Water is everywhere, but there’s hardly a drop to drink. The vast majority of the Earth’s surface is either arid or salty ocean. Only 2.5% of our planet’s water resources are fresh, and just a tiny tiny fraction (0.007%) of that is available for direct human use.
Yet one of the largest sources of water is around us every day: the air. Even our deserts are awash in moist air. Israel’s Negev hits an annual average relative humidity of 64%. That translates into 1.2 centimeters of water for every cubic meter of air.
The problem, of course, is that it’s rarely moist enough to rain. Scientists have spent decades exploring ways to convert this water vapor into water for drinking or crops. Such trials include fog nets, as well as solar-powered brine pumps to suck moisture from the air. None have gained widespread adoption.
Now a French company, Eole Water, has successfully tested a wind turbine as a source of fresh water and renewable energy. Field trials in Abu Dhabi are yielding 132 to 211 gallons daily, and the company’s marketing director Thibault Janin says in the magazine Recharge that "the results have been very good." The results "would be even better, of course, if it was placed in coastal or offshore areas where there is higher humidity and more wind."
Resembling a conventional wind turbine, Eole’s nacelle actually houses a compressor, water condensers, and heating devices. The turbine heats the air before it is condensed to extract and siphon off the moisture into tanks where it is treated. The hot air is simply blown out of vents, and surplus electricity sent to the grid.
The technology, under development for a decade, has already attracted interest from a host of major companies such as Siemens and Danfoss. The companies are keen on selling solutions to the millions of communities around the world that remain without clean water, as well as the ones that are confronting water shortages in the future.
Hat tip: SmartPlanet