facilities (most of which adopt hydrogen production process by methane steam  
reforming reactions) or outsourced.  
With the clean energy transition of the transportation industry, the demand for fuel oil will be  
greatly reduced, and petroleum oil will gradually revert from energy to feedstock. In the future,  
the demand for hydrogen in the entire petroleum refining industry will continue to decrease.  
2. Ammonia synthesis  
Ammonia is an important basic chemical feedstock mainly used for the production of  
chemical fertilizers, which accounts for about 70% of ammonia consumption and is called  
“ammonia for chemical fertilizer production”. At the same time, ammonia is also used for the  
production of dyes, explosives, synthetic fibers, synthetic resins, etc., which accounts for  
about 30% of ammonia consumption and is called “ammonia for industrial use”. As the  
population grows and human demand for food increases, the demand for ammonia  
synthesis will increase further.  
Ammonia is mainly synthesized by the Haber process, i.e., nitrogen and hydrogen are directly  
combined in the presence of catalysts at high temperature and high pressure to generate  
ammonia, which is an important basic inorganic chemical process, and the reaction formula is  
as follows:  
A Source: IEA, The Future of Hydrogen, 2019.  
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N2 + 3H2 = 2NH3  
The raw materials and processes for ammonia synthesis mainly depend on those for hydrogen  
production. At present, hydrogen is generally produced by coal gasification and natural gas  
steam reforming, corresponding to ammonia synthesis with coal (coal-to-ammonia process)  
and ammonia synthesis with natural gas (gas-to-ammonia process). The price levels of natural  
gas and coal in different regions are the main determinants of the selection of raw materials  
and process routes. Where technically feasible, hydrogen production from renewable energy  
can completely replace hydrogen production from fossil energy in the ammonia synthesis  
industry. In the future, with the decrease of the equipment cost in clean energy power  
generation and hydrogen production by water electrolysis, the proportion of hydrogen  
production from renewable energy in the ammonia synthesis industry is expected to continue  
to increase and reduce the carbon emission level in the industry.  
3. Methanol synthesis  
Methanol is an important feedstock for the C1 chemical industry and also a kind of high-quality  
liquid fuel. Compared with other alcohols, methanol serving as a feedstock is the most  
consumed and is widely used in the preparation of formaldehyde, MTBE, acetic acid, and  
olefins. China is the world’s largest producer of methanol, with output reaching 55.76 Mt in  
2018. Consumption of methanol in (Methanol to Olefins) MTO process is increasing.  
As a direct feedstock for methanol production, hydrogen is combined with carbon monoxide  
and carbon dioxide to generate methanol. Similar to ammonia synthesis, the methanol  
production process also includes a hydrogen production process using both coal and natural  
gas feedstocks, and the specific process path is selected mainly based on the feedstock cost.  
For methanol production, most countries in the world mainly adopt natural gas while China  
mainly adopts coal due to the constraints of energy resource endowment.  
Box 2.2  
Combining Carbon Capture with Power to raw  
Material Technology to Recycle Waste Materials  
—— Liquid Sunshine Demonstration Project  
In January 2020, the “1000-ton liquid solar fuel synthesis demonstration device”  
developed by Dalian Institute of Chemical Physics, Chinese Academy of Sciences,  
constructed and operated by Lanzhou New Area Petrochemical Industry Investment  
Group Co., Ltd. and designed by Hualu Engineering & Technology Co., Ltd. was  
successfully put into trial operation.  
The project consists of three basic units: solar photovoltaic power generation, hydrogen  
production by water electrolysis, and methanol synthesis with carbon dioxide and  
hydrogen. The catalytic technology for methanol production with carbon dioxide and  
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The Development and Outlook of Green Hydrogen  
hydrogen with high selectivity and stability is adopted, a photovoltaic power station with  
a total power of 10MW and two 1000 m3/hour water-electrolytic hydrogen making  
equipment are built, and the technical route is as shown in the following figure. The liquid  
solar fuel project is a typical case of combining carbon capture with the technology of  
power to fuel and raw materials. Renewable energy is used to convert the captured CO2  
into methanol, thus turning waste into wealth.  
Box 2.2 Figure Schematic Diagram of Liquid Sunshine Demonstration Project  
It is a new way to produce methanol by reducing carbon dioxide with hydrogen produced from  
renewable energy through water electrolysis. The methanol production process using the  
hydrogen produced from renewable energy is clean and zero-carbon and also can fix and  
utilize carbon dioxide emitted from other ways, so this process is expected to become an  
important way for producing methanol in the future. At present, several demonstration projects  
have been completed in Europe and China. The reaction process of reducing carbon dioxide  
with hydrogen to produce methanol requires high temperature (about 270℃) and high  
pressure (8MPa). With Cu-Zn-based metal oxide as a catalyst, carbon dioxide and hydrogen  
react to produce methanol and water, delivering a certain amount of heat (87kJ/mol). The  
chemical reaction equation is as follows:  
4. Methane synthesis  
Methane (CH4), mainly from gas-field exploitation and oil-gas-field exploitation, is the simplest  
organic matter and the main component of natural gas. Methane can be synthesized artificially  
by reducing carbon dioxide with hydrogen through the Sabatier reaction. With nickel,  
ruthenium and other metals as catalysts, carbon dioxide and hydrogen react to produce  
methane and water at a certain temperature (about 200℃) and pressure (2MPa), delivering a  
lot of heat (165kJ/mol). The reaction selectivity can reach over 90%. The chemical reaction  
equations are as follows:  
CO2 + 4H2 = CH4 + 2H2O  
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Key Technologies for Green Hydrogen  
The main reason that the hydrogen-to-methane process has not yet been used commercially  
on a large scale is that the vast majority of current hydrogen comes from fossil fuels, and it  
would be less efficient and less economical to use hydrogen to produce fossil fuels such as  
methane. At present, only a few demonstration projects have been completed in Germany,  
Spain and other European countries, mainly for exploring the use of Power-to-Gas (P2G)  
technology to improve the utilization of renewable energy generation and reduce wind and PV  
curtailment. In the future, with the large-scale development and cost reduction of renewable  
energy generation, there will be a greater potential for the synthesis of methane with hydrogen  
produced from renewable energy through water electrolysis and captured carbon dioxide as  
feedstocks. On one hand, it can improve the accommodating capacity of the energy system for  
renewable energy such as wind energy and solar energy fluctuating greatly. On the other hand,  
methane is easier to store, transport and use in terminals than hydrogen, and can be produced  
by directly using existing natural gas infrastructure, thus reducing investment in new facilities.  
The process of producing organic matters such as methane or methanol with hydrogen  
produced from renewable energy is essentially the use of clean power to regenerate the  
carbon dioxide generated after burning fossil fuels into usable fuels or feedstocks. This  
process, together with the original fossil energy utilization system, can form a carbon cycle  
system with zero carbon emissions. Carbon, absorbing and releasing energy through valence  
changes, is always a carrier of energy during this cycle, and electric power is the key to driving  
such reduction reactions. The cycle is shown in Figure 2.27.  
Figure 2.27 Schematic Diagram of Carbon Cycle  
In the metallurgy, chemical industry, industrial heating, and other fields where it is difficult to  
realize electricity replacement directly, the above carbon cycle system can indirectly realize  
electricity replacement and achieve zero carbon emission in the whole process of energy  
utilization without changing the end-use energy/raw materials. The carbon emission may be  
reduced by 2.8t per ton of methane produced from hydrogen produced from renewable  
energy compared to that produced directly from natural gas.  
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The Development and Outlook of Green Hydrogen  
The application of renewable energy-to-hydrogen in the chemical industry profoundly reflects  
the scientific connotation of the “One Conversion” concept of the GEI. New chemical industries  
such as methane synthesis and methanol synthesis based on renewable energy-to-hydrogen  
essentially take electricity as the driving force to realize the manual conversion of carbon,  
hydrogen, oxygen and other elements into different forms. Clean and renewable power allows  
non-renewable organic fuels and raw materials to be manually converted and recycled.  
2.3.1.2 Energy Field  
In the energy field, hydrogen is mainly applied to power generation, heating and cogeneration.  
However, hydrogen is less used in the energy field due to the high cost of hydrogen production.  
In terms of power generation, both hydrogen fuel cells and hydrogen fueled gas turbines are  
optional technical routes with their own advantages and disadvantages. Hydrogen energy  
generation will play an important role in the new power system mainly using renewable energy.  
Under the maximum output of renewable energy, the accommodating capacity of the system  
may be improved by the power-to-hydrogen process. When the system is in short supply of  
power, the power demand may be met by hydrogen energy generation. The power-hydrogen-  
power conversion process provides a large-scale and long-term energy storage for the power  
system, as shown in Figure 2.28.  
Figure 2.28 Schematic Diagram of Power-Hydrogen-Power Conversion Process  
Hydrogen has great potential for heating application in industrial and building fields. In the  
industrial field, cement, glass, paper making and textile industries need a lot of thermal energy,  
while the thermal energy demand in the building field includes space heating, hot water  
production, cooking, etc. Currently, thermal energy is mostly provided by fossil energy.  
Hydrogen energy heating technology offers options for carbon emission reduction in these  
fields, but it also often needs to compete with other clean energy heating technologies such as  
power heating and solar energy heating.  
1. Power generation by hydrogen fueled gas turbines  
The gas turbine is a rotating impeller-type heat engine that drives the impeller to rotate at a  
high speed with continuous flowing gas as the working medium, converting the energy of the  
fuel into mechanical energy. House service gas turbines are heavy-duty gas turbines in which  
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Key Technologies for Green Hydrogen  
the gas medium works externally through the Brayton cycle. The simple cycle process consists  
of four processes: power consumption compression, heat absorption for temperature rise,  
doing work through expansion, and heat release for enthalpy drop. The power mechanical  
structure of the gas turbine is shown in Figure 2.29. The compressor draws air from the outside  
atmosphere and pressurizes the air step by step through the axial-flow compressor, and the air  
temperature increases accordingly. Compressed air is pressed into the combustion chamber  
and mixed with the injected fuel for combustion to generate high-temperature and  
high-pressure gas, which then enters the turbine to do work through expansion, so as to drive  
the turbine to drive the compressor and the externally loaded rotor to rotate together at high  
speed, thus partially converting the chemical energy of gas or liquid fuel into mechanical work  
and outputting electric work. With low cost, good peak-load performance and low water  
consumption, the power station equipped with heavy-duty gas turbines can participate in deep  
peak regulation to ensure efficient and stable power systems.  
The gas turbines using hydrogen as the combustion gas can achieve zero greenhouse gas  
emissions, but the physical properties and combustion characteristics of hydrogen differ  
greatly from those of natural gas. The flame propagation speed of hydrogen is eight times that  
of natural gas, the specific heat capacity is seven times that of natural gas, and the diffusion  
coefficient in air is about three times that of natural gas, so gas turbines need to be modified to  
adapt to the changes in fuel characteristics. The technical difficulties of rich and pure hydrogen  
fueled gas turbines include three aspects: one is to solve the problems of tempering and flame  
oscillation to increase the safety and operability of turbines; second is to solve the automatic  
ignition of rich and pure hydrogen fueled gas turbines at high temperature and high pressure;  
third is to minimize NOx emissions through the design of combustion system.  
Figure 2.29 Operating Principle and Mechanical Structure of Gas Turbine  
Due to the fast combustion rate and high flame temperature of hydrogen fueled gas turbines,  
the thermal NOxA emission in the combustion chamber is nearly twice as high as that of natural  
gas combustion, which easily causes environmental pollution and equipment damage. In order  
to reduce the generation of NOx , it is necessary to reduce the flame temperature and shorten  
the flame residence time. There are two main technical routes. The wet low NOx (WLN)  
combustion method generally suppresses NOx emissions by spraying water to the  
high-temperature part of the flame, but with the evaporation of water, the power generation  
A Refers to nitrogen oxides generated by oxidation of nitrogen in the air at high temperatures during  
combustion.  
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The Development and Outlook of Green Hydrogen  
efficiency will decrease, and the untreated water will lead to the corrosion of turbine blades.  
The dry low NOx (DLN) combustion method has high power generation efficiency, which  
realizes combustion stability and short flame residence time through fractional combustion and  
premixed combustion methods, thus reducing NOx emissions. But some problems such as  
suppressing flame backflow still need to be solved.  
Companies such as Mitsubishi Hitachi Power Systems (MHPS), General Electric Company  
(GE), and SIEMENS have been committed to the research and application of rich and pure  
hydrogen fueled gas turbine for a long time, and have made some progress, with the hydrogen  
content in hydrogen combustion gas constantly increasing. As of 2018, MHPS has 29  
hydrogen-fueled gas turbines in service, which have operated for more than 3.57 million hours.  
The test results made by MHPS in 2018 show that the premixed burner can achieve stable  
combustion of 30% hydrogen and natural gas mixture, and the carbon dioxide emission per  
unit generation can be reduced by 10%A. GE has invested heavily in technology development  
for rich and pure hydrogen fueled gas turbines, and has developed two types of burners to  
solve the problems of hydrogen tempering and ignition, including single-nozzle silent burners  
for B- and E-class gas turbines and multi-nozzle silent burners for E- and F-class gas turbines,  
of which laboratory tests have been completed for B- and E-class gas turbines totally fueled by  
hydrogen energy. In 2019, Siemens also tested its pure hydrogen fueled gas turbinesB.  
2. Hydrogen fuel cell  
Fuel Cell (FC) is a generating set that directly converts the chemical energy of fuel into electric  
power through electrochemical reactions. Theoretically, any substance (namely fuels) capable  
of releasing chemical energy through a redox reaction, such as hydrogen (H2), methane (CH4),  
methanol (CH3OH), ammonia (NH3), or even solid carbon, can form a fuel cell with appropriate  
oxidants (typically oxygen O2). However, limited by the current engineering technology level,  
methane, methanol and other carbon fuel cells are prone to carbon deposition at the cathode,  
resulting in a rapid decline of activity. Limited by reaction kinetics, corrosion to electrodes,  
nitrogen oxide pollution, and other problems, ammonia fuel cells have not been popularized yet.  
The hydrogen fuel cell is the most widely used fuel cell technology at present because of its  
simple reaction system and clean product (H2O).  
Hydrogen fuel cell power generation is the inverse reaction of hydrogen production through  
water electrolysis, where the basic operating principle is that hydrogen (H2) is oxidized at the  
cathode end of a cell to produce hydrogen ions (H+) migrated to the anode through the  
electrolyte, as well as electrons (e-) migrated to the anode through an external circuit, and  
oxygen (O2) is reduced at the anode to react with hydrogen ions and electrons to form water  
(H2O). In this process, electrons flow through the external circuit to form a loop and generate a  
current. The operating principle of the hydrogen fuel cell is shown in Figure 2.30.  
A Li Haibo, et al., Analysis of the Application Prospect of Hydrogen-Fueled Gas Turbine Power Generation.  
Power Equipment Management, August 2020, 94-96.  
B Siemens. Power-to-X:The crucial businesson the way to a carbon-free world. 2020.  
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Key Technologies for Green Hydrogen  
Figure 2.30 Operating Principle of Hydrogen Fuel Cell  
There are many technical routes for fuel cells, which can be divided into five types by different  
electrolytes. Alkaline Fuel Cell (AFC) is the most mature fuel cell technology with potassium  
hydroxide as the electrolyte and was originally used in military, aerospace and other special  
fields. Proton Exchange Membrane Fuel Cell (PEMFC) is usually used in automobiles,  
submarines, portable power supplies and other fields because of the significant reduction in  
size by using the proton exchange membrane as the electrolyte, but it is costly. Phosphoric  
Acid Fuel Cell (PAFC), with strong phosphoric acid as the electrolyte, is mostly used in small  
power generation facilities. The above three fuel cells are low-temperature fuel cells operating  
at temperatures generally ranging from 80℃ to 200℃. Molten Carbonate Fuel Cell (MCFC)  
and Solid Oxide Fuel Cell (SOFC) are high-temperature fuel cells operating at temperatures  
generally ranging from 600℃ to 1000℃, with lithium potassium, lithium sodium carbonate or  
zirconia and yttria as electrolytes, respectively.  
The voltage supplied by a single fuel cell is limited, so many fuel cells need to be connected in  
series and parallel on a large scale to output higher voltage and high power. The theoretical  
voltage of the fuel cell depends on the standard potential difference of the reaction between  
the anode and cathode, and different fuels may generate different voltages. The theoretical cell  
voltage of the hydrogen fuel cell is 1.23V. In practice, the actual output voltage is usually only  
0.6V to 1.0V due to the influence of overpotential, internal resistance and mass transfer rate. To  
improve the output voltage and power of fuel cells, it is necessary to modularize different  
numbers of single cells connected in series and parallel according to the actual conditions,  
that is, to form a fuel cell stack. In addition to the stack, the fuel cell system also includes some  
necessary auxiliary devices, such as a fuel supply and circulation system, an oxidant supply  
system, a water management system, a thermal management system, a control system, and a  
safety system.  
Fuel cells and heat engines essentially convert chemical energy into other energy but in  
different ways. In terms of the operating principle, fuel cells and heat engines are also energy  
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The Development and Outlook of Green Hydrogen  
conversion devices that release chemical energy of fuels. The difference is that the fuel cell  
directly converts chemical energy into electricity, while the heat engine can only convert  
chemical energy of fuels into thermal energy. Therefore, fuel cells are not limited by the Carnot  
cycle limit and theoretically have higher energy conversion efficiency compared with the  
conversion process of chemical - thermal - kinetic - electricity of hydrogen fueled gas turbines.  
PEMFC commonly used in hydrogen vehicles operates at temperatures generally ranging from  
80℃ to 150℃ and has a theoretical efficiency limit of 80% to 85%. The high-temperature  
SOFC operates at temperatures generally ranging from 600℃ to 1000℃, has a theoretical  
efficiency limit of 50% to 65%, and is obviously superior to hydrogen fueled gas turbines.  
Limited by the technical level, it is difficult to reach the theoretical efficiency limit, especially the  
practical efficiency of low-temperature fuel cells is reduced significantly. Current common fuel  
cell systems are typically 40% to 60% efficient. In cogeneration, the comprehensive efficiency  
of fuel cells may reach over 80%.  
In terms of the full life cycle, the cost of a fuel cell system includes the stack, system  
components and other parts, with the stack usually costing more than 50%. For PEM fuel cells  
using platinum and other precious metals, the cost of catalysts accounts for more than half of  
the total cost. The cost of hydrogen fuel cells is currently high and is expected to fall rapidly  
with economies of scale and technological advances. According to the U.S. Department of  
Energy, for example, the production of 80kW PEMFC for hydrogen vehicles will increase from  
1000 to 10,000 units per year, and the cost of the fuel cell system will drop by more than 50%A.  
It is expected that economies of scale will remain the main driver of fuel cell cost reduction in  
the coming years. In the long run, technological progress is the intrinsic and fundamental  
driving force for improving the cost-effectiveness of fuel cells. For example, for PEM fuel cells,  
the high cost of precious metal catalysts and perfluorosulfonic acid membranes is the main  
factor driving up the cost. The key to cost reduction is to reduce the consumption of precious  
metals such as platinum, iridium and rhodium in the catalyst, and develop non-precious metal  
catalysts and low-cost non-fluorinated PEM. For high-temperature SOFC, the stack cost is  
expected to decrease further with the advancement of structural design and production  
process of electrolyte materials.  
The demand for fuel cells in power system applications and in vehicle applications differ  
significantly and the cost varies greatly. In order to improve the power density of cells, the  
service life of the vehicle battery is generally only about 10,000 hours, which is difficult to meet  
the requirements for long-term use of the power system. The power application is generally  
large in scale and requires megawatt power generation capacity, so a large number of modular  
fuel cells are required to be connected in series and parallel, and the difficulty in designing,  
manufacturing and controlling auxiliary equipment (such as thermal management, and material  
flow management) is greatly increased accordingly. At present, there are relatively few actual  
projects in power systems applying fuel cells for power generation, and fuel cells are mainly  
used for cogeneration or serve as the standby power supply of important facilities.  
A DOE. Department of Energy Hydrogen Program Plan. 2020.  
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Box 2.3  
Daesan Hydrogen Fuel Cell Power Plant in South Korea  
In July 2020, Daesan Hydrogen Fuel Cell Power Plant, the world’s largest hydrogen fuel  
cell power plant, was completed in Daesan Industrial Complex, Chungcheongnam-do,  
South Korea. The Plant covering an area of 20,000m2 is equipped with 114 sets of 440kW  
PAFCs, with a total installed capacity of 50MW.  
A feedstock which is the industrial by-product hydrogen is supplied to the Plant through  
pipeline transportation. No carbon emissions and environmental pollution will be  
produced during power generation, allowing a stable power supply throughout the year.  
At present, the whole system is running at more than 95% and provides 400GWh of  
electricity to 160,000 households per year. The Project is jointly constructed and  
operated by Doosan Fuel Cell Inc., Q CELLS and DongSeo Generation, and DongSeo  
Generation plans to expand the Plant to 1 GW by 2030.  
3. Hydrogen heating  
Like coal, gasoline, and natural gas, hydrogen can be burned to provide heat, mainly in  
hydrogen-fired boilers. Hydrogen can also be used for co-generation in the form of fuel cells to  
make full use of the residual heat of fuel cells, such as the Ene-Farm Project in JapanA.  
Hydrogen-fired boilers include hydrogen-fired heat boilers, hydrogen-fired heat medium  
heaters, hydrogen-fired molten salt furnaces, which are commonly used to process by-product  
hydrogen. For example, many chlor-alkali enterprises use hydrogen-fired boilers to produce  
steam by burning byproduct hydrogen. Hydrogen-fired boilers have higher safety  
requirements than gas and natural gas boilers. In order to ensure safety during ignition, the  
ignition system of the hydrogen-fired boiler usually adopts a secondary ignition method, such  
as igniting liquefied petroleum gas first and then hydrogen, and it is necessary to ensure that  
there is no hydrogen in the furnace before ignition. As a key component of the hydrogen-fired  
boiler, the combustion control system can ensure the stability of hydrogen combustion and the  
normal operation of the boiler by adjusting hydrogen flow, pressure, and hydrogen-to-air ratio.  
Other safety measures include: preventing backfire accidents with hydrogen LV protection  
switches, preventing electric valves from generating static electricity with pneumatic switches,  
purging the furnace with nitrogen before start-up and shutdown to avoid hydrogen buildup,  
and checking for hydrogen leaks with a hydrogen detector.  
There is a huge demand for heating in industrial, building and other fields. Generally speaking,  
electric heating technologies such as heat pumps tend to have higher efficiency and better  
economy for building heat or industrial heat with low demand temperature, while hydrogen  
heating is less competitive. The heat demand in the building field mainly includes space  
A In this project, a SOFC fuel cell is used in a household cogeneration system, which can provide power  
supply, space heating, and produce hot water.  
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The Development and Outlook of Green Hydrogen  
heating, hot water production or cooking, etc.. The hydrogen heating may be applied in the  
form of delivering hydrogen to users through blending hydrogen into natural gas pipeline  
network or dedicated hydrogen pipelines for direct combustion or delivering for combustion  
after cogeneration by fuel cells or hydrogen-to-methane. Some demonstration projects in  
Europe, Japan and other places are shown in Table 2.15.  
Table 2.15 Hydrogen Utilization Methods in the Building Field and Some Demonstration Projects  
Hydrogen  
utilization method  
Features  
Advantages  
Demonstration project  
The existing natural gas  
Most existing natural gas pipe  
Blending  
hydrogen into  
natural gas  
infrastructure can be used, network equipment can be  
and the hydrogen blending used, with less upfront  
ratio is generally 5% to 20% investment  
GRHYD Project in France,  
and HyDeploy Project in UK  
Existing natural gas pipeline  
network equipment can be  
The existing natural gas  
infrastructure can be used, used. Zero carbon emissions  
European STORE&GO  
projects (mainly located in  
Germany, Switzerland and  
Italy)  
Hydrogen to  
methane  
but new carbon dioxide  
capture equipment and  
methane chemical plants  
also need to be built  
can be achieved by using  
hydrogen produced from  
renewable energy and  
captured carbon dioxide as  
feedstocks  
Investment is needed to  
build new dedicated  
hydrogen pipeline networks  
Dedicated  
hydrogen  
pipeline network  
Zero carbon emissions can be  
achieved with less energy loss  
than methane synthesis  
H21 Project in UK (still in  
the test run stage)  
and other facilities  
Various energy services such  
as power and heat supply can  
be realized simultaneously, and  
the overall efficiency is high  
Investment is needed to  
build new facilities related to  
fuel cells  
Fuel cell  
cogeneration  
Ene-Farm Project in Japan  
In the field of high-quality industrial heat (such as cement, glass, and ceramics),  
hydrogen-fired boilers have some application potential to meet the heat demand with zero  
carbon emissions. According to the IEA, the world’s industrial demand for high-temperature  
heat in 2018 was about 1280 Mt of oil equivalent, mostly used in metallurgy, cement, ceramics,  
glass, and other industries. Fossil fuels are currently the main source of high-quality industrial  
heat, with about 65% from coal, 20% from oil, and 10% from natural gas. Hydrogen heating is  
an important scheme for the decarbonization of high-quality industrial heat. Its application  
prospect and potential still depend on the development of hydrogen heating technology and  
the decrease of hydrogen production cost.  
2.3.1.3 Traffic Industry  
Hydrogen energy substitute for fossil energy is one of the important ways to achieve carbon  
neutrality in the transportation sector. Hydrogen fuel cell technology is an ideal solution for  
decarbonization in some application scenarios in the transportation sector because of its  
advantages of stable operation at low temperature, short start-up time and fast charging speed.  
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Key Technologies for Green Hydrogen  
With the development and progress of fuel cell technology, hydrogen fuel cell vehicles,  
hydrogen aircraft and hydrogen ships will have great application prospects.  
1. Hydrogen fuel cell vehicle  
A hydrogen fuel cell vehicle consists of four basic modules: a powertrain, a chassis, vehicle  
electronics, and a vehicle body, and its structure is shown in Figure 2.31. The powertrain  
provides power for the vehicle through the fuel cell system and the electric motor. Hydrogen is  
stored in the pressure tank of the vehicle, and its chemical energy is converted into power  
through the fuel cell stack, so as to drive the electric motor supplemented by the cells. Apart  
from the powertrain, other components of the fuel cell vehicle are basically the same as those  
of a conventional vehicle. The chassis consists of transmission, steering, braking and driving  
systems, and vehicle electronics mainly consist of a chassis control system, a safety system, a  
communication system, etc..  
Figure 2.31 Structural Diagram of Fuel Cell Vehicle  
The operating principle of hydrogen fuel cell vehicles is shown in Figure 2.32. In addition to the  
fuel cell stack, the vehicle also includes four auxiliary systems: a hydrogen supply system, an  
air supply system, a water management system and a heat management systemA. The  
hydrogen supply system delivers hydrogen to the fuel cell stack to which oxygen is supplied by  
the air supply system consisting of an air filter, air compressor, and humidifier, and the water  
and heat management systems adopt separate water and coolant loops to eliminate waste  
A GreenWheel, Fuel Cell System and FCEVs Components.  
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The Development and Outlook of Green Hydrogen  
heat and reaction products. The heat management system can absorb heat from the fuel cells  
to heat the cab and improve vehicle efficiency.  
Figure 2.32 Relation Diagram of Main Modules of Fuel Cell Vehicle  
Hydrogen fuel cell vehicles (FCVS) are widely used in a variety of traffic situations, and there  
are FCVS products or prototypes for all vehicle types. Passenger vehicles have been applied  
commercially, and forklifts, buses and trucks are at the forefront of application in the field of  
commercial vehicles, with huge application potential in the future.  
Fuel cell bus is one of the most widely used fuel cell vehicles at present. The reason is that  
buses have a stable operation mode for the public and require fewer hydrogen refueling  
stations. Fuel cell buses have become the mode of transportation advocated by the green  
society. According to statistics, a large fuel cell bus, consisting of important components such  
as a fuel cell system, a battery system and a hydrogen storage system, costs about RMB 2  
millionA in 2020, and the acquisition cost structure is shown in Figure 2.33.  
Figure 2.33 Cost Structure of Fuel Cell Vehicle  
A Source: Zhongtong Bus, EV100plus.  
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Key Technologies for Green Hydrogen  
Fuel cell forklifts are a cutting-edge application of fuel cell technology. The forklift requires low  
output power and only operates in a small area, so it requires few hydrogen refueling stations  
(HRS) and has long-term stable operating efficiency. Fuel cell forklifts have been applied  
commercially, with more than 25,000 fuel cell forklifts in the United States in 2020.  
Fuel cell trucks have great development potential in intra-city and inter-city logistics. With a  
distance per charge of hundreds to one thousand kilometers, fuel cell trucks are able to  
complete most intra-city and inter-city cargo transportation and can be refueled with hydrogen  
in a short time, which greatly improves the operational efficiency of transport fleets.  
2. Hydrogen refueling station  
The construction of hydrogen refueling stations plays a key role in hydrogen transport.  
Improving the cost-effectiveness of hydrogen refueling can effectively reduce the terminal  
sales price of hydrogen and promote the commercialization of hydrogen vehicles. At present,  
181 hydrogen refueling stations have been built and under construction in China, including 57  
under constructionA. By 2020, 105 of the 124 hydrogen refueling stations built in China have  
clear refueling capacity, including 50 stations with a hydrogen refueling capacity of 500kg/day,  
20 stations with a hydrogen refueling capacity of 1000kg/day, and 7 hydrogen refueling  
stations with a hydrogen refueling capacity of greater than 1000kg/day.  
Key technical equipment of a hydrogen refueling station includes a hydrogen compressor, HP  
hydrogen storage devices, hydrogen dispensers, and a station control system. The process  
principle of a hydrogen refueling station is shown in Figure 2.34. The hydrogen transported to  
the hydrogen refueling station by means of gas and hydrogen trailers and liquid hydrogen  
tankers is delivered into a pressure regulating and metering device through pipelines and  
output at a stable pressure, and then dried by a drying system. The dried hydrogen is  
delivered into a compression system, pressurized by a hydrogen compressor, stored in HP  
storage tanks in the station, and then refueled in hydrogen fuel cell vehicles through hydrogen  
dispensers. The compression system determines whether to fill the HP storage system with  
hydrogen or to refuel the vehicle directly with hydrogen through the hydrogen sales system,  
depending on the current operating conditions.  
Figure 2.34 Flow Chart of Hydrogen Refueling  
A Senior Engineering Intelligence, Blue Book for the Development of Hydrogen and Electricity Industry in  
China in 2021 (Version 1.0)  
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The Development and Outlook of Green Hydrogen  
As the core equipment for hydrogen refueling of fuel cell vehicles, the hydrogen dispenser is  
equipped with a hydrogen refueling nozzle, a temperature and pressure sensor, an ambient  
temperature sensor, a metering device, a filling controller, a hose, an infrared data receiving  
module, etc. While ensuring the safe refueling of the on-board hydrogen storage cylinder, the  
hydrogen dispenser shall accurately display the amount of hydrogen refueled and figure and is  
provided with safety protection measures such as lightning protection and anti-static protection,  
which can realize functions such as emergency shutdown and overfilling prevention. At present,  
there are mainly 35MPa and 70MPa hydrogen dispensers, with the main technical  
requirements such as no overtemperature or overpressure during refueling, and the shortest  
possible refueling time. According to the safety refueling boundary requirements of the  
international standard ISO15869 for vehicle-mounted HP hydrogen storage systems, the  
operating temperature of the system shall not exceed 85℃ and the maximum flow rate shall be  
less than 60g/s during gaseous hydrogen refueling. The refueling pressure of 35MPa or 70MPa  
vehicle-mounted hydrogen storage cylinders shall not exceed 43.8MPa or 87.5MPa. The  
hydrogen refueling time of fuel cell vehicles is equivalent to that of traditional internal  
combustion engine vehicles, which is 3 min to 5 min.  
The station control system has the main functions of providing monitoring and control  
information for the entire process optimization management of the station, including data  
acquisition and processing of on-site process variables so as to further control the in-service  
conditions and parameters of the main equipment in the station, monitoring the running status,  
logical control and interlock protection of various process equipment and auxiliary system  
facilities, printing production reports, alarm and event reports, etc. The station control system is  
interlocked with the security system, and the gas-flame detection and alarm system.  
The hydrogen refueling station may be constructed in many technical routes, including the  
following types. There are two types classified by hydrogen source, namely external hydrogen  
supply stations and onsite hydrogen production stations. There are two types classified by the  
refueling pressure, namely 35MPa and 70MPa stations. There are three types classified by the  
moving method, namely fixed, skid-mounted and mobile stations. There is no onsite hydrogen  
production device in the external hydrogen supply station, so hydrogen is transported to the  
station through tube trailers, liquid hydrogen tankers, hydrogen pipelines, etc. The onsite  
hydrogen production station may be equipped with hydrogen production systems such as  
hydrogen production by water electrolysis and hydrogen production by natural gas reforming.  
During onsite hydrogen production, hydrogen is generally purified and dried by a PSA  
adsorption system, then compressed, stored and refueled. The technical routes of hydrogen  
refueling stations in two hydrogen supply modes are shown in Figure 2.35.  
The large-scale application of hydrogen fuel cell vehicles is based on the popularization and  
promotion of hydrogen refueling stations, and the future construction of hydrogen refueling  
stations requires further consideration of site selection, safety assessment and other factors.  
When selecting the type of hydrogen refueling station to be constructed, it is necessary to take  
into account a variety of factors in evaluating the technical economics of local hydrogen supply,  
including the size of the station, the size of the customer base, the feedstock supply chain and  
transportation costs.  
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Key Technologies for Green Hydrogen  
Figure 2.35 Two Technical Routes of Hydrogen Refueling Stations  
At present, the development mode of joint stations such as hydrogen/gasoline filling,  
hydrogen/gas filling, hydrogen refueling/charging, and hydrogen, gasoline, gas and power  
supply stations is an important way to give full play to the intensive advantages of joint stations  
and promote the application of hydrogen energy. The hydrogen refueling facilities are provided  
in the original or new petrol stations and gas stations so that the stations have multiple  
functions such as gasoline and gas filling and hydrogen refueling, which can avoid repeated  
construction and reduce the floor space. At present, several provinces and cities in China have  
introduced management acts to support the renovation and expansion of hydrogen refueling  
facilities using the existing network of gasoline and gas filling stations, and encourage the  
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The Development and Outlook of Green Hydrogen  
investment and construction of hydrogen refueling stations, such as Anting Hydrogen  
Refueling and Charging Station, Gasoline and Hydrogen Refueling Station in Xinxing County,  
Yunfu, West Shanghai Gasoline and Hydrogen Refueling Station, and Anzhi Gasoline and  
Hydrogen Refueling StationA.  
3. Hydrogen aircraft  
Traditional aviation gas turbine engines mostly use aviation kerosene, with inevitable CO2 and  
NOx emissions. Hydrogen power is an important solution for achieving carbon neutrality in  
aviation because it avoids greenhouse gas emissions such as CO2 and has the advantage of  
high energy density.  
