In Rizhao, a coastal city in eastern China, engineers have built an innovative facility that turns seawater into clean drinking water and green hydrogen by reusing industrial waste heat.

 

 

 

In Rizhao, a coastal city in eastern China, engineers have built an innovative facility that turns seawater into clean drinking water and green hydrogen by reusing industrial waste heat. Instead of consuming new energy, the system captures excess heat released from nearby steel and petrochemical plants and puts it to productive use.

 

From a single input—seawater—the plant produces three valuable outputs: freshwater, hydrogen fuel, and mineral-rich brine. By combining desalination and hydrogen production in one integrated process, the system achieves far higher efficiency than conventional desalination plants, which typically discard large amounts of heat.

 

The hydrogen output alone is enough to power roughly 100 buses each year, directly linking water treatment with low-emission transportation. At the same time, the freshwater produced helps relieve stress on local water supplies in a region where demand continues to rise.

Cost is another standout feature. Operating at about 2 yuan per cubic meter, the system is cheaper than many large-scale desalination plants in countries such as Saudi Arabia and the United States. That price advantage comes largely from reusing energy that would otherwise be wasted.

 

The Rizhao project shows how industrial byproducts can be transformed into critical resources. By aligning water security, clean energy, and cost efficiency, it offers a scalable model for cities worldwide looking to redesign their water and energy infrastructure around sustainability rather than added consumption.