Scientists have developed a new solar-powered system to convert saltwater into fresh drinking water which they say could help reduce dangerous the risk of waterborne diseases like cholera.

Via tests in rural communities, they showed that the process is more than 20% cheaper than traditional methods and can be deployed in rural locations around the globe.

Building on existing processes that convert saline groundwater to freshwater, the researchers from King's College London, in collaboration with MIT and the Helmholtz Institute for Renewable Energy Systems, created a new system that produced consistent levels of water using solar power, and reported it in a paper published recently in Nature Water

It works through a process called electrodialysis which separates the salt using a set of specialized membranes that channel salt ions into a stream of brine, leaving the water fresh and drinkable. By flexibly adjusting the voltage and the rate at which salt water flowed through the system, the researchers developed a system that adjusts to variable sunshine while not compromising on the amount of fresh drinking water produced.

Using data first gathered in the village of Chelleru near Hyderabad in India, and then recreating these conditions of the village in New Mexico, the team successfully converted up to 10 cubic meters, or several bathtubs worth of fresh drinking water. This was enough for 3,000 people a day with the process continuing to run regardless of variable solar power caused by cloud coverage and rain.

Dr. Wei He from the Department of Engineering at King's College London believes the new technology could bring massive benefits to rural communities, not only increasing the supply of drinking water but also bringing health benefits.

"By offering a cheap, eco-friendly alternative that can be operated off the grid, our technology enables communities to tap into alternative water sources (such as deep aquifers or saline water) to address water scarcity and contamination in traditional water supplies," said He.

"This technology can expand water sources available to communities beyond traditional ones and by providing water from uncontaminated saline sources, may help combat water scarcity or unexpected emergencies when conventional water supplies are disrupted, for example like the recent cholera outbreaks in Zambia."

In the global rural population, 1.6 billion people face water scarcity, many of whom are reliant on stressed reserves of groundwater lying beneath the Earth's surface.

However, worldwide 56% of groundwater is saline and unsuitable for consumption. This issue is particularly prevalent in India, where 60% of the land harbors undrinkable saline water. Consequently, there is a pressing need for efficient desalination methods to create fresh drinking water cheaply, and at scale.

Traditional desalination technology has relied either on costly batteries in off-grid systems or a grid system to supply the energy necessary to remove salt from the water. In developing countries' rural areas, however, grid infrastructure can be unreliable and is largely reliant on fossil fuels.

Creating a low-cost ‘battery-like' desalination technology removes the reliance on battery technology for using intermittent solar energy in off-grid applications, enabling affordability to rural communities in developing countries like India.

"By removing the need for a grid system entirely and cutting reliance on battery tech by 92%, our system can provide reliable access to safe drinking water, entirely emission-free, onsite, and at a discount of roughly 22% to the people who need it compared to traditional methods," He said.

The system also has the potential to be used outside of developing areas, particularly in agriculture where climate change is leading to unstable reserves of fresh water for irrigation.

The team plans to scale up the availability of the technology across India through collaboration with local partners. Beyond this, a team from MIT also plans to create a start-up to commercialize and fund the technology.

"While the US and UK have more stable, diversified grids than most countries, they still rely on fossil fuels. By removing fossil fuels from the equation for energy-hungry sectors like agriculture, we can help accelerate the transition to Net Zero," He said.

"The next step for us is to apply this low-cost technology to other sectors, including wastewater treatment, and producing alkaline to make the ocean more alkaline to help it absorb more CO2 from the atmosphere. By taking this approach not only can we decarbonize agriculture, but wider environmental and climate benefits as well."

SHARE This Invention That Could Change The World On Social Media…