The Sahara Forest Project is a proposal to combine two innovative technologies, Concentrated Solar Power and Seawater Greenhouses, to produce renewable energy, water and food in an area of desert which is one of the hottest places on earth. Australia would seem to be another ideal location.
The Seawater Greenhouse is a process which provides water for agriculture in arid coastal regions. Concentrated Solar Power collects the sun’s energy through reflecting mirrors which are used to heat water which then produces steam to power turbines. Both technologies work best in hot, sunny areas.
The Sahara Forest Project proposes installing these systems at a location some distance from the north coast of Africa, preferably at a point below sea level which will reduce or potentially eliminate the costs of pumping seawater. The scheme has been designed as a ‘hedge’ of greenhouses providing a windbreak and shelter for the outdoor planting. Concentrated Solar Power arrays would be placed at intervals along the greenhouse ‘hedge’. The greenhouses produce five time more fresh water than needed for the plants inside. This surplus would be used to irrigate orchards and a jatrophra crop, which can be turned into bio-fuel for transportation and other needs.
Normally, in a solar thermal power plant, only about 25% of the collected solar energy is converted into electricity. In the Sahara Forest Project another 50% of the collected energy, normally released as heat, would be used for desalination.
The Project has been proposed by Charlie Paton, creator of the Seawater Greenhouse; Michael Pawlyn of Exploration Architecture and the lead architect on the iconic Eden Project; and Bill Watts of Max Fordham & Partners, an engineering firm that focuses on energy efficient systems for the built environment.