Solar Thermal Processes

Abstract

The use of solar energy for desalination purposes was one of the first processes developed for producing fresh water from salt water. The process is based on the use of solar thermal energy to evaporate water, thus separating pure water from brine. In this chapter an overview of solar thermal desalination processes is presented. The first sections introduce the use of the simplest devices, i.e. solar stills, as stand alone systems or integrated into more complex geometries such as greenhouses. Couplings of the most recent technologies for solar thermal energy collectors with conventional thermal desalination processes are then presented. In all cases, a study of the feasibility and potential for further developments are presented. Solar thermal systems seem to be a very good option in remote areas with high insolation and where the use of conventional energy sources for desalination is not a viable option. Moreover the rising energy cost and continuous improvements of solar technologies are making such technologies more and more competitive compared with conventional ones.