Green Hydrogen: True Green Energy

Hydrogen primarily exists in the form of compounds in water and fossil fuels. As a secondary energy source, hydrogen energy must be extracted through hydrogen production technologies.

Based on the source of hydrogen production and the emissions generated during the production process, hydrogen is further categorized as gray hydrogen, blue hydrogen, and green hydrogen.

I. What are gray hydrogen, blue hydrogen, and green hydrogen?

Gray hydrogen

Gray hydrogen is hydrogen produced as a byproduct of the combustion of fossil fuels (such as oil, natural gas, and coal) and industrial processes, with the production process accompanied by substantial carbon dioxide emissions. Currently, gray hydrogen accounts for approximately 95% or even more of global hydrogen production.

Blue hydrogen

Blue hydrogen is produced from gray hydrogen via steam methane reforming or autothermal steam reforming of natural gas, and it employs advanced technologies such as carbon capture, utilization, and storage (CCUS) to reduce carbon emissions by 90%, thereby achieving low-carbon hydrogen production. However, the conditions required for CO₂ sequestration are extremely stringent, which significantly hinders the development of blue hydrogen.

Green hydrogen

Green hydrogen is produced by first generating electricity from renewable energy sources—such as solar, wind, and nuclear power—and then using this electricity to produce hydrogen via water electrolysis. Since the production process generates only water and virtually zero carbon emissions, green hydrogen is hailed as the purest form of green new energy and plays a crucial role in the global transition to renewable energy.

Industry Status Map of Gray, Blue, and Green Hydrogen

Current Status Map of Domestic Production of Gray, Blue, and Green Hydrogen

II. Prospects for the Development of Green Hydrogen

Currently, with the rapid development of new energy sources such as wind power and photovoltaics, renewable-energy-powered water electrolysis for hydrogen production has become a focal point of attention—producing “green hydrogen” from “green electricity.” According to the requirements of the 14th Five-Year Plan and the dual-carbon goals, China’s energy structure will undergo significant adjustments, and the hydrogen supply system will also undergo substantial changes. One important direction in this transformation is the substitution of green hydrogen.

According to incomplete statistics from Yaha Consulting, in the first half of 2022, green hydrogen projects in China experienced an explosive growth. Major domestic energy companies and listed corporations have been actively deploying green hydrogen projects, including PetroChina, State Power Investment Corporation, China Huadian Corporation, and Sinopec. Equipment manufacturers such as Sunshine Hydrogen Energy, SaikeSaiSi, and Shouhang Hi-Tech are also making significant moves.

III. Limitations on the Development of Green Hydrogen

However, judging from the current state of green hydrogen development, challenges still remain.

1. The production cost of green hydrogen is high. Producing one kilogram of hydrogen requires approximately 60 kilowatt-hours of electricity. The price of “green hydrogen” is primarily linked to the cost of renewable electricity. To match the cost of “gray hydrogen,” the cost of renewable electricity per kilowatt-hour must drop below 0.2 yuan. As a result, its application is somewhat limited.

2. The transportation of green hydrogen lacks dedicated infrastructure.

3. People lack awareness of the value of green hydrogen. Currently, a market for green hydrogen has not yet been established, and there is also no internationally recognized method for distinguishing between green hydrogen and gray hydrogen. The absence of targeted goals or incentives to promote the adoption of green products also somewhat limits the downstream applications of green hydrogen.