How to get fresh water out of thin air

Fog-harvesting system developed by MIT and Chilean researchers could provide potable water for the world's driest regions. In some of this planet's driest regions, where rainfall is rare or even nonexistent, a few specialized plants and insects have devised ingenious strategies to provide themselves with the water necessary for life: They pull it right out of the air, from fog that drifts in from warm oceans nearby. Now researchers at MIT, working in collaboration with colleagues in Chile, are seeking to mimic that trick on a much larger scale, potentially supplying significant quantities of clean, potable water in places where there are few alternatives. Fog harvesting, as the technique is known, is not a new idea: Systems to make use of this airborne potable water already exist in at least 17 nations. But the new research shows that their efficiency in a mild fog condition can be improved by at least fivefold, making them far more feasible and practical than existing versions. The new findings have just been published online by the journal Langmuir , a publication of the American Chemical Society, in a paper by MIT postdoc Kyoo-Chul Park PhD '13, MIT alumnus Shreerang Chhatre PhD '13, graduate student Siddarth Srinivasan, chemical engineering professor Robert Cohen, and mechanical engineering professor Gareth McKinley. Fog-harvesting systems generally consist of a vertical mesh, sort of like an oversized tennis net.