Indian villages can use 'solar power technology' to turn saltwater into potable water

Researchers have revealed that Indian villages could use solar power technology to turn salty water into sufficient potable water.

Around the world, there is more salty groundwater than fresh, drinkable groundwater. For example, 60 percent of India was underlain by salty water and much of that area was not served by an electric grid that could run conventional reverse-osmosis desalination plants.

MIT researchers showed that a different desalination technology called electrodialysis, powered by solar panels, could provide enough clean, palatable drinking water to supply the needs of a typical village.

The factors that point to the choice of electrodialysis in India include both relatively low levels of salinity, ranging from 500 to 3,000 milligrams per liter, compared with seawater at about 35,000 mg/L; as well as the region's lack of electrical power.

Such moderately salty water is not directly toxic, but it can have long-term effects on health, and its unpleasant taste can cause people to turn to other, dirtier water sources.

While many homes in India currently use individual, home-based filtration systems to treat their water, however, MIT graduate student Natasha Wright and Amos Winter concluded that village-scale systems would be more effective, both because fewer people would be left out of access to clean water, and because home-based systems are much harder to monitor to ensure effective water treatment.

Researchers plan to put together a working prototype for field evaluations in India in January. While this approach was initially conceived for village-scale, self-contained systems, researchers said that the same technology could also be useful for applications such as disaster relief, and for military use in remote locations.

The study is published in the journal Desalination.