MIT researcher develops solar-powered desalination technology

A student at Massachusetts Institute of Technology (MIT) has designed a village-scale desalination technology that is powered by the sun and can turn saline water palatable by removing its salty taste.

MIT Mechanical Engineering PhD student Natasha Wright worked for the project over three years to come up with the technology, which initially focused on filtering biological contaminants from groundwater to make it potable.

She joined MIT Mechanical Engineering assistant professor Amos Winter’s laboratory in 2012, and started working on the project.

The solar-powered technology uses electrodialysis, which uses electric potential to extract salt from the water.

The ultraviolet light from the sun rays are used to kill biological contaminants in the water.

While similar desalination technologies have already been discovered, none of the available filters were able to remove the saltiness of the water post-treatment.

During her visits to rural India for the project, Wright found desalination devices were not much use to villagers. Such devices, though purified the water, could not eliminate its salty taste.

Wright said: "The biggest surprise of the project so far has been this salt issue, which was the thing that changed the entire purpose of the research."

As a part of the project, the researcher aims to develop a cost-effective system, which will have a capacity to offer potable desalinated water for 5,000 people.

Wright and her research team have received a US Agency for International Development (USAID) grant for testing the system at full-scale for the first time in New Mexico earlier in the year.

A pilot for the project is also likely to be tested in India this year following a second stage of the USAID grant.

Wright said: "It’s useful to install a small-scale desalination system where people are so spread out that it’s more costly to pump in water from a municipal plant.

"That’s true in India and that’s also true in the US."