China has completed its largest offshore project, which combines solar power, hydrogen production, and energy storage. This marks a big step in the country’s efforts to create more reliable renewable energy systems. The project, off the coast of Rudong in East China’s Jiangsu Province, was reported as completed on Wednesday, according to China Media Group.
Funded by CHN Energy Guohua Energy Investment Co., the facility is described as China’s largest offshore solar demonstration project that combines solar power, hydrogen production, and energy storage.
Massive offshore facility combines multiple energy technologies
The Rudong project features 400,000 kilowatts (400 MW) of solar capacity and a new 220-kilovolt onshore booster station. It also includes a hydrogen production station capable of producing 1,500 standard cubic meters of hydrogen per hour, along with an electrochemical energy storage station.
According to Chinese media reports, this is the first project in China to combine power generation, hydrogen production, energy storage, full energy use, and coastal ecological management in one development.
The facility has been designed around what officials describe as an integrated “electricity-storage-hydrogen” model. Solar power made offshore can go to the grid, be stored in batteries, or be used to make hydrogen from water. This setup lets energy be used in different ways based on demand and conditions.
The project is built on coastal tidal flats, which are often considered suitable sites for large renewable energy projects. It also uses advanced solar technology and smart control systems to improve energy conversion and management.
Green hydrogen plays a central role
One important feature of the project is that it can make green hydrogen using electricity from renewable sources. By using solar power to split water into hydrogen and oxygen, the facility can store energy as hydrogen for later use.
The Nantong Daily reported earlier this year that the solar power station achieved full-capacity grid connection on April 29, 2025. When the whole project is running, the energy storage station will be able to supply 120,000 kilowatt-hours of electricity during peak demand each day.
Meanwhile, the hydrogen production facility is expected to generate up to 180 tons of green hydrogen each year. This hydrogen can be used by nearby industries, such as chemical manufacturing and transportation, that are looking for cleaner fuel options.
Officials say the finished solar, hydrogen, and storage facilities will operate as a closed-loop energy system covering generation, storage, use, and backup.
Experts highlight stability advantages
Lin Boqiang, director of the China Center for Energy Economics Research at Xiamen University, said that adding hydrogen and storage technologies can help address the problem of solar power’s volatility. He said the project shows that renewable energy is moving beyond just adding more power generation.
“Its completion marks a further step forward for China in the field of new-energy multi-energy complementarity,” he stated. He added that the project is now focused on energy conversion efficiency, integrating different energy sources, and making the system more stable, rather than just increasing capacity.
He also said that coastal regions often have strong wind and solar resources but still face inconsistent energy supply.
China scales up renewable hydrogen production
This project comes as China is rapidly expanding hydrogen production from renewable energy across the country. The National Energy Administration says the industry is moving from pilot projects to large-scale commercial use.
As of the end of March, completed and ongoing renewable hydrogen projects in China had a total production capacity of over 1 million tons per year. More than 250,000 tons per year are already in operation, which is more than double the capacity at the end of 2024. Projects under construction will add over 900,000 tons of annual capacity.
Lin noted that the long-term value of projects like Rudong will depend on reducing development costs and improving the efficiency of hydrogen production. Still, the new facility is one of the best examples to date of how solar power, energy storage, and hydrogen production can work together in a large-scale clean energy system.