At present, hydrogen aircraft is still in the stage of conceptual design and flight test. Airbus has  
unveiled its concept for a future hydrogen-powered aircraft called ZEROe powered by  
hydrogen hybrid energy, which uses improved hydrogen turbine engines and also generates  
electricity through hydrogen fuel cells to complement the turbine engines. This aircraft is  
expected to carry as many as 200 passengers with a range of about 3700km. In 2020,  
ZeroAvia, an American company, tested the world’s first hydrogen-powered commercial  
aircraft, at a flight speed of 185km/h and a power of about 230kW. It plans to retrofit 50−100  
seat regional aircraft with hydrogen fuel systems to provide hydrogen power by 2030.  
The core technology of hydrogen aircraft is the improvement and upgrading of its propulsion  
system. Hydrogen turbines and fuel cells are the two most important components of the  
hydrogen aircraft propulsion system.  
The structure of the hydrogen turbofan engine is shown in Figure 2.36, which is basically the  
same as the current aviation turbine engine. Hydrogen fuel is burned in the combustion  
chamber to drive the turbine and drive the fan to generate thrust.  
The hydrogen cell propulsion system is a power unit that can achieve zero pollutant emissions,  
with its structure shown in Figure 2.37. Water vapor condensation nuclei are rarely generated in  
the clean environment for electrochemical hydrogen-oxygen reactions in hydrogen fuel cells,  
which can greatly reduce the formation of wake clouds and the impact of flight on climate by  
75% to 90%.  
Figure 2.36 Schematic Diagram of Turbine Propulsion System for Hydrogen Aircraft  
A China EV100, China Hydrogen Industry Development Report 2020.  
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Key Technologies for Green Hydrogen  
Figure 2.37 Schematic Diagram of Fuel Cell Propulsion System for Hydrogen Aircraft  
In addition, the practical application of hydrogen aircraft requires the advancement of airborne  
hydrogen fuel storage technology and the improvement of hydrogen energy infrastructure at  
the airport.  
Airborne hydrogen fuel storage is dominated by liquid hydrogen storage. For short- and  
medium-range passenger aircraft, the existing airframe structure needs to be adjusted or  
redesigned, taking into account issues such as flight resistance and flight costs. For large,  
long-range passenger aircraft, new revolutionary fuselage design ideas such as wing-fuselage  
fusion design and box-type wing structure need to be introduced to improve the utilization of  
the aircraft’s internal space structure.  
The hydrogen energy infrastructure at the airport mainly includes liquid hydrogen fuel  
transportation, storage and refueling equipment. Compared with fossil fuels, the liquid  
hydrogen refueling process is complicated, time-consuming, and high in safety risks, which  
increases the aircraft refueling time and operating costs at the airports. Therefore, efficient  
refueling technology and refueling system should be developed for liquid hydrogen fuel.  
4. Hydrogen ships  
Ship navigation is mainly powered by marine diesel engines, with problems such as low energy  
conversion efficiency, large vibration and noise of diesel engines, and serious combustion  
emissions. PEMFC, SOFC and other fuel cell technologies have the advantages of high  
conversion efficiency, low vibration and noise, cleanness and no pollution, and become an  
important development trend for future hydrogen vessels.  
Independent electric propulsion device is the most common propulsion mode in the electric  
propulsion modes of ships, and the propeller is driven by the propulsion motor. Ships often sail  
in variable operating conditions in the ocean, and fuel cells respond slowly to the control  
requirements of output changes and cannot meet the transient energy demand of motors. In  
order to improve the stability and flexibility of the power supply system, the fuel cell system  
generally needs to work with the battery system, and the basic structure is shown in Figure 2.38.  
The fuel cell power system can power motors separately and reserve excess power by  
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The Development and Outlook of Green Hydrogen  
charging the battery when its output power meets the power demand of the ship’s operating  
conditions. The fuel cells may work together with the battery pack to power the propulsion  
motors when the power production fails to meet the demand of operating conditionsA.  
Figure 2.38 Structure Layout of Whole Hydrogen Ship System  
The application of fuel cells in commercial ships and passenger ships has gained increasing  
attention, and the fuel cells have good application prospects in LNG ships, yachts and small  
passenger ships, and scientific research shipsB. In 2008, Alsterwasser, a 48kW PEMFC  
passenger ship launched by Zemships in Germany, was officially put into operation, which is  
the first fuel cell-powered passenger ship put into operation in the worldC. In 2017, the Energy  
Observer, developed by France, was officially launched and began its round-the-world voyage.  
The ship’s fuel cell uses hydrogen fuel produced by solar and wind energy water electrolysis  
units and stored in storage cylinders. It is the first ship in the world that can realize shipborne  
hydrogen production. In 2015, Toda Corp. and Yamaha Motor Company jointly developed a  
hydrogen fuel cell ship and carried out trials on fishing boats. The ship has a maximum speed  
of 37km/h and a range of about 70km per hydrogen refueling.  
2.3.1.4 Metallurgical Industry  
There are generally many types of industrial metallurgical processes for refining metals, such  
as pyrometallurgy (dry metallurgy), hydrometallurgy, and electrometallurgy. Pyrometallurgy is  
the most widely used, and the reducing agents used mainly include coke, natural gas,  
hydrogen, active metals, etc. Hydrogen, as a reducing agent, can in principle smelt some  
metal oxides with less heat of formation, such as copper oxide, and iron oxide, but it cannot  
reduce aluminum oxide, magnesium oxide with much heat of formation. At present, metals  
such as molybdenum and tungsten are generally smelted by hydrogen in industry, with small  
consumption. With the demand for low-carbon energy transition and development in the  
metallurgical industry, hydrogen ironmaking technology has attracted much attention in recent  
years. At the same time, steel is the main feedstock for all industries and is in great demand, so  
there will be great application potential of hydrogen steelmaking technology in the future.  
A Kang Jialun, et al. Shanghai Energy Conservation [J]. China Engineering Science, 2021, 04:414-421.  
B S. U. Jeong, Power Sources, 2005，144(1): 129-134.  
C Guo Hao. Official Release of Hydrogen Energy Roadmap in Europe and South Korea [J]. Energy Research  
and Utilization, 2019, 186(02):28.  
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Key Technologies for Green Hydrogen  
There are two different processes for steelmaking: blast furnace ironmaking + converter  
steelmaking and electric steelmaking, as shown in Figure 2.39. The first process mainly adopts  
iron ore as feedstock and coke and coal as reductant and fuel, with a lot of carbon emissions in  
the production process. The second process mainly adopts steel scrap and direct reduced  
iron (DRI) as feedstock and carries out steelmaking by electric furnaces.  
Figure 2.39 Steelmaking Flow Chart  
Hydrogen can replace the currently widely used fossil resources such as coal and natural gas  
in the production of DRI as a reducing agent, which can significantly reduce carbon emissions  
during steelmaking. The main reactions of reducing iron oxides with hydrogen are:  
3Fe2O3 + H2 = 2Fe3O4 + H2O  
Fe3O4 + H2 = 3FeO + H2O  
FeO + H2 = FeO + H2O  
Fe3O4 + 4H2 = 3Fe + 4H2O  
Compared with the coke blast furnace ironmaking process, the hydrogen ironmaking process  
has the main advantages of short process, low energy consumption, omitted high energy  
consumption and high pollution processes such as coking and sintering, fewer carbon  
emissions which may be theoretically zero carbon emissions, fewer pollutant emissions such  
as nitrogen oxides, sulfur oxides and respirable particulate matter. Compared with common  
reducing agents, hydrogen has a faster reduction reaction rate and diffusion rate, and its  
movement direction and transfer path change rapidly in the furnace, so it cannot be well  
retained for the reaction, and only 30%−50% of the total hydrogen in the furnace can  
participate in the reduction reaction. The challenge to be overcome in hydrogen refining is to  
improve hydrogen utilization accordingly. In addition, it is necessary to accumulate experience  
in operation and management to determine whether to adopt the shaft furnace or the fluidized  
bed furnace for hydrogen ironmaking.  
In 2019, the global DRI production reached 108 Mt, with about 60% produced by the MIDREX  
process. There are two technical routes for hydrogen ironmaking, namely hydrogen-rich  
ironmaking and pure hydrogen ironmaking. Hydrogen-rich ironmaking projects include  
COURSE50 in Japan, and Hydrogen-rich Blast Furnace Project of Thyssenkrupp Steel Plant in  
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The Development and Outlook of Green Hydrogen  
Duisburg, Germany. Pure hydrogen ironmaking projects include SALCOS Project of Salzgit  
Steel in Germany, H2FUTURE Project of Veostalpine in Austria, and HYBRIT Project of Lulea  
SSAB in Sweden. HBIS Group and Central Iron & Steel Research Institute of China have also  
carried out a series of research on hydrogen-rich and pure hydrogen ironmaking processes.  
The pure hydrogen ironmaking process is shown in Figure 2.40.  
Figure 2.40 Comparison of Pure Hydrogen Ironmaking Process and Conventional  
Blast Furnace Ironmaking Process  
2.3.1.5 Other Industries  
In addition to the main applications mentioned above, other applications of hydrogen include  
aerospace, electronics, pharmaceutical synthesis, food processing and so on.  
1. Spaceflight  
Hydrogen has a very high energy density, with a calorific value per unit mass three times that of  
gasoline, which is extremely beneficial for reducing the dead weight of rockets and space  
shuttles. Liquid hydrogen was first used as a space fuel in 1960. At present, hydrogen is mostly  
used as the engine propellant for space shuttles and stored in external propellant tanks in the  
form of liquid hydrogen, with the consumption of about 1450m3 (100t) of liquid hydrogen per  
launch. The third sub-stage of China’s Long March-3 Series Launch Vehicle adopts liquid  
hydrogen as a propellant and liquid oxygen as an oxidant, and the startup of the hydrogen  
engine may be enabled several times. The propulsion system consists of a YF-75  
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Key Technologies for Green Hydrogen  
hydrogen-oxygen engine, a conveying system, a pressurization system, a propellant utilization  
system, and a propellant management system.  
2. Electronics industry  
In the semiconductor industry, hydrogen is mainly used in the preparation of high purity silicon,  
including crystal growth and substrate preparation, oxidation process, epitaxy process, and  
chemical vapor deposition (CVD) process. In the semiconductor industry, hydrogen is required  
to be high in purity. Since trace impurities may change semiconductor characteristics, the  
content of impurities such as oxygen, water and carbon dioxide in hydrogen needs to be  
strictly controlled. For example, in the epitaxy process, silicon tetrachloride or trichlorosilane  
reacts with hydrogen on the surface of the heated silicon substrate, and silicon is deposited on  
the silicon substrate by reduction to generate the epitaxial layer. The relevant chemical  
reactions are as follows:  
SiCl4 + 2H2 = Si + 4HCl  
SiHCl3 + H2 = Si + 3HCl  
In addition, high purity hydrogen is required for the deposition process of amorphous silicon  
film solar cells and the rod making process of quartz glass optical fibers.  
2.3.2 Technology Comparison  
2.3.2.1 Green Hydrogen-to-ammonia and Conventional Ammonia Synthesis  
Green hydrogen-to-ammonia has a promising future. In 2019, the global annual production of  
ammonia synthesis was about 160 Mt, consuming 30 Mt of hydrogen per year. The annual  
growth rate is expected to be 1.8% in the next five yearsA. As the current ammonia synthesis  
process uses fossil fuels such as natural gas and coal for hydrogen production, which  
consumes a lot of fossil fuels and causes high carbon emissions, the future ammonia industry  
will also face the problem of the low-carbon energy transition. At present, the carbon emission  
from the coal-to-ammonia process is about 4.2 times the ammonia production, and the carbon  
emission from the natural gas-to-ammonia process is about 2 times the ammonia production.  
The most realistic and feasible way to achieve the decarbonization of the ammonia synthesis  
industry is to produce hydrogen from renewable energy and water electrolysis rather than from  
coal and natural gas in ammonia synthesis, which is called green ammonia. Relevant  
demonstration projects have been completed in Japan, Germany and other places.  
With the rapid decline in the cost of renewable energy power generation, green ammonia has  
gradually become economically viable. The current lowest winning tariff for PV projects in  
China is already below RMB 0.25/kWhB. At that tariff level, the cost of green ammonia is  
between RMB 3.8 and 4/kg, which is close to the market price of ammonia (nearly RMB 3/kg). If  
the cost of carbon emission (at RMB 50/t) is included, the cost of ammonia production from  
A Source: IHS Markit.  
B The bid electricity price for the 2020-15# plot project in Hainan Prefecture, Qinghai Province in 2020 is RMB  
0.2427/kWh.  
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The Development and Outlook of Green Hydrogen  
fossil fuels will be increased by RMB 0.1−0.2/kg, and the cost of green ammonia production will  
be further close to that of ammonia production from fossil fuels. By 2060, the cost of green  
ammonia production is expected to drop to RMB 2.4/kg, and the cost-effectiveness is  
expected to exceed that of conventional ammonia production from natural gas and coal, and  
even better if the cost of carbon emission is taken into account, making it the most competitive  
ammonia synthesis method and be widely promoted. Green ammonia production will be as  
popular as the coal-to-ammonia process and gas-to-ammonia process today.  
Hydrogen storage technology in green ammonia production is expected to solve the problem  
of mass hydrogen storage. Hydrogen has a small molecular size and low boiling point, takes  
up a lot of space for mass storage, and escapes easily. Hydrogen and nitrogen are combined  
to produce ammonia, and liquid ammonia is used as the carrier of hydrogen energy for storage,  
transportation or utilization, which can effectively reduce the storage difficulties and cost  
compared with direct hydrogen storage. For another, there are some shortcomings during  
hydrogen storage in green ammonia production, e.g., ammonia itself is corrosive and toxic,  
and the total energy efficiency of the hydrogen-ammonia-hydrogen process is low. So, the  
technology needs to be further improved in the future.  
Box 2.4  
Green Ammonia Energy  
Since this century, more and more countries have paid attention to the R&D of ammonia  
fuel. Ammonia energy has the following advantages: First, ammonia is high in volume  
energy density, with the calorific value close to that of methanol, and the energy density  
of ammonia per unit volume is 1.5 times that of liquid hydrogen of the same volume.  
Second, ammonia produces zero carbon emissions, ammonia, like hydrogen, is a  
zero-carbon energy source, and is ideally burned to produce nitrogen and water, with no  
additional carbon emissions. Third, it is easy for storage, transportation and supply.  
There have been many studies on the application of ammonia in the field of energy,  
including direct use as fuel for fuel cells and engines, and as fuel for gas turbines in  
stationary power generation, but there are still many drawbacks in practice, which  
restrict its large-scale promotion and application.  
Ammonia is poor in combustion characteristics. Ammonia is less active, difficult to be  
ignited, and slow to burn, so when actually used as fuel, it needs to be added with  
combustion aids, such as acetylene and dimethyl ether, or added to gasoline, coal and  
natural gas for co-combustion. The energy density and combustion characteristics of  
liquid ammonia are compared with those of other liquid fuels in the following table.  
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Key Technologies for Green Hydrogen  
Box 2.4 Table Comparison of Combustion Characteristics of Different Liquid Fuels  
Higher  
calorific  
value  
Higher  
calorific  
value  
Laminar  
burning  
velocity  
Minimum  
ignition  
energy  
Ignition  
temperature  
Item  
(℃)  
(MJ/kg)  
(MJ/L)  
10.1  
15.3  
18.0  
34.0  
(m/s)  
3.51  
0.07  
0.36  
0.58  
(MJ)  
0.011  
8
Liquid hydrogen  
Liquid ammonia  
Methyl alcohol  
Gasoline  
142  
571  
651  
470  
220  
22.5  
22.7  
46  
0.14  
0.28  
Exhaust gas pollution. Polluting nitrogen oxide gases will inevitably be produced when  
ammonia turbines and ammonia fuel cells operate, especially when pure ammonia fuels  
or blended fuels with high ammonia content are adopted, so there is a need to provide  
an exhaust gas treatment system additionally.  
Corrosion. Ammonia is corrosive to copper, aluminum and other metals, so the corrosion  
resistance of engines is required. In addition, ammonia can damage the PEM of fuel  
cells and may cause serious nitrogen oxide pollution when applied to high-temperature  
solid oxide fuel cells, so direct ammonia supply type fuel cells almost adopt the alkaline  
fuel cell technology only, or indirect ammonia supply type fuel cells (i.e., ammonia is first  
decomposed into hydrogen and nitrogen, and hydrogen is used as fuel for fuel cells) are  
adopted, with limited overall energy utilization efficiency.  
Toxicity. Ammonia is toxic and is a hazardous chemical. It is necessary to ensure that no  
safety risks occur in the storage, transportation and application of liquid ammonia.  
Green ammonia can serve as the raw material of chemical fertilizers and other chemicals and  
also has certain application potential in the field of energy. Ammonia is a hydrogen-rich  
compound that can be used as a fuel of fuel cells or ammonia-doped gas turbines for power  
generation. In the direct ammonia fuel cell (DAFC), the redox reaction between ammonia and  
oxygen produces water and nitrogen, while releasing electricity and heat. Due to the stable  
molecular structure of ammonia, more activation energy is required to make ammonia react,  
and the efficiency of the DAFC is lower than that of the hydrogen fuel cell. Ammonia-doped gas  
turbines can reduce CO2 emissions based on existing gas generation technologies. However,  
direct combustion of ammonia in gas turbines will lead to an increase in nitrogen oxide (NOx)  
emissions (about 100 times that of natural gas), which needs to be solved in the future by  
developing highly selective catalytic reduction technology and innovative combustor design.  
2.3.2.2 Green Hydrogen Chemical Industry and Conventional Chemical Industry  
The main difference between the green hydrogen chemical industry and the conventional  
hydrogen-related chemical industry is that grey hydrogen produced from fossil fuels in the  
087  
The Development and Outlook of Green Hydrogen  
original chemical production process is replaced by green hydrogen produced from  
renewable energy. Compared with the conventional chemical industry, on one hand, the green  
hydrogen chemical industry reduces the demand for fossil fuels in the process of hydrogen  
production as well as the CO2 emissions from hydrogen production; on the other hand, it may  
also be used together with the CCUS technology to synthesize high value-added organic  
compounds such as methane and methanol through the reaction of hydrogen with carbon  
dioxide emissions from other fields, with the effect of carbon sequestration and negative  
carbon emissions. The technologies of hydrogen production and utilization involved in the  
green hydrogen chemical industry have been relatively mature, but the cost of green hydrogen  
production is still relatively high at present, so its application scale and promotion degree  
mainly depend on the comparative cost-effectiveness of green hydrogen to grey hydrogen.  
With the rapid decline of the cost of clean energy power generation and electrolytic hydrogen  
production equipment, and the limitation of carbon emission under the background of carbon  
neutrality, the cost-effective advantages of the green hydrogen chemical industry compared  
with the traditional chemical industry will become increasingly prominent in the future.  
1. Methanol synthesis  
In 2019, the global annual output of methanol was 82 Mt, and the annual hydrogen  
consumption was about 12 Mt. According to IEA projection, the global hydrogen consumption  
for methanol production is expected to increase by 3.6% annually in the next decade and  
reach 19 Mt by 2030A. At present, the carbon emissions from coal to methanol are about 3.5  
times that of methanol production, and those from natural gas to methanol are about 1.8 times  
that of methanol production. Similar to ammonia synthesis, methanol production can also use  
green hydrogen produced by the electrolysis of water from renewable energy to generate  
electricity, and then combine with CCUS technology to produce methanol through the  
hydrogenation of carbon dioxide, i.e. electrosynthesis of methanol.  
At present, the process of hydrogenation of carbon dioxide to methanol still has some defects,  
such as low one-way conversion rate, easy deactivation of catalyst and low energy exchange  
efficiency. Based on the current average price of green hydrogen, the cost of methanol  
produced is RMB 6−8/kg, which is much higher than the cost of methanol production from coal  
and natural gas (RMB 1.6−2.3/kg, considering the cost of carbon emission of about RMB  
2−2.5/kg). With the advancement of technology, the equipment cost of electrosynthesis of  
methanol has much room for reduction. Under the combination of reduced green hydrogen  
costs and advances in the electrosynthesis of methanol, green hydrogen is expected to be  
applied in a wider range in the synthesis of methanol. It is expected that by 2030, the cost of  
electrosynthesis of methanol will be close to that of natural gas to methanol. If the carbon  
emission cost (calculated by RMB 50/t) is considered, the costs of the two are roughly the  
same, and electrosynthesis of methanol will be applied in the energy field. By 2060, the  
electrosynthesis of methanol will form a comparative advantage over traditional fossil fuels  
preparation and become an important synthetic liquid fuel. At the same time, many  
downstream industries will be fully developed, and the electricity-based raw material industry  
with clean energy as driving force and water and carbon dioxide as “food” is heading for  
thousands of households.  
A Source: IEA, The Future of Hydrogen, 2019.  
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Key Technologies for Green Hydrogen  
Box 2.5  
Methanol Fuel Technology  
Methanol is an important liquid fuel in addition to being used as raw material. Methanol  
fuel has the following characteristics:  
1. Low carbon emissions. Methanol is the liquid fuel with the highest hydrogen content  
at room temperature, and its carbon emission is 10%−20% lower than that of gasoline  
and diesel oil at the same calorific value. In theory, zero carbon emission can be  
achieved if methanol is produced by electrosynthesis or biomass.  
2. Methanol fuel can significantly reduce NOx and carbon fume emissions compared to  
gasoline and diesel engines.  
3. Methanol is easy to store, and the construction cost of a methanol refueling station is  
low (currently only equivalent to 1/8 of the HRS of the same scale).  
The research on the application of methanol as fuel began in the 1970s. Western  
countries and China have carried out a lot of work on methanol as a fuel for automobile  
engines, including two technical routes of blending methanol and pure methanol. When  
methanol is mixed in gasoline and diesel at a lower proportion (e.g. 15%−30%), the  
gasoline and diesel engine systems may not be greatly changed; pure methanol fuel  
requires a special methanol fuel engine system. In practice, methanol fuel, especially  
pure methanol fuel, also exposes a range of problems:  
1. The energy density of methanol per unit volume is only half of that of gasoline and  
diesel, and cars are required to be equipped with larger fuel tanks under the same  
cruising range.  
2. The latent heat of vaporization of methanol is large, which makes cold start difficult.  
3. Methanol will accelerate the swelling and aging of rubber parts, and it is highly  
corrosive to metal parts.  
4. The self-lubricating property of methanol is worse than that of gasoline and diesel,  
and it will destroy the lubricity of engine oil.  
5. The nozzles of pure methanol engines are easily clogged.  
In view of the above problems, research institutes and related enterprises in various  
countries have carried out a lot of studies and made some breakthroughs. Solutions  
include: starting with gasoline or diesel, or heating the intake air during starting to solve  
the cold start problem; adopting alcohol-resistant rubber and parts; improving corrosion  
and lubrication problems through additives such as amine lubricants and alkaline  
corrosion inhibitors; developing special nozzles and filtering the oil system to improve  
nozzle clogging.  
089  
The Development and Outlook of Green Hydrogen  
The research on methanol fuel in China began in the 1980s. At present, Geely Auto,  
Yutong Bus and other automobile and engine manufacturers have made important  
progress in the field of methanol vehicles. Geely Auto has achieved mass production of  
pure methanol fuel vehicles. According to the relevant data, the current use cost of pure  
methanol fuel vehicles (including energy cost and maintenance cost) is better than that  
of traditional gasoline vehicles, as shown in the figure below. In the future, the application  
of electrosynthesis of methanol and biomass to methanol will make methanol vehicles  
more low-carbon and environmentally friendly, and play a unique role in the process of  
the energy transition.  
Box 2.5 Figure Comparison of 300,000km Usage Cost of Different Types of Automobiles  
2. Synthetic ethylene  
Ethylene is one of the most important basic organic chemical raw materials. In 2019, the global  
ethylene output reached 170 Mt, and about 80% of ethylene was produced by naphtha/diesel  
cracking to olefins. Methanol production from green hydrogen and olefin production from  
methanol is a new technological route for the green production of ethylene.  
The cost of ethylene production from green hydrogen is very sensitive to electricity price, and  
the electricity cost accounts for 60%−70% of the total cost. At the current level of technology  
and electricity price, the cost of green hydrogen to ethylene is about RMB 15/kg, much higher  
than that of naphtha cracking to ethylene (RMB 6/kg). It is expected that by 2060, the cost of  
clean energy power generation will be greatly reduced, technologies such as the electrolysis of  
water, methanation system, and methanol to olefins will become mature, and the cost of green  
hydrogen to ethylene is expected to be lower than that of naphtha cracking to ethylene, which  
will be promoted and applied in raw material demand terminals.  
2.3.2.3 Fuel Cells and Hydrogen Fueled Gas Turbines  
Fuel cells and gas turbines are both technical means to realize hydrogen power generation.  
Fuel cell power generation has the advantages of small equipment volume, high power density,  
strong modular performance, good scenario adaptability, no pollution, low noise, flexible  
090  
2
Key Technologies for Green Hydrogen  
configuration, etc.. It can be used as a supplement to the main electricity sources or as the  
main electricity source for islands, mountainous areas, and remote areas, and is expected to  
be promoted under the distributed application scenario.  
Hydrogen fueled gas turbine generation has the advantages of large united capacity,  
providing rotational inertia for the system, being upgradable from natural gas turbines, etc. It is  
suitable for supporting electricity sources and peakload regulating electricity sources for load  
centers, to ensure the safe and stable operation of a high-proportion clean energy power  
system in the future. The comparison of technical and economic parameters related to fuel cell  
and hydrogen fueled gas turbine power generation is shown in Table 2.16.  
Table 2.16 Technical and Economic Comparison of Fuel Cell and  
Hydrogen Fueled Gas Turbine Power Generation  
Cost of equipment  
investment  
Efficiency of power  
generation  
Item  
Unit capacity  
Power density  
2−5kW/L  
Not exceed 10MW  
in general  
1500−3000  
RMB/kW (alkaline stack)  
Fuel cell  
40%−60%  
35%−43%  
Hydrogen fueled  
gas turbine  
No large-scale commercial  
application yet  
10−600MW  
About 0.1kW/L  
In terms of cost-effectiveness, the current cost of fuel cell power generation equipment based  
on alkaline stack is RMB 3000/kW. In the future, the fuel cell power generation system will be  
upgraded from alkaline stack to high-temperature oxide stack with higher efficiency. With the  
increase of application scale, the cost of fuel cell power generation equipment is expected to  
decrease to RMB 800−1000/kW by 2050, taking into account the cost of systems including  
auxiliary equipment and other facilities of RMB 1500−2000/kW. At present, there is no  
large-scale commercial application of pure hydrogen fueled gas turbines. With reference to  
natural gas power generation, it is expected that the cost of a hydrogen fueled gas turbine will  
be equivalent to that of natural gas turbine when the technology of hydrogen fueled gas  
turbines is mature in the future. By 2050, the cost of a hydrogen fueled gas turbine is expected  
to reach about RMB 2000/kW and the cost of a power generation system is about RMB  
3000/kW.  
In terms of united capacity, the united capacity of the gas turbine can vary from 10MW to  
hundreds of MW. The fuel cell is small in size and large-scale application requires a large  
number of modules to be connected in series and in parallel, with high requirements for system  
control and reliability. Therefore, the hydrogen fuel cell power station is small in size, generally  
less than 10MW, and has more advantages in distributed power generation.  
In terms of generation efficiency, gas turbine technology is mature. At present, the generation  
efficiency of a heavy gas turbine is 35%−42%, and it is difficult to make a big breakthrough in  
the future. The fuel cell is not limited by the Carnot cycle limit of the heater and has higher  
energy exchange efficiency in theory. At present, the generation efficiency of the commercial  
demonstration project is generally 40%−60%. With the development of theoretical research  
and the innovation of fuel cell preparation technology in the future, the generation efficiency is  
expected to be further improved.  
091  
The Development and Outlook of Green Hydrogen  
In terms of power density, gas turbines are generally larger in size and have a lower power  
density per unit volume; with the development of vehicle fuel cell technology, the current power  
density of fuel cells is higher, which is dozens of times that of gas turbines. For stationary  
power generation, the power density has little impact; while in vehicle power or some  
distributed application scenarios, fuel cell technology with high power density has certain  
advantages.  
2.3.2.4 Hydrogen Fuel Cell Vehicles and Electric Vehicles  
To build a zero emission transportation system, hydrogen fuel cell vehicles and electric  
vehicles can be used to replace traditional fuel vehicles, which has become an important  
development trend of onshore transportation.  
The main difference between hydrogen fuel cell vehicles and BEVs is the source of electricity in  
the power system. As shown in Figure 2.41, all the energy of a BEV comes from its battery pack,  
which is charged outside the charging pile; the electricity for hydrogen fuel cell vehicles comes  
from the generation of hydrogen storage tanks and fuel cell stacks, and the hydrogen storage  
tanks are filled with hydrogen at the HRS. The power source of electric vehicles is lithium  
batteries, and the current technology is relatively mature, which has been widely used in the  
field of small passenger cars. The power source of a hydrogen fuel cell vehicle is hydrogen fuel,  
which is essentially the physical energy carrier obtained from the outside. Similar to gasoline, it  
has the advantages of high energy density, long battery life, fast replenishment speed and high  
comprehensive transportation efficiency, and has certain advantages in the fields of  
long-distance cars and trucks in theory. The following makes a comparison among hydrogen  
fuel cell vehicles, BEVs and traditional diesel and petrol vehicles in terms of energy exchange  
efficiency, cost-effectiveness, carbon emissions and safety.  
In terms of energy exchange efficiency, hydrogen fuel cell vehicles need to go through the  
energy exchange process of electricity-hydrogen energy-electricity-mechanical energy, with  
many links and low total energy efficiency. However, electric vehicles only have the process of  
energy exchange from electricity to mechanical energy, with the highest total energy efficiency.  
The comparison of energy efficiency between hydrogen fuel cell vehicles and BEVs and  
gasoline vehicles is shown in Table 2.17.  
Figure 2.41 Comparison of the Power System Structure  
Between Hydrogen Fuel Cell Vehicles and BEVs  
092  
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Key Technologies for Green Hydrogen  
Table 2.17 Comparison of Energy Efficiency Between Hydrogen Fuel  
Cell Vehicles and BEVs and Gasoline Vehicles  
Type  
Hydrogen fuel cell vehicle  
Pure electric vehicle  
—
Gasoline vehicles  
—
electrolytic hydrogen  
production 70%  
Hydrogen transportation  
and distribution 90%  
Power transmission and  
distribution 92%  
—
Energy efficiency of  
each link  
Fuel cell 50%  
Motor 90%  
28%  
Lithium-ion battery 95% Processing of gasoline 91%  
Internal combustion engine  
Motor 90%  
35%  
Total energy efficiency  
79%  
32%  
Note: regardless of the energy efficiency of crude oil extraction and other processes, the electricity used by  
electric vehicles and electrolytic hydrogen production is generated from renewable energy.  
In terms of cost-effectiveness, the current cost of hydrogen fuel cell vehicles is higher than that  
of BEVs and traditional diesel and petrol vehicles, which is mainly related to the current high  
cost of hydrogen fuel cell systems. In terms of operating cost, according to the current  
hydrogen price at HRSs, charging price of electric vehicles and oil price of gas stations, the  
100km fuel cost of BEVs is the lowest, and the 100km fuel cost of hydrogen fuel cell vehicles is  
higher than that of gasoline and diesel vehicles. With the decline in green hydrogen costs and  
the development of hydrogen storage and transportation technologies, there is great space for  
the decline in fuel costs of hydrogen fuel cell vehicles, but it is difficult to form a competitive  
advantage over BEVs in the field of small passenger cars. The comparison of  
cost-effectiveness between hydrogen fuel cell vehicles and BEVs and traditional diesel and  
petrol vehicles is shown in Table 2.18、Table 2.19.  
Table 2.18 Comparison of Cost-effectiveness Among Small Passenger  
Hydrogen Fuel Vehicles, Electric Vehicles and Gasoline Vehicles  
Type  
Hydrogen fuel vehicles Pure electric vehicle Gasoline vehicles  
Cost of vehicle purchase (RMB 10,000)  
50  
30  
20  
Energy consumption per one hundred  
kilometers  
1kg hydrogen  
16kWh of electricity  
7L gasoline  
Unit price of fuel  
RMB 60/kg  
60  
RMB 1/kWh  
16  
RMB 6/L  
42  
Fuel cost per 100 km (RMB)  
Table 2.19 Comparison of Cost-effectiveness Among Hydrogen Fuel  
Vehicles, Electric Vehicles and Diesel Vehicles for Public Transit  
Type  
Hydrogen fuel vehicles Pure electric vehicle  
Diesel truck  
45  
Cost of vehicle purchase (RMB 10,000)  
220  
170  
Energy consumption per one hundred  
kilometers  
7.4kg hydrogen  
120kWh of electricity  
42L diesel oil  
Unit price of fuel  
RMB 60/kg  
444  
RMB 1/kWh  
120  
RMB 6.1/L  
256  
Fuel cost per 100km (RMB)  
093  
The Development and Outlook of Green Hydrogen  
In terms of carbon emissions, both hydrogen fuel cell vehicles fueled by green hydrogen and  
BEVs using zero-carbon electricity can achieve zero carbon emissions during operation. The  
carbon emissions of BEVs that use coal-fired electricity are close to those of gasoline vehicles,  
and the carbon emissions of hydrogen fuel cell vehicles that use coal-to-hydrogen even  
exceed those of gasoline vehicles. Therefore, the development of zero-carbon electricity and  
green hydrogen is crucial to achieving carbon neutrality in the transportation sector. The  
comparison of 100km carbon emissions of hydrogen fuel cell vehicles, BEVs and gasoline  
vehicles is shown in Table 2.20.  
Table 2.20 Comparison of Carbon Emissions of Hydrogen Fuel Cell  
Vehicles, Electric Vehicles and Gasoline Vehicles  
Gasoline  
vehicles  
Hydrogen fuel cell vehicle  
Pure electric vehicle  
Type  
Green  
Coal to  
Zero-carbon  
Coal power  
13  
—
hydrogen  
hydrogen  
electricity  
CO2 emission (kg/100km)  
0
20  
0
16  
In terms of safety, Toyota and other automobile companies have verified the safety of hydrogen  
fuel cell vehicles, and completed a series of safety tests, such as hydrogen diffusion simulation  
test, combustion dynamic test with hydrogen on fire, ignition test for small leaks in pipelines,  
ignition test of hydrogen remaining in a certain part of the vehicle after hydrogen leakage,  
ignition test assuming that hydrogen is full in the compartment, ignition test of hydrogen  
released by safety valve and so on. The results show that the safety of hydrogen fuel cell  
vehicles can reach the level of diesel and petrol vehicles under specified safety measures.  
However, the safety of hydrogen fuel cell vehicles in closed spaces has not been reliably  
verified. In order to avoid the risk of explosion caused by hydrogen accumulation in closed  
spaces, hydrogen fuel cell vehicles are generally not allowed to park in closed places such as  
underground parking lots.  
