Compact water harvester sucks H20 from the air

Developed at the University of California, Berkeley, the microwave-sized device uses fans to draw air over a cartridge containing a metal-organic framework (MOF). The MOF is so porous that a gram has the same surface area as a football pitch. Water molecules from the air are adsorbed by these internal pores, with the increasing humidity causing the H2O to condense. Heating the MOF slightly then releases the collected water.     

The MOF cartridge measures about 10 inches square and 5 inches thick. It is intersected by two sets of channels: one set for adsorbing water, the other for expelling it to the condenser, allowing continuous cycling throughout the day. Solar panels connect to batteries so that the harvester can run at night, also powering the small heaters that drive the water out of the MOF.

It’s claimed that the water harvester can produce up to 1.3 litres of water per day for every kilogram of the MOF. During field tests over three days in California's Mojave Desert, the harvester produced 0.7 litres per kilogram of absorber per day.