A new seawater desalination plant in the coastal Chinese city of Rizhao has achieved what many considered impossible, producing green hydrogen fuel, with fresh water costing just 28 cents per cubic meter compared to Saudi Arabia’s 56 cents and California’s $2.20. For every 800 metric tons of seawater processed, the system delivers 118,877 gallons of pure fresh water, 192,000 standard cubic meters of green hydrogen fuel enough to power 50 city buses for around 4,600 zero emission miles each, and 350 metric tons of mineral-rich brine sold for marine chemical production instead of being dumped as toxic waste. Rizhao, whose name literally means sunshine, is one of China’s most renewably powered cities where all urban water heaters run on solar panels and which was ranked by the UN as one of the most habitable cities in the world.
Desalination has long been held back by massive energy consumption leaving large carbon footprints, the need to de-scale membranes with chemicals toxic to sea life, and the challenge of disposing of overly salty brine that acts as an ecological contaminant, but the Rizhao facility solves all these problems simultaneously. Senior engineer Qin Jiangguang told reporters this opens a new path for extracting energy from the sea, with the waste heat utilization being a focus of Chinese industrial policy given the country’s extensive coastlines and abundance of industrial facilities. The breakthrough represents a watershed moment for an industry struggling with fundamental difficulties in turning seawater into pure water economically. The success could pave the way for similar installations worldwide, particularly in regions facing water scarcity and looking for sustainable solutions that produce both fresh water and clean energy while turning waste products into profitable materials.
