Water scientists and researchers are reaching new heights in the search for new water resources. Scientists in the United States have created a new device that harvests water directly from the air in arid regions. It is said to be powered entirely by sunlight.

According to an article in the journal Science, the water harvester has the capacity to extract 2.8litres of water from air in 12 hours and is also effective at low humidity levels.

The prototype was developed by Omar Yaghi and Evelyn Wang.

Yaghi said this was a “major breakthrough” in the long-standing challenge of harvesting water from the air at low humidity.

“This is the first device capable of water capture and delivery under conditions typical of arid regions, making it possible to water those areas,” Yaghi said. He is also affiliated with the King Abdullah University of Science and Technology in Saudi Arabia.

Design

The prototype uses a metal-organic framework which combines metals such as magnesium or aluminium with organic molecules to create rigid, porous structures ideal for storing gases and liquids.

As air diffuses through the framework, water molecules attach to the interior surfaces. When sunlight heats the framework, water is driven towards the condenser. The water vapour then condenses and drips into a container where it collects.

Yaghi told the journal that he hopes the water harvester will be commercialised in a few years, and added that this was just the first step towards his grander vision.

“I’d like to see water off-grid, where you have a device at home running on ambient sunlight and delivering water that satisfies the needs of a household,” he said.