2.3.2.5 Hydrogen Steelmaking and Traditional Steelmaking  
Carbon emissions from the global iron and steel industry account for 7% of the total carbon  
emissions, among which the reduction process of blast furnace ironmaking produces about  
90% of carbon emissions. Iron and steel companies such as Arcelor, China Baowu Iron and  
Steel Group Co., Ltd., SSAB and ThyssenKrupp have all set the goal of net-zero carbon  
emissions by 2050. In addition to the CCUS technology, the combination of hydrogen-based  
DRI + electric furnace steelmaking is considered the most feasible technical solution for  
decarbonization in the steel industry. At present, electric furnace steel accounts for about 30%  
of the world’s total steel output. By promoting green hydrogen ironmaking + electric furnace  
steelmaking, the electrification rate of the steel industry can be improved and the carbon  
emissions can be significantly reduced. According to estimates, the traditional blast  
furnace-converter process can emit about 2 tons of carbon dioxide per ton of steel; green  
hydrogen ironmaking + electric furnace steelmaking can achieve zero-carbon emissions in the  
steelmaking process under the condition of using clean electricity. The carbon emissions and  
comparison of different paths in iron and steel smelting are shown in Figure 2.42.  
094  
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Key Technologies for Green Hydrogen  
Figure 2.42 Comparison of Carbon Emissions in Different Steel Smelting Paths  
According to the demonstration project, the hydrogen consumption per ton of steel in  
hydrogen steelmaking is about 70kg hydrogen/ton of steel. According to the green hydrogen  
cost of RMB 20/kg, the hydrogen consumption cost is RMB 1400, which is 3 times the coal  
consumption for traditional blast furnace steelmaking and is not yet competitive in the market.  
With the increase of energy efficiency of electrolytic hydrogen production and hydrogen  
energy steelmaking and the decrease of equipment cost, when the cost of green hydrogen is  
reduced to RMB 5−8/kg, the energy cost of hydrogen steelmaking is reduced to RMB 500/ton  
of steel, which is equivalent to that of traditional blast furnace steelmaking. Considering the cost  
of carbon and pollutant emissions, the comprehensive cost-effective advantage of hydrogen  
steelmaking is more obvious. Hydrogen steelmaking is expected to replace traditional blast  
furnace steelmaking in part by 2060 to achieve carbon reduction in the steel industry.  
2.3.2.6 Hydrogen Heating and Electric Heating  
The supply of thermal energy is still mainly dependent on fossil fuels, and 95% of thermal  
energy in the industrial high-quality thermal field is supplied by coal, oil or natural gas. The  
heating price of fossil fuels is low, but the carbon emissions are high. Green hydrogen heating  
or zero-carbon electric heating are both feasible alternatives.  
Both hydrogen heating and electric heating can achieve zero-carbon heating, and since green  
hydrogen is actually a kind of “tertiary energy”, compared with electricity-heat conversion,  
electricity-hydrogen-heat conversion does not have an advantage in energy exchange  
efficiency. In low-temperature heating scenarios such as building heating, hydrogen heating  
has obvious disadvantages in efficiency, and considering factors such as civil safety, pure  
hydrogen heating is not suitable for building energy use. Blending combustion with natural gas  
in existing facilities (10%−15%) can be used as a transitional measure for carbon reduction in  
areas with a good natural gas pipeline foundation. In the field of industrial high-quality heat  
(such as cement, ceramics and glass production), hydrogen heating technology and electric  
095  
The Development and Outlook of Green Hydrogen  
heating technology are close in efficiency and energy cost. In the case that large-scale  
process equipment such as cement kilns are difficult to be directly electrified, hydrogen boilers  
and hydrogen kilns are optional decarbonization technical means.  
In terms of heating efficiency, the thermal efficiency of coal-fired boilers is generally 70%−85%.  
The thermal efficiency of industrial hydrogen-fired boilers can generally reach 90%.  
Considering the whole process of electricity-hydrogen-heat, the energy efficiency will be  
around 60%−80%. There are two technical routes for electric heating: first, electricity is  
converted into thermal energy in circuits and electric heating appliances, and second,  
electricity drives a heat pump to carry thermal energy. The second type of electric heating  
technology, such as heat pumps, makes the heat flow from the low heat source to the high heat  
source by reverse circulation, and only consumes a small amount of reverse circulation net  
power to get a larger heat supply, so the COP is extremely high (up to 200%−400%), but it is  
only suitable for building heat and heating at a lower temperature in industry. The first type of  
electric heating technology, such as resistance heating, electric arc heating, induction heating,  
microwave heating, etc., can be used in a wide temperature range, and can provide high  
temperatures above 1500℃, with an efficiency ranging from 50% to 90%.  
In terms of energy cost and carbon emission, the heating price of fossil fuels is low. With the  
reduction of the power generation cost of renewable energy such as wind and solar, the  
cost-effectiveness of electric heating and green hydrogen heating will be continuously  
improved. Due to the extremely high efficiency of the heat pump technology, the electric heat  
pump technology will have strong economic competitiveness in the fields of building heat, etc.  
In the field of industrial high-quality heat, the energy cost of hydrogen heating is equivalent to  
that of electric heating, and it is expected to become the most cost-effective heating  
technology solution under a certain carbon price.  
The comparison of hydrogen heating, electric heating and coal heating in terms of efficiency,  
energy cost and carbon emission is shown in Figure 2.43.  
Figure 2.43 Comparison Results of Hydrogen, Electric and Coal Heating  
Note: coal heating is calculated as mixed coal of RMB 900/t and 5500 kcal/t; heat pump technology is  
considered for electric heating of building heat, electric boiler technology is considered for electric heating of  
industrial high-quality heat; the electricity used for hydrogen production and heating is zero-carbon electricity,  
and the cost is calculated as RMB 0.3/kWh.  
096  
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Key Technologies for Green Hydrogen  
2.3.3 R&D Direction  
2.3.3.1 Fuel Cell Technology  
A fuel cell is an important way to utilize hydrogen energy efficiently and cleanly. The working  
mechanisms, principles and application scenarios of different types of fuel cells are different,  
but they are generally developed towards high power density, long life, low cost, high reliability,  
etc. There is still great room for improvement in the design and manufacture of key materials  
such as electrocatalysts, proton exchange membranes and membrane electrodes.  
The main focuses include: in terms of membrane materials, improving the proton conductivity  
of proton exchange membranes, improving mechanical strength and thermal stability, and  
improving the preparation process to reduce manufacturing costs; in terms of electrocatalysts,  
improving the catalytic performance and service life of catalysts, while reducing the amount of  
precious metals or developing inexpensive and efficient non-precious metal catalysts,  
optimizing the structure design of gas diffusion electrodes, etc.; in terms of fuel cell systems,  
optimizing auxiliary equipment, strengthening thermal management and material flow  
management of fuel cell systems, and studying high-density assembly technology of fuel cells.  
2.3.3.2 Technology of Hydrogen Fueled Gas Turbine  
In order to improve the power generation efficiency, and reduce the economic cost and  
pollution of hydrogen fueled gas turbines, theoretical research and practical technology  
upgrading are required.  
In theory, it is necessary to study the combustion mechanism and flame structure. The main  
focuses include: research on the turbulent flame velocity of hydrogen-rich fuel combustion,  
research on combustion flame structure of hydrogen fueled gas turbines, design and  
manufacture of hydrogen fuel injectors, and research on the general basic technology of  
closed thermal cycle.  
In practical applications, the effects of hydrogen fuel on combustion systems, compressors  
and turbines need to be considered. It mainly includes adaptation and upgrading of dry  
low-nitrogen burners in heavy gas turbines, research on the impacts of hydrogen on turbines  
and compressors and modification of related equipment. When the conventional gas turbine  
burns hydrogen instead, on the premise of keeping the initial temperature of the gas turbine  
constant, the mass flow rate and volumetric flow rate of fuel will increase to a certain extent,  
which will cause the compressor to surge. Therefore, the matching of the gas turbine with the  
working medium flow of the compressor must be considered in the modification design.  
2.3.3.3 Technologies Related to Green Hydrogen Chemical  
Technologies related to green hydrogen chemical are relatively mature, and will be widely  
applied with the improvement of green hydrogen cost-effectiveness. The main R&D directions  
are: in terms of ammonia synthesis, optimizing the integration and coordination of the two  
systems of water electrolysis and Haber process reactor; in terms of methanol synthesis, an  
efficient, stable and highly selective carbon dioxide methanolization reaction catalyst is  
097  
The Development and Outlook of Green Hydrogen  
developed, and the overall conversion rate of the reaction is improved by improving the  
methanolization auxiliary equipment to recycle fuel gas for multiple times, while increasing the  
recycling of residual heat of the reaction; in terms of synthetic methane, the integration and  
coordination of the two systems of water electrolysis and methanation are optimized, the heat  
management of the methanation process is strengthened, and the recycling of reaction  
residual heat is increased.  
2.3.3.4 Technologies Related to Hydrogen Transportation  
1. Fuel cell vehicle  
FCV is an important technical scheme to realize zero pollution and zero carbon emission. The  
development strategy of FCVs in China is to give priority to the development of commercial  
vehicles, reduce the cost of fuel cells and hydrogen on a large scale through the development  
of commercial vehicles, drive the construction of supporting facilities for hydrogen refueling  
stations (HRS), and finally spread to the passenger car field. Improving the core technology  
level, reducing costs and strengthening infrastructure construction will be the development  
focus in this field.  
The R&D directions include: hydrogen fuel cell related technologies to increase power density,  
extend service life, reduce costs, and improve low-temperature start-up performance of fuel  
cell systems; on-board hydrogen storage technology to strengthen the R&D of high-pressure  
gaseous hydrogen storage tanks, hydrogen storage materials, etc., and to improve hydrogen  
storage density and hydrogen storage mass fraction; FCV vehicle integration technology, etc.  
2. Hydrogen refueling station  
The construction of HRS pursues lower construction cost, smaller construction area, and higher  
safety. At present, the construction cost of HRS in China is high, and the core components of  
equipment such as hydrogen compressors, high-pressure hydrogen storage devices, and  
hydrogen dispensers are all dependent on imports. In order to realize the popularization of  
HRS, it is necessary to accumulate experience in key technologies such as hydrogen  
compression, hydrogen filling and safety monitoring, pay attention to the risk assessment of  
hydrogen refueling stations, and minimize the risk of HRS construction.  
The key technical research directions related to HRS include: R&D of key process equipment  
of HRS, optimization, upgrading and independent production of core equipment such as  
hydrogen compressors, hydrogen dispensers and fixed hydrogen storage facilities; key  
technologies of hydrogen storage, such as 70MPa high-pressure hydrogen storage technology,  
gas hydrogen storage tank technology, localization of key equipment for liquid hydrogen  
storage and transportation, etc.  
3. Hydrogen aircraft  
The core of hydrogen energy aviation technology is a hydrogen fuel propulsion system,  
including two technical schemes: hydrogen turbine and hydrogen fuel cell.  
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Key Technologies for Green Hydrogen  
In the future, in the design scheme with hydrogen turbines as the power of the propulsion  
system, the structure and materials of the turbines need to be modified in order to adapt to the  
changes in the composition of the combustion gas. In order to avoid NOx generated by local  
high temperature in the combustion chamber, firstly, it is necessary to improve or redesign the  
combustion chamber, fuel injection and mixing device, thermal cycle and management system  
of traditional aero-engines; second, it is necessary to develop low NOx emission technologies  
for hydrogen-fueled engines, such as lean direct injection and micro-mixing combustors.  
At present, the energy density of hydrogen fuel cells is only half that of turbine engines, with  
short service life and low output power of single units. In the future, it is necessary to further  
improve the power density of fuel cells and extend their life by adopting the methods of  
integrated structure design, efficient hydrothermal management and operation control.  
4. Hydrogen ships  
The research and application of fuel cells as the ship power system started in the 1990s. With  
the continuous development of hydrogen storage technology and fuel cell technology,  
hydrogen energy has shown great application potential in the field of marine engineering.  
However, hydrogen energy and fuel cells have special application scenarios on ships, and  
further research is needed to promote their applications.  
In terms of fuel cells, the electrical power required by ships is much greater than that of the  
single fuel cells used in vehicle systems to integrate high-power battery stacks. Therefore, it is  
necessary to improve the consistency of single cells and solve the heat dissipation of  
high-power battery stacks. In addition, the ship is in high salt fog corrosion and humid marine  
environment, and corrosion, vibration, impact and other factors will cause damage and  
reliability reduction of the fuel cell stack. Therefore, it is necessary to study the adaptability of  
fuel cells in marine applications and improve the dynamic response speed of fuel cells under  
emergency conditions.  
2.3.3.5 Pure Hydrogen Steel Smelting Technology  
At present, the hydrogen-rich steel smelting technology based on the gas-based direct  
reduction technology of iron is relatively mature and has been put into the commercial  
demonstration stage, and the pure hydrogen steel smelting technology is still in the initial stage  
of R&D.  
The main research directions include: strengthening the research on reaction mechanism in  
the furnace and changes in furnace material characteristics, developing reaction control  
technology for hydrogen reduction of iron ore and improving hydrogen utilization; optimizing  
the structure design of hydrogen shaft furnace and expanding the capacity of shaft furnace;  
developing multi-stage fluidized bed furnaces, improving the primary utilization rate of  
hydrogen in fluidized bed furnaces and the metallization rate of products, and improving the  
operation level of fluidized bed furnaces; studying hydrogen-resistant and high-temperature  
furnace materials and strengthening safety management such as hydrogen explosion-proof  
and leakage-proof.  
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The Development and Outlook of Green Hydrogen  
2.3.3.6 Hydrogen Heating Technology  
The design of hydrogen-fired boilers focuses on improving the safe and explosion-proof  
performance, including the structure design of the boiler body and the safe operation control  
system. The safety of hydrogen boilers must meet the requirements of both hydrogen safety  
and boiler safety at the same time.  
The main research directions include: optimizing the structure design of the boiler body to  
ensure that there are no dead corners in the flue gas process and avoid the accumulation of  
unburned hydrogen; adopting multiple interlocking alarm devices, hydrogen pipes, valves, etc.  
to realize automatic leak detection to ensure safe and reliable operation of the boiler;  
optimizing boiler materials and adopting coatings to avoid hydrogen embrittlement.  
2.3.4 Technical and Economic Trends  
Deep decarbonization is the fundamental driving force to accelerate the application of green  
hydrogen. On the energy consumption side, hydrogen will be mainly used in fields that are  
difficult to be directly electrified, such as chemical, metallurgical and aviation, etc., to realize  
indirect power replacement; on the energy production side, hydrogen power generation is an  
important long-term regulation and supportive power supply for a high proportion of new  
energy power systems.  
Green hydrogen is mainly used for ammonia synthesis, methanol, methane and other fuels or  
raw materials in the chemical field, replacing grey hydrogen in traditional processes. The  
green hydrogen technology is relatively mature, and the extent of promotion depends mainly  
on the carbon constraints policy and the cost-effectiveness of green hydrogen. It is expected  
that by 2030, ammonia production from green hydrogen will take the lead in the commercial  
promotion, with the cost reduced to RMB 2.9/kg, which is equivalent to the current cost of  
ammonia synthesis from fossil fuels; the demonstration application of methanol production from  
green hydrogen will be achieved, with the cost reduced to RMB 3.5/kg, which is close to the  
current cost of methanol production from fossil fuels (including carbon capture); the cost of  
synthetic methane from green hydrogen will be reduced to about RMB 5/m3 with demonstration  
applications started in some end users. It is expected that by 2050, the cost of ammonia  
production from green hydrogen will be reduced to RMB 2.4/kg, making it the most  
cost-effective ammonia synthesis mode; the methanol production from green hydrogen will be  
put into commercial use, with the cost reduced to less than RMB 2/kg, equivalent to the cost of  
methanol production from coal; the cost of synthetic methane from green hydrogen will be  
reduced to about RMB 2.4/m3, widely used by energy end-users far away from natural gas  
production.  
Green hydrogen can be used for ironmaking in the metallurgical industry and combined with  
electric furnace steelmaking to achieve zero carbon emission in the steelmaking process. It is  
expected that by 2030, the hydrogen shaft furnace structure will be further improved and the  
hydrogen utilization rate will be improved. With the decrease of green hydrogen cost, the  
hydrogen consumption cost of green hydrogen ironmaking will be reduced to RMB 950/ton,  
which is equivalent to the cost-effectiveness of blast furnace ironmaking and is ready for  
commercial promotion; by 2050, with the further decline in green hydrogen cost and the  
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Key Technologies for Green Hydrogen  
accumulation of experience in special furnace body equipment management, the hydrogen  
consumption cost of green hydrogen ironmaking will be further reduced to RMB 500/ton, and  
the cost-effective advantage will be gradually highlighted.  
The application of green hydrogen in the transportation field mainly includes scenarios where it  
is difficult to achieve direct electrification such as public transits, heavy trucks, ships, and  
airplanes. Compared with electric vehicles, hydrogen-powered vehicles have certain  
advantages in terms of load and endurance, and are expected to be popularized in public  
transits, heavy trucks, forklifts and other fields. By 2050, the replacement rate of hydrogen fuel  
cell vehicles in public transits, heavy trucks, forklifts and other fields will reach about 30%, and  
the replacement rate in small and medium-sized passenger cars will be about 5%. For  
navigation, aviation and other fields, using green hydrogen as fuel is an important  
decarbonization scheme.  
Green hydrogen is applied based on two technical routes of fuel cells and hydrogen fueled  
gas turbines in the power generation field to provide long-term flexibility. By around 2035, the  
pure hydrogen fueled gas turbine technology is expected to be mature, and the hydrogen  
fueled gas turbine power generation is expected to be put into commercial use. By 2050, the  
cost of hydrogen fueled gas turbine will be reduced to about RMB 2000/kW, and the cost of  
power generation system including auxiliary equipment and other facilities will be RMB  
3000/kW, with a generation efficiency of 40%−45%, which is mainly used as the supporting  
power for large peakload units and load centers. the cost of the hydrogen fuel cell will be  
reduced to RMB 800−1000/kW, the cost of hydrogen fuel cell generation system will be RMB  
1500−2000/kW, and the generation efficiency of fuel cell power station will be increased to  
55%−60%, which will be widely used in distributed application scenarios. Hydrogen power  
generation with green hydrogen as fuel is essentially equivalent to large-scale and long-term  
energy storage of the system, realizing the inter-seasonal balance of power supply and  
demand, and is an indispensable source of flexibility for new power systems with new energy  
as the main body.  
2.4 Summary  
The key to the development of green hydrogen is to realize the cost-effective and zero-carbon  
preparation of hydrogen, convenient and efficient storage and transportation, and safe and  
effective utilization.  
In terms of hydrogen production technology, the use of renewable energy to produce green  
hydrogen by water electrolysis will become the dominant hydrogen production method. It is  
estimated that by 2030, the high-efficiency and high-power alkaline electrolysis technology and  
low-cost proton exchange membrane electrolysis technology will make a breakthrough, the  
efficiency of electrolytic hydrogen production will rise to about 80%, the cost of the hydrogen  
production system will be reduced to RMB 3000/kW, and the cost of green hydrogen will be  
reduced to RMB 15−20/kg. Compared with blue hydrogen, it shows initial cost-effectiveness  
and commercial promotion will be started; By 2050, the high-efficiency, long-life and  
high-temperature solid oxide electrolysis technology will make a breakthrough, the electrolytic  
hydrogen production efficiency will be increased to about 90%, the cost of hydrogen  
production system will be decreased to RMB 2000/kW, and the cost of green hydrogen will be  
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The Development and Outlook of Green Hydrogen  
decreased to RMB 7−11/kg, making it the mainstream hydrogen production mode.  
In terms of hydrogen storage technology, gaseous hydrogen storage and liquid hydrogen  
storage technologies are relatively mature, and material-based hydrogen storage needs to be  
broken through. Large-scale fixed hydrogen storage is expected to be in the form of  
high-pressure gaseous hydrogen storage with a storage pressure of 15−50MPa, and the  
current construction cost of hydrogen storage equipment is about RMB 1000/kg hydrogen. By  
2030, the carbon fiber wound high-pressure hydrogen cylinder manufacturing technology is  
expected to be further mature, and the cost of hydrogen storage equipment is expected to  
decrease to RMB 500−800/kg hydrogen. By 2050 and 2060, it is expected to further decrease  
to about RMB 300/kg and RMB 250/kg. For small-scale hydrogen storage, full composite light  
fiber wound storage tanks will be used, with the pressure of 35MPa or 70MPa. By 2030, the  
technology of full composite light fiber wound storage tank at 70MPa is expected to be mature,  
and the cost is expected to decrease to RMB 3500/kg. By 2050 and 2060, it is expected to  
further decrease to RMB 2000/kg and RMB 1500/kg.  
In terms of hydrogen transportation technology, different hydrogen transportation modes are  
applicable in different scenarios. In small and medium-scale scenarios, gaseous hydrogen  
tank trucks are mainly used for short-distance transportation (<300km), and the unit hydrogen  
transportation cost is RMB 3−6/kg. The liquid hydrogen tank trucks are mainly used for  
medium-distance transportation (300−100km), and the unit hydrogen transportation cost is  
RMB 5−10/kg. In large-scale scenarios, the combination of the replacing hydrogen  
transportation with power transmission with hydrogen transportation through pipelines will be  
used. At present, the investment cost of hydrogen transportation pipeline is about 1.5 times  
that of the natural gas pipeline (considering the annual transportation capacity of 12 billion m3,  
it is about RMB 20.2 million/km). It is expected that by 2030, the pure hydrogen pipeline  
manufacturing technology and the pressure reduction and pressure regulation technology are  
expected to be mature, and the construction cost of large-scale hydrogen transportation  
pipelines is expected to decrease to RMB 13.5 million/km, equivalent to the current cost of  
natural gas pipelines. The transportation loss (including gas loss and energy consumption) per  
1000km of hydrogen transportation pipelines will be controlled at about 1%, and the unit  
hydrogen transportation cost will be controlled at RMB 2.7/kg. By 2050, new hydrogen  
transportation pipelines made of fiber-reinforced polymer composites and others are expected  
to be put into commercial use, the transportation loss per 1000km of hydrogen transportation  
pipelines will be controlled at 0.3%−0.5%, and the unit hydrogen transportation cost will be  
controlled at about RMB 2/kg. By 2060, with the further maturity of hydrogen transportation  
pipeline technology, the transportation loss per 1000km of hydrogen transportation pipelines is  
expected to further decrease to 0.1%−0.2%, reaching the current level of natural gas pipelines,  
and the unit hydrogen transportation cost will be below RMB 2/kg.  
In terms of hydrogen utilization technology, hydrogen is mostly used in the chemical field at  
present and mainly grey hydrogen. In the future, it is necessary to focus on the development of  
green hydrogen application potential in the fields of industry, transportation and power  
generation. In the construction field, due to the constraints of safety, efficiency, and cost, the  
future application potential is small. By 2030, the fuel cell technology is expected to be  
basically mature, and green hydrogen heavy trucks and buses and distributed hydrogen  
power generation will be gradually promoted and applied. The green hydrogen ironmaking  
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Key Technologies for Green Hydrogen  
technology will be gradually improved and ready for commercial promotion. With the decrease  
of green hydrogen cost, ammonia production from green hydrogen will have economic  
advantages, and methanol and methane production from green hydrogen will have  
demonstration conditions. By around 2035, the pure hydrogen fueled gas turbine technology is  
expected to be mature, and the hydrogen fueled gas turbine power generation is expected to  
be put into commercial use. By 2050, the technologies of power to fuels and raw materials such  
as green hydrogen to methanol and methane are expected to be mature and have economic  
advantages.  
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Green Hydrogen Demand Projection and Development Potential  
Green Hydrogen  
Demand Projection  
and Development  
Potential  
The Development and Outlook of Green Hydrogen  
The demand for green hydrogen determines the size of green hydrogen industry,  
and the development potential and cost of green hydrogen determine the upper  
limit and economic benefits of green hydrogen development. What is the  
demand for green hydrogen, how much development potential is there, and  
where low-cost green hydrogen is distributed are the required questions for  
hydrogen energy development under the background of carbon neutrality and  
energy transition. In this chapter, starting from the economic and social  
development and the transition of energy system, combined with the energy  
demand of various industries, the demand for raw materials and the development  
trend of hydrogen utilization technology, the future demand for green hydrogen in  
China is predicted. Based on GEIDCO’s research results in the fields of clean  
energy power generation technology and global clean resource assessment,  
and relying on the GREAN, quantitative assessment is made on the development  
potential and cost distribution of green hydrogen in China.  
3.1 Demand Forecast  
3.1.1 Economic and Social Development Expectation  
3.1.1.1 Economic Development  
1. Development status  
Since the reform and opening up, China has maintained rapid growth in its economy, with  
remarkable achievements in urbanization and industrialization. Its GDP has grown at an  
average annual rate of 9.2%, much higher than the world economy’s average growth rate of  
2.7% in the same period. In 2020, China’s overall economic performance was stable with a  
continuously optimized economic structure, and the First Centenary Goal of building a  
moderately prosperous society in all respects was successfully achieved despite the impact of  
the COVID-19 epidemic. Guided by the new vision on development, China will steadily shift to  
a stage of high-quality development, embark on a new journey to a socialist modernized  
country in an all-round way, and work hard toward the Second Centenary Goal.  
Sustained and rapid economic development shows strong resilience and great vitality. In 2019,  
China’s GDP is RMB 99.1 trillion, up 6.1% year on year, contributing about 30% to world  
economic growth. In 2020, China’s GDP amounted to RMB 101.6 trillion, up 2.3% year on year,  
making it the only major economy in the world with positive economic growth despite the  
impact of the COVID-19 epidemic. Translated at the average annual exchange rate, China’s  
economic aggregate accounted for more than 17% of the world’s total. China’s GDP and  
growth rate from 2000 to 2020 are shown in Figure 3.1.  
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Green Hydrogen Demand Projection and Development Potential  
Figure 3.1 China’s GDP and Growth Rate from 2000 to 2020  
The industrial structure is improved and adjusted to be more coordinated and balanced.  
Since the 18th CPC National Congress, China has strengthened the basic role of agriculture  
and rapidly promoted the leading role of industry, with the increasingly prominent supporting  
effect of the service industry on the economy and society, and the more balanced development  
speed of the three industries. In 2020, the proportion of primary, secondary and tertiary  
industries was 7.7%, 37.8% and 54.5%, respectively. The change in the proportion of the added  
value of three industries in China from 2000 to 2020 is shown in Figure 3.2.  
Figure 3.2 Change in Proportion of Added Value of Three  
Industries in China from 2000 to 2020  
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The Development and Outlook of Green Hydrogen  
Industrial production capacity is growing and gradually moving to the medium-high level. At  
present, China is the world’s only country with all the industrial categories listed in the  
Industrial Classification Standard Industrial Classification of United Nations, and the output  
of more than 200 industrial products ranks first in the world. China has become the world’s  
largest manufacturer for 11 consecutive years as its industrial added value amounted to  
RMB 31.3 trillion in 2020, In 2020, the added value of high-tech manufacturing and  
equipment manufacturing accounted for 15.1% and 33.7% of the added value of industrial  
enterprises above the designated size, respectively. During the 13th Five-Year Plan period,  
the average growth rate of these two types of manufacturing industries reached 10.4%,  
which was 4.9 percentage points higher than that of industrial enterprises above  
designated size, and became the main force driving the development of the manufacturing  
industry.  
The service industry has entered a phase of fast development. From 2016 to 2019, the  
contribution rate of Chinese tertiary industry to GDP growth exceeded 60% and increased year  
by year. Although the contribution of the tertiary sector to GDP growth slightly declined in 2020  
under the impact of the COVID-19 epidemic, new industries and new business forms kept  
growing against the trend, the operating revenue of strategic emerging service companies  
grew by 8.3% year on year, 6.4% faster than the growth rate of service industries above overall  
size. Online retail, online education, telecommuting and other online services are in strong  
demand, and information transmission, software and information technology services grew by  
16.9%.  
The level of openness continues to improve. Since the reform and opening up, China has  
achieved trans-regional development in foreign trade and economic cooperation. From 1978 to  
2019, the total export-import volume of goods increased by 222 times at an average annual  
rate of 14.1%, 7.3% higher than that of global trade in goods during the same period. Foreign  
investment in actual use continued to grow, with its share in the global market rising to 9.2% in  
2019. In 2020, China took the initiative to strengthen international cooperation in fighting the  
epidemic and actively participated in economic globalization, and the total export-import  
volume of goods increased by 1.9% and 4.0% respectively year on year, both hitting record  
highs, making China remain the largest country in global trade in goods. China achieved a  
foreign direct investment of USD 163 billion, making it the world’s largest destination for foreign  
investment for the first time.  
Fruitful results have been achieved in making China an innovative country. China has greatly  
enhanced its scientific and technological strength and innovation capacity since the reform  
and opening up, and further achieved historical and global changes since the 13th Five-Year  
Plan, with social investment in R&D growing from RMB 1.4 trillion in 2015 to about RMB 2.4  
trillion in 2020 at a rate of 2.4%. It has also achieved a large number of major achievements in  
manned spaceflight, lunar exploration programs, deep-sea engineering, supercomputing,  
quantum information, UHV power transmission, CR high-speed trains, giant aircraft  
manufacturing and other fields. In 2020, China ranked 14th in the Global Innovation Index  
released by the World Intellectual Property Organization (WIPO), showing its leading  
advantages in many fields, and was the only middle-income economy among the top 30 in  
comprehensive ranking.  
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Green Hydrogen Demand Projection and Development Potential  
2. Development prospect  
China has shifted to a stage of high-quality development, with its economy in long-term steady  
growth. As the current GDP per capita in China exceeds USD 10,000, China’s economy has  
shown strong development momentum, its economic structure continues to be optimized, and  
its economy has shifted to a new high-quality development stage under the leadership of the  
new development concept.  
From 2020 to 2030, China will accelerate the revolution in quality, efficiency and motive power  
of economic growth. On the supply side, with the deepening of market-oriented factor  
allocation reform and the continuous improvement of scientific and technological innovation in  
China, economic growth will further shift from factor-driven growth to innovation-driven growth,  
and the improvement of total factor productivity will become a key contributing factor to  
economic growth. On the demand side, the construction of a new pattern of development  
featuring domestic circulation as the mainstay and mutually reinforcing domestic and  
international cycles will be accelerated. The potential of domestic demand will be further  
unleashed, and consumption will play a more fundamental role in economic development and  
become the primary driving force for economic growth. As the overall growth of investment in  
fixed assets gradually slows down, the room for investment in fields with excess capacity such  
as traditional infrastructure, iron and steel, cement and nonferrous metals will gradually  
saturated. Key fields of investment include new infrastructures such as UHV grids, 5G,  
Industrial Internet and big data center. In terms of industrial structure, the proportion of tertiary  
industry in the national economy and its contribution to economic growth are gradually  
increasing, the production-oriented service industries are becoming more specialized and  
high-end in the value chain, and the consumer-oriented service industries are becoming  
high-quality and diversified. The secondary industry maintains a complete range and industrial  
system, with a steady decline in its proportion and continuous optimization and upgrading of  
its internal structure. Traditional manufacturing industries will shift to high-end, intelligent  
and green industries. High-tech manufacturing and strategic emerging industries, such as  
NGIT, renewable energy, new materials, high-end equipment and NEVs, will maintain rapid  
growth and become a new driver for the development of the secondary industry. As its GDP  
gross is expected to reach RMB 169 trillion in 2030 at an average annual growth rate of 5.2%  
from 2020 to 2030, with added values of the three industries accounting for 5.9%, 37% and  
57.1%, China is likely to become the largest economy in the world according to the market  
exchange rate.  
From 2030 to 2050, a modernized economy will be built in China. With the continuous rise of its  
total factor productivity, China will maintain a stable and sustainable economic growth and  
lead the world in economic scale. China will lead the world in a large number of strategic  
emerging industries, including NGIT, renewable energy, and the digital economy field. A new  
type of infrastructure system is in place to form a large-scale and networked layout for  
intelligent digital infrastructure such as modern energy, data centers, intelligent transport  
system and Industrial Internet. China will become a leading innovation-oriented country in the  
world by building on its own core technologies. In terms of industrial development, a  
development pattern driven by both the advanced manufacturing industry and the modern  
service industry is formed to promote “Made in China” and “China Services” simultaneously.  
The service industry plays a dominant role in the industrial structure, and the manufacturing  
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The Development and Outlook of Green Hydrogen  
industry has become high-end and environmentally friendly. The tertiary industry will play a  
dominant role in China’s economy, absorbing more than 70% of the employed population and  
becoming the main sector contributing to economic growth. The scale of service trade  
continues to expand, and the share of knowledge-intensive service exports continues to rise.  
High-end service industries such as digital services, information and communications, modern  
finance, and cultural and creative industries rank the world’s first tier in terms of scale and  
competitiveness. The traditional manufacturing industry has become more high-end,  
environmentally friendly and intelligent. A number of advanced manufacturing clusters have  
been formed in new energy, new materials, NEVs, and high-end equipment. Service-oriented  
manufacturing has grown in scale, and China has become a manufacturing power. From  
2030 to 2050, China’s GDP is expected to grow at an average annual rate of about 3.5%.  
By 2035, China will double its economic aggregate and per capita income over those in  
2020 and basically deliver the goal of socialist modernization. China’s real GDP will reach  
RMB 338 trillion by 2050, with added values of the three industries accounting for 4.2%,  
32.6% and 63.2%, and China will develop itself into a great modern socialist country that is  
prosperous, strong, democratic, culturally advanced, harmonious and beautiful, achieve  
prosperity for all, and keep its income per capita at the top of middle-income developed  
countries.  
From 2050 to 2060, China’s economy will continue to grow steadily and play a leading role in  
global economic development. The enhanced deep integration of the digital economy and the  
real economy has empowered industrial production, social life and public management, further  
enhancing the efficiency of economic development, creating a large number of new business  
models and new models, and leading the world in the platform economy, sharing economy and  
green economy. By building the world’s leading high-level open economy, and fully realizing a  
large-scale, wide-range and deep-level open development pattern, it has become an important  
engine and stabilizer for global development. China’s world-leading digital service industry  
continues to consolidate its position as a manufacturing power. A number of high-end  
service industry center cities with global impacts and “Chinese Service” brands will dominate  
and lead the global value chain. On the basis of building a manufacturing power, we will  
complete the transformation and upgrading of intelligent manufacturing in an all-round way.  
New business forms and models of digitization such as intelligent manufacturing and  
industrial internet have grown mature, leading to the formulation of international rules and  
standards in the fields of high-end manufacturing, digital industry and clean production.  
China’s real GDP is expected to reach RMB 435 trillion in 2060 at an average annual growth  
rate of about 2.5% from 2050 to 2060, with added values of the three industries accounting  
for 3.6%, 30.5% and 65.9%. The projection of China’s economic growth from 2020 to 2060 is  
shown in Table 3.1, and the three projections of China’s industrial structure from 2020 to 2060  
are shown in Figure 3.3.  
