In the World: Small Mexican village produces clean water with solar-powered system
In a small village deep in the jungles of the Yucatan Peninsula — a day’s drive from any source of clean, drinkable water — researchers from MIT are testing a system that purifies water with the help of the sun. The relatively inexpensive system consists of several modest photovoltaic panels, a large tank to hold purified water, and a telephone booth-sized shed that houses the heart of the system: pumps, filters and membranes, and computers that enable the system to run itself. The solar panels, programmed to maximize the capture of sunlight, power the system’s pumps to push brown, brackish well water through semiporous membranes — a process known as reverse osmosis. The membranes filter clean, drinkable water into a large tank, leaving behind salts and other heavy minerals. Even on a cloudy day, the solar-powered setup can produce about 1,000 liters of drinking water — enough to supply the...