Water and power
Desalination plants play a vital role in arid regions such as the Middle East, but the process is extremely energy intensive and expensive. Meanwhile in water-short China, laws require that new power plants must provide their own freshwater. Tackling both problems, an Israeli firm recently built an innovative desalination plant in the Hangu district of Tianjin, to supply water to power the steam boilers in a nearby state-run power plant. The desalination process is powered by waste heat from the power plant. Seawater is heated with steam, then evaporated to produce freshwater and table salt. Some 20 per cent of the plant’s daily 200,000 cubic-metre freshwater output is used in the power plant’s steam boilers, and the rest provides drinking water to the local population, as mandated by law.