Table 3.1 Projection of China’s Economic Growth from 2020 to 2060  
Item  
2020—2030  
2030—2040  
2040—2050  
2050—2060  
Average GDP growth rate (%)  
5.2  
4.0  
3.0  
2.5  
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Green Hydrogen Demand Projection and Development Potential  
Figure 3.3 Three Projections of China’s Industrial Structure from 2020 to 2060  
3.1.1.2 Social Development  
1. Development status  
The total population has grown steadily and the working-age population has reached its  
peak. Since the reform and opening up, the total population of the Chinese mainland has grown  
from 960 million to 1.41 billion in 2020A, and the total working-age population aged 15 to 64  
has grown from 630 million in the early 1980s to a peak of 1.01 billion in 2013. The fully  
released demographic dividend and the continuously optimized structure of labor resource  
allocation strongly support the rapid growth of China’s economy. The natural population growth  
slows down, and the aging problem appears. Since the 1990s, the natural population growth  
rate in China has continued to decline. During the 13th Five-Year Plan period, the natural  
population growth rate briefly rose under the influence of the “two-child policy” regulation, but  
then fell back. In 2019, the natural population growth rate of China was 0.334%. There are 254  
million people aged 60 and above, accounting for 18.1% of the total population, and 176  
million people aged 65 and above, accounting for 12.6% of the total population, and the total  
dependency ratio is 41.5%, so China is in the early stage of aging. The human capital dividend  
has gradually replaced the demographic dividend to become an important “driver” for China’s  
economic growth. In 2019, China’s working-age population stood at 989 million, with average  
education years of 10.7. According to the Human Development Report 2020 released by the  
United Nations Development Programme, China ranks 115th in the world in terms of average  
years of education, significantly lower than the ranking in the Human Development IndexB, and  
AAccording to the results of the 7th National Census, the total population of China is 1,411.78 million,  
including 31 provinces, autonomous regions, municipalities, active soldiers of the People’s Liberation Army,  
Hong Kong and Macao Special Administrative Regions and Taiwan.  
BThe human development index is the main international index to measure the social development level and  
the living standard of the people in the country or region. It is comprehensively measured and calculated  
according to the life expectancy, mean years of schooling and the per capita income. It is divided into four  
groups: Extremely high (0.8 and above), high (0.799 ~ 0.7), medium (0.699 ~ 0.550) and low (0.549 and  
below). In 2020, China’s human development index is 0.761, ranking 85th in the world.  
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The Development and Outlook of Green Hydrogen  
still has great room for improvement. With the continuous improvement of population quality  
and inter-generational replacement, the talent dividend brought by the improvement of education  
level will become an important foundation to drive China’s economic development. Figure 3.4  
shows the total population and natural growth rate of Chinese mainland from 1990 to 2019.  
Figure 3.4 Total Population and Natural Growth Rate of Chinese Mainland from 1990 to 2019  
The process of urbanization has been accelerated with the level of urbanization significantly  
improved. Since the reform and opening up, the urban population has increased rapidly. In  
2019, China’s permanent urban population stood at 850 million, an increase of 680 million from  
the end of 1978, and the urbanization rate of the permanent population reached 60.6%, which  
was slightly higher than the world average of 55.3% but significantly lower than 81.3% of  
high-income economies and 65.2% of middle- and high-income economies. There is still huge  
room for growth in the urbanization rate in the future. Urban agglomerations are significantly  
distributed in all directions, and small, medium, and large cities develop in a coordinated and  
balanced manner. In 2019, China’s 19 urban agglomerations gathered 75% of the country’s  
population in 25% proportion of the national land area, creating 88% of GDP. The mega-urban  
agglomerations represented by Beijing—Tianjin—Hebei, Yangtze River Delta and Pearl River  
Delta urban agglomerations, the central urban agglomerations represented by Changsha—  
Zhuzhou—Xiangtan and Central Henan urban agglomerations and the western urban  
agglomerations represented by Chengdu—Chongqing and Kuan—chung Plain urban  
agglomerations constitute an important foundation and driving force for China’s economic  
development. Small and medium-sized cities continue to integrate the space, resources, labor  
and other comparative advantages, promote the development of special industries according  
to local conditions, and form a closely linked industrial division of labor system with large cities.  
The comprehensive strength of cities and the degree of globalization have been continuously  
enhanced. Six Chinese cities are ranked in the Alpha level and 13 in the Beta level in the List of  
A
World Cities and Urban Area 2020  
according to GaWC. The trend of permanent population  
AGlobalization and World Cities Research Network (GaWC) is one of the world’s most famous think tanks and  
city rating agencies. Since 2000, the Roster of World Cities has been issued irregularly to quantify the  
global connectivity of world cities in five sectors: Finance (banking, insurance), advertising, law,  
accounting and management consulting. GaWC divides the city into four categories: Alpha, Beta, Gamma  
and Sufficiency (+/-) (i.e. the world’s first, second, third and fourth tiers) to measure the city’s position in the  
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and urbanization rate in urban and rural areas of China from 2000 to 2019 is shown in  
Figure 3.5.  
Figure 3.5 Trend of Urban and Rural Population and  
Urbanization Rate in China from 2000 to 2019  
The income per capita has increased substantially, and the people lead a moderately  
prosperous life in all respects. In 2020, China’s gross national income per capita exceeded  
USD 10,000 for the second consecutive year, ranking firmly among the upper-middle-income  
countries, and the goal of doubling the per capita income of urban and rural residents in 2010  
was achieved as scheduled. With the complete victory of the fight against poverty, all the 98.99  
million rural poor living below the current poverty line were raised from poverty, as were all the  
832 counties and 128,000 villages classified as poor. Overall regional poverty no longer exists,  
and the arduous task of eliminating absolute poverty is accomplished. The middle-income  
group continues to expand and is playing an increasingly important role in economic  
development. At present, China’s middle-income group has reached 400 million people,  
accounting for about 30% of the total population, but there is still a certain gap with the  
developed countries such as Europe and America where the population of the middle-income  
group accounts for more than 60% of the total population A. The expansion of the  
middle-income group will actively promote the internal impetus of China’s economic growth  
from investment to consumption.  
The system of basic public services has been improved, and the level of equality has been  
steadily improved. The construction of a multi-tiered social security system has been  
accelerated, and the number of people covered by old-age insurance, medical insurance,  
unemployment insurance, work-related injury insurance, and maternity insurance has  
continued to increase. As of the end of 2020, the all-inclusive number of people participating in  
basic medical insurance is 1.36 billion, with a coverage rate of over 95%, and the world’s  
global high-end production and service network and its integration.  
AAccording to the current statistical standards, the middle-income group refers to the group in the Family of  
three with annual income of RMB 100,000 to RMB 500,000.  
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largest social security system has been established. The modernization of education has made  
positive progress, and the consolidation rate of nine-year compulsory education has reached  
95.2%. The medical service system is improving day by day, and the average life expectancy  
of residents is 77.3 years, which is nearly 5 years higher than the world average life expectancy.  
The universal power access has achieved leapfrog development. In 2015, the problem of  
power consumption for population with no access to electricity was fully solved, and the  
access to electricity reached 100%.  
2. Development prospect  
China’s population development will enter a critical transition period from 2020 to 2030, and  
the inertia of total population growth will weaken. As the United Nations (UN), the China  
Development Research Foundation (CDRF), the Chinese Academy of Social Sciences (CASS)  
and many other institutions predicted, China’s total population will reach its peak around 2030,  
with a labor force aging problem and a declining proportion of children. According to the World  
Population Prospects released by the United Nations in 2019, the total population will be about  
1.458 billion in 2025, about 1.464 billion in 2030. The urbanization rate will further rise, and  
urban agglomerations and metropolitan areas will become important carriers for coordinated  
and distinctive development of small, medium and large cities and small towns. The Outline of  
the 14th Five-Year Plan (2021—2025) for National Economic and Social Development and the  
Long-Range Objectives Through the Year 2035 of the PRC (Draft) proposes to improve the new  
urbanization strategy and promote people-centered new urbanization. With the further  
integration of the rural dwellers into cities in the future, urban agglomerations and metropolitan  
areas will further develop and grow, forming a spatial pattern of urbanization featuring a  
reasonable density, an appropriate division of labor and improved functions. China’s  
urbanization rate is expected to reach about 65% by 2025 and about 68% by 2030, and the  
urban population will reach 1 billion. The forecasts of China’s population development by the  
United Nations, China Development Foundation, Academy of Social Sciences and other  
institutions are shown in Table 3.2.  
Table 3.2 Projections of China’s Population Development by Various Institutions  
Unit: 100 million people  
Organization  
Peak year  
UN (medium-variant) UN (high-variant) UN (low-variant)  
CDRF  
2030  
CASS  
2029  
14.42  
2031  
2044  
2026  
Peak population  
14.64  
15.17  
14.47  
14.2-14.4  
From 2030 to 2050, the education and health quality of the population will continue to improve.  
According to the World Population Prospects (medium-variant projection) released by the  
United Nations in 2019, China’s population will drop to about 1.4 billion by 2050, and the  
population aged 65 or above will reach about 400 million, accounting for nearly 30% of the total.  
At the same time, the level of education will be significantly improved to make up for the  
decrease in the labor force. The average education years for China’s working-age population  
are expected to increase from 11 years in 2020 to 14 years in 2050. The average life  
expectancy will reach 83 years, and there will be more than 850 million people in the  
middle-income group. A highly coordinated development will be achieved between urban and  
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rural areas and among different regions. Urban agglomerations will become the key areas  
for population migration and mobility. It is estimated that an additional 250 million people  
will live in cities by 2050, with an urbanization rate of 80%, and there will be more than 15  
metropolitan areas with a population of 20 million or more. Therefore, the urban spatial  
structure will be further optimized to form a networked urban agglomeration pattern  
featuring multi-center, multi-level and multi-node. The international competitiveness of  
megacities will be further enhanced, and large and medium-sized cities will more suitable  
for people to live and work in. Agriculture and rural areas will be modernized, and rural  
industries with distinctive rural features, such as strong agriculture, beautiful countryside,  
well-off farmers, rural tourism and healthcare, have become important pillars for  
sustainable rural development.  
From 2050 to 2060, the population will slowly decline, and urbanization and rural revitalization  
will reach a new level. China’s population is expected to reach about 1.33 billion by 2060, with  
an urbanization rate further rising to about 83%. The gap in development between urban and  
rural areas and among regions and in people’s living standards will be further narrowed, and  
the middle-income group will be expanded to over 900 million people. The United Nations’  
2019 Revision of World Population Prospects predicts the population of Chinese mainland from  
2020 to 2060 as shown in Figure 3.6.  
Figure 3.6 Population Projection of Chinese Mainland from 2020 to 2060  
3.1.2 Prospect of Energy Scenarios  
Carbon emissions from energy activities are critical to achieving carbon neutrality throughout  
the society, mainly including carbon emissions during energy production and energy use. The  
key to de-carbonization in energy activities is to reduce fossil fuel consumption with clean  
energy-dominant energy supply and electric-centric energy consumption. According to the  
requirements for achieving the carbon neutrality objective and in combination with the selection  
of different technical routes, the report proposes two different energy development scenarios:  
“electricity replacement” and “electricity + hydrogen energy”.  
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3.1.2.1 “Electricity Replacement” Scenario  
In the scenario of “electricity replacement”, energy consumption is transformed to electric-  
centric, and in the final energy consumption field where electricity cannot be directly used,  
fossil energy + carbon capture and storage (CCS) is used to achieve decarbonization. Energy  
production is shifted from fossil fuels-dominant to clean energy-dominant, reducing dependence  
on fossil fuels.  
At the early peaking stage (before 2030), the total fossil fuels consumption will peak by 2030,  
and the proportion of clean energy consumption in primary energy consumption will increase  
from 15.3% at present to more than 30%. The total electricity consumption is increasing year by  
year. In 2030, the electricity consumption of the whole society will reach 10,700 TWh,  
accounting for 33% of the final energy consumption.  
In the rapid mitigation stage (2030—2050), the total consumption of fossil fuels will drop to 1.67  
billion tons of standard coal equivalent in 2050, and the scale of clean energy consumption will  
be accelerated, accounting for 70% of the primary energy by 2050. In 2050, the electricity  
consumption of the whole society will reach 13,300 TWh, and over half of the final energy  
consumptionwill be met by electricity.  
In the overall neutrality stage (2050—2060), based on the construction of China Energy  
Interconnection, the development of clean energy such as hydro, wind and solar power  
willincrease, the total fossil fuel consumption will decrease to 1.04 billion tons of standard coal  
equivalent in 2060, the scale of clean energy consumption will further expand, accounting for  
81% of the primary energy, and the comprehensive transformation of the energy production  
system will be realized. The electricity consumption of the whole society reached 14,000 TWh,  
and the electrification rate reached 55%, realizing the deep electrification transformation on the  
energy consumption side.  
3.1.2.2 “Electricity + Hydrogen Eenergy” Scenario  
In the scenario of “electricity replacement”, where electrification is fully realized in the fields of  
industry, transportation, construction, etc., the problem of carbon emissions still needs to be  
solved in chemical, metallurgy, aviation and other fields that are difficult to use electricity  
directly. If fossil energy + CCS is adopted, it is expected that by 2060, a total of 1040 Mtce  
of coal, oil and natural gas will be used in these areas, and about 1.58 billion tons of carbon  
dioxide will need to be removed. Chemical, metallurgical and other industries have  
complex tail gas components, low carbon dioxide concentration and high cost of capture  
and storage. It is difficult for transportation industries such as aviation and shipping to directly  
capture CO2.  
Under the condition of “electricity + hydrogen energy”, the use of green hydrogen instead of  
fossil fuels to meet the energy consumption in the above-mentioned areas that are difficult to  
achieve direct electrification, can greatly reduce the demand of energy activities for CCS  
during carbon neutrality and achieve more efficient and economical decarbonization.  
Therefore, the chemical, metallurgical, aviation and other industries are the most important  
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application areas of green hydrogen in the future, and it is necessary to focus on the research  
and projection of the application scale.  
3.1.3 Projection Models and Methods  
In order to study the hydrogen demand in different industries in the future, the report  
establishes a projection model for the application scale of green hydrogen in a combination of  
top-down and bottom-up manner.  
There are many energy sectors and various impact factors in the whole society, and the  
technical principles, characteristics and development stages of different categories vary  
significantly. To predict the hydrogen demand of various industries, on the one hand, it is  
necessary to build a top-down quantitative analysis model of the economic, technological and  
policy demand for hydrogen in specific industries; on the other hand, energy consumption data  
and raw material production data in various fields need to be refined from bottom to top to  
support model parameter identification and verification. As the development of hydrogen  
application technology in most fields is still at an early stage, the data related to hydrogen  
application are difficult to be comprehensively counted. In this report, approximate indicators  
such as growth rate, replacement rate and hydrogen conversion rate are mainly used to  
describe the comprehensive action of various factors. Firstly, according to the key segments of  
the future hydrogen energy application, the total energy or raw material demand is  
extrapolated based on the industry historical data, population projection data, GDP projection  
data, etc., then the portion of the future demand that can be met by hydrogen is calculated  
according to the hydrogen replacement rate, and finally the total hydrogen consumption scale  
is calculated according to the hydrogen conversion rate.  
The hydrogen scale projection model is shown in Figure 3.7. Based on the data of population  
projection, economic projection and other factors, considering the policy impacts, the S-type  
Figure 3.7 Schematic Diagram of Hydrogen Demand Projection Model  
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The Development and Outlook of Green Hydrogen  
population simulation model is adopted to simulate, and the energy and non-energy  
demand in the sub-industry scenarios such as chemical, transportation and metallurgy is  
analyzed. Suppose the fitting function of the demand is  
K − A  
1+ exp[−B(t − M )]  
f (t) = A +  
Among them, t is the year, A is the initial demand of a certain total demand of an industry sector,  
K is the final demand, B is the impact factor, and M is the year when the total demand rises  
most rapidly. The numerical setting of each parameter is based on historical data as the  
boundary condition. Considering the development law of the industry sector, the support of the  
policy environment under the vision of carbon neutrality and other factors, it is necessary to  
make a detailed division for different industries.  
At the same time, according to the analysis of the status of hydrogen utilization technology and  
technical cost, the technical maturity model is used to analyze the potential of hydrogen  
replacement and the level of hydrogen utilization technology in the future, and the green  
hydrogen replacement growth model is analyzed by various fitting processes with reference to  
the historical development laws such as the change of electricity replacement. Considering the  
technological progress of the emerging hydrogen industry and the decrease in unit hydrogen  
consumption caused by the increase of technology conversion rate, the unit hydrogen  
consumption of each technology at different time points is calculated, and the scale of  
hydrogen consumption in different fields is obtained in combination with the changes in total  
demand and replacement rate.  
3.1.4 Analysis of Main Hydrogen Fields  
3.1.4.1 Chemical Field  
The scale projection of chemical hydrogen consumption needs a specific analysis of important  
chemical raw materials such as ammonia, methane, methanol, etc., taking into account various  
factors such as demand change of chemical products, the hydrogen consumption level of  
chemical processes, etc. The specific results are as follows.  
Ammonia from green hydrogen. The output of ammonia synthesis in China is generally stable,  
fluctuating around 50 Mt. In recent years, with the adjustment of industrial structure and the  
removal of excess capacity, the output of ammonia has been decreasing year by year, as  
shown in Figure 3.8. With the continuous breakthrough of ammonia fuel-related technologies,  
green ammonia has potential application in the energy field, but the demand for downstream  
fertilizers and other products is shrinking, and the output of ammonia synthesis in China will  
show a downward trend in the future. Based on the historical development and population  
projection, the future demand for ammonia is predicted. It is estimated that the annual demand  
for ammonia in China will reach 50-55 Mt in 2030, 41-43 Mt in 2050, and will drop below 40 Mt  
in 2060.  
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Green Hydrogen Demand Projection and Development Potential  
Figure 3.8 Historical Statistics of Ammonia Output and Growth Rate  
The cost of hydrogen production from renewable energy power generation is decreasing  
continuously. It is expected that ammonia production from green hydrogen has been applied  
on a large scale in 2030, with a cost of RMB 2.9/kg, which is at the same level as the average  
market price, with a replacement rate of 15%; the ammonia production capacity from green  
hydrogen will be further expanded and the replacement rate will be increased to about 65% by  
2050 with the integration coordination, upgrading and optimization of the electrolytic hydrogen  
production system and the Haber process ammonia production system; the ammonia  
production cost from green hydrogen will be reduced to less than RMB 2.4/kg in 2060, and the  
ammonia production replacement rate will reach more than 75%. In terms of hydrogen  
consumption level, the ammonia preparation technology is well developed and the process is  
complete. In the ammonia production process, about 0.2 tons of green hydrogen are  
consumed by preparing 1 ton of ammonia.  
Methanol synthesis from green hydrogen. Methanol is an important chemical raw material. At  
present, the production capacity of methanol synthesis in China is expanding rapidly. See  
Figure 3.9 for the production and growth rate of methanol in China from 2010 to 2019. Methanol  
is a kind of high-quality liquid fuel, which has great application potential in the energy field, and  
Figure 3.9 Historical Statistics of Methanol Output and Growth Rate  
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The Development and Outlook of Green Hydrogen  
the demand for methanol will show a rapid growth trend in the future. Based on the  
historical development, population projection and energy demand change, the future  
methanol demand is predicted. It is expected that the annual demand for methanol in  
China will reach about 65 Mt in 2030, increase to 100-110 Mt in 2050, and increase to more  
than 115 Mt in 2060.  
Under the combination of reduced green hydrogen costs and advances in the electrosynthesis  
of methanol, green hydrogen will be widely used in the field of methanol synthesis. It is  
expected that the preliminary demonstration application of methanol synthesis from green  
hydrogen will be realized in 2030 and a demonstration project of 100,000 tons will be  
completed; methanol synthesis from green hydrogen will be one of the economical technical  
routes by 2050, and the large-scale application of methanol synthesis from green hydrogen will  
be realized by optimizing the chemical process and developing efficient catalyst, with a  
replacement rate of 35%-40%; the cost of methanol synthesis from green hydrogen will further  
be reduced to less than RMB 2/kg in 2060, reaching the cost price level of traditional methanol  
synthesis, and the replacement rate will be increased to more than 40%. In terms of hydrogen  
consumption level, the synthesis of 1 ton of methanol in the electrosynthesis process of  
methanol consumes about 0.3 tons of green hydrogen, and the hydrogen consumption will  
decrease to about 0.25 tons in the future with the upgrading of technology and the increase of  
conversion rate.  
Synthetic methane from green hydrogen. China’s domestic natural gas reserves are low.  
Facing the increasing natural gas consumption demand, the natural gas import is increasing  
year by year, and the dependence on foreign countries is increasing year by year. In 2019,  
China’s natural gas import was 133 billion m3, accounting for 40% of the total demand. China’s  
natural gas output, import and growth rate are shown in Figure 3.10. Based on the historical  
development, population projection and energy demand change, the future demand for natural  
gas (methane) is predicted. It is expected that the annual demand for methane in China will  
reach about 340 Mt in 2030, and drop to about 250 Mt and 140 Mt in 2050 and 2060,  
respectively.  
Figure 3.10 Historical Statistics of Natural Gas Output,  
Import and Growth Rate in China  
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Green Hydrogen Demand Projection and Development Potential  
Under the combination of reduced green hydrogen costs and advances in synthetic methane  
technology, green hydrogen will gradually form a commercial application in the field of  
synthetic methane. It is expected that synthetic methane from green hydrogen will not be  
economical in 2030; by 2050, the cost of methane preparation will be reduced to less than  
RMB 2.4/m3, promoted in areas far away from natural gas production areas, with a  
replacement rate of 5%-10%, and by 2060, with the continuous reduction of green  
hydrogen cost, the application scope of synthetic methane will be further expanded and  
the replacement rate will be further increased to more than 10%. In terms of hydrogen  
consumption level, the technology of reducing carbon dioxide to synthesize methane from  
green hydrogen is stable, and preparing 1 ton of methane in the process flow consumes  
about 0.55 tons of green hydrogen.  
Considering the demand scale of ammonia, methanol and methane, the application  
replacement ability of green hydrogen and the hydrogen consumption of synthetic  
chemicals, the scale of hydrogen used in the green hydrogen chemical industry can be  
analyzed. Taking 2050 as an example, the projection process and results are shown in  
Figure 3.11. The total hydrogen consumption of the green hydrogen chemical industry is  
24million t/a, of which 5 million t/a of hydrogen is used for ammonia production, 11 million  
t/a of hydrogen for methanol production, and 8 million t/a of hydrogen for methane  
production.  
Figure 3.11 Process and Results of Hydrogen Projection for  
Green Hydrogen Chemical Industry in 2050  
The projection results of green hydrogen demand in the green hydrogen chemical industry in  
2030, 2050 and 2060 are shown in Table 3.3.  
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The Development and Outlook of Green Hydrogen  
Table 3.3 Projection of Green Hydrogen Demand in Future Green Hydrogen Chemical Industry  
Unit: 10,000 t  
Item  
2030  
5500  
150  
2050  
4200  
500  
2060  
Chemical demand  
Hydrogen energy demand  
Chemical demand  
Hydrogen energy demand  
Chemical demand  
Hydrogen energy demand  
Total  
3700  
500  
Ammonia  
Methanol  
Methane  
5000  
10  
11,000  
1100  
25,000  
800  
11,500  
1200  
14,000  
1000  
2700  
34,000  
0
160  
2400  
3.1.4.2 Metallurgy Sector  
In the field of metallurgy, steelmaking is the industry with the highest production capacity, and  
faces huge obstacles in electricity replacement. In order to achieve the low-carbon  
transformation of the metallurgical industry, hydrogen steelmaking technology is in urgent need  
of breakthroughs and applications. Besides steelmaking, hydrogen for metallurgy also involves  
the smelting process flow of metals such as tungsten and molybdenum, but the capacity is  
relatively low. The scale projection of hydrogen for metallurgy mainly focuses on steelmaking  
and its related factors, including changes in steel demand and hydrogen consumption level of  
ironmaking. The specific results are as follows.  
China’s steel industry has been developing rapidly. After 2012, the steel industry has  
maintained more than 1 billion tons, accounting for more than 50% of the global black metal  
market. The annual output and growth rate of Chinese steel are shown in Figure 3.12. Steel  
consumption is concentrated in real estate, infrastructure, machinery, automobile and other  
industries. With the gradual improvement of China’s future urbanization and the slowdown of  
population growth, the demand for steel in downstream industries will gradually shrink, and the  
demand for steel will gradually decrease. Based on the historical development and population  
projection, the future demand for steel is predicted. It is estimated that the annual steel  
demand in China will remain at around 1.1 billion tons in 2030, 750 - 800 Mt in 2050 and drop to  
below 750 Mt in 2060.  
With the lower cost of hydrogen production by renewable energy and the more  
comprehensive technology system of green hydrogen ironmaking and electric furnace  
steelmaking, green hydrogen will gradually become economically feasible in the  
metallurgical industry. It is estimated that by 2030, the green hydrogen ironmaking will  
realize the initial demonstration application, the hydrogen consumption cost will be  
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Green Hydrogen Demand Projection and Development Potential  
reduced to RMB 950/ton, and the capacity of the green hydrogen ironmaking  
demonstration project will reach 200,000 tons. In 2050, with the reduction of green  
hydrogen development cost and the breakthrough of hydrogen ironmaking technology  
development, the cost of hydrogen ironmaking will be reduced to RMB 500/ton, which is  
equivalent to the economics of blast furnace ironmaking, and the replacement rate is  
expected to increase to about 25%-30%. In 2060, the energy consumption cost of  
hydrogen ironmaking will be further reduced, equipment safety management and other  
issues will be comprehensively solved, and the replacement rate of green hydrogen  
ironmaking is expected to reach over 30%.  
Figure 3.12 Historical Statistics of Steel Output and Growth Rate  
In terms of hydrogen consumption level, the development of green hydrogen ironmaking  
technology is in the initial stage of research and development. In the future, with the  
increase of process flow management experience, the hydrogen utilization rate will be  
improved. It is expected that about 58kg of green hydrogen will be consumed by  
producing 1 ton of iron in the ironmaking process in 2030; after 2050, with deeper  
profoundation of reaction mechanism research level, and the breakthrough in reaction  
control method, the utilization rate of hydrogen and the metallization rate of products will  
continue to increase, and the amount of green hydrogen consumed to produce 1 ton of iron  
will drop to about 50 kilograms.  
Based on the comprehensive consideration of the demand scale of steel, the replacement  
capacity of green hydrogen application and the change of hydrogen consumption in  
ironmaking, the hydrogen scale for green hydrogen ironmaking is analyzed. Taking 2050 as an  
example, the projection process and results are shown in Figure 3.13. The total hydrogen  
consumption of green hydrogen ironmaking is 10 million t/a, and the projection results of green  
hydrogen demand in green hydrogen ironmaking industry in 2030, 2050 and 2060 are shown in  
Table 3.4.  
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The Development and Outlook of Green Hydrogen  
Figure 3.13 Process and Results of Hydrogen Projection for  
Green Hydrogen Ironmaking in 2050  
Table 3.4 Projection of Green Hydrogen Demand in Future Green  
Hydrogen Metallurgical Industry  
Item  
2030  
11.4  
20  
2050  
7.7  
2060  
7.5  
Steel output (100 Mt)  
Hydrogen energy demand (10,000t)  
Steelmaking  
1000  
1200  
3.1.4.3 Transportation Sector  
The projection of the hydrogen scale for transportation requires specific analysis of different  
types of vehicles such as small passenger cars, large passenger cars, heavy trucks,  
engineering vehicles, etc., considering various factors such as the inventory, energy  
consumption level, and usage methods of various vehicles, and the specific results as  
follows.  
The growth rate of China’s overall automobile inventory is gradually slowing down, however,  
the number of new energy vehicles and heavy-duty commercial vehicles is increasing rapidly.  
The inventory and growth rate of domestic automobiles and trucks in the recent five years are  
shown in Figure 3.14. In order to achieve carbon emission reduction in the transportation sector,  
it is expected that the share of new energy vehicles such as electric vehicles and hydrogen fuel  
cell vehicles will continue to increase in the future. Compared with electric vehicles, hydrogen  
fuel cell vehicles have advantages in trucks, engineering vehicles and other fields, and have  
the feasibility of large-scale promotion. At present, the inventory of trucks in China is not  
saturated, and it is expected that the future hydrogen scale for transportation will mainly focus  
on commercial vehicles such as trucks.  
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Green Hydrogen Demand Projection and Development Potential  
Figure 3.14 Status of Inventory of Cars and Trucks in China  
Combined with the population projection, the usage habits of various vehicles and the  
growth trend in recent years, the future inventory of cars is predicted. Taking 2050 as an  
example, the inventory of passenger vehicles will reach 460 million, including 1.1 million  
large passenger vehicles, 20 million small and medium-sized trucks and about 8 million  
heavy trucks.  
The development of hydrogen transportation will mainly focus on areas such as large  
passenger cars, buses, heavy trucks and engineering vehicles. The operation mode and route  
of public transportation are stable, and the demand for hydrogen refueling stations is low,  
which is one of the easiest modes of hydrogen transportation for large-scale commercial  
applications. With the decrease in the cost of hydrogen and the cost of vehicle fuel cells, the  
replacement rate of large passenger cars and buses with hydrogen fuel will reach 25%-30% in  
2050. Fuel cell vehicles will also show great development potential in logistics transportation.  
With the upgrading of fuel cell technology, the endurance mileage of fuel cell trucks will  
continue to improve. Fuel cell trucks will be competent for the transportation of goods in the  
same city and between cities, realizing clean application in the field of goods transportation,  
and the replacement rate of fuel cell trucks will reach 10%-15% by 2050. In the application field  
of engineering vehicles, hydrogen fuel cell vehicles have shown great application prospects,  
the required output power of engineering vehicles is low, the working area is fixed, and they  
have long-term stable working efficiency, which is a favorable condition for the application of  
FCVs. At present, fuel cell forklifts and other engineering vehicles have been commercialized  
on a certain scale. With the reduction of hydrogen cost, the replacement rate of hydrogen in the  
field of engineering vehicles will reach about 65% in 2050.  
With the continuous innovation of hydrogen fuel cell technology and the iterative upgrade of the  
whole vehicle integration technology of FCVs, the energy efficiency of FCVs will be  
continuously improved, and the hydrogen fuel consumption per unit mileage will be  
continuously reduced. In order to predict the average annual hydrogen fuel consumption of  
various hydrogen fuel cells, it is necessary to evaluate the mileage and hydrogen consumption  
level of cars according to the driving statistics and fuel cell conversion efficiency. Take 2050 as  
an example, the average annual mileage and hydrogen consumption per 100km of various  
hydrogen fuel cell vehicles are as follows.  
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The Development and Outlook of Green Hydrogen  
(1) The annual mileage of small and medium-sized passenger cars is 13,000-20,000km, and  
the average hydrogen consumption per 100km is about 0.7kg;  
(2) The annual mileage of large passenger cars and buses is 50,000-80,000km, and the  
average hydrogen consumption per 100km is 2-5kg;  
(3) The annual mileage of trucks is more than 100,000km, and the average hydrogen  
consumption per 100km is more than 4.5kg;  
(4) The annual mileage of engineering vehicles is less than 20,000km, and the average  
hydrogen consumption per 100km is about 0.9kg;  
(5) The annual mileage of civil aviation aircraft is within 2 million km, and the average hydrogen  
consumption per 100km is about 42kg.  
According to the inventory of different types of vehicles, the replacement rate of hydrogen  
fuel cell vehicles and the hydrogen consumption per kilometer, the total hydrogen  
consumption scale of hydrogen transportation can be obtained, and the results are shown  
in Figure 3.15. Take 2050 as an example, the total hydrogen consumption in the  
transportation industry is 15 million t/a, of which 2.8 million t/a for passenger cars, 1.2  
million t/a for buses, 10.4 million t/a for trucks and engineering vehicles, and 0.6 million t/a  
for civil aviation and navigation.  
Figure 3.15 Process and Results of Hydrogen Projection for Transportation in 2050  
The projection results of green hydrogen demand in the transportation industry in 2030, 2050  
and 2060 are shown in Table 3.5.  
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Table 3.5 Projection of Green Hydrogen Demand in Future Green Hydrogen Transportation  
Item  
2030  
2050  
46,000  
2060  
48,000  
Estimated inventory (10,000)  
Hydrogen replacement rate  
About 38,000  
About 1%  
Passenger  
vehicle  
About 5%  
About 75%  
Hydrogen energy demand  
(10,000t)  
40  
280  
420  
Estimated inventory (10,000)  
Hydrogen replacement rate  
About 100  
5%  
About 120  
About 25%  
About 130  
About 45%  
Bus  
Hydrogen energy demand  
(10,000t)  
30  
120  
140  
Estimated inventory (10,000)  
Hydrogen replacement rate  
2500  
2800  
3200  
Freight  
vehicle  
About 2%  
10%-15%  
15%-20%  
Hydrogen energy demand  
(10,000t)  
130  
1020  
1400  
Estimated inventory (10,000)  
Hydrogen replacement rate  
100  
180  
200  
Project  
Vehicle  
30%  
About 60%  
About 65%  
Hydrogen energy demand  
(10,000t)  
10  
20  
20  
Estimated inventory (10,000)  
Hydrogen replacement rate  
About 0.7  
—
About 2.1  
About 2%  
About 3.1  
About 4%  
Aviation  
Hydrogen energy demand  
(10,000t)  
0
30  
80  
Fuel consumption in the industry  
(10,000 t/a)  
About 2500  
About 3200  
About 3800  
Ship  
Hydrogen replacement rate  
—
0
About 3%  
30  
About 8%  
120  
Hydrogen energy demand  
(10,000t)  
Total  
200  
1500  
2200  
3.1.4.4 Hydrogen Generation  
With the clean transformation of the power system, the penetration rate of new energy such as  
wind and solar continues to increase, and the randomness of its generation output gradually  
becomes an important uncontrolled factor in the system, and the system volatility becomes  
increasingly strong. According to the time sequence analysis method commonly used in the  
power system, the time sequence of wind power, PV output and electricity load is divided into  
ultra-short time (seconds to minutes), short time (hours to days) and long time (week, month,  
year) according to different time scales to analyze their characteristics, corresponding to  
127  
The Development and Outlook of Green Hydrogen  
frequency modulation, daily peak regulation and seasonal peak regulation.  
On a long-term scale (in weeks), the seasonal variation trend of wind and solar resources is  
obvious. Taking North China as an example, wind power basically shows the characteristics of  
large in winter and small in summer, while PV shows the opposite characteristic. The  
foundation load is affected by the seasonal demand of public electricity consumption, holidays  
and other factors, showing the characteristics of the peak in winter and summer and low in  
spring and autumn. The net load is superimposed with the variations of wind, solar and  
foundation load, representing the characteristic of seasonal change and several weeks of  
fluctuation period, as shown in Figure 3.16. The existing various energy storage technologies  
are limited by the energy storage capacity and it is difficult to provide the adjustment capability  
of long-term time scale.  
