A humidity condenser housed in a wind turbine offers drylands a new water source.
Like most clever inventions, this one is based on a simple idea. All air contains moisture, yet few technologies can extract it efficiently. Eole Water, an innovative French company, has invented a wind turbine that does just that. It offers to revolutionise water supply in drylands (areas with low amounts of water in the soil, which make up about half of the world’s land).
Of course, this isn’t the conventional purpose of wind turbines – nor the standard design. The nacelle behind its rotors houses not just an electricity generator but also a cooling compressor, a humidity condenser (both powered by the generator) and a heat exchanger. A fan draws air into the nacelle, where it’s chilled so that its moisture condenses into water. The water is piped to the ground, mineralised and passed through filters to make it suitable for human consumption.
“A unit has been operating in the Abu Dhabi desert since November 2011, where it produces, on average, 62 litres per hour”, says Eole Water’s Thibault Janin. Janin is talking about the WMS1000 unit, powered by a 30kW turbine with a 13m diameter rotor.
It is self-contained and requires no external power source or fuel, making it ideal for areas devoid of infrastructure like deserts and islands. The nacelle stands on a 24m-high mast, where the wind is stronger and the air purer.
The company also has a variation on the theme for places with negligible wind but abundant sunshine. This one operates at ground level and is powered by solar panels. The environmental impact of either installation (once in place) is virtually zero, since the power source is wind or sunlight, the raw material is air, and all that is produced is water.
Depending on location, a single turbine installation costs between €500,000 and €600,000, and produces water for roughly $0.065 per litre over its expected 20-year lifetime.