By mounting a water distillation system on the back of a solar cell, engineers have constructed a device that doubles as an energy generator and water purifier.
While the solar cell harvests sunlight for electricity, heat from the solar panel drives evaporation in the water distiller below. That vapor wafts through a porous polystyrene membrane that filters out salt and other contaminants, allowing clean water to condense on the other side. “It doesnt affect the electricity production by the [solar cell]. And at the same time, it gives you bonus freshwater,” says study coauthor Peng Wang, an engineer at King Abdullah University of Science and Technology in Thuwal, Saudi Arabia.
Solar farms that install these two-for-one machines could help meet the increasing global demand for freshwater while cranking out electricity, researchers report online July 9 in Nature Communications.
Using this kind of technology to tackle two big challenges at once “is a great idea,” says Jun Zhou, a materials scientist at Huazhong University of Science and Technology in Wuhan, China not involved in the work.
In lab experiments under a lamp whose illumination mimics the sun, a prototype device converted about 11 percent of incoming light into electricity. Thats comparable to commercial solar cells, which usually transform some 10 to 20 percent of the sunlight they soak up into usable energy (SN: 8/5/17, p. 22). The researchers tested how well their prototype purified water by feeding saltwater and dirty water laced with heavy metals into the distiller. Based on those experiments, a device about a meter across is esRead More – Source