Figure 3.16 Net Load Curve at Long-term Time Scale  
(Taking North China as An Example)  
Green hydrogen comes from electricity and can also be converted back to electricity through  
hydrogen power-generation technology. From the perspective of the power system, this  
process is equivalent to charging and discharging of energy storage. Compared with  
electricity, hydrogen is easier to store for a long time and on a large scale. Based on this  
characteristic, hydrogen generation can provide long-term seasonal regulation capability and  
reliable power supply guarantee capability for the new power system with new energy as the  
main body. The scale projection of hydrogen in generation needs to be determined according  
to the proportion and output characteristics of volatile new energy such as PV and wind power  
in the system, the regulating capacity of controllable power generation equipment such as  
hydropower, thermal power, nuclear power and biomass, and the demand for ensuring power  
supply under special circumstances such as extreme weather.  
According to the scenario of China Energy Interconnection, it is estimated that the total  
128  
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Green Hydrogen Demand Projection and Development Potential  
installed capacity of electricity sources in China will be 3800GW by 2030, including about 47%  
of the installed capacity of volatile new energy such as wind power and PV, 53% of other  
adjustable units and little demand for hydrogen generation by the system. With the maturity  
and progress of hydrogen generation technology, demonstration applications will be gradually  
carried out based on distributed hydrogen fuel cell generation. It is estimated that by 2050, the  
total installed capacity of electricity sources in China will reach about 7500GW, the installed  
capacity of volatile new energy such as wind power and PV will account for about 73%, the  
installed capacity of hydrogen generation will reach 100GW and the demand for hydrogen will  
be about 9 Mt. It is expected that by 2060, the total installed capacity of electricity sources in  
China will reach about 8000GW, the installed capacity of volatile new energy power generation  
such as wind power and PV will reach about 75%, and the installed capacity of hydrogen  
generation will reach about 200GW, and the hydrogen demand will reach about 10 Mt, meeting  
the needs of flexible regulation of the system and guaranteeing the reliability of power supply.  
3.1.4.5 Building Sector  
Hydrogen heating provides a choice for clean heat in the building sector. For the scale  
projection of hydrogen in heating, specific analysis needs to be carried out in sectors such as  
building, considering the changes in heating demand, the diversified development of building  
heating, the replacement capacity of hydrogen heating, and the level of energy conversion.  
The specific results are as follows.  
With the rapid development of China’s economy and society, life is more convenient and  
comfortable, and the per capita heating demand will be greatly increased in the future. The  
changes of heating area and growth rate in China in recent years are shown in Figure 3.17.  
According to the research report of IEA and other institutions, the current annual heating  
demand per capita in China is 2200kWh (about 8 GJ). With the improvement of China’s  
economic development and the diversification of heating, the per capita heating demand in  
China will increase significantly in the future. Based on the historical development and  
economic development projection, the heating demand is predicted. It is estimated that the  
annual heating demand per capita in China will reach about 11 GJ in 2030, more than 15 GJ in  
2050 and more than 16 GJ in 2060.  
Figure 3.17 Historical Statistics of Heating Area and Growth Rate in China  
129  
The Development and Outlook of Green Hydrogen  
Building heating will change from a single heating mode to a diversified heating mode, and  
green hydrogen will achieve partial clean replacement in the heating field, including the  
following methods. First, some decommissioned coal-fired boilers are transformed into  
gas-fired boilers in large-scale centralized heating areas in the north; second, hydrogen fuel is  
added to the natural gas transmission pipeline to meet the heating demand. It is estimated that  
the annual consumption of natural gas in China will reach 500 billion m³ by 2050. It is estimated  
that 3%-5% hydrogen can be added to the existing natural gas pipeline, and the hydrogen  
heating application of up to 2.2 million t/a can be realized; third, in the distributed energy  
system, hydrogen generation and heating are realized simultaneously through combined heat  
and power supply.  
Compared with electric heating, the heating cost of green hydrogen is higher, but hydrogen will  
play an extremely important role in the heating field as the cost of green hydrogen continues to  
decrease in the future. The mixed heating of hydrogen and natural gas is a transitional carbon  
reduction measure and an important way to utilize hydrogen in building heating. It is expected  
that the replacement rate of green hydrogen in the heating field will reach about 0.5% by 2050;  
by 2060, the diversified heating mode will continue to develop, and hydrogen will play a clean  
alternative role in centralized heating and distributed energy systems. As the cost of green  
hydrogen decreases below RMB 10/kg, the replacement rate of green hydrogen in the field of  
building heating will reach 1%. In terms of hydrogen consumption level, the average energy  
conversion efficiency of hydrogen-fired boilers can reach over 90%.  
Based on the comprehensive consideration of the change of heating demand scale, the  
replacement capacity of green hydrogen application and the hydrogen consumption in heating,  
the hydrogen scale for green hydrogen heating is analyzed. Taking 2050 as an example, the  
projection process and results are shown in Figure 3.18. The total hydrogen consumption of  
green hydrogen heating is 1 million t/a, and the projection results of green hydrogen demand in  
green hydrogen heating industry in 2030, 2050 and 2060 are shown in Table 3.6.  
Figure 3.18 Process and Results of Hydrogen Projection for Green Hydrogen Heating in 2050  
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Table 3.6 Demand Projection of Green Hydrogen in Heating Industry  
Item  
2030  
2050  
2060  
Per capita heating demand  
(GJ/year)  
About 11  
About 15  
About 16  
Building  
heating  
Population (100 million)  
14.6  
0
14  
13.3  
200  
Hydrogen energy demand  
(10,000t)  
100  
3.1.5 Demand Projection Results  
Based on the development trend and economic analysis of green hydrogen application  
technology and in combination with China’s energy consumption structure and characteristics,  
green hydrogen will play an important carbon mitigation role in the industry, power generation,  
and transportation fields. Based on the carbon neutrality scenario of the GEI, the demand  
projection is carried out in areas with greater hydrogen potential in future China’s chemical,  
metallurgical, power-generation, building , etc. according to the above model method. It is  
estimated that by 2030, China’s green hydrogen demand will be about 4 Mt, mainly from the  
transportation and chemical industries. It is estimated that by 2050, China’s green hydrogen  
demand will reach 61 Mt. In the industrial field, the new-type green hydrogen chemical industry,  
metallurgical, and industial high-quality heating require a total of 36 Mt of hydrogen (including  
hydrogen for methane and liquid fuel production), while in the transportation field a amount of  
15 Mt of hydrogen is required, and about 10 Mt of hydrogen in other fields including generation  
and building. It is estimated that by 2060, China’s green hydrogen demand will reach 75 Mt,  
and the total hydrogen demand will be about 95 Mt, accounting for about 10% of the final  
energy consumption. In addition to green hydrogen, about 20 Mt of industrial process  
hydrogen are produced in the internal segments of traditional industries such as petrochemical  
and coal chemical industry, mainly for self-production and self-use. In 2030 and 2060, the  
proportion of China’s hydrogen demand in various fields is shown in Figure 3.19, and the scale  
of hydrogen consumption and green hydrogen replacement rate in various industries in 2060  
are shown in Figure 3.20.  
Figure 3.19 Projection Results of China’s Hydrogen Demand in Various Fields in 2030 and 2060  
131  
The Development and Outlook of Green Hydrogen  
Figure 3.20 Projection Results of Green Hydrogen Replacement  
Rate in China’s Sub-Industries in 2060  
Considering the cost of carbon emissions, the cost-effectiveness advantages of green  
hydrogen replacing fossil fuels in the industry, generation, and transportation fields will be  
quickly reflected. According to the calculation of CO2 emissions cost of RMB 50/t, the cost of  
ammonia production from coal is increased by about RMB 200/t, and that of ammonia  
production from natural gas is increased by about RMB 100/t; the cost of methanol production  
from coal is increased by RMB 150-200/t, and that of methanol production from natural gas is  
increased by RMB 80-100/t; the cost of blast furnace ironmaking is increased by about RMB  
80/t; the cost of natural gas generation will increase by RMB 7.2/MWh; the operating cost of  
fuel passenger cars will increase by RMB 1.1/100km. With the increase of CO2 emissions cost,  
the application cost-effectiveness of green hydrogen in these fields will become more obvious.  
3.1.6 Scenario of China Energy Interconnection  
Through the projection of the potential for green hydrogen demand, GEIDCO, based on the  
scenario of “electricity replacement”, proposes the scenario of “electricity + hydrogen energy”  
for China Energy Interconnection. Based on the construction of energy interconnection, clean  
replacement is implemented for energy production. Through large-scale development,  
large-scale allocation and efficient use of clean energy, fossil fuels dependence is eliminated,  
phase-out of fossil fuels and zero-carbon energy supply are accelerated, and a clean  
energy-dominant energy system is established; the mode of energy consumption is replaced  
by electricity + hydrogen energy, which is transformed from coal, oil, gas, etc.. to  
electric-centric and synergistic transformation of electricity and hydrogen. Electricity and  
hydrogen become the core carriers of final energy consumption, the level of final electrification  
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Green Hydrogen Demand Projection and Development Potential  
(including indirect electrification realized by green hydrogen applications) is improved, and the  
efficiency of energy use is improved.  
At the early peaking stage (before 2030), the application of green hydrogen is still in the initial  
stage, and the key is the peaking of coal and petroleum. The total consumption of fossil fuels  
will reach its peak in 2028, in which the total consumption of coal stabilized at around 2800 Mt  
after 2013, and will start to decline after reaching the peak of electrical coal in 2025. The total  
oil consumption will gradually decrease after reaching its peak before 2030, with the peak  
value of about 740 Mt. In 2030, the clean energy consumption will account for 31% of primary  
energy consumption. The electricity consumption of the whole society is 10,700 TWh, the  
electrification rate reaches 33%, and the electricity exceeds coal, oil and natural gas as a  
dominant energy source for final energy consumption.  
In the rapid mitigation stage (2030—2050), it is essential to accelerate the renewable energy  
development, increase the proportion of electricity replacement and accelerate the application  
of green hydrogen. The total consumption of fossil fuels will drop to 1.39 billion tons of standard  
coal equivalent in 2050, and the scale of clean energy consumption will be accelerated,  
accounting for 75% of the primary energy. The electricity consumption of the whole society  
reaches 16,000 TWh, of which about 2.7 trillion is used for hydrogen production, the demand  
for green hydrogen is 61 Mt, and the electrification rate reaches 58%.  
Figure 3.21 Total Amount and Structure of Primary Energy  
At the overall neutrality stage (2050—2060), it is essential to achieve deep decarbonization of  
energy consumption through electricity replacement+hydrogen replacement. Strengthen  
hydro, wind, solar and other renewable energy development, and promote the comprehensive  
consumption of clean electricity, which is basically met by clean energy. In 2060, the total  
consumption of fossil fuels will drop to 650 Mt of standard coal equivalent, and the scale of  
clean energy consumption will further expand, accounting for 90% of primary energy,  
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The Development and Outlook of Green Hydrogen  
achieving a comprehensive transition of the energy production system, accelerating the  
transition of the remaining fossil fuels consumption to non-energy application, and giving full  
play to the value of fossil fuels. The electricity consumption of the whole society reaches 17,000  
TWh, of which about 3000 TWh is used for hydrogen production, and the demand for green  
hydrogen is 75 Mt, with an electrification rate of 66%.  
Figure 3.22 Total Amount and Structure of Final Energy Consumption  
3.2 Development Potential and Cost  
“Green hydrogen” is the most important development direction of hydrogen production  
technology in the future. With the reduction of the cost of renewable energy power generation,  
areas with sufficient wind and solar resources and suitable for centralized development can be  
used as cheap and low-carbon hydrogen sources, and electrolytic hydrogen production  
equipment and related industries can be arranged there. The scale of green hydrogen  
development potential and the distribution of low-cost green hydrogen should be clarified first  
in future green hydrogen development. These issues are related to whether the development of  
green hydrogen can be combined efficiently and economically with the development of  
renewable energy, fully support the development of China’s hydrogen energy industry and  
contribute to the realization of carbon neutrality in the whole society. Therefore, it is necessary  
to establish a systematic and comprehensive algorithm model to comprehensively evaluate the  
technological exploitable amount, development cost and distribution of green hydrogen.  
Based on the research foundation and related achievements of GEIDCO in the fields of cost  
projection of clean energy generation technology and global clean resources assessment, the  
report further comprehensively considers the regional resource development potential, wind  
and solar complementary characteristics, hydrogen production technology and  
cost-effectiveness and other multiple factors, constructs the global green hydrogen production  
potential assessment algorithm and cost optimization model, and completes the green  
134  
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Green Hydrogen Demand Projection and Development Potential  
hydrogen production potential assessment and cost distribution research in China with the  
help of advanced calculation tools such as linear programming optimization algorithm and  
geospatial big data analysisA,B. The research idea is shown in Figure 3.23.  
Figure 3.23 Schematic Diagram of Green Hydrogen Production Potential and Cost Assessment  
3.2.1 Cost Projection of New Energy Power Generation  
Clean energy power generation is the key technology to realize clean replacement, and it is  
also an important prerequisite to promote the production and application of green  
hydrogen. According to the GEIDCO’s research on the development and prospect of new  
energy power generation technology based on the dual IAM (RL-BPNN)C, wind power and  
photovoltaic power generation technology will continue to mature and update iteratively in  
the future, and the investment cost of equipment and new projects will continue to maintain  
the momentum of rapid decline in recent years. It is expected that the average initial  
investment in onshore wind power in China will decrease to RMB 5300/kW and the LCOE  
will be RMB 0.25/kWh by 2030; the PV development cost also shows a rapid decline trend,  
and the average initial investment will decrease to RMB 2700/kW and the LCOE will be  
RMB 0.15/kWh. By 2060, the average initial investment in onshore wind power in China will  
be reduced to RMB 3100/kW and the LCOE will be RMB 0.14/kWh; the PV development  
cost also shows a rapid decline trend, and the average initial investment will be reduced to  
RMB 1200/kW and the LCOE will be RMB 0.07/kWh.  
AGEIDCO, Research on Development of and Investment in Global Renewable Energy [M], China Electric  
Power Press, November 2020.  
B,CGEIDCO, Development and Outlook of Clean Energy Power Generation Technology [M], China Electric  
Power Press, November 2020.  
135  
The Development and Outlook of Green Hydrogen  
3.2.2 Assessment of New Energy Resources  
The assessment of wind power and photovoltaic power generation resources is the key basis  
for evaluating the potential and cost of green hydrogen production. On the basis of  
establishing a global database of clean energy resources, the GEIDCO has built a  
sophisticated digital assessment model, developed the Global Renewable-energy  
Exploitation ANalysis platform (GREAN), completed clean energy development and  
investment researchA in the world and six continents, and conducted theoretical,  
technical and economic multi-dimensional quantitative assessment research on wind and  
solar resources worldwide.  
1. Data and methods  
In terms of data, to further meet the needs of digital and multi-dimensional assessment,  
geographic information data such as land cover distribution and data related to human  
activities such as transportation and power grid infrastructure distribution are introduced in the  
report on the basis of resource data, to establish a computable basic information database  
including 3 categories and 18 items covering the whole world by using a data fusion algorithm,  
as shown in Appendix 1.  
In the aspect of model, a set of well-defined, systematic, comprehensive and operable  
algorithms and multi-dimensional quantitative assessment models are constructed, and the  
scientific connotation, assessment process, calculation method and recommended  
parameters of main assessment indicators are clarified. The technical route for wind and solar  
resources assessment is shown in Figure 3.24, and the assessment parameters and grid  
connection parameters are shown in Appendix 2.  
2. Assessment results  
The technical potential installed capacity of wind power suitable for centralized  
development in China is about 5.6TW, and the annual power generation is about 14PWh.  
The technically developable wind energy resources in China are mainly concentrated in  
Northwest and North China, accounting for more than 90% of the country’s total. The wind  
energy development conditions in Inner Mongolia and Xinjiang are extremely superior, and  
the proportion of resources reaches 51% and 26% of the country’s total. Most areas in  
eastern and southern China are densely populated, developed in agriculture and widely  
distributed in cultivated land. The western Qinghai-Tibet Plateau has a high altitude and a  
large terrain relief. Southwest China, South China, especially Hainan and other places are  
widely covered with dense tropical rain forests, which does not meet the conditions for  
centralized construction of large bases. On the whole, due to the impacts of land cover,  
topography and other factors, about 16% of the land areas in China have centralized  
development conditions, and the eastern and central regions can develop wind power  
resources by using distributed development mode and idle land around villages, forests  
AGEIDCO, Research on Development of and Investment in Global Renewable Energy [M], China Electric  
Power Press, November 2020.  
136  
3
Green Hydrogen Demand Projection and Development Potential  
and in fields.  
Figure 3.24 Technical Roadmap for Assessment of Wind and Photovoltaic Power Resources  
The scale of photovoltaic power generation suitable for centralized development is 117.2TW,  
and the annual power generation is as high as 193PWh. The technically developable  
photovoltaic resources are mainly concentrated in the northwest, north and southwest regions  
of China, of which the northwest region accounts for more than 60% of the national volume.  
Xinjiang, Inner Mongolia and Qinghai provinces have excellent conditions for centralized PV  
resources development. Similar to wind power development, there are a large number of towns  
and farmland in the eastern and southern regions. The complex terrain of Qinghai-Tibet Plateau  
makes the project construction difficult, and the forests in southwest and south China are  
dense, which are not suitable for large-scale development of PV. Generally speaking, affected  
by factors such as land cover, topography, etc., about 32% of the land areas in China have  
137  
The Development and Outlook of Green Hydrogen  
centralized PV development conditions, and the eastern and southern regions can develop  
photovoltaic power generation resources by using distributed development mode and idle land  
in fields and urban roofs.  
Based on the projection results of the technical cost of wind power and photovoltaic power  
generation, considering the transportation and grid infrastructure conditions comprehensively,  
the areas with lower costs for centralized wind power development are mainly concentrated in  
Inner Mongolia, northeast Xinjiang, central Ningxia, northern Shaanxi and Hebei, western Jilin  
and Liaoning, and some areas in central Yunnan. The centralized PV generally has good  
conditions for large-scale development. The areas with low development costs are mainly  
concentrated in most areas of Inner Mongolia, Xinjiang and Qinghai, as well as Gansu, Shaanxi,  
Yunnan, Tibet and Guangdong.  
3.2.3 Development Potential and Cost Optimization Model  
The total upper limit of the technical development potential for green hydrogen production  
is mainly determined by the technical developability of regional wind power and PV  
resources, which generally far exceeds the actual demand for hydrogen in the whole  
society. Therefore, in the actual development process, it is necessary to pay attention to  
which regions have the best cost-effectiveness for green hydrogen production and how to  
combine it with new energy development.  
The cost of green hydrogen is not a simple correspondence with the cost of green electricity,  
and the economic development potential assessment and cost analysis are the process of joint  
optimization by multivariable coupling. The assessment of the economic potential for green  
hydrogen development and cost optimization study shall be carried out based on the technical  
and economic parameters such as the cost of wind and solar power generation and the cost of  
electrolytic hydrogen production equipment, further combined with the actual operational  
constraints such as the output and complementary characteristics of wind and solar resources,  
the objective of reasonable power abandonment and the utilization rate of electrolytic  
equipment, with the minimum cost of green hydrogen production as the optimization objective,  
and the LP theory used for modeling analysis to finally obtain the green hydrogen cost and  
optimized development scheme.  
3.2.3.1 Ideas of Modeling  
The modeling researches on the economic development potential and cost optimization of  
green hydrogen include 4 key segments, and a mathematical model is constructed  
respectively. The modeling idea is shown in Figure 3.25. First, a clean energy development  
model, which uses the complementary characteristics of wind and solar resources to carry out  
collaborative development, which will effectively increase the comprehensive full-load hours  
and reduce development costs. Based on the cost analysis and resource evaluation research  
of new energy power generation technologies, the output characteristics of wind and solar  
resources and the technological development capacity as well as the development cost can  
be obtained to build the upper limit function of installed capacity. Second, a model of green  
hydrogen production scale, based on the principle of time-sequence balance, is established to  
establish a time-sequence constraint model for wind, solar and electrolysis cell output, and to  
138  
3
Green Hydrogen Demand Projection and Development Potential  
establish a constraint model for abandoned electricity that limits the maximum electricity  
abandonment rate. Third, a cost-effectiveness model, using the LCOH as the assessment  
indicator, constructs its mathematical expression model, which mainly includes the annual cost  
of wind and solar power generation, the annual investment in the hydrogen production  
system, the annual operation and maintenance, etc., and puts forward the projection  
method of total hydrogen production. Fourth, an LP optimization model, aiming at the  
lowest cost of hydrogen production, establishing a solution function, optimizing the  
cooperative configuration scheme of wind and solar development and electrolytic cell  
scale to meet the demand of hydrogen production, and obtaining the lowest cost of  
hydrogen production. Finally, based on the GIS algorithm, the optimal distribution map of  
green hydrogen production potential and cost is drawn.  
Figure 3.25 Schematic Diagram of Green Hydrogen Potential and Cost Optimization Modeling  
3.2.3.2 Mathematical Model and Boundary Conditions  
1. Development model for clean energy  
On the basis of the assessment of wind and solar resources, the following constraints are put  
forward for the installed capacity of wind powerCapwindiI and PV CapPV I in independent  
i
geographic grids i:  
0≤CapwindiI ≤CAPWINDI ,∀i  
i
Formula 3-1  
0≤CapPViI ≤CAPPViI ,∀i  
Formula 3-2  
Formula 3-3  
CAPWINDI ,CAPPViI ≥0,∀i  
i
Among them, CAPWINDI andCAPPViI are the technical exploitation amount of wind power  
i
and PV resources in geographic grids respectively, i.e. the upper limit of the installed capacity  
scale, and I refers to all geographic grids in the area to be developed, i.e. the number of grid  
points involved in optimization.  
2. Green hydrogen production scale model  
Furthermore, the theoretical values ωiI,t and φiI,t of the output of wind power and PV at the  
139  
The Development and Outlook of Green Hydrogen  
time of t in the grid are introduced and the variables PI , PI,Cur respectively represent the  
i,t  
i,t  
output and abandonment power of the electrolytic cell. The mathematical expressions are as  
follows. Set the initial period t=0 and the last period t=NT, with the value of NT taken as 8760h  
(i.e. annual balance).  
PI + PI,Cur = ωiI,tCapwindiI +φiI,tCapPV I ,∀i,t  
Formula 3-4  
i,t  
i,t  
i
In practical engineering, it is generally allowed to abandon electricity reasonably, i.e. to cut off  
part of the peak output of wind and solar to ensure the reasonable full-load hours of electrolysis  
cells (higher than 3500h), improve the equipment utilization rate, avoid the increase of average  
hydrogen production price and ensure the project cost-effectiveness. Therefore, the upper limit  
λ of the electricity abandonment rate is set in the model, and the constraint that the actual  
electricity abandonment rate λiI shall be lower than the upper limit λ is put forward. CapiI is  
the capacity scale of electrolytic cells, and its mathematical expression equation is as follows:  
CapI = max PI  
Formula 3-5  
Formula 3-6  
(
)
i
i,t  
NT  
PI  
i,t  
λiI =1−  
,∀i,t  
t=1  
NT  
NT  
CapwindI ωI + CapPV I φI  
i   
i   
i,t  
i,t  
t=1  
t=1  
PI , PI, Cur ≥0,∀i,t  
Formula 3-7  
Formula 3-8  
Formula 3-9  
i,t  
i,t  
0≤ωiI,t ≤CapwindiI ,0≤φiI,t ≤CapPViI ,∀i,t  
0≤λiI ≤λ ≤1  
A single geogrid point needs to meet the above output time-sequence balance and electricity  
abandonment constraints. For the geogrid point group I involved in optimization, the constraint  
equation for the total amount of green hydrogen production TotalH is proposed, and the  
mathematical expression is as follows:  
NT  
I
I
TotalH =  
TotalH = α  
PI ,∀i,t  
Formula 3-10  
  
i
i,t  
i=1  
i=1 t=1  
3. Cost-effectiveness model of green hydrogen production  
On the basis of the sum of the development costs of wind and solar power in each independent  
geographic grid obtained from the assessment of wind and solar resources,  
LCOEwindiI and LCOEPV I , the mathematical expression of green hydrogen production  
i
cost LCOHiI is as follows. Among them, LCOEiI is the electricity cost of wind-solar  
collaborative development, CAPEXiI is the annual investment in the hydrogen production  
system and OPEXiI is the annual operation and maintenance cost of the hydrogen production  
system. It is assumed that the investment and operation cost of wind and solar power  
generation equipment has been included in the development cost LCOEwindiI and  
140  
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Green Hydrogen Demand Projection and Development Potential  
LCOEPV I calculation, without considering the penalty of abandoned electricity of clean  
i
energy.  
LCOEiI + CAPEXiI + OPEXiI  
LCOHiI =  
,∀i  
Formula 3-11  
TotalHiI  
NT  
NT  
LCOEI = LCOEwindICapwindI ωI + LCOEPViICapPV I φI ,∀i,t  
i   
i   
i
i
i, t  
i,t  
t=1  
i=1  
Formula 3-12  
Formula 3-13  
NDep  
CapiI ICγIRR (1+γIRR  
)
CAPEXiI =  
,∀i  
NDep−1  
(1 + γIRR  
)
OPEXiI = CapiI ICδFIX ,∀i  
Formula 3-14  
Formula 3-15  
Formula 3-16  
LCOEwindiI ,LCOEPV I ,α, IC, NDep ≥0,∀i  
i
0≤γIRR ,δFIX ≤1  
Among them, the hydrogen production efficiency α is 0.22m3/kWh (i.e. the electrolysis  
efficiency is 80%); IC is the unit investment cost of electrolytic hydrogen production system,  
with the value of RMB 3000/kW; γIRR is the internal rate of return, with the value of 8%; NDep is the  
depreciation period, with the value of 20 years; δFIX is the OPEX coefficient of the electrolysis  
cell, with a value of 2%.  
4. Production cost optimization model for green hydrogen  
On the basis of the above modeling, the production cost optimization model is established with  
the lowest cost of green hydrogen as the objective, and its mathematical expression is as  
follows.  
arg min f CapI , CapwindI ,CapPV I  
=
(
)
i
i
i
No∞  
N*  
Nr  
CapiI ICγIRR (1+ γIRR  
)
LCOEwindICapwindI ωI + LCOEPV ICapPV I φI + −  
+ CapiI ICδFIX  
i   
i   
i
i,t  
i
i, t  
No∞  
(1+ γIRR  
)
−1  
t=1  
t=1  
TotalH  
s.t.  
Constraint sets 2-1,2-10  
It can be seen that the hydrogen production cost is jointly affected by many coupling variables,  
mainly including wind and solar development cost, electrolytic hydrogen production equipment  
cost, wind and solar development scale, electrolytic hydrogen production scale after  
reasonable electricity abandonment, etc. An LP optimization model is studied and constructed  
to solve the minimum hydrogen production cost. Figure 3.26 shows the impact of different wind  
and solar power development schemes and different levels of electricity abandonment on  
green hydrogen cost. The optimization solution can obtain the global optimal solution shown in  
the figure.  
141  
The Development and Outlook of Green Hydrogen  
Figure 3.26 Schematic Diagram of The Impacts of Wind-solar  
Proportion and Electricity Abandonment Rate on Green Hydrogen Cost  
Considering the massive data and operational requirements brought about by nearly 50 million  
geogrid points covered by China’s territory, a “resource - assessment - demand hierarchical  
optimization algorithm” is established for zoning optimization (see Appendix 3) to obtain the  
coordinated configuration scheme of wind-solar development and electrolytic hydrogen  
production for each grid point and the minimum hydrogen production cost. Based on the  
research and judgment on the development of hydrogen production technology, the  
distribution map of green hydrogen production potential (technical exploitation amount) and  
green hydrogen production cost in China are drawn.  
3.2.4 Assessment Results  
The production potential of green hydrogen is huge, far exceeding the level of hydrogen  
demand. Considering the resource endowment, development difficulty and technical level of  
wind power and solar photovoltaic power generation in China, it is estimated that the annual  
technical exploitation amount of onshore wind power and photovoltaic power generation is 14  
PWh and 193 PWh respectively. If all these wind and solar resources are involved in hydrogen  
production, the technological development limit of green hydrogen in China is 3.7 billion t/a,  
which is about 40 times the total hydrogen demand in 2060. Northwest China has great  
potential for green hydrogen production, accounting for 50% of the country’s yield. Therefore,  
from the perspective of wind and solar resources, it can fully meet the needs of green  
hydrogen production in China in the future. The distribution of green hydrogen production  
potential in China is shown in Figure 3.27.  
An optimized development scheme based on the resource endowment characteristics of the  
region can maximize the cost-effectiveness of green hydrogen production. The cost of green  
hydrogen production in well-conditioned areas in the west and north can be as low as RMB  
15-16/kg by 2030. According to the optimized calculation, the average green hydrogen  
production cost in China is about RMB 20/kg in 2030. The optimized installed capacity ratio of  
wind power and solar power generation at different grid points is 1:1.5-3, the electricity  
abandonment rate is 2%-7%, the spatial distribution of green hydrogen production cost and  
wind-solar LCOE show a certain similarity, and the regions with cost-effectiveness advantages  
are mainly concentrated in most regions of Inner Mongolia, northeastern Xinjiang, western  
Liaoning, northwestern Shaanxi, Ningxia and central Yunnan. At the same time, in areas with  
relatively good transportation and grid infrastructure, the production cost of green hydrogen in  
some areas is as low as RMB 15-16/kg. The schematic diagram of green hydrogen production  
cost distribution in China in 2030 is shown in Figure 3.28.  
142  
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Green Hydrogen Demand Projection and Development Potential  
Figure 3.27 Schematic Diagram of The Potential Distribution of Green Hydrogen Production in China  
Figure 3.28 Schematic Diagram of Green Hydrogen Production Cost Distribution in China in 2030  
143  
The Development and Outlook of Green Hydrogen  
By 2050, the green hydrogen production cost in China will reach RMB 7-11/kg, which can be  
as low as RMB 7-8/kg in well-conditioned areas in the west and north. Green hydrogen is the  
most important production method of hydrogen, beyond blue hydrogen and grey hydrogen in  
terms of cost-effectiveness in an all-round way. The schematic diagram of green hydrogen  
production cost distribution in China in 2050 is shown in Figure 3.29.  
Figure 3.29 Schematic Diagram of Green Hydrogen Production Cost Distribution in China in 2050  
By 2060, the average production cost of green hydrogen in China will be about RMB 6-10/kg,  
which can be as low as RMB 5-7/kg in well-conditioned areas in the west and north. The  
schematic diagram of green hydrogen production cost distribution in China in 2060 is shown in  
Figure 3.30.  
3.3 Summary  
Deep decarbonization is the fundamental driving force to accelerate the application of green  
hydrogen. Based on the development trend and economic analysis of green hydrogen  
application technology and in combination with China’s energy consumption structure and  
characteristics, green hydrogen will play an important carbon mitigation role in the industry,  
power generation, and transportation fields. On the energy supply-side, hydrogen power  
generation is an important long-term regulating and supporting power supply for a high  
proportion of new energy power systems; on the energy consumer-side, hydrogen will be  
focused on areas difficult to be directly electrified in chemical, metallurgical, aviation, etc. to  
realize indirect electricity replacement.  
144  
3
Green Hydrogen Demand Projection and Development Potential  
Figure 3.30 Schematic Diagram of Green Hydrogen Production Cost Distribution in China in 2060  
It is estimated that the demand for green hydrogen in China will gradually increase in the next  
decade, and by 2030, the demand for green hydrogen will be about 4 Mt. China’s demand for  
green hydrogen will increase rapidly to 61 Mt by 2050. Among them, 36 Mt hydrogen for new  
industries such as power to raw material and metallurgy, 15.5 Mt hydrogen for transportation  
such as large passenger cars and heavy trucks, and 9.5 Mt hydrogen for power generation  
and construction industries. By 2060, the demand for green hydrogen in China is expected to  
reach 75 Mt, and the demand for hydrogen in traditional industries such as petrochemical  
industry and others is expected to be 20 Mt and it will still be met by hydrogen in the industrial  
process. The total demand for hydrogen is expected to reach 95 Mt. Based on the economic  
development model and industrial structure of provinces and regions in China, by 2050 and  
2060, the demand for green hydrogen is expected to be mainly concentrated in central and  
eastern China, accounting for 85% of the country’s total.  
With great potential for green hydrogen development, the development layout shall be  
optimized by taking into account the distribution of renewable energy resources, water sources,  
equipment utilization, etc. Considering the resource endowment, development difficulty and  
technical level of renewable energy resources in China, if all wind and solar power resources  
are used for green hydrogen production, the annual output can be 3.7 billion tons, about 40  
times the total hydrogen demand in 2060. The development potential of green hydrogen in  
China is mainly concentrated in northwest China, accounting for 50% of the country’s total.  
Therefore, the amount of wind and solar resources can meet the requirements of China’s future  
green hydrogen production, and it is important to optimize the ratio of wind and solar to  
hydrogen production equipment, so as to improve the cost-effectiveness of green hydrogen  
145  
The Development and Outlook of Green Hydrogen  
production.  
According to the optimization model, the cost of green hydrogen preparation in well-  
conditioned areas in the west and north by 2030 can be as low as RMB 15-16/kg, which is  
beginning to show cost-effectiveness compared with blue hydrogen. By 2050, the cost of  
large-scale centralized development of green hydrogen in some well-conditioned areas in the  
west and north can be as low as RMB 7-8/kg, and green hydrogen becomes the mainstream  
hydrogen production mode. The cost of green hydrogen will be further reduced to RMB 5-7/kg  
by 2060.  
146  
4
Electricity-Hydrogen Coordinated Zero-carbon Energy System  
Electricity-Hydrogen  
Coordinated Zero-  
carbon Energy  
System  
The Development and Outlook of Green Hydrogen  
Green hydrogen comes from green electricity and is widely used in energy  
consumption fields that cannot be directly electrified. Both of them constitute the  
main body of the zero-carbon energy system. In the study of allocation and  
layout of energy resources, electricity or hydrogen should not be considered  
separately, but they should be optimized as an important part of the energy  
system in an overall way to achieve the safe, cost-effective, and efficient  
allocation of energy resources.  
In this chapter, an electricity-hydrogen coordinated zero-carbon energy system  
model is built, and it includes the technical links of production, transmission, and  
storage of green electricity and green hydrogen. With the goal of optimizing the  
cost-effectiveness of the whole system, the power, grid, load, and storage  
elements are optimized, and a series of issues such as “how to allocate green  
hydrogen” and “how to coordinate green hydrogen allocation with green electricity  
allocation” are systematically studied. The systematic value of diversified energy  
allocation is quantitatively analyzed based on multiple schemes.  
4.1 Necessity of Electricity-Hydrogen Coordinated Allocation  
Due to the unbalanced distribution of natural resources, China’s clean energy resources and  
energy demand show the characteristics of reverse distribution in terms of geographic  
relations.  
