Yet another new technique.
Simple, solar-powered water desalination
A completely passive solar-powered desalination system developed by researchers at MIT and in China
could provide more than 1.5 gallons of fresh drinking water
per hour for every square meter of solar
collecting area. Such systems could potentially serve off-grid arid coastal areas to provide an efficient, low-cost water
The system uses multiple layers of flat solar
evaporators and condensers, lined up in a vertical array and topped with transparent aerogel insulation
. It is described in a paper
appearing today in the journal Energy and Environmental Science
The key to the systemís efficiency lies in the way it uses each of the multiple stages to desalinate the water
. At each stage, heat released by the previous stage is harnessed instead of wasted. In this way, the teamís demonstration device can achieve an overall efficiency of 385 percent in converting the energy of sunlight into the energy of water evaporation.