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This Water Harvester Can Pull Water Out Of Thin Air

A new paper for the Journal of the American Chemical Society explains a device that is capable of turning thin air into water. The device, called water harvester, comes from a team of researchers from the University of California, Berkeley.

The water harvester can collect more than five cups of water from low-humidity air per day per 2.2 pounds of water-absorbing materials. These, known as metal-organic frameworks, are porous. This means that you will be able to produce enough water to live for a day. As per the World Health Organization, you would actually have a surplus.

Eugene Kapustin, a Ph.D. student at UC Berkeley, said in a YouTube video that was released by the university, ‘What it does is collect water from the atmosphere to very dry conditions and then releases it so we can harvest it as liquid water.’ The highlight of the process is the metal organic framework that is basically a pile of powder that is full of organic molecules and metals. The mixture is left out, overnight, thus allowing it to collect water molecules that are present in the atmosphere. These water molecules are able to attach themselves to the metal organic framework. Kapustin said, ‘You can imagine it’s like a sponge.’

The mixture is placed in a water-tight tank and warmed using heat lamps when it is time to extract water. Droplets of water end up clinging to the sides and are eventually collected as pure H2O. The scientists are studying this topic because of the scarcity of water around the world. The team is close to creating a microwave-sized water harvester that you could use for pulling water of the air. The harvest was cycled 24.7 during a three-day field test carried out in California’s Mojave Desert and relied on solar panels and a battery for its power. The device was capable of creating almost three cups of pure H2O.

Omar Yaghi, the principal researcher, said in a prepared statement, ‘It is well known that in order to condense water from air at a low humidity—less than 40 percent relative humidity—you need to cool down the air to below freezing, to zero degrees Celsius, which is impractical. With our harvester, we are doing this at very low humidity without such cooling; there is no other material that can do that,” says Yaghi, who is also a UC Berkeley professor of chemistry. “This is not like a dehumidifier, which operates at high relative humidity. Some people say that 0.7 liters are not a lot of water. But it is a lot of water if you don’t have water.’

The startup for this project, Water Harvester Inc., will be commencing marketing for this device soon enough capable of creating 7-10 liters of water every day. Another version of the device, comparable in size to a small refrigerator, will produce 200-250 liters of water every day. Yaghi also said, ‘This water mobility is not only critical to those suffering from water stress but also makes possible the larger objective—that water should be a human right.’