In terms of clean energy resources, the western region is rich in wind energy and solar energy  
resources and the population is sparse, which is conducive to the development of large-scale  
bases. For example, the technical potential installed capacity of wind power and PV power in  
five provinces of northwestern China reaches 2350 GWh and 73,750 GWh respectively, far  
exceeding the local energy demand level. The clean energy resources in the central and  
eastern regions are relatively poor, and the land supply is relatively tight. The distributed PV  
power can be developed on the roof of the building or the decentralized wind power can be  
developed in the surrounding areas of urban and rural areas. The offshore wind power of a  
certain scale can be centrally developed in the coastal regions, which can meet some local  
demands for electricity consumption and electrolytic hydrogen production.  
In terms of green hydrogen production cost, the green hydrogen production cost of clean  
energy bases with good conditions in western China is expected to reach about RMB 5-7/kg,  
the cost of hydrogen production by the distributed power generation in central and eastern  
China is expected to reach RMB 11-14/kg, and the cost of hydrogen production by offshore  
wind power in coastal areas of eastern China is expected to reach about RMB 20/kg by 2060,  
so the green hydrogen production in western China has obvious economic advantages.  
148  
4
Electricity-Hydrogen Coordinated Zero-carbon Energy System  
In terms of hydrogen demand, the population is dense, economic development is rapid, and  
energy demand is strong in eastern and central China, so it is the energy load center. The  
hydrogen demand is expected to account for 85% of the country’s total by 2060. The aggregate  
economic output in western China is small and the hydrogen demand is relatively small.  
For green hydrogen, there is a problem of how to transmit it from the production base to the  
demand center like green electricity. Solving the problem is an important task for building a  
zero-carbon energy system, and it is also the basis for the wide application and rapid  
development of hydrogen energy.  
4.2 Optimal Allocation Model  
4.2.1 Model and Algorithm  
In the report, an electricity-hydrogen coordinated system model is built, and the coordinated  
optimization and quantitative analysis are carried out on the production, transmission, storage,  
allocation and utilization of different energy sources from the system level, to quantitatively  
evaluate the systematic value of the connection between electricity and hydrogen, analyze the  
relationship between power transmission and hydrogen transportation, and systematically  
study the optimal way of hydrogen energy allocation in China.  
1. Model structure  
The electricity-hydrogen coordinated system model consists of multiple nodes. Each node  
includes various technical equipment such as renewable energy power generation, electrolytic  
hydrogen production, hydrogen power generation, electricity storage, and hydrogen storage.  
All the nodes have their own demands for electricity and hydrogen, and the nodes are  
connected by power transmission and hydrogen transportation equipment. Various  
technologies are modeled separately, and the combination and connection relationships are  
shown in Figure 4.1.  
Figure 4.1 Schematic Diagram of Electricity-Hydrogen Coordinated Energy System  
149  
The Development and Outlook of Green Hydrogen  
2. Optimization algorithm  
Based on the different demand for electricity and hydrogen at the receiving end and the  
sending end and the characteristics of renewable energy resources, the electricity-hydrogen  
coordinated system model, aiming at the minimum comprehensive energy consumption cost of  
the whole system, optimizes the scale and operation mode of various equipment such as  
power generation, electrolytic hydrogen production, energy storage, hydrogen storage, power  
transmission, and hydrogen transportation in an overall manner, and carries out the hourly  
analysis of balance between supply and demand of different energy varieties such as  
electricity and hydrogen throughout the year of 8760 hours. The optimization calculation  
architecture of the model is shown in Figure 4.2. The main output results include the overall  
scale data of the system (including installed capacity of various power generation equipment,  
capacity of power transmission and hydrogen transportation channels, output of different  
energy varieties, levelized cost, and full-load hours) and hourly operation data of various  
equipment (including generator unit power, energy storage charge and discharge power, and  
transmission power of power transmission and hydrogen transportation equipment). The  
mathematical expressions of optimization objectives and constraints of the model are detailed  
in the Appendix 4.  
Figure 4.2 Basic Architecture of Electricity-Hydrogen Coordinated System Model  
4.2.2 Analysis of Typical Scenarios  
In combination with the development trend of hydrogen energy in China, the research target  
year is set to 2060. Based on the characteristics of reverse distribution of production and  
consumption of green hydrogen, the study focuses on the power transmission and hydrogen  
transportation allocation of the electricity-hydrogen coordinated system in the point-to-point  
scenario (with the transportation distance of 2000km) with clean energy bases in northwestern  
150  
4
Electricity-Hydrogen Coordinated Zero-carbon Energy System  
China as the energy supply end and central China as the energy receiving end. For other  
scenarios with different transportation distances, different hydrogen transportation and power  
transmission technologies can be selected, and the same model method can be used for  
quantitative analysis.  
1. Boundary condition  
Renewable energy power generation equipment includes wind power, PV power, and  
concentrating solar power equipment. The generated output of the three technologies is  
affected by resource characteristics, especially the wind power and PV power have obvious  
fluctuation and intermittence. Based on the actual distribution of wind and solar energy  
resourcesA, three development areas are selected in northwestern China respectively. The  
wind and solar energy resources are excellent, and the cost of hydrogen production from wind  
and solar energy resources is about RMB 5-7/kg.  
The output characteristics of typical wind power and PV power in the selected development  
areas are shown in Figure 4.3 (in hours).  
Figure 4.3 Output Characteristics of Wind Power and Solar PV Power in Western China (Hours)  
By 2060, the construction costs of wind power, PV power, and concentrating solar power are  
expected to be reduced to RMB 3600/kW, RMB 1500/kW, and RMB 15,000/kW respectively.  
In terms of energy demand, the demands for electricity and hydrogen in east-central China  
AData Source: Global Renewable-energy Exploitation Analysis Platform (GREAN).  
151  
The Development and Outlook of Green Hydrogen  
and northwestern China are established respectively with reference to actual conditions. The  
electricity demand is in hours. East-central China and northwestern China show the  
characteristics of double peaks in summer and winter, as shown in Figure 4.4. Typical daily  
load curves in summer and winter are shown in Figure 4.5 and Figure 4.6.  
Figure 4.4 Annual Electricity Load Curve of a Province in Western and East-Central China (Hours)  
Figure 4.5 Typical Daily Electricity Load Curve of a Province in Northwestern China  
Figure 4.6 Typical Daily Electricity Load Curve of a Province in East-Central China  
152  
4
Electricity-Hydrogen Coordinated Zero-carbon Energy System  
The hydrogen demand is in months. With reference to the actual natural gas consumption in  
northwestern and east-central China, the hydrogen demand is formulated, generally showing a  
trend of low in summer and high in winter, as shown in Figure 4.7 and Figure 4.8.  
Figure 4.7 Forecast of Hydrogen Demand of a Province in East-Central China  
Figure 4.8 Forecast of Hydrogen Demand of a Province in Northwestern China  
In terms of selection of power transmission and hydrogen transportation technologies, ±800kV  
DC is used for power transmission, and the 10 billion m3 pipeline is used for hydrogen  
transportation based on factors such as energy demand and transportation distance. The  
technical and economic parameters are consistent with those in the previous section. At  
present, long-distance and large-scale hydrogen transportation pipelines have not been  
specifically applied in projects, and the actual construction cost will vary greatly depending on  
the project conditions. In the report, two cost-sensitive schemes of technology continuation and  
technology progress are established, and the impact of hydrogen transportation technology  
progress on the energy allocation mode of the electricity-hydrogen coordinated energy system  
is analyzed based on different construction costs of hydrogen transportation pipelines. In two  
scenarios, the construction costs of hydrogen transportation pipelines are equivalent to 1.5  
times and 1 time that of the current natural gas pipelines with the same capacity respectively  
153  
The Development and Outlook of Green Hydrogen  
(see Section 4.4 for details). The specific costs are shown in Table 4.1.  
Table 4.1 Costs of Hydrogen Transportation Pipelines in Two Scenarios  
Construction cost of hydrogen  
transportation pipelines (RMB 10,000/km)  
Ratio of the cost to the cost of natural gas  
Schemes  
pipelines with the same capacity  
Technology  
continuation  
2020  
1350  
1.5  
1
Technical progress  
In terms of electricity storage and hydrogen storage technology, by 2060, electrochemical  
batteries are expected to be widely used as energy storage equipment in the power system,  
including lithium-ion batteries, sodium-ion batteries, and flow batteries. The construction cost is  
expected to be reduced to RMB 500-700/kWh, and the charge and discharge efficiency is  
expected to reach about 90%. Hydrogen is stored mainly in the form of high-pressure gaseous  
hydrogen. Based on the pressure vessel with storage pressure of 15-50MPa and the  
corresponding auxiliary equipment, the construction cost is about RMB 500-800/kg hydrogen.  
In terms of electrolytic hydrogen production and hydrogen power generation technology, by  
2060, the high-temperature solid oxide electrolysis cell is expected to become the dominant  
electrolysis cell for hydrogen production, and the cost of the electrolytic hydrogen production  
system is expected to be RMB 1800/kW and the efficiency is expected to reach 90%. For  
hydrogen power generation technology, the combined cycle hydrogen fueled gas turbine is  
mainly considered. The initial investment cost is expected to be RMB 2500/kW and the power  
generation efficiency is expected to reach 60%.  
The expected costs and key technical parameters of various technologies are shown in Table  
4.2 and Table 4.3.  
Table 4.2 Technical Cost Parameters  
Technical cost  
Type  
Wind power  
Initial investment cost  
3200  
1200  
PV power  
Power generation  
(RMB/kW)  
Concentrated solar power  
14,000  
Hydrogen production system by  
water electrolysis  
1800  
Hydrogen-fueled gas turbine  
Electricity storage  
2500  
700  
Energy storage  
(RMB/kWh)  
Hydrogen storage  
60  
Methane storage  
6
Hydrogen transportation  
UHV power transmission  
(See 2.2.2 for details)  
(See 2.2.2 for details)  
transmission  
154  
4
Electricity-Hydrogen Coordinated Zero-carbon Energy System  
Table 4.3 Energy Conversion and Storage Efficiency  
Process Efficiency (%)  
Electrolytic hydrogen production  
Hydrogen generation  
Electricity Storage  
90  
60  
90  
80  
Hydrogen storage  
2. Optimal Calculation Results  
Under the technology continuation scheme, no hydrogen transportation pipeline is required  
between western China and east-central China. All the hydrogen demand in east-central China  
is met by the transmission of power from renewable energy in western China through UHV DC  
transmission channels to east-central China for local hydrogen production. The main reason is  
that there is a large gap between the unit energy costs of hydrogen transportation and power  
transmission. Under the scheme, the levelized cost of energy consumption of the whole system  
is RMB 0.579/kWh. The production, transmission, and consumption of electricity and hydrogen  
are shown in Figure 4.9.  
If the energy transmission scheme of the electricity-hydrogen coordinated system is not  
optimized as a whole, and the power transmission and hydrogen transportation are only used  
to meet the electricity and hydrogen demands of the energy consumption center respectively,  
the comprehensive energy consumption cost of the whole system will increase significantly to  
RMB 0.596/kWh, as shown in Figure 4.10.  
Figure 4.9 Production, Transmission, and Consumption of Electricity and  
Hydrogen Under the Technology Continuation Scheme  
155  
The Development and Outlook of Green Hydrogen  
Figure 4.10 Separate Transmission of Power and Hydrogen Under the  
Technology Continuation Scheme  
Under the technology progress scheme, there are both power transmission channels and  
hydrogen transportation pipelines between western China and east-central China. The  
capacity of hydrogen transportation pipelines is 1.69 billion m3/a, the actual hydrogen  
transportation capacity is 1.60 billion m3/a, and the utilization rate is nearly 100%. 85% of the  
hydrogen demand in east-central China is met by the transmission of power through UHV DC  
transmission channels to east-central China for local hydrogen production, and 15% is met by  
the transportation of hydrogen produced in western China to east-central China through  
pipelines. The levelized cost of energy consumption of the whole system is RMB 0.576/kWh.  
The production, transmission, and consumption of electricity and hydrogen are shown in Figure  
4.11.  
Figure 4.11 Production, Transmission, and Consumption of Electricity and  
Hydrogen Under the Technology Progress Scheme  
156  
4
Electricity-Hydrogen Coordinated Zero-carbon Energy System  
Under the scheme, the levelized costs of power transmission and hydrogen transportation are  
RMB 0.061/kWh and RMB 0.084/kWh (equivalent to RMB 0.307/m3) respectively. It can be seen  
that although the levelized cost of hydrogen transportation is still higher than that of power  
transmission, the hydrogen transportation pipeline plays a systematic role and reduces the  
overall energy consumption cost. This is mainly reflected in the following three aspects: first,  
the utilization efficiency of hydrogen production equipment in western China is greatly  
improved and the overall hydrogen production cost of the system is reduced; second, the  
function of hydrogen storage equipment at both ends is fully exerted, and the demand for  
electricity storage is reduced; third, the utilization efficiency of renewable energy is improved  
and the overall installed capacity of electricity sources is reduced.  
To sum up, when the construction cost of hydrogen transportation pipelines is high (it will still  
be 1.5 times that of the current natural gas pipelines by 2050), the levelized cost of hydrogen  
transportation is significantly higher than that of power transmission. Therefore, it is more  
cost-effective for the energy consumption center to obtain the electricity transmitted from the  
clean energy bases for local hydrogen production to meet the local demand. When the  
construction cost of hydrogen transportation pipelines drops to the expected level in 2050, that  
is, it is equivalent to the cost of natural gas pipelines, although the levelized cost of hydrogen  
transportation is still higher than that of power transmission, the systematic value of  
electricity-hydrogen coordination is reflected due to the improvement of the flexible adjustment  
capability of the system and the utilization rate of renewable energy, and the overall energy  
consumption cost of the system is reduced compared with that of power transmission only. If  
the construction cost of hydrogen transportation pipelines can be further reduced, the  
hydrogen demand in eastern China will be more met by direct hydrogen transportation, and the  
system cost will be further reduced. The comparison of total investment costs of the two  
schemes is shown in Table 4.4.  
Table 4.4 Comparison of Investment Costs of Different Equipment under Two Schemes  
Technology continuation  
scheme  
Technology progress  
scheme  
Equipment  
Wind power  
PV power  
390.9  
196.8  
388.4  
199.5  
Power generation equipment  
(RMB 100 million)  
Concentrated solar  
power  
1258.0  
1255.5  
Electricity storage  
Hydrogen storage  
137.6  
126.1  
137.2  
118.6  
Energy storage equipment  
(RMB 100 million)  
Hydrogen production equipment  
(RMB 100 million)  
Electrolysis bath  
UHV DC  
169.0  
99.5  
172.6  
86.2  
Transmission equipment  
(RMB 100 million)  
Hydrogen  
transportation pipe  
0
5.9  
Total (RMB 100 million)  
2377.9  
0.579  
2363.9  
0.576  
Comprehensive energy  
consumption cost (RMB/kWh)  
157  
The Development and Outlook of Green Hydrogen  
4.2.3 Comparison of Different Scenarios  
The optimization of power transmission and hydrogen transportation of the electricity-hydrogen  
coordinated system in typical large-capacity, long-distance, and inter-regional energy  
transmission scenarios is studied in the previous section. In fact, there are significant  
differences in the transportation distance and scale between energy production and energy  
demand in different scenarios. For example, the transportation distance is about 100-200km  
and the scale of hydrogen transportation is about hundreds of millions or billions of m3 in the  
intercity transportation scenario, the transportation distance is about 1000-3000km and the  
scale of hydrogen transportation can reach 10 billion m3 in the inter-regional transportation  
scenario, and the transportation distance may exceed 5000km and the scale of hydrogen  
transportation can reach more than 100 billion m3 in the international transportation  
scenario. Different transportation scenarios directly determine the selection of power  
transmission and hydrogen transportation technology forms and also affect the  
proportional relationship between the two in the electricity-hydrogen coordinated system.  
Even in the same scenario, the optimal allocation scheme will vary with the transportation  
distance and scale due to the differences in the characteristics of hydrogen transportation and  
power transmission technologies.  
In this section, the optimal allocation relationship between power transmission and hydrogen  
transportation in different transportation scenarios is compared, and the impact of  
transportation distance and scale on the selection of energy transmission technologies is  
studied based on the electricity-hydrogen coordinated system optimization model. The cost of  
various hydrogen transportation technologies is at the scheme level in the previous section.  
The results show that different solutions need to be selected based on the transportation  
distance and scale for hydrogen energy allocation in the electricity-hydrogen zero-carbon  
energy system. The optimal allocation of power transmission and hydrogen transportation in  
various main scenarios is shown in Figure 4.12.  
Figure 4.12 Optimal Allocation Schemes of Green Hydrogen in Different Scenarios  
158  
4
Electricity-Hydrogen Coordinated Zero-carbon Energy System  
When the transportation distance is 100-200km, 500 (330) kV AC is selected for power  
transmission. The tube trailer (high-pressure gaseous hydrogen), liquid hydrogen tank truck,  
and hydrogen transportation pipeline can be selected for hydrogen transportation from small to  
large based on the transportation scale. When the transportation scale is small (less than 5 t/d),  
hydrogen transportation by tube trailers has the advantages of flexible configuration and lower  
total investment compared to power transmission lines and hydrogen transportation pipelines,  
so it is a better choice. When the transportation scale is large, AC is selected for power  
transmission, supplemented by hydrogen transportation through pipelines. If the surplus  
transmission capacity of the existing AC power grid is used, the cost advantage of power  
transmission is more obvious.  
When the transportation distance is 200-1000km, the ±500kV DC is selected for power  
transmission. The liquid hydrogen tank truck and hydrogen transportation pipeline can be  
selected for hydrogen transportation. When the transportation scale is small (less than 10 t/d),  
the liquid hydrogen tank truck can be selected for hydrogen transportation. When the  
transportation scale is large, DC transmission and hydrogen pipeline transportation should be  
adopted simultaneously. As the distance increases, the cost advantage of power transmission  
over hydrogen transportation is also increasing. The main reason is that the investment cost of  
convertor stations at both ends of the DC transmission project is high, and its proportion in the  
total investment will be diluted with the increase of transportation distance, while the investment  
cost of hydrogen pipeline transportation is almost linearly related to the transportation distance,  
so the levelized costs of power transmission and hydrogen transportation will show different  
trends with the change of transportation distance.  
When the transportation distance is 1000-6000km, the power transmission technology can  
select ± 800kV or ± 1100kV UHVDC, and the hydrogen transportation technology should select  
pipelines for hydrogen transportation. With the increase of distance and the LCOE gradually  
apportioned and diluted, the economic advantage of power transmission over hydrogen  
pipeline transportation is improving, and the increase of power transmission proportion helps to  
reduce the overall cost of the system.  
When the transportation distance exceeds 6000km, it is difficult to achieve a single power  
transmission project based on the existing technologies. UHV multi-terminal DC or  
“gird-to-grid” interconnection needs to be adopted to increase the number of convertor  
stations and increase the transportation distance in the form of relays. This increases the cost  
of power transmission projects, and the economic advantages of hydrogen transportation  
through pipelines can be brought into play. If the cross-sea transportation is adopted, the  
construction cost of submarine cables and hydrogen transportation pipelines is much  
higher than that of land, but the shipping cost has little to do with the transportation  
distance. Therefore, the hydrogen will mainly be transmitted by the sea in the form of liquid  
hydrogen or liquid ammonia, and hydrogen storage liquid organic compounds for cross-sea  
transportation.  
159  
The Development and Outlook of Green Hydrogen  
Box 4.1  
Hydrogen Transportation through Natural Gas Pipelines  
In addition to direct hydrogen transportation and power transmission for hydrogen  
production, the hydrogen-enriched compressed natural gas pipeline transportation can  
be used, or the natural gas is transmitted to energy consumption centers for hydrogen  
production through thermal reforming and CCS technology is used to capture and store  
the by-product carbon dioxide (i.e. blue hydrogen), which is also a feasible technical  
route to achieve large-scale and long-distance energy transmission and meet the  
hydrogen demand.  
Taking the West-East Natural Gas Transmission Pipeline II as an example, it is estimated  
that the cost of natural gas is about RMB 3.4/m3 after the natural gas is transmitted to the  
east through pipelines. Natural gas is used for hydrogen production through thermal  
reforming and carbon dioxide is captured and stored. The levelized cost of blue  
hydrogen is about RMB 1.93/m3. The cost of green hydrogen produced in the west by  
using clean energy to generate electricity and transmitted to the east through blending  
hydrogen into the natural gas pipeline is about RMB 1.9/m3. The cost of natural gas  
transmission + blue hydrogen production is equivalent to that of green hydrogen  
production + hydrogen-enriched compressed natural gas pipeline transmission. The  
schematic diagram of the two routes is shown in the figure below.  
Box 4.1 Figure Schematic Diagram of Natural Gas Transmission + Blue Hydrogen  
Production and Green Hydrogen Production + Hydrogen-Enriched  
Compressed Natural Gas Pipeline Transmission  
160  
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Electricity-Hydrogen Coordinated Zero-carbon Energy System  
Before the electricity from clean energy for large-scale hydrogen production is  
economically competitive, hydrogen production by natural gas is combined with CCS  
technology and the electricity from clean energy for hydrogen production is mixed with  
natural gas transmission technology to provide a low-carbon and cost-competitive  
hydrogen supply scheme to meet the hydrogen demand.  
4.3 Study on Allocation of Green Hydrogen in China  
According to the above research results, multiple factors such as traditional electricity demand,  
green hydrogen demand, and renewable energy resources can be considered as a whole, and  
the electricity-hydrogen coordinated allocation scheme with the lowest energy consumption  
cost of the system can be proposed based on the electricity-hydrogen coordinated energy  
system model. In this section, the previous “electricity replacement” scenario is used as a  
control scenario to study the optimal layout and allocation scheme of renewable energy  
development, power flow, and hydrogen transportation through pipelines scale to meet the  
green hydrogen demand in China by 2060, analyze the impact of green hydrogen allocation on  
power planning, and quantify and calculate the comprehensive energy consumption cost of  
the electricity-hydrogen coordinated zero-carbon energy system.  
4.3.1 Control Scenario  
The “electricity replacement” scenario is used as a control scenario in the report. In this  
scenario, the electricity consumption of the whole society is expected to reach 14,000 TWh,  
and the installed capacity of clean energy power generation is expected to exceed 6000GW,  
accounting for 95% by 2060. To meet the flexibility regulation of the system and ensure the  
power supply reliability, the installed capacity of short-term energy storage is 870GW  
(including 180 GW of pumped storage), and the installed capacity of long-term energy storage  
is 23 GWA. An energy allocation platform with the UHV grid as the backbone grid and  
coordinated development of power grids at all levels is formed in China to transform the energy  
allocation mode through the interconnection of large power grids, so as to strengthen the  
connectivity with neighboring countries, promote the large-scale development and  
consumption of clean energy, and accelerate the intelligent interactive development of power  
grids, thus achieving the multi-energy complement and optimal allocation. The country is  
divided into seven regions, including northeastern China, northern China, northwestern China,  
southwestern China, central China, eastern China, and southern China. By 2060, the  
inter-regional and inter-provincial power flow is expected to reach 830 GW, including the  
inter-regional power flow of about 600 GW, forming the energy development pattern of “power  
transmission from West to East, power transmission from North to South, and cross-border  
interconnection”, as shown in Figure 4.13 and Table 4.5.  
AThe continuous discharge time of the short-term energy storage is taken as 6 hours, and the continuous  
discharge time of the long-term energy storage is taken as 720 hours.  
161  
The Development and Outlook of Green Hydrogen  
Figure 4.13 Schematic Diagram of Inter-regional Power Flow in China by 2060  
Table 4.5 Inter-regional Power Flow in China by 2060  
Power flow  
Capacity (10,000kW)  
Power consumption (100GWh)  
①
②
③
④
⑤
⑥
⑦
⑧
⑨
⑩
⑪
⑫
⑬
⑭
1700  
7200  
8900  
2900  
1000  
3800  
8400  
2700  
5780  
3600  
1500  
1600  
6900  
70  
890  
5200  
5100  
2200  
400  
2900  
6900  
1300  
410  
1800  
320  
430  
2700  
20  
162  
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Electricity-Hydrogen Coordinated Zero-carbon Energy System  
4.3.2 Green Hydrogen Allocation Research  
In the “electricity + hydrogen” scenario ( i.e., China Energy Interconnection scenario),  
according to the demand forecast, development potential, and development cost distribution  
of green hydrogen, the overall allocation scheme of green hydrogen in China by 2060 is  
studied based on the electricity-hydrogen coordinated optimal allocation model. By 2060, the  
demand for green hydrogen is expected to be 75 Mt, the electricity demand for hydrogen  
production is expected to be about 3000 TWh based on the efficiency of hydrogen production  
from green electricity of 90%, the total electricity demand of the whole society is expected to  
reach 17,000 TWh, and the electrification rate is expected to reach 66%.  
Based on different ways to meet the demand for green hydrogen, four modes are proposed in  
the report for comparison: local hydrogen production mode, independent hydrogen network  
mode, replacing hydrogen transportation with power transmission mode, and electricity-  
hydrogen coordination mode.  
1. Local hydrogen production mode  
The demand for green hydrogen in seven regions is all met by hydrogen produced locally from  
local green electricity. Based on the situation of clean energy resources, clean energy  
resources with different costs are developed step by step in the local region in the principle of  
development costs from low to high, supported by electrolytic hydrogen production equipment.  
No inter-regional power transmission lines are added, and no new hydrogen transportation  
pipelines are built.  
The results show that compared with the control scenario, the installed capacity of wind power  
and PV power in seven regions is increased by 410 GW and 1330 GW respectively, reaching  
2320 GW and 3820 GW. The short-term energy storage is decreased by 117 GW, and the  
long-term energy storage is decreased by 23.4 GW. The power of electrolytic hydrogen  
production equipment in regions is 940 GW, and the hydrogen storage capacity is 4.6 Mt. The  
total investment in green hydrogen production and allocation infrastructure is about RMB 7.3  
trillion, and the levelized cost of green hydrogen is about RMB 10.9/kg. If the overall system  
benefits after the installed capacity of energy storage is reduced are considered, the cost of  
green hydrogen is RMB 9.4/kg.  
2. Independent hydrogen network mode  
Based on the local hydrogen production from green electricity, the layout of hydrogen  
production resources is optimized depending on the comprehensive “hydrogen production +  
hydrogen transportation” cost in eastern and central China. The green hydrogen produced in  
western China and needed to be consumed in eastern China is all allocated by hydrogen  
transportation through pipelines. The capacity of new clean energy electricity sources,  
hydrogen production equipment, and hydrogen transportation pipelines required in regions is  
determined based on the optimal calculation results of the model.  
The results show that compared with the control scenario, the installed capacity of wind power  
and PV power in seven regions is increased by 500 GW and 820 GW respectively, reaching  
163  
The Development and Outlook of Green Hydrogen  
2410 GW and 3310 GW. The short-term energy storage is decreased by 115 GW, and the  
long-term energy storage is decreased by 23.4 GW. The power of electrolytic hydrogen  
production equipment in regions is 840 GW, and the hydrogen storage capacity is 4.8 Mt. To  
meet the demand of wide-area allocation of green hydrogen, four new hydrogen transportation  
pipelines including Northwestern China-Central China, Northwestern China-Eastern China,  
Southwestern China-Southern China, and Southwestern China-Central China are built, with a  
total transportation capacity of 173 billion m3 and an annual hydrogen transportation of about  
161 billion m3 (about 585,000 GWh ). The total investment in green hydrogen production and  
allocation infrastructure is about RMB 7 trillion, and the levelized cost of green hydrogen is  
about RMB 10.6/kg. If the overall system benefits after the installed capacity of energy storage  
is reduced are considered, the cost of green hydrogen is RMB 9.1/kg.  
3. Replacing hydrogen transportation with power transmission mode  
Based on the local hydrogen production from green electricity in eastern and central China, the  
insufficient green hydrogen is produced locally from green electricity transmitted from western  
China with better clean energy resources through UHV transmission channels. The capacity of  
new clean energy electricity sources, hydrogen production equipment, and transmission  
channels required in regions is determined based on the optimal calculation results of the model.  
The results show that compared with the control scenario, the installed capacity of wind power  
and PV power in seven regions is increased by 500 GW and 990 GW respectively, reaching  
2410 GW and 3480 GW. The short-term energy storage is decreased by 140 GW, and the  
long-term energy storage is decreased by 23.4 GW. The power of electrolytic hydrogen  
production equipment in regions is 850 GW, and the hydrogen storage capacity is 1.71 Mt. To  
meet the demand of wide-area allocation of green hydrogen, the new capacity of transmission  
channels is 130 GW, and the annual new inter-regional power transmission is 1200 TWh. The  
total investment in green hydrogen production and allocation infrastructure is about RMB 6.3  
trillion, and the levelized cost of green hydrogen is about RMB 9.5/kg. If the overall system  
benefits after the installed capacity of energy storage is reduced are considered, the cost of  
green hydrogen is RMB 7.7/kg.  
4. Electricity-hydrogen coordination mode  
Based on the local hydrogen production from green electricity in eastern and central China,  
direct hydrogen transportation or replacing hydrogen transportation with electricity  
transportation can be used for insufficient green hydrogen in the principle of optimal economic  
combination. The capacity of new clean energy electricity sources, hydrogen production  
equipment and transportation channels and hydrogen transportation pipelines required in  
regions are determined based on the optimal calculation results of the model.  
The results show that compared with the control scenario, the installed capacity of wind power  
and PV power in seven regions is increased by 480 GW and 820 GW respectively, reaching  
2390 GW and 3310 GW. The short-term energy storage is decreased by 140 GW, and the  
long-term energy storage is decreased by 23.4 million kilowatts. The power of electrolytic  
hydrogen production equipment in regions is 840 GW, and the hydrogen storage capacity is  
1.75 Mt. To meet the demand of wide-area allocation of green hydrogen, the new capacity of  
164  
4
Electricity-Hydrogen Coordinated Zero-carbon Energy System  
transmission channels is 90 GW, and the annual new inter-regional power transmission is 1100  
TWh (including the power transmission of new channels of 710 TWh). Three new hydrogen  
transportation pipelines including Northwestern China-Central China, Southwestern  
China-Southern China, and Northwestern China-Eastern China are built, with a total  
transportation capacity of about 100 billion m3 and an annual hydrogen transportation of about  
85 billion m3 (about 310 TWh). The total investment in green hydrogen production and  
allocation infrastructure is about RMB 6.2 trillion, and the levelized cost of green hydrogen is  
about RMB 9.3/kg. If the benefits after the installed capacity of energy storage is reduced are  
considered, the cost of green hydrogen is RMB 7.6/kg. See Table 4.6 for specific data.  
Table 4.6 Comparison of Optimal Results of Four Modes  
“Electricity + hydrogen” scenario  
Replacing  
Control  
Local  
Independent hydrogen Electricity-  
Item  
scenario  
hydrogen hydrogen transportati- hydrogen  
production  
network on with powercoordination  
transmission  
Wind power (100 GW)  
19.1  
2462  
24.9  
1498  
23.2  
2567  
38.2  
1384  
24.1  
2617  
33.1  
1483  
24.1  
2608  
34.8  
1463  
23.9  
2624  
33.1  
1489  
Full-load hours  
PV power (100 GW)  
Full-load hours  
Renewable energy  
installed capacity  
Short-term energy storage  
(including pumped  
storage)  
Energy storage  
installed capacity  
(100 GW)  
8.74  
7.58  
7.60  
7.35  
7.35  
Long-term energy storage  
0.23  
—
0
0
0
0
Equipment Capacity  
(100 GW)  
Hydrogen  
production  
equipment  
9.4  
8.4  
8.5  
8.4  
Full-load hours  
—
2836  
460  
3171  
540  
3116  
170  
3176  
175  
Capacity of hydrogen storage  
equipment (10,000 t)  
—
Inter-regional transmission  
5.6  
—
5.6  
—
5.6  
—
6.9  
1.3  
6.5  
capacity（100 GW)  
New transmission  
capacity (0.1 GW)  
0.93  
6553  
Full-load hours of  
transmission channel  
5480  
6298  
6359  
6555  
Transmission  
channel  
Transportation capacity of  
hydrogen network (100  
million cubic meters)  
—
—
—
—
1730  
93%  
—
—
1000  
85%  
Utilization rate of  
hydrogen transportation  
pipeline  
Investment in green hydrogen infrastructure  
(RMB 100 million)  
—
—
72,590  
10.93  
70,140  
10.56  
62,950  
9.48  
61,880  
9.32  
Levelized cost of green hydrogen (RMB/kg)  
165  
The Development and Outlook of Green Hydrogen  
In summary, the four allocation schemes, compared with the control scenario, give full play to  
the role of hydrogen production equipment as the flexible adjustable load to effectively improve  
the utilization efficiency of wind power and PV power generation equipment and transmission  
equipment, thus reducing the demand for energy storage in the power system. Among these  
four schemes, the electricity-hydrogen coordinated allocation scheme better exerts the  
connection relationship of development from the same sources, complementary applications,  
and easy conversion between green electricity and green hydrogen, makes full use of power  
system facilities, and has the lowest investment in hydrogen production, hydrogen storage and  
hydrogen transportation infrastructure and the lowest levelized cost of green hydrogen.  
Specifically, compared with the control scenario, 55% of the new installed capacity of wind  
power and PV power is distributed in the inbound ends such as northern China, eastern China,  
central China, and southern China for directly generating electricity locally for hydrogen  
production, and 45% of the new installed capacity is distributed in outbound ends such as  
northwestern China, southwestern China, and northeastern China, and green hydrogen is  
transmitted to central and eastern China by the hydrogen transportation through pipelines or  
“replacing hydrogen transportation with power transmission” on the basis of meeting the local  
demand for hydrogen in the electricity-hydrogen coordinated allocation mode. The capacity of  
new transmission channels is about 93 GW, which is equivalent to that of 10-12 new ±800kV UHV  
DC transmission projects. Three new hydrogen transportation pipelines are built, with the annual  
transportation capacity of Northwestern China-Central China pipeline of 45 billion m3, Southwestern  
China-Southern China pipeline of 29 billion m3, and Northwestern China-Eastern China pipeline  
of 26 billion m3. The hydrogen energy allocation is shown in Figure 4.14 and Table 4.7.  
Figure 4.14 Schematic Diagram of Inter-regional Hydrogen Allocation of China in 2060  
166  
4
Electricity-Hydrogen Coordinated Zero-carbon Energy System  
In general, the total utilization of renewable energy to generate hydrogen on-site in each region  
is 40 Mt, and the total amount of inter-regional hydrogen transportation is 35 Mt (accounting for  
45% of the total demand), of which 7.8 Mt of hydrogen transmitted directly by pipelines and  
1100TWh of hydrogen is transmitted by power transmission (equivalent to 27 Mt of hydrogen,  
accounting for about 75% of the total transportation).  
Table 4.7 Added Inter-regional Power Flow and Hydrogen Flow of China in 2060  
New capacity  
(10,000kW)  
Added electricity  
(100GWh)  
Power flow  
①
②
③
⑤
⑥
⑨
⑩
⑪
⑫
⑬
⑭
3400  
3000  
600  
1700  
250  
4500  
1800  
550  
220  
150  
350  
10  
0
0
0
5800  
0
0
0
0
0
0
Hydrogen transport capacity  
(10,000 tons)  
Converted electricity  
(100GWh)  
Hydrogen Flow  
①
②
③
240  
400  
140  
1050  
1800  
620  
4.3.3 Electricity-hydrogen Coordinated Zero-carbon Energy System  
The electricity-hydrogen coordinated optimal allocation closely couples electricity and  
hydrogen energy forms, forming an electricity-hydrogen coordinated zero-carbon energy  
system. The electricity-hydrogen coordinated zero-carbon energy system takes wind, solar  
and other renewable energy as the main energy supply, converts renewable energy into  
energy varieties such as electricity and hydrogen that can be directly used through  
technologies such as generation and electrolytic hydrogen production, and then delivers  
energy to the energy-using center through technologies such as power transmission and  
hydrogen transportation, supplemented by electricity storage and hydrogen storage to meet  
167  
The Development and Outlook of Green Hydrogen  
the demands of end-use electricity and hydrogen. Electricity-hydrogen coordinated allocation  
can improve the utilization efficiency of wind energy, solar energy, and other renewable energy  
at the energy development side; At the energy storage side, it provides a low-cost flexible  
regulation resource for the system to reduce the system’s demands for energy storage  
equipment; At the transmission side, it reduces the infrastructure investment and improves the  
utilization efficiency of power transmission and hydrogen transportation equipment; At the  
energy consumption side, it meets different energy demands and reduces the overall energy  
consumption cost.  
According to the calculation results, compared with the control scenario without demand of  
green hydrogen, the national rate of wind and PV curtailment has dropped from 9.6% to 4%.  
Given that the widespread application of electrolytic hydrogen production equipment can  
replace short-term energy storage of about 140GW and long-term energy storage of 23.4  
million kilowatts, the full-load hours of transmission channels have been increased from 5500 to  
6500, and the utilization rate of pipelines for hydrogen transportation can reach about 85%.  
Compared with the on-site hydrogen production mode, the total investment of energy system is  
expected to save RMB 1 trillion, and the levelized cost of green hydrogen can be reduced by  
about 15%. The electricity-hydrogen coordinated allocation of China in 2060 is shown in Figure  
4.15 and Table 4.8.  
Figure 4.15 Schematic Diagram of Electricity-Hydrogen  
Coordinated Allocation of China in 2060  
168  
4
Electricity-Hydrogen Coordinated Zero-carbon Energy System  
Table 4.8 Results of Electricity-Hydrogen Coordinated Allocation of China in 2060  
Power flow  
Capacity (10,000kW)  
Power consumption (100GWh)  
①
②
③
④
⑤
⑥
⑦
⑧
⑨
⑩
⑪
⑬
⑬
⑭
5100  
7200  
8900  
2900  
1000  
9600  
8400  
2700  
5780  
3600  
1500  
1600  
6900  
70  
3900  
5800  
6800  
2200  
650  
7400  
6900  
1300  
2200  
2350  
540  
570  
3050  
30  
Hydrogen transport capacity  
(10,000 tons)  
Converted electricity  
(100GWh)  
Hydrogen Flow  
①
②
③
240  
400  
140  
1050  
1800  
620  
The electricity-hydrogen coordinated zero-carbon energy system gives full play to the  
advantages of easy large-scale storage of hydrogen and easy transmission of power. Because  
of the fluctuation and intermittence of new energy sources, a new type of power system with  
renewable energy sources as the main body needs to configure a large amount of energy  
storage to solve the imbalance between power supply and demand. Common energy storage  
methods in power systems mainly include pumped storage and electro-chemical storage. The  
site resources for pumped storage are limited and the cost of electro-chemical storage is  
relatively high, and the energy storage capacity of both is limited, which should not be used for  
long-term energy storage, and it is difficult to solve the problem of electricity imbalance across  
seasonsA. Hydrogen is a substance with an entity, which is easier to achieve long-term and  
AGlobal Energy Interconnection Development and Cooperation Organization (GEIDCO), The Development  
169  
The Development and Outlook of Green Hydrogen  
large-capacity storage when compared with electricity. However, those direct hydrogen  
transportation methods have the disadvantages of low transmission energy density, slow  
speed, and high cost. The electricity-hydrogen coordinated allocation not only gives full play to  
the buffering effect of hydrogen energy on the contradiction between supply and demand of  
power system, but also applies mature and economical transportation technology to transmit  
the hydrogen, which is of great significance for the clean transformation of the energy system  
and the carbon neutrality of the whole society.  
4.4 Comprehensive Values  
4.4.1 Value of Flexibility  
Green electricity and green hydrogen are coupled with each other, and it significantly improves  
the flexibility of the energy system. On a short time scale (hours to days), electrolytic hydrogen  
production is a kind of flexible load, which can complement the traditional electricity load,  
reduce the peak-valley difference, and better match with the fluctuating new energy generation.  
Therefore, it significantly improves the utilization rate of new energy. Take Northwest China and  
East China as an example: At the sending end, the load of electrolytic hydrogen production  
changes in the same direction as the output of new energy. Under the maximum output of  
renewable energy, the electricity consumption for hydrogen production increases significantly,  
which promotes the consumption of new energy; at the receiving end, the load of electrolytic  
hydrogen production changes in the reverse direction with the net loadA, which reduces the  
fluctuation of the system. The typical weekly electricity balance of Northwest China and East  
China is shown in Figure 4.16.  
Figure 4.16 The Typical Weekly Electricity Balance of  
Northwest China and East China (1)  
Roadmap of Large-scale Energy Storage Technology, 2020.  
AThe net load refers to the net value of electricity load minus the output of uncontrollable renewable energy  
such as wind power and PV.  
170  
4
Electricity-Hydrogen Coordinated Zero-carbon Energy System  
Figure 4.16 The Typical Weekly Electricity Balance of  
Northwest China and East China (2)  
From the quantitative calculation results, by 2060, due to the development of the green  
hydrogen industry, the short-term energy storage demand of power systems can be reduced  
by about 115-140 GW, and the short-term flexible resource investment of the system can be  
saved by about RMB 740-890 billion.  
On a long-term scale (months, quarters), large-scale inter-seasonal storage of new energy  
sources such as wind and solar energy can be realized with the help of the hydrogen  
storage equipment capacity required by the green hydrogen industry chain itself, and the  
seasonal fluctuation of a high proportion of new energy power systems can be effectively  
suppressed. From a national perspective, in spring, new energy is under the maximum  
output, but the traditional electricity load level is low; and the surplus electricity produces  
green hydrogen and stores it, effectively reducing the wind and PV curtailment. In summer,  
the electricity load increases, the new energy generation mainly meets the electricity  
demand, the green hydrogen production decreases moderately, and the stored green  
hydrogen is gradually put into the market to meet the hydrogen consumption demand. In  
summer and winter, two peak periods of electricity consumption, a part of the stored green  
hydrogen can be used in the generation according to the balance requirements of power  
systems, further improving the real-time power balance capability of the system. Changes  
in Electricity Balance and Storage of Hydrogen in China throughout the year are shown in  
Figure 4.17.  
From the quantitative calculation results, by 2060, the hydrogen storage capacity of the green  
hydrogen industry can be fully utilized, which can reduce the long-term energy storage  
demand of the power system by 23.4 million kilowatts and save the long-term flexibility  
resource investment of the system by about RMB 250 billion.  
171  
The Development and Outlook of Green Hydrogen  
Figure 4.17 Changes in Electricity Balance and Storage of  
Hydrogen in China Throughout the Year  
4.4.2 Guarantee Value of Electricity Supply  
Hydrogen can be stored in large capacity in various ways: gas, liquid, compound. Taking  
advantage of the characteristics of bi-directional conversion between electricity and hydrogen,  
it can not only be used as a flexible load to provide the regulation capability for the system, but  
also provide electricity sources support for the system through hydrogen generation  
equipment if necessary. Therefore, it effectively improves the toughness of the power grid on  
both sides of source and load. Especially when the power system encounters the weather  
without wind or light for several consecutive days, hydrogen generation can effectively improve  
the capability to ensure the safety of the power supply.  
Affected by extreme weather, increased electricity load and insufficient power supply  
capacity of the system have been frequently reported at home and abroad. When new  
energy sources such as wind and solar energy become the main electricity sources,  
weather conditions such as extreme heat without wind, extreme cold without light,  
long-term without wind or rain will have an increasing impact on the system. Different kinds  
of meteorological conditions can not only increase the demand for electricity through  
air-conditioning and electric heating equipment but also have the risk of electricity sources  
with a significant decrease in the output of electricity sources or even no electricity  
available. Using the two-way electricity- hydrogen exchange, the hydrogen fueled gas  
turbine and fuel cell is at the source side, and the electrolytic hydrogen production  
equipment is at the load side, so as to adjust the power balance in two directions and  
ensure the balance of power supply and demand.  
Take East China as an example, the wind speed and light intensity in the rainy season are  
172  
4
Electricity-Hydrogen Coordinated Zero-carbon Energy System  
generally small. According to the statistics of 40-year (1980—2020) historical monitoring data  
from 35 local meteorological stations, the situation that the daily wind and PV output are  
extremely low (the wind power output is less than 10% for 20 consecutive hours, and the daily  
cumulative PV energy is less than 20% of the local sunny days) occurs 371 times. The situation  
that the wind and PV output are extremely low for three consecutive days occurs 62 times, that  
is, this situation may occur more than 1.5 times a year. In the 40-year monitoring data, the  
maximum number of continuous days of weather conditions with extremely low wind and PV  
output in East China is 10 days, which occurs once in total. The statistical results of continuous  
days of weather conditions with extremely low wind and PV output in 40-year monitoring data of  
East China are shown in Figure 4.18.  
Figure 4.18 Statistical Results of Continuous Days of Weather Conditions  
with Extremely Low Wind and PV Output of East China  
According to the model, in the electricity sources structure of the system in 2060, if such  
continuous days of rainy and windless weather conditions occur, especially when there is  
no PV output at night, the demand for electricity cannot be met even if hydropower, nuclear  
power, natural gas, biomass, and other adjustable electricity sources are fully operated. On  
the one hand, at the load side, all the electrolytic hydrogen production equipment is shut  
down to reduce the demand for electricity; On the other hand, hydrogen generation  
equipment (including hydrogen-fueled gas turbines and fuel cells) started to participate in  
the power supply of the power grid, with the maximum output reaching 70 million kilowatts  
of rated power, supplementing the electricity lack of the system, and at the same time  
cooperating with new types of energy storage to meet the short-term (4-6 hours) peak  
power supply. When the wind and PV output are restored, the hydrogen generation  
equipment will shut down, and the electrolytic hydrogen production will be resumed. The  
electricity balance of East China in the situation of continuous days of rainy and windless  
weather is shown in Figure 4.19, and the corresponding power changes of wind, light, and  
hydrogen (hydrogen generation is positive and hydrogen production is negative) are  
shown in Figure 4.20.  
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The Development and Outlook of Green Hydrogen  
Figure 4.19 Electricity Balance in Extreme Weather of East China Power Grid  
Figure 4.20 Power Changes of Wind, PV, and Hydrogen in  
Extreme Weather of East China Power Grid  
4.4.3 Value of System Security  
With the continuous deepening of energy transition, the “three highs” characteristics of the  
power system become more and more obvious: high proportion of new energy generation,  
high degree of power electronization, and high proportion of power sending and receiving.  
There are various stability problems, which put forward higher requirements for the safe  
operation of the power system. In terms of synchronization stability, it is difficult for new energy  
to access the AC system with weak voltage support and insufficient short-circuit ratio to realize  
the phase-locked synchronization; Large-capacity DC fault impacts weak AC section, resulting  
in the problem of synchronization stability. In terms of voltage stability, the voltage regulation  
capacity of new energy is weak, and it is difficult to achieve voltage control in large-scale new  
energy grid-connected areas; the dynamic reactive power support capacity and system  
voltage regulation capacity in high proportion power receiving areas are insufficient, and there  
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Electricity-Hydrogen Coordinated Zero-carbon Energy System  
is a risk of voltage instability. In terms of frequency stability, the high-voltage and low-voltage  
ride-through capability of new energy units is insufficient. In case of system failure, a large  
number of interlocking disconnections may be caused, the impact of failure increases, and the  
system security faces the risk of frequency instability. In addition, the multi-time scale response  
characteristics of power electronic devices bring new stability problems such as broadband  
oscillation. The above problems are particularly obvious in central and eastern regions where  
the demand for electricity is large and the proportion of electricity received is high. As  
coal-fired thermal power units are gradually replaced by new energy, there are fewer and fewer  
local supporting electricity sources, and the local power grid is gradually “hollowing”.  
The hydrogen fueled gas turbine is a kind of synchronous generator, which can effectively  
improve the rotational inertia and dynamic reactive power support capacity of the system. The  
layout of hydrogen fueled gas turbines in central and eastern regions can be used as one of  
the important means to prevent the “hollowing” of the power grid at the receiving end, which  
is of great significance to the security and stability of the system. Take a certain region in  
central and eastern regions as an example: When the proportion of new energy is relatively  
high and there are few local supporting electricity sources, the transient voltage stability  
level of the system is insufficient. Under major faults, the recovery after the voltage dip is  
slow or difficult. If there is a DC feeding point in the near region, it may lead to continuous  
commutation failure of DC and absorb a large amount of reactive power, which will further  
worsen the transient voltage level. However, when a certain number of hydrogen fueled gas  
turbines are configured, the voltage can be quickly restored to the normal level after the  
voltage dip under major faults, and the stability of the system is significantly improved. As  
shown in Figure 4.21.  
Figure 4.21 Comparison of Voltage Recovery Curves after AC Fault in a  
Certain Place of Central and Eastern Regions  
4.4.4 Value of Emission Reduction  
The electricity-hydrogen coordinated zero-carbon energy system creates conditions for the  
exploitation and application of green hydrogen, which will promote deep decarbonization  
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The Development and Outlook of Green Hydrogen  
throughout society. Compared with the electricity replacement only, the electricity + hydrogen  
energy realizes the collaborative optimization of electricity and hydrogen. Green hydrogen  
plays a key role between clean energy and end-use energy fields that are difficult to use  
electricity directly, and it promotes the deep decarbonization of non-electricity fields such as  
chemical industry and metallurgy. Green hydrogen will play the role of “last mile” in the process  
of carbon neutrality throughout society. It is estimated that by 2050, the demand for green  
hydrogen will reach 61Mt, the application of green hydrogen in the end-use energy fields can  
reduce the consumption of fossil fuels such as coal, oil, and gas by 270 Mtce and reduce the  
carbon emissions by 510 Mt, which is equivalent to about 20% of the carbon emissions from  
energy activities. By 2060, the demand for green hydrogen reaches 75 Mt, the application of  
green hydrogen in the final energy consumption fields can reduce the consumption of fossil  
fuels by 390 Mtce and reduce the carbon emissions by 620 Mt, which is equivalent to about  
40% of the carbon emissions from energy activities.  
4.5 Hydrogen Power Generation and Green Energy Center  
Coal-fired electricity is one of the major sources of carbon emissions in the energy industry. By  
the end of 2020, China’s coal-fired electricity installed capacity and the volume of power  
generation accounted for 49% and 61% of the total installed capacity of electricity sources and  
power generation respectively, emitting about 40% of carbon dioxide, 15% of SO2, 10% of  
nitrogen oxides and a large number of pollutants such as soot, dust, slag and fly ash. With the  
need for low-carbon development and the deepening of energy transition, the out of service  
and transformation of coal-fired power plants are imminent.  
Electric-hydrogen coordinated urban green energy center is an optional technical path for  
zero-carbon clean transformation of coal-fired electricity in central and eastern regions. The  
joint optimal allocation of two energy carriers can be realized by Electricity-hydrogen  
coordinated optimization. In the future, the green energy center, which provides electricity and  
hydrogen at the same time, will gradually replace the power plant as the main infrastructure of  
local energy supply in energy-using centers in eastern and central regions. With the continuous  
promotion of carbon neutrality throughout society, the coal-fired power plants around the cities  
and urban areas will gradually decrease. These coal-fired power plants will be transformed into  
a green energy center integrating hydrogen production, hydrogen storage, hydrogen power  
generation, hydrogen distribution, and power distribution, which can make full use of the  
original land occupation and power grid access facilities, and become a specific way for the  
implementation of the concept of electricity-hydrogen coordinated allocation at a minimum cost.  
The transformed urban green energy center can provide long-term (monthly) regulation and  
guarantee capabilities for the power system, and it is a strategic supporting electricity source  
for the energy consumption center to deal with special situations such as extreme weather after  
coal-fired electricity is out of service.  
Take a coal-fired power plant with an installed capacity of 2400MW and an occupied area of  
500mu (1mu=666.67m2) in Anhui Province as an example. The original land of the coal-fired  
power plant is transformed into an urban green energy center integrating hydrogen production,  
hydrogen storage, hydrogen power generation, hydrogen distribution, and power distribution  
according to the local demand for hydrogen and electricity, which is mainly divided into three  
modules: hydrogen production, hydrogen storage, and hydrogen power generation. The  
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Electricity-Hydrogen Coordinated Zero-carbon Energy System  
hydrogen production module is equipped with 440 sets of electrolysis cells of 1000 standard  
m3 hydrogen/hour (each with a power of 5MW) and corresponding hydrogen purification  
devices, with a total installed capacity of 2200MW. The hydrogen production system applies  
external clean electricity to produce hydrogen, covering an area of 60 mu with an investment of  
RMB 4.4 billion. The hydrogen storage module is equipped with 30,000 tons of hydrogen  
storage devices, accounting for 20% of hydrogen output. The hydrogen storage equipment  
applies high-pressure gas hydrogen storage tanks with a total tank capacity of 1 million m3.  
Underground salt caverns can also be used to construct large-scale gas hydrogen storage  
caverns in areas where geological conditions permit. The hydrogen storage system mainly  
meets the demand of the hydrogen supply chain and provides a continuous full-power  
generation capacity of 300 hours, covering an area of 80 mu with an investment of RMB 7.5  
billion. The hydrogen power generation module is equipped with 4×600MW hydrogen fueled  
gas turbine generators, which have the same generation capacity as the original coal-fired  
power plant and provide a flexible adjustment capability equivalent to 1.5 times that of the  
original coal-fired power units. The hydrogen power generation system covers an area of 360  
mu with an investment of RMB 7.2 billion. Hydrogen is transmitted among modules through  
low-pressure (4MPa) hydrogen pipelines. The above three modules of hydrogen production,  
hydrogen storage, and hydrogen power generation cover a total area of 500 mu, that is, the  
transition and transformation of the original coal-fired power plant to the urban green energy  
center can be realized without additional occupation. The transformed green energy center  
has the same generation capacity and hydrogen supply capacity of 150,000 t/a, which can  
meet the local hydrogen demand and peak load regulation demand of the power grid, with a  
total investment of about RMB 19 billion. The schematic diagram of the urban green energy  
center is shown in Figure 4.22.  
Figure 4.22 Schematic Diagram of Urban Green Energy Center  
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The Development and Outlook of Green Hydrogen  
Compared with the original coal-fired power plant, the green energy center needs to pay close  
attention to technical problems such as NOx emission, space, hydrogen transportation through  
pipelines, and hydrogen safety during the transformation.  
In terms of NOx emission: Due to the high flame temperature of hydrogen, a pure hydrogen  
fueled gas turbine may lead to higher NOx emission, and tail gas treatment devices are  
required.  
In terms of space: The hydrogen storage module provides a buffer for the system, which is  
necessary to prevent the supply interruption of hydrogen and ensure the continuous operation  
of the system. As a safety area is required around the hydrogen storage tank, it will affect the  
general layout of the power plant and additional space is needed. In addition, due to the  
relatively low volume energy density of hydrogen fueled gas (one-third of that of natural gas),  
large-diameter pipelines are required to adapt to higher volume flow and prevent hydrogen  
embrittlement.  
In terms of hydrogen transportation through pipelines: Problems such as hydrogen  
embrittlement are generally not caused by low-pressure hydrogen transportation. However,  
under high-temperature conditions, if hydrogen needs to be preheated to improve its  
performance, it may lead to hydrogen molecule leakage, which requires the adoption of new  
fuel auxiliary pipelines and valves to solve hydrogen embrittlement, hydrogen leakage, and  
other problems.  
In terms of hydrogen safety: Although there have been decades of experience in using  
hydrogen in industry and applying large dedicated distribution pipelines for hydrogen  
transportation, there is no relevant operating hydrogen standard for hydrogen-fired  
turbines at present. Hydrogen molecules are so small that can easily diffuse into  
conventional steel materials, increasing the risk of failure; compared with large molecules  
such as natural gas, small-sized hydrogen molecules are easier to escape through  
sealing and connecting parts. In addition, the luminosity of hydrogen flame is very low,  
which is difficult to be perceived by human eyes. These characteristics of hydrogen  
require strict safety measures, such as improving sealing and connecting parts,  
configuring a special flame detector system for hydrogen flame, and improving the  
ventilation system.  
4.6 Summary  
The reverse distribution of clean energy production and consumption objectively requires  
long-distance and large-scale transportation of green hydrogen. The western region is rich in  
renewable energy, and the preparation cost of green hydrogen is about 50% of that of the  
eastern and central regions. Therefore, solving the transportation problem of green hydrogen is  
a significant foundation for promoting the wide application of green hydrogen and the  
realization of carbon neutrality throughout society.  
In the case of long-distance and large-scale transportation, replacing hydrogen transportation with  
power transmission is more economical. According to the existing technical level, the  
pipeline with a designed capacity of 12 billion m3/year (2000km) is used to transport  
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Electricity-Hydrogen Coordinated Zero-carbon Energy System  
hydrogen, and the cost is about RMB 0.35/m3 (the unit energy transmission cost is about  
RMB 0.096/kWh). The UHV power transmission technology is mature and economically  
competitive, and it has been widely used on a large scale. The unit transmission cost is  
only about RMB 0.06/kWh. The UHV power transmission technology is used to transmit the  
electricity produced by the clean energy base to the areas around the hydrogen  
consumption center for on-site hydrogen production, which is more economical than direct  
hydrogen transportation.  
Constructing an electricity-hydrogen coordinated zero-carbon energy system can realize the  
optimal allocation of green hydrogen. Green hydrogen comes from green electricity and can  
be converted into each other easily. The combination of direct hydrogen transportation and  
replacing hydrogen transportation with power transmission can give full play to the advantages  
of mature power transmission technology and high economic efficiency, and the large-scale  
and long-term energy storage function of hydrogen storage, improve the utilization efficiency  
of new energy generation, transmission and hydrogen production equipment, and reduce  
the overall investment of energy system. By 2030, the total amount of inter-regional  
hydrogen transportation between the western region and the eastern and central regions is  
expected to be 1 Mt, and the mode of replacing hydrogen transportation with power  
transmission (5000GWh) will be used. By 2060, the total amount of inter-regional hydrogen  
transportation between regions is expected to be 35 Mt (about 45% of the total demand),  
including about 7.8 Mt of hydrogen transmitted directly by pipelines. The electricity  
transmitted by replacing hydrogen transportation with power transmission is expected to  
be 1100 TWh (equivalent to 27 Mt of hydrogen, accounting for more than 75% of the total  
transportation capacity). At the same time, compared with the single energy transmission  
mode, diversified energy transmission modes can improve the flexibility, reliability, and risk  
resistance capability of energy allocation, and effectively control the security risks of energy  
systems.  
To achieve the electricity-hydrogen coordinated allocation, the technology of hydrogen  
transportation through pipelines needs to be further developed. According to the calculation  
results, the cost of hydrogen transportation through pipelines is so high at the current level of  
technology that the cost of direct popularization and application will be higher than the  
systematic benefit of electricity-hydrogen coordinated allocation. As the cost of hydrogen  
transportation through pipelines is equivalent to the current cost of natural gas pipelines, it is  
helpful to reduce the comprehensive energy consumption cost of the electricity-hydrogen  
zero-carbon energy system by forming an energy allocation in which replacing hydrogen  
transportation with power transmission, supplemented by hydrogen transportation through  
pipelines. At present, China has limited experience in the construction and operation of the  
dedicated hydrogen pipeline network, and it is difficult to form technical and economic  
competitive advantages, compared with mature UHV power transmission technology. However,  
given the long-term configuration requirements of the electric-hydrogen coordinated system in  
the future, it is necessary to carry out the construction of long-distance and large-capacity pure  
hydrogen pipeline demonstration project as soon as possible, improve the technical level and  
maturity of the project, reduce the project cost, and form a pattern of combining allocation of  
green hydrogen for on-site preparation and utilization with large-scale optimization across the  
country at an early date.  
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Conclusion and Prospect  
Conclusion and  
Prospect  
The Development and Outlook of Green Hydrogen  
Green hydrogen and green power are developed from the same source with  
complementary applications and coordinated allocation. They can jointly form a  
clean, zero-carbon, electric-centric, flexible, efficient, and interconnected zero-  
carbon energy system that meets different energy demands. Green hydrogen  
comes from green power, and it is equivalent to “third energy”. It can also come  
from power generated by fuel cells or hydrogen fueled gas turbines. Compared  
with other energy sources, hydrogen energy is easier to achieve two-way  
conversion with electricity. A mature and complete green hydrogen production,  
application and allocation system needs to be built based on an economical and  
efficient power system to achieve the complementary advantages of electricity  
and hydrogen and form an electric-centric zero-carbon energy service system.  
5.1 Key Technology Prospects  
The utilization of renewable energy to produce green hydrogen by water electrolysis will  
become the dominant hydrogen production method. By 2030, the high-efficiency and  
high-power alkaline electrolysis technology and low-cost proton exchange membrane  
electrolysis technology are expected to make breakthroughs. The efficiency of electrolytic  
hydrogen production is expected to increase to about 80%, the cost of hydrogen production  
system is expected to decrease to RMB 3000/kW, the LCOEs of photovoltaic power and  
onshore wind power in China are expected to decrease to RMB 0.15/kWh and RMB 0.25/kWh  
respectively, and the cost of green hydrogen is expected to decrease to RMB 15-20/kg.  
Compared with blue hydrogen, it is initially cost-effective, and commercial promotion is started.  
By 2050, new electrolytic hydrogen production technologies such as high-efficiency and  
long-life high-temperature solid oxide electrolysis cell technology and others are expected to  
make breakthroughs. The efficiency of electrolytic hydrogen production is expected to  
increase to about 90%, the cost of hydrogen production system is expected to decrease to  
RMB 2000/kW, the cost of renewable energy power generation is expected to decrease to  
RMB 0.1-0.17/kWh, and the cost of green hydrogen is expected to decrease to RMB 7-11/kg,  
so such technologies will become the dominant hydrogen production methods.  
Gaseous hydrogen storage and liquid hydrogen storage technologies are relatively mature,  
and material-based hydrogen storage needs to be broken through. The technology of gaseous  
hydrogen storage at about 20MPa has matured. For gaseous hydrogen storage at higher  
pressure (70MPa), materials and processes need to be improved to reduce costs. Large-scale  
fixed hydrogen storage is expected to be in the form of high-pressure gaseous hydrogen  
storage with a storage pressure of 15-50MPa, and the current construction cost of hydrogen  
storage equipment is about RMB 1000/kg hydrogen. By 2030, the carbon fiber wound  
high-pressure hydrogen cylinder manufacturing technology is expected to be further mature,  
and the cost of hydrogen storage equipment is expected to decrease to RMB 500-800/kg  
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Conclusion and Prospect  
hydrogen. By 2050 and 2060, it is expected to further decrease to about RMB 300/kg hydrogen  
and RMB 250/kg hydrogen. For small-scale hydrogen storage, full composite light fiber wound  
storage tanks will be used, with the pressure of 35MPa or 70MPa. By 2030, the technology of  
full composite light fiber wound storage tank at 70MPa is expected to be mature, and the cost  
is expected to decrease to RMB 3500/kg hydrogen. By 2050 and 2060, it is expected to further  
decrease to RMB 2000/kg hydrogen and RMB 1500/kg hydrogen. The liquid hydrogen storage  
technology is mature, but the energy consumption is high. For material-based hydrogen  
storage (including metal alloys, ammonia, and organic compounds), different technical routes  
have their own advantages and disadvantages, and generally speaking, the energy  
consumption is high and the purification is difficult.  
Different hydrogen transportation technologies are applicable to different scenarios, and  
appropriate technologies should be selected according to specific situations. In small and  
medium-scale scenarios, gaseous hydrogen tank trucks are mainly used for short-distance  
transportation (<300km), and the unit hydrogen transportation cost is RMB 3-6/kg. The liquid  
hydrogen tank trucks are mainly used for medium-distance transportation (300-100km), and  
the unit hydrogen transportation cost is RMB 5-10/kg. In large-scale scenarios, the combination  
of the replacing hydrogen transportation with power transmission with hydrogen transmission  
through pipelines will be used. At present, the investment cost of hydrogen transportation  
pipelines is about 1.5 times that of natural gas pipelines. By 2030, the pure hydrogen pipeline  
manufacturing technology and the pressure reduction and pressure regulation technology are  
expected to be mature, and the construction cost of large-scale hydrogen transportation  
pipelines is expected to decrease to RMB 13.5 million/km, equivalent to the current cost of  
natural gas pipelines. The transportation loss (including gas loss and energy consumption) per  
1000km of hydrogen transportation pipelines will be controlled at about 1%, and the unit  
hydrogen transportation cost will be controlled at RMB 2.7/kg. By 2050, new hydrogen  
transportation pipelines made of fiber-reinforced polymer composites and others are expected  
to be put into commercial use, the transportation loss per 1000km of hydrogen transportation  
pipelines will be controlled at 0.3%-0.5%, and the unit hydrogen transportation cost will be  
controlled at about RMB 2/kg. By 2060, with the further maturity of hydrogen transportation  
pipeline technology, the transportation loss per 1000km of hydrogen transportation pipelines is  
expected to further decrease to 0.1%-0.2%, reaching the current level of natural gas pipelines,  
and the unit hydrogen transportation cost will be below RMB 2/kg.  
Green hydrogen application technologies in the industry, transportation, and power generation  
fields will mature rapidly and make progress. At present, hydrogen is mostly used in the  
chemical field and is dominated by gray hydrogen. In the future, green hydrogen will become  
an important technical solution for de-carbonization and indirect electricity replacement in  
metallurgy, aviation, and industrial high-quality heat. In the construction field, due to the  
constraints of safety, efficiency and cost, the future application potential is small. By 2030, the  
fuel cell technology is expected to be basically mature, and green hydrogen heavy trucks and  
buses and distributed hydrogen power generation will be gradually promoted and applied. The  
green hydrogen ironmaking technology will be gradually improved and ready for commercial  
promotion. With the decrease of green hydrogen cost, ammonia production from green  
hydrogen will have economic advantages, and methanol and methane production from green  
hydrogen will have demonstration conditions. By around 2035, the pure hydrogen fueled gas  
turbine technology is expected to be mature, and the hydrogen fueled gas turbine power  
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The Development and Outlook of Green Hydrogen  
generation is expected to be put into commercial use. By 2050, the technologies of power to  
fuel or raw materials such as green hydrogen to methanol and methane are expected to be  
mature and have economic advantages.  
5.2 Green Hydrogen Demand Prospects  
Green hydrogen application is an extension of green power application, and it is also an  
important way to achieve indirect electricity replacement in metallurgy, aviation, and industrial  
high-quality heat. In the next ten years, the demand for green hydrogen in China is expected to  
gradually increase. The demand for green hydrogen is expected to reach about 4 Mt by 2030,  
and the demand for green hydrogen in China is expected to rapidly increase to 61 Mt by 2050,  
including 36 Mt of hydrogen used in new industries such as power to raw material and  
metallurgy, 15.5 Mt of hydrogen used for transportation vehicles such as large passenger cars  
and heavy trucks, and 9.5 Mt of hydrogen used in power generation and construction  
industries. By 2060, the demand for green hydrogen in China is expected to reach 75 Mt, and  
the demand for hydrogen in traditional industries such as petrochemical industry and others is  
expected to be 20 Mt and it will still be met by hydrogen in the industrial process. The total  
demand for hydrogen is expected to reach 95 Mt. Based on the economic development model  
and industrial structure of provinces and regions in China, by 2050 and 2060, the demand for  
green hydrogen is expected to be mainly concentrated in central and eastern China,  
accounting for 85% of the country’s total. Considering the cost of carbon emissions, the  
economic advantages of green hydrogen replacing fossil fuels in the industry, power  
generation, and transportation fields will be quickly reflected, and the green hydrogen demand  
will be started 3-5 years in advance.  
Green hydrogen comes from green power, and the development potential far exceeds the  
demand. Therefore, the optimal development scheme should be developed with the overall  
consideration of multiple factors such as resource endowment of renewable energy, water  
sources, and equipment utilization rate. Based on the assessment results of GEIDCO on  
renewable energy resources such as wind energy and solar energy, the technical development  
potential of green hydrogen in China is as high as 3.7 Gt/a. The development potential of green  
hydrogen in China is mainly concentrated in northwest China, accounting for 50% of the  
country’s total. With the decrease in the cost of renewable energy power generation and the  
advancement of electrolytic hydrogen production technology, by 2030, the average green  
hydrogen production cost in China is expected to decrease to about RMB 20/kg and it can be  
as low as RMB 15-16/kg in areas with good wind and solar resources, and green hydrogen is  
initially cost-effective compared with blue hydrogen. The production cost of green hydrogen is  
expected to decrease to RMB 7-11/kg by 2050, and it is expected to further decrease to RMB  
6-10/kg by 2060. Some areas with excellent development conditions in northwest China, such  
as Jiuquan, Gansu and Hami, Xinjiang, will become important green hydrogen production  
bases in China. The cost of hydrogen production can be as low as RMB 5-7/kg. Hydrogen  
production from green power will become the dominant hydrogen production method.  
The green hydrogen allocation infrastructure should be coordinated with the power grid, and  
the optimal allocation pattern of the electricity-hydrogen zero-carbon energy system should be  
considered as a whole. The resources and demands are inversely distributed in space, which  
determines the need for large-scale and long-distance transportation of green hydrogen. In the  
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Conclusion and Prospect  
future, large-scale centralized development will be realized in the areas rich in clean energy in  
the western region. On the basis of meeting the local demand for electricity and hydrogen, the  
surplus clean energy will be mainly transmitted to the energy-consumption centers in eastern  
and central regions via the “West-to-East Power Transmission” channel, and green hydrogen  
will be produced for outbound transportation by using the hydrogen transportation (gas  
transmission) pipeline network. By 2030, the total amount of inter-regional hydrogen  
transportation between the western region and the eastern and central regions is expected to  
be 1 Mt, and the mode of replacing hydrogen transportation with power transmission will be  
used. By 2060, the inter-regional hydrogen transportation scale in China is expected to reach  
45% of the total demand for green hydrogen. Nearly 25% of hydrogen is transmitted directly by  
pipelines, and the transportation of more than 75% of hydrogen is achieved through UHV Grids  
by using the mode of replacing hydrogen transportation with power transmission. The  
electricity-hydrogen zero-carbon energy system can give full play to the advantages of easy  
transmission of power and easy storage of hydrogen. The coordinated allocation of electricity  
and hydrogen will improve the flexibility and utilization efficiency of the system to reduce the  
overall energy consumption cost.  
5.3 Green Hydrogen Industry Prospects  
With the increasing demand for deep de-carbonization and the improvement of green  
hydrogen cost-effectiveness, green hydrogen will gradually penetrate into the industry,  
transportation, construction, and power generation fields. By 2060, the demand for green  
hydrogen is expected to reach 75 Mt, the installed capacity of electrolytic hydrogen production  
equipment is expected to reach more than 800 GW, the number of hydrogen fuel cell vehicles  
is expected to reach 40 million, and the installed capacity of hydrogen power generation  
equipment is expected to reach 200 GW. In the next 40 years, the green hydrogen industry will  
gradually undergo a development process from scratch and from small to large, and  
corresponding supporting mechanisms are required in hydrogen energy policy planning,  
green hydrogen industry chain construction, and market platform.  
5.3.1 Policy Planning  
The top-level design of China’s hydrogen energy industry has gradually become clear, and  
policy planning needs to lay a solid foundation for long-term steady development. Among the  
development priorities identified in the National Outlines for Medium and Long-term Planning  
for Scientific and Technological Development (2006—2020) issued by the State Council in  
2006, “hydrogen energy and fuel cell technology” is listed as an advanced energy technology  
developed at the national priority. According to the Notice on Launching Fuel Cell Vehicle  
Demonstration Projects issued in September 2020, the policy of “replacing subsidies with  
rewards” has been implemented since September 2020 for the national subsidies for hydrogen  
energy. With the demonstration application of new technologies and tackling key problems of  
key core technologies as the guidance, cities with good basic conditions of hydrogen energy  
are recommended to declare to be demonstration city groups, aiming to form a new industrial  
development model with reasonable layout, different focuses, and coordinated promotion,  
which ensures that the subsidy is targeted, and is conducive to truly supporting enterprises  
with advanced technology and strong market competitiveness. The Working Guidance for  
Carbon Dioxide Peaking and Carbon Neutrality in Full and Faithful Implementation of the New  
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The Development and Outlook of Green Hydrogen  
Development Philosophy issued by the CPC Central Committee and the State Council in  
September 2021 clearly proposes to develop hydrogen energy, promote the development of  
the whole chain of “production, storage, transportation and consumption” of hydrogen energy  
as a whole, promote the construction of hydrogen refueling stations, advance the tackling key  
problems of hydrogen production technology from renewable energy, and strengthen the  
research, development, demonstration and large-scale application of key technologies of  
hydrogen energy production, storage and application.  
In addition to the strategic emphasis at the national level, 31 provinces, municipalities and  
autonomous regions across the country have issued relevant policies for the development of  
hydrogen energy industry. Some places such as Anhui, Hunan, Yunnan, Heilongjiang, and  
Shaanxi have deployed and planned hydrogen energy development in comprehensive policy  
planning documents such as the Fourteenth Five-Year Plan and the Outline of Long-Range  
Objectives in 2035 for National Economic and Social Development and others. In addition to  
comprehensive planning documents, some places such as Beijing, Shandong, Hebei, Tianjin,  
Sichuan, Zhejiang, and Ningxia have issued special policies or plans related to hydrogen  
energy. Some provinces and cities have issued the hydrogen energy industry construction  
goals through relevant policies and plans for hydrogen fuel vehicles.  
The policy framework for the development of hydrogen energy industry has been gradually  
improved. It is mainly manifested in three aspects: First, there are many government  
departments and agencies that issue policy documents, including the Ministry of Finance, the  
Ministry of Industry and Information Technology, the Ministry of Science and Technology, the  
National Development and Reform Commission, the Ministry of Justice, the National Energy  
Administration, the Customs Tariff Commission, and the Standardization Administration of the  
People’s Republic of China. Many policy documents are jointly formulated and issued by more  
than two ministries, commissions and bureaus, which indicate that the development of  
hydrogen energy industry has been promoted to a national strategy and has attracted high  
attention from relevant ministries, commissions and bureaus. Second, the policy documents  
cover all aspects affecting the hydrogen energy industry, including planning and layout for the  
development of hydrogen energy industry, all links in the industry chain such as hydrogen  
production, hydrogen storage, fuel cell, and hydrogen refueling station, as well as support key  
points of hydrogen energy technology R&D, application process and evaluation methods of  
hydrogen energy support projects, which greatly improves the systematicness and  
preciseness of hydrogen energy support policies. Third, the policy means mainly include  
government planning guidance and financial subsidies. Meanwhile, the development of the  
domestic hydrogen energy equipment manufacturing industry can be supported by promoting  
the formulation of technical standards for industrial development to guide healthy competition  
in the industry and reducing the tariffs on some key imported parts and components in the  
hydrogen energy industry chain to reduce import costs. So far, China has issued and  
implemented 80 national standards and about 40 industry standards on hydrogen energy and  
fuel cell technology, application, testing, and safety. These technical specifications and  
standards have played a positive role in promoting the standardized development of hydrogen  
energy and hydrogen fuel cell vehicles.  
With the increasingly mature of green hydrogen technology and the reduced cost, supporting  
policies for hydrogen energy should be adapted to the change in market demand, and the  
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Conclusion and Prospect  
priority should be clarified. From the middle of the 14th Five-Year Plan to 2030, the low-carbon  
clean hydrogen production projects will be in the ascendant, the market penetration will be  
accelerated, and the cost-effectiveness will be solved. The policy needs should focus on  
sorting out the restrictive clauses for the development of green hydrogen in various fields, to  
fully encourage various market entities to expand the technology R&D and project scale,  
actively explore supplementary policies such as “carbon tax” and others, and formulate  
standards and specifications. After 2030, green hydrogen application, production, storage,  
and transportation technologies will be gradually mature to achieve parity, the market scale will  
grow rapidly, and the competitiveness in the final application fields will be continuously  
enhanced. Direct policy support is not required for the long-term development of green  
hydrogen. The impact of green hydrogen on carbon neutrality and related industries should be  
comprehensively evaluated to ensure efficient flow of funds and enhance the value cognition of  
green products.  
The industrial coordination strategy should be vigorously developed to speed up the transfer to  
green industries. Green hydrogen production can effectively consume renewable power such  
as wind power and photovoltaic power to realize the storage of surplus energy in valley periods  
and promote the green and healthy development of methanol and ammonia synthesis  
industries. In the context of the energy transition, green hydrogen will become a major  
component of the hydrogen energy market. With the grid parity of renewable energy power  
generation and the continuous decline of green hydrogen cost, the policies will focus on the  
coordinated development of downstream industries, and high energy-consuming enterprises  
or production links such as metallurgic and chemical will be transferred to areas with rich  
renewable energy resources such as northwest China, northeast China, north China, and  
southwest China. In the local areas, large-scale “zero-carbon plants” will be built by utilizing  
wasteland resources such as deserts, wildernesses, and Gobi Deserts. Through the integration  
of power, grid, load, and storage and multi-energy complement cooperation with green  
hydrogen production, the clean energy supply of energy-consuming enterprises will be  
effectively solved, and the problem of large-scale consumption and storage of renewable  
energy will also be solved. The green hydrogen metallurgy industry and green hydrogen  
chemical industry will be vigorously developed to help iron and steel and chemical industries  
for which the carbon reduction is difficult to achieve the clean transition. The targeted support  
should be provided for scientific research and demonstration projects, and production  
enterprises and technical departments should continue to invest in green hydrogen application  
innovation. The flexible and diverse policy means should be used to spread risks for hydrogen  
energy application projects to increase the enthusiasm of enterprises to build demonstration  
projects.  
The building of an electricity-hydrogen coordinated energy system should be actively  
encouraged to solve the problem of green hydrogen transportation. Large-scale transportation  
of hydrogen is one of the biggest bottlenecks in developing the green hydrogen industry. The  
replacing hydrogen transportation with power transmission is out of the constraint of direct  
hydrogen transportation itself. It proposes the best solution for the long-distance and  
large-scale allocation of green hydrogen. The development of hydrogen infrastructure in the  
future should be coordinated with the planning and construction of the power grid. By building  
the electricity-hydrogen coordinated energy transmission and allocation system and exploring  
the flexibility value of green power-green hydrogen connection, the consumption of renewable  
187  
The Development and Outlook of Green Hydrogen  
energy can be promoted to provide a security guarantee for power safety and stability. Priority  
should be given to the construction and reconstruction of infrastructures such as  
hydrogen-enriched compressed natural gas pipelines and large-capacity hydrogen  
transportation pipelines, and large-scale electricity and hydrogen transportation channels  
should be planned and designed as a whole, to form a pattern of combining allocation of green  
hydrogen for local production and utilization with large-scale optimization across the country at  
an early date.  
The hydrogen energy management system and technical standard system should be  
improved quickly to strive to remove various policy barriers. In 2020, the National Bureau of  
Statistics included hydrogen in the energy statistics report for the first time. The fuel gas  
management regulations are mostly used as the management standards in the management  
regulations on local hydrogen refueling stations. Relevant departments should accelerate  
research and establish an effective coordination and linkage mechanism as soon as possible,  
scientifically analyze the safety of hydrogen for fuel cells, determine a safe and reasonable  
hydrogen management mode, and include hydrogen energy in the national energy strategy  
system. They should face the danger of hydrogen squarely, establish and improve the  
hydrogen production safety responsibility system and standardized management system, and  
manage hydrogen as energy rather than hazardous chemicals. The new development plans  
should be made to remove standard detection barriers and market access barriers that restrict  
the development of hydrogen energy as soon as possible from the policy level.  
5.3.2 Industry Chain Development  
In the future, China’s green hydrogen industry chain will develop into a green hydrogen-based  
industry chain, involving upstream renewable energy electrolytic hydrogen production  
enterprises, midstream hydrogen storage and transportation enterprises, hydrogen refueling  
station construction operators, and various downstream hydrogen application fields. At present,  
China’s hydrogen is mainly used in petrochemical industries such as petroleum refining,  
ammonia synthesis, and methanol synthesis, and a small amount of hydrogen is used as  
industrial fuel. In the future, China will achieve a wider range of green hydrogen utilization,  
covering many fields such as transportation, chemical, power generation, metallurgy, and  
heating.  
In terms of upstream hydrogen production, it is critical to promote the large-scale production of  
upstream green hydrogen and reduce the electricity price of renewable energy and the cost of  
electrolysis cells. With the increasing demand for deep de-carbonization and the improvement  
of green hydrogen cost-effectiveness, the hydrogen energy supply structure will gradually  
transition from gray hydrogen dominated by fossil fuels to green hydrogen dominated by  
renewable energy, which will help build a new power system dominated by renewable energy.  
China’s renewable energy industries such as photovoltaic power and wind power are  
developing rapidly. With the technological progress and scale effect, the renewable energy  
resources in northwest China, northeast China, and southwest China will be fully developed,  
and the LCOE of photovoltaic power and wind power will continue to decrease. With the  
macro-policy control and the continuous progress of technology, electrolysis cells will have  
larger cells, better manufacturing process, and quality control, key technologies such as  
alkaline electrolysis cell, proton exchange membrane electrolysis cell and solid oxide  
188  
5
Conclusion and Prospect  
electrolysis cell will be upgraded and optimized, bottlenecks will be broken through, and the  
cost of electrolysis cell system will be reduced. The total installed capacity is expected to  
reach 800 GW by 2060. In the future, the production cost of green hydrogen will continue to  
decrease and the production scale will continue to increase. The proportion of green hydrogen  
on the hydrogen supply side will gradually expand, and the proportion on the supply side will  
continue to increase from less than 1% at present to more than 80% by 2050. The average  
selling price of green hydrogen is calculated at a gross margin of 10%. The market space on  
green hydrogen supply end in China is expected to reach RMB 80 billion, RMB 700 billion, and  
RMB 800 billion by 2030, 2050, and 2060.  
In terms of midstream hydrogen storage and transportation, improving the energy utilization  
rate and balancing the production and consumption efficiently are the keys to the green  
development of the whole industry chain. Large-scale regional hydrogen dispatching will  
become an important link in the building of a low-carbon clean hydrogen supply system.  
Through the flexible combination of pure hydrogen pipeline, hydrogen-enriched compressed  
natural gas pipeline, replacing hydrogen transportation with power transmission, gaseous  
hydrogen trailer, liquid hydrogen tanker truck, and hydrogen transportation with hydrogen  
carriers such as liquid ammonia and others, an electricity-hydrogen coordinated transmission  
allocation system will be built to effectively reduce the transportation cost and carbon  
emissions and play the role of hydrogen itself as an energy interconnection medium. The  
construction of infrastructures such as hydrogen refueling stations and others is a key part of  
future infrastructure construction. As the scale of hydrogen transportation expands, the market  
demand for hydrogen refueling stations is gradually increasing. At present, the cost of  
hydrogen refueling stations is high, and it will develop rapidly in areas with good economic  
foundations and large-scale hydrogen fuel cell vehicle promotion conditions in the near future.  
At the end of 2020, the number of hydrogen refueling stations in China was 128. The number of  
energy supply stations with hydrogen refueling functions is expected to reach more than  
10,000 by 2050A, which can meet the demand for hydrogen supply in transportation and other  
fields. At present, core equipment such as compressors and refueling machines in hydrogen  
refueling stations are still imported. With the continuous development of China’s hydrogen  
energy industry and the urgent need to improve the localization process of core equipment, the  
market scale of future hydrogen refueling infrastructure in China is expected to exceed RMB  
100 billion from 2030 to 2050.  
In terms of downstream hydrogen application, the innovation of key technologies in the  
application field should be encouraged to break through the “bottleneck” link. In the short term,  
green hydrogen will first be demonstrated on a large scale in the transportation field, and  
hydrogen fuel cell vehicles will achieve clean replacement in the bus and heavy truck fields. At  
present, core materials such as proton membranes and catalysts are highly dependent on  
foreign countries. There are very few key hydrogen energy equipment manufacturing  
enterprises in China, and there is a bottleneck in technology. We will encourage technological  
innovation in application fields and realize the localization of hydrogen energy equipment and  
core equipment to promote the sound development of green hydrogen industry chain in China.  
In the long term, as the cost of green hydrogen continues to decrease, green hydrogen will  
penetrate into power generation, chemical, iron and steel smelting, and high-grade heating  
ASource: China Hydrogen Alliance, White Paper on China’s Hydrogen Energy and Fuel Cell Industry (2020).  
189  
The Development and Outlook of Green Hydrogen  
fields, and form an industrial scale in the aviation and marine fuel synthesis, green chemical,  
and hydrogen metallurgy fields.  
5.3.3 Market and Service Platform  
We will vigorously promote the basic capacity building of the green hydrogen market, establish  
the standard, measurement, testing and certification system, gradually build a unified, open,  
competitive and orderly green hydrogen market system, and strive to remove various policy  
barriers to improve the sustainability of green development.  
Building a green hydrogen trading platform to form a pattern of joint participation of diversified  
market entities. We will promote the interaction between supply and demand and support the  
equal access of various market entities according to law to form a pattern of joint participation  
of diversified market entities, and will support the use of existing sites and facilities to carry out  
the comprehensive supply of oil, gas, hydrogen, and electricity. We will build a green hydrogen  
market combining hydrogen transactions such as medium and long-term transactions and spot  
transactions with auxiliary service transactions, so that zero-emission technologies can be  
compensated and rewarded in the market, and the endogenous power of technology  
application enterprises can be enhanced.  
Establishing an industry fund to promote the efficient circulation of social capital in the green  
hydrogen industry chain. At present, the amount of investment and financing in the hydrogen  
energy industry is increasing rapidly, and central enterprises, state-owned enterprises, and  
private listed companies have become the important pillars in the hydrogen energy industry.  
The hydrogen energy industry chain involves various industries, with wide and complex  
technologies. In addition to large pillar enterprises, we also need to encourage and support the  
development of a number of “specialized and advanced” small and medium-sized enterprises  
that focus on tackling key technologies and bottlenecks, so as to serve the overall improvement  
of the hydrogen energy industry chain. Therefore, we need to continuously improve the  
investment and financing links of the hydrogen energy industry, and support enterprise  
development and encourage technological innovation by establishing industry funds.  
Promoting the improvement of carbon market in China to give full play to the role of carbon  
pricing in promoting the development of hydrogen energy. With the opening of carbon  
emission rights trading, green transition actions in various industries will be gradually  
implemented in various quantitative goals. During the 14th Five-Year Plan period, it will be  
gradually included in many high-efficiency industries such as petrochemical, chemical,  
building material, steel, nonferrous metal, paper making, and aviation. Additional benefits will  
be gained from carbon reduction projects, and new development opportunities will be brought  
to the hydrogen application. In the context of the global energy transition, green international  
trade barriers such as “carbon border tax” and “border adjustment fee” have gradually formed,  
so countermeasures need to be deployed in advance. We will promote carbon pricing and  
improve carbon tax policies to effectively promote the development of the green hydrogen  
industry and reduce the carbon footprint in all links of products, enhancing China’s voice in  
international trade.  
Building diversified and multi-level comprehensive services, and building a multi-level and  
190  
5
Conclusion and Prospect  
diversified innovation platform. We will focus on the key and common technical links in the  
industry chain and build a multi-level and diversified innovation platform. We will encourage  
industry organizations and leading enterprises to take the lead in building product inspection  
and testing platforms. We will also strengthen the integration of hydrogen energy infrastructure  
construction and digital economy, build a big data platform for the hydrogen energy industry,  
and establish a data statistics system and development research system for the domestic  
hydrogen energy industry, to promote scientific decision-making.  
191  
Appendix  
Appendix  
Appendix 1 Basic Data Sources and Details  
Hydrology, wind speed, solar radiation and other resource data are the basis for the  
assessment on hydroenergy, wind energy and solar energy resources. To realize digital and  
multi-dimensional assessment on hydroenergy, wind energy and solar energy resources,  
geographic information data such as global land cover distribution, as well as data related to  
human activities such as global transportation and grid infrastructure distribution are  
introduced in the report, so that multi-dimensional assessment and calculation of technical  
potential installed capacity and economic potential installed capacity can be made based on  
the assessment of theoretical potential. On the whole, a basic database of global renewable  
energy resource assessment is established in the study, including 18 items of data in three  
categories covering the whole world, as shown in Attached Table 1.  
Attached Table 1 Data Sources and Details of GREAN Platform  
Category  
Data description  
Data source, spatial resolution, data type  
Data Source: global wind energy meteorological resource  
data, calculated and produced by Vortex1. Spatial Resolution:  
9km×9km. Data Type: raster data  
Global mesoscale wind  
resources data  
Data of  
resources  
Data Source: global solar energy meteorological resources  
data , calculated and produced by GeoModel Solar2 Spatial  
Resolution: 9km×9km. Data Type: raster data  
Global solar energy  
resource data  
The classification information of land covers in the world is  
from the identification data of 10 major land cover types, such  
Classification information of as forest, grassland, and cultivated land, covering the land  
global land covers  
range from 80 degrees north latitude to 80 degrees south  
latitude released by the National Geomatics Center of China.  
Spatial Resolution: 30m×30m. Data Type: raster data  
Data on the distribution of major reservoirs in the world is  
Global distribution of major from the global water system projects in Bonn, Germany,  
reservoirs  
including more than 6500 artificial reservoirs with a cumulative  
Geographic  
information  
data  
storage capacity of about 6.2 trillion m3 (Raster Data)  
Data on the distribution of lakes and wetlands in the world  
are jointly developed by the World Wide Fund for Nature  
Global distribution of lakes (WWF), the Research Center for Eco-Environmental Sciences,  
and wetlands  
and the University of Kassel (Germany), including lakes and  
permanent open water bodies other than artificial reservoirs.  
Spatial Resolution: 1km×1km. Data Type: raster data  
The distribution data of major geological faults in the world  
are from the American Environment Systems Research  
Institute (Vector Data)  
Global distribution of major  
geological faults  
193  
The Development and Outlook of Green Hydrogen  
continued  
Category  
Data description  
Data source, spatial resolution, data type  
The distribution data of global plate boundary in the world  
are from the American Environmental Systems Research  
Institute (Vector Data)  
Global distribution of plate  
boundaries  
Data on the distribution of historical seismic activity  
frequency come from the World Resources Institute (WRI),  
including the geographical distribution of earthquakes with  
magnitude 4.5 or higher since 1976. Spatial Resolution: 5  
km×5 km. Data Type: raster data  
Global distribution of historical  
seismic activity frequency  
Data on the distribution of major stratum in the world is from  
the joint research results of the European Commission,  
German Federal Ministry of Education and Research, German  
Science Foundation and other institutions (Vector Data)  
Global distribution of main  
rock types  
Geographic  
information  
data  
Data on global terrain elevation is from the digital products  
of the National Aeronautics and Space Administration and  
Ministry of Economy Trade and Industry. Spatial Resolution:  
30m×30m. Data Type: raster data  
Global terrain elevation data  
Data on the global ocean boundary is from the Flanders  
Marine Institute (VLIZ) in Belgium, including the  
200-nautical-mile exclusive economic zone, 24-nautical-mile  
contiguous zone, 12-nautical-mile territorial sea area and  
other information stipulated in the United Nations Convention  
on the Law of the Sea (Vector Data)  
Global ocean boundaries  
data  
Data on the distribution of major conservation areas in the  
world is from the global data set of conservation areas jointly  
released by the International Union for Conservation of Nature  
Global distribution of major (IUCN) and the World Conservation Monitoring Center of the  
conservation areas  
United Nations Environment Programme (UNEP-WCMC). Such  
data in the report has been translated, classified and sorted  
out according to the classification standards of conservation  
areas in China (Vector Data)  
Data on the global population distribution is from the Center  
for International Earth Science Information Network of  
Global population distribution Columbia University, including the population distribution data  
in 2000, 2005, 2010, and 2015. Spatial Resolution:  
900m×900m. Data Type: raster data  
Human  
activities and  
economic  
data  
Data on the distribution of global transportation infrastructure  
is from the global railway, airport and port data set released by  
Global distribution of  
the North American Cartographic Information Society (NACIS)  
transportation infrastructure and the global road network data set released by the  
Socioeconomic Data and Applications Center of NASA (Vector  
Data)  
Data of the global grid geographic wiring diagram is from the  
Global Energy Interconnection Development and Cooperation  
Organization, covering the backbone transmission network  
data of 147 countries in Europe, Asia, America, Africa and  
Oceania as of the end of 2017, including 110kV-1000kV AC  
power grids and major DC transmission projects (Vector Data)  
Geographic distribution of  
global power grid  
194  
Appendix  
continued  
Category  
Data description  
Data source, spatial resolution, data type  
The global power plant information and geographical  
distribution data are from the joint research results of Google,  
Royal Institute of Technology in Stockholm and World  
Resources Institute (WRI), including the location distribution  
and installed capacity of global power plants such as  
thermal power, hydropower, nuclear power, wind power, PV  
power and biomass power generation as of the end of 2017  
(Vector Data)  
Human  
activities and  
economic  
data  
Global power plant  
information and geographical  
distribution  
Note 1. Vortex System Technical Description, January 2017.  
2. Solargis Solar Resource Database Description and Accuracy, 2016 October.  
195  
The Development and Outlook of Green Hydrogen  
Appendix 2 Recommended Values of Main Parameters for Wind, Light, and Clean  
Energy Assessment  
The assessment model of wind and light clean energy includes three levels: theoretical  
potential, technical exploitation capacity, and economic potential installed capacity. Among  
them, the technical exploitation capacity refers to the total installed capacity that can be  
developed at the technical level in the assessment year. The key to the assessment is to  
exclude areas that are not suitable for development due to the limitations of resource  
endowment, conservation area, altitude and sea depth, land covers in combination with  
different development methods. See Attached Table 2 for main indicators and recommended  
parameters. Economic potential installed capacity refers to the total installed capacity with a  
competitive advantage compared with local average on-grid electricity price or other  
alternative electricity prices in the technical exploitable quantity in the year of evaluation.  
Besides being related to resource conditions, technical and economic level of power  
generation equipment and policy environment, it is also closely related to the power delivery  
cost that affects the power generation cost. With reference to the technical standards of the  
power grid and the cost of power transmission and transformation projects in China, the report  
provides the recommended values for cost-effectiveness parameters of renewable energy  
development and grid integration, such as the selection conditions of onshore and offshore  
power transmission modes, and the unit transmission cost of different types of long-distance  
power transmission projects. See Attached Table 3 and Attached Table 4 below for details.  
Attached Table 2 Main Indicators and Recommended Parameters Used in the  
Assessment Model of Technical Potential Installed Capacity  
Development parameters  
of wind energy  
Development  
parameters of PV  
Type  
Restriction  
Threshold value  
—
Centralized Centralized Distributed Distributed  
Resource  
restrictions  
Wind speed Wind Speed  
GHI>1000kWh/m2  
Wind Speed and GHI  
>5m/s  
>4.5m/s  
Land  
elevation  
< 4000m  
Technical  
development  
restrictions  
Altitude and Sea  
Depth  
Altitude of Land  
< 4500m  
—
Depth of  
coastal waters  
< 150m  
0%  
Not suitable for  
development  
Natural ecosystem  
Wildlife  
0%  
0%  
0%  
0%  
0%  
0%  
0%  
0%  
0%  
0%  
0%  
0%  
0%  
0%  
0%  
Not suitable for  
development  
0%  
0%  
0%  
0%  
Conservation  
area  
restrictions  
Not suitable for  
development  
Natural relics  
Natural resources  
Not suitable for  
development  
Other  
conservation areas  
Not suitable for  
development  
196  
Appendix  
continued  
Development parameters  
of wind energy  
Development  
parameters of PV  
Type  
Restriction  
Threshold value  
Centralized Centralized Distributed Distributed  
Not suitable for  
centralized  
development  
Forest  
0%  
0%  
10%  
25%  
0%  
0%  
0%  
Not suitable for  
centralized  
Cultivated land  
10%  
development  
Not suitable for  
development  
Wetland and swamp  
Urban  
0%  
0%  
0%  
80%  
80%  
100%  
1
0%  
0%  
0%  
0%  
0%  
0%  
1
0%  
0%  
0%  
50%  
80%  
100%  
1
0%  
25%  
0%  
0%  
0%  
0%  
1
Not suitable for  
development  
Land cover  
restrictions  
Not suitable for  
development  
Ice and Snow  
Shrub  
Suitable for  
development  
Herbaceous  
vegetation  
Suitable for  
development  
Suitable for  
development  
Bare ground  
0-1.7°  
Suitable for  
development  
Suitable for  
development  
1.8°-3.4°  
3.5°-16.7°  
16.8°-30°  
>30°  
0.5  
0.5  
0.3  
0.15  
0
1
1
Terrain slope  
restrictions  
Suitable for  
development  
0.3  
1
1
Suitable for  
development  
0.15  
0
1
1
Not suitable for  
development  
0
0
Attached Table 3 Selection of Power Transmission Modes  
Location of base  
Distance from main grid (km)  
Power transmission mode  
AC  
＜500  
≥500  
＜150  
≥150  
Onshore  
Offshore  
±800kV DC  
220kV AC  
±320kV flexible DC  
197  
The Development and Outlook of Green Hydrogen  
Attached Table 4 Recommended Values of Grid Connection Economic Parameters  
Onshore AC transmission  
Voltage class (kV)  
1000  
Transmission distance (km)  
Unit transmission cost [USD/(km·kW)]  
500  
0.28  
0.34  
0.39  
0.59  
0.65  
1.06  
1.37  
745-765（750）  
500  
400  
300  
380-400（400）  
300-330  
220  
200  
220  
150  
110-161（110）  
100  
Onshore DC transmission  
Transmission distance (km)  
3000-5000  
Voltage class (kV)  
±1100  
Unit transmission cost [USD/(km·kW)]  
0.14  
0.15  
0.30  
±800  
1500-3000  
±500  
800-1200  
Offshore AC transmission  
Transmission distance (km)  
150  
Voltage class (kV)  
220  
Unit transmission cost [USD/(km·kW)]  
3.33  
Offshore DC transmission  
Transmission distance (km)  
150-400  
Voltage class (kV)  
±320  
Unit transmission cost [USD/(km·kW)]  
1.26  
Note: obtained through calculation based on the cost and transmission capacity of typical AC and  
DC transmission projects in China.  
198  
Appendix  
Appendix 3 Resource-Assessment-Demand Hierarchical Optimization Algorithm  
When carrying out the LP optimization of green hydrogen potential and cost, due to the limited  
calculation capability and time-consuming, it is difficult to complete the coordinated  
optimization of tens of millions of geogrid points at the same time. Therefore, how to carry out  
the optimization calculation scientifically, reasonably, and hierarchically is of vital importance.  
Specifically, the research adopted 9km×9km spatial resolution data of wind and solar  
resources. To carry out the technical and economic assessment more accurately, the  
500m×500m spatial resolution was adopted to calculate the technical exploitation amount and  
LCOE. Therefore, based on the GEI scenario projection, because the research often takes the  
vast space of countries or continents as the unit to carry out the analysis of hydrogen demand,  
the region to be optimized will contain tens of thousands or even hundreds of thousands of  
resource data and tens of millions of assessment results, and the optimization calculation  
research is characterized by massive data, time-consuming and low efficiency.  
Therefore, the “Resource - Assessment - Requirement Hierarchical Optimization Algorithm” is  
proposed. On the one hand, the resolution fusion of resources and assessment results is  
realized, and the weighted average method is adopted to unify the resolution of assessment  
data to 9km×9km, which reduces the number of variables and improves the optimization  
efficiency. On the other hand, since the preparation potential of green hydrogen is positively  
related to the technically developable capacity of resources, and negatively related to the  
LCOE, the hierarchical optimization ratio is proposed, and the mathematical expression is as  
follows:  
Cap  
LCOE  
ξ =  
Cap AverLCOE  
The space to be optimized is partitioned according to the appropriate resolution. For each  
sub-region, calculate the ratio of its technical exploitation capability Cap to the total space to  
be optimized, and the ratio of the LCOE to the AverLCOE calculated according to the  
weighted average of annual power generation. The product of the two is the hierarchical  
optimization ratioξ . At last, the total demand for green hydrogen in all spaces to be optimized  
is weighted according to the hierarchical optimization ratio to obtain the total green hydrogen  
preparation in sub-regions, which is used as the boundary condition to develop the potential  
and optimize the cost of green hydrogen.  
199  
The Development and Outlook of Green Hydrogen  
Appendix 4 Optimization Model and Method of Electro-hydrogen Coordinated System  
1. Objective Function of Model  
The model is a kind of linear optimization model, and the optimization objective is to minimize  
the total annual cost:  
minCtot = Cinv + Cfix + Cvar + Cfuel  
Formula 1  
Where: Ctot is total annual cost; Cinv is annual investment cost; Cfix is annual fixed operating  
cost;Cvar is annual variable operating cost;Cfuel is Fuel costs.  
2. Calculation of Various Cost Items  
(1) Investment costs  
Cinv  
=
CRF UC  
kp  
Formula 2  
Formula 3  
inv, p  
p
′
′
CRF = (1 + i) i / (1 + i) −1  
Where:UCinv, p is the annual investment cost per unit capacity of process p of a certain type of  
device in the system, which can be a power plant, a hydrogen production device, a methane  
device, etc.; kp is the capacity of process p of a certain type of device in the system; CRF,  
capital recovery factor, calculated as follows;i is interest rate; l is life of plant.  
(2) Fixed operation cost  
Cfix  
=
UC  
kp  
Formula 4  
fix, p  
p
Where:UCfix, p is Fixed operating cost per unit capacity of process p of a certain type of device  
in the system.  
(3) Variable operation cost  
Cvar  
=
UC  
ap,t  
Formula 5  
  
var, p  
p
t
Where:UCvar, p is Variable operating cost per unit of process p of a certain type of device  
in the system; ap,t is the output of process p of a certain type of device in the system in  
the t hour.  
200  
Appendix  
3. Model Constraints  
(1) Capacity Constraints  
For any factory, the output shall not exceed the capacity at any time:  
a
p,t ≤kp,t ∀p∈ P,t ∈T  
Formula 6  
(2) Material/Energy Balance  
For any merchandise m, any time, any technology, and in, out, and storage of the commodity  
shall keep the material balance  
mbm,t  
=
flin  
−
flout  
∀m∈ M ,t ∈T  
Formula 7  
m, p,t  
m, p,t  
p
p
in  
m, p,t  
out  
m, p,t  
where: fl  
and fl  
the inflow and outflow of the merchandise m. If m is available for sale,  
the quantity for sale at moment t is:  
d
m,t ≤mbm,t ∀m∈ M,t ∈T  
Formula 8  
where: dm,t is the quantity for sale or demand of commodity m at moment t.  
(3) Material/Energy Conversion  
in  
p,m,t  
in  
p,m  
fl  
fl  
= R τ p,t ∀p∈ P,m∈M,t ∈T  
Formula 9  
out  
p,m,t  
out  
= R τ p,t ∀p∈ P,m∈M,t ∈T  
Formula 10  
p,m  
in  
out  
where:τ p,t is the operating condition of plant p at moment t. R and R are the conversion  
p,m  
p,m  
ratios of the merchandise m in the plant p. Assuming that plant p feeds m1 and products m2,  
the conversion efficiency is:  
out  
p,m2  
in  
p,m1  
η = R  
/ R  
Formula 11  
(4) Technical Capacity Flux  
Δt Ppmin kp ≤τ p,t ≤Δt kp  
Formula 12  
τ p,t −τ p,t−1 ≤Δt PRpmax kp ∀p∈ P,t ∈T  
where: Ppmin is the lowest unit operating condition of plant p; PRpmax is the maximum unit  
ramp-up and ramp-down ramp rate of plant p.  
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The Development and Outlook of Green Hydrogen  
(5) Intermittent Supply  
in  
m, p,t  
fl  
= Δt TSm, p,t kp ∀p∈ P,m∈ M,t ∈T  
Formula 13  
where:TSm, p,t is a time sequence of plant p capacity, with a characteristic of intermittence.  
(6) Transmission Constraints Between Nodes  
knn ,tl,m = kn n,tl,m ∀n∈ N,tl ∈TL,m∈ M  
Formula 14  
′
′
where:n is a node; n’ is another node; nn’ represents the transmission direction from node n to  
node n’. Assuming that the transmission is a two-way transmission and the transmission  
capacity of both directions is equal, and tl is the transmission line  
The actual transmission quantity ann ,tl,m,t at any moment t shall not be greater than its  
′
transmission capacity  
a
nn ,tl,m,t ≤knn ,tl,m ∀n∈ N,tl ∈TL,m∈ M,t ∈T  
Formula 15  
′
′
Transmission loss, and ηnn tl,m is the transmission efficiency of merchandise m in the  
′
transmission line tl  
in  
fl  
=ηnn tl,m fllo′ut  
∀n∈ N,tl ∈TL,m∈M ,t ∈T  
Formula 16  
′
′
nn ,tl,m,t  
n ,tl,m,t  
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