It is reported that, a team of researchers led by the Massachusetts Institute of Technology (MIT) has developed a
device that can convert seawater into drinking water,
This device, inspired by the ocean, is solar-powered.
In a recent paper published in the journal Joule, the team outlines the design of a new solar-powered seawater desalination system that can absorb seawater and heat it using natural sunlight.
Most importantly, this desalination device is more efficient, durable, and cheaper than previous desalination devices.
Desalination is the process of removing salt from saltwater, so that after desalination, seawater can be drunk.
Compared to all other passive solar seawater desalination concepts currently being tested, the new system has higher water production and higher salt rejection rates.
Moreover, this new device relies only on solar energy, which means users do not have to consider electricity costs during desalination.
Specifically, the structure of the device allows water to circulate in a vortex, similar to the larger "thermohaline" circulation in the ocean. This circulation, coupled with the heat of the sun, drives water evaporation, leaving behind the salt.
The resulting water vapor can be condensed and collected as pure drinking water. Meanwhile, the remaining salt continues to circulate in and out of the device, rather than accumulating and clogging the system.
Researchers estimate that if the system is scaled up to the size of a small suitcase, it can produce about 4 to 6 liters of drinking water per hour, and components only need to be replaced after several years of use.
At this scale and performance, the system produces drinking water at a lower cost and faster than tap water.
"After several years of operation, the cost of water produced by our system may be lower than the price of tap water. And this is the first time that water produced by sunlight may be cheaper than tap water." said the researchers.
The team envisions that a scaled-up device could passively produce enough drinking water to meet the daily needs of a small family.
The system could also supply off-grid coastal communities where seawater is readily available.
