Transforming The Sahara Landscape

Last week, a trio of visionaries, Charlies Patton, Bill Watts and Micheal Pawlyn unveiled their ambitious plan for the Sahara Desert. The project seeks to produce enough water to grow crops, produce a sustainable bio-fuel that does not negatively impact world food supplies and harness enough solar power to supply electricity to cities in Africa and Europe by redefining some of the desert landscape.

As we know, no one solution will successfully address global warming and all the numerous issues that go with it such as shortage in water supply and increasing food prices. The Sahara Forest Project seeks to combine technologies by marrying greenhouses with concentrated solar power (CSP) which uses mirrors to focus the sun's rays and generate heat and electricity. The installations would transform patches of the vast desert into lush vegetation without the traditional system of digging wells for fresh water, which has depleted many aquifers around the world.

Plants cannot naturally grow in arid climates so the greenhouses work by using the solar farm to power seawater evaporators and then pump the cool damp air throughout the greenhouse. This reduces the temperature within by about 20 deg Celsius compared to that outside and at the other end of the greenhouse, the water vapor is condensed creating situations of high humidity and lower temperature.

According to the designers, virtually any vegetable could be grown here, depending on the specific conditions at which it is maintained as demonstrations have already produced lettuce, cucumbers, tomatoes and peppers with the necessary nutrients for the plants coming from the seawater itself.

Charles Patton reports that the greenhouse would produce more than five times the fresh water needed for the plants so the rest could be utilized by the local environment and the same goes for the excess solar power generated.

The cost of the Sahara Forest Project will be relatively cheap as both CSP and seawater greenhouses are already proven technologies so estimates for a 20 hecter greenhouse combined with a 10MW CSP scheme would come to about $130 million or 80 million euros.

This sounds like a good idea but I'm not sure just how much food or electricity could be produced on a 20 hecter greenhouse to really counterbalance the high cost of food or equally high demand for energy around the world as the designers claim. Will the 20 hecters be enough or will the entire face of the Sahara have to be similarly changed eventually and what will that do to the ecosystem and environment?


Image obtained from www.Guardian.co.uk