China has launched a new desalination facility in Shandong that converts seawater into ultra-pure fresh water at a cost of just two yuan per cubic metre, making it cheaper than many sources of tap water. At the same time, the plant generates green hydrogen as a by-product along with mineral-rich brine for industrial use. Located in the coastal city of Rizhao, the project demonstrates how an integrated water and energy system can deliver both economic and environmental benefits in resource-constrained regions.

The facility operates using seawater alone and relies on low-grade waste heat from nearby steel and petrochemical plants. This eliminates the need for freshwater inputs and reduces typical desalination costs. During its first three weeks of continuous operation, the plant successfully produced both clean water and hydrogen, signalling a significant advancement in sustainable industrial systems. Its early performance shows how circular models can enhance energy resilience and improve the efficiency of water-intensive processes.

One-In, three-out circular economy model

Data from the project shows that processing 800 tonnes of seawater annually can yield 450 cubic metres of ultra-pure water, 192,000 standard cubic metres of green hydrogen and 350 tonnes of mineral-rich brine. This transforms a single resource stream into three valuable outputs, minimising waste and maximising resource productivity. The hydrogen produced is sufficient to power up to 100 buses for 3,840 kilometres each year, demonstrating the practical mobility potential of hydrogen derived from seawater.

The plant’s energy requirement is relatively low at roughly 4.2 kilowatt-hours per cubic metre of hydrogen produced. This contributes to its economic viability and strengthens the case for replicating similar models in coastal or water-stressed regions that have access to waste heat sources.

If deployed at scale, this integrated seawater-to-water-and-hydrogen system could serve as a blueprint for sustainable development worldwide. By combining desalination, green hydrogen generation and by-product utilisation into a single process, the facility showcases how circular approaches can support industrial decarbonisation, enhance water security and contribute to cleaner energy systems in the years ahead.

Source:
https://www.scmp.com/news/china/science/article/3335518/chinese-desalination-plant-makes-fresh-water-cheaper-tap-water-plus-green-hydrogen