COMMERCIAL