In the Chinese city of Rizhao, a facility has begun operation that combines seawater desalination and the production of green hydrogen. It is one of the first projects in which desalination and green hydrogen production are integrated into a single industrial ecosystem using waste heat.
The technology is based on electrolysis — the splitting of water by electric current. To reduce costs, the facility uses heat from a nearby steel plant. This approach helps reduce energy losses and lower the carbon footprint at the same time.
In one cycle, 800 tons of seawater are processed. The plant produces about 450 tons of drinking water, 192,000 cubic meters of green hydrogen and 350 tons of mineral brine for the chemical industry. The amount of hydrogen produced is enough to power 50 city buses on routes totaling about 7,400 kilometers without emissions.
Until recently, desalination was seen as an expensive and energy-intensive solution, while green hydrogen was viewed as a technology of the future requiring large-scale subsidies. The Rizhao project addresses two global challenges — the growing shortage of fresh water and the need to decarbonize the economy. Coastal cities may thus gain a chance not only to secure their own water supply, but also to produce fuel from the same sea.
