Fast Co: New device can pull drinking water from air for just .02 cents/liter

The new system, called WEDEW (“wood-to-energy deployed water”) was created by combining two existing systems. One is a device called Skywater, a large box that mimics the way clouds are formed: It takes in warm air, which hits cold air and forms droplets of condensation that can be used as pure drinking water. The water is stored in a tank inside the shipping container, which can then be connected to a bottle refill station or a tap.

Because the process uses a large amount of electricity, designers paired it with a biomass gassifier, a low-cost source of energy. When the gassifier is filled with wood chips, coconut shells, or whatever biomass is locally available, a process calls pyrolysis vaporizes that material. That makes the system hot and humid, the ideal environment to run the air-to-water machine. As it generates power, it also produces biochar, a charcoal that can be added to soil to store carbon and help plants grow.

“It’s a carbon-negative technology,” says David Hertz, a California-based architect who helped lead the project.

In a place like California, the gassifier could be fed with pine trees that have been killed by years of drought and pests. Left in forests, the dead trees are at risk of burning in fires and releasing CO2. In the machine, the carbon in the wood could be captured and added to soil as the system creates fresh water.

In parts of the world where wood is less available, the system could also run on solar and battery power rather than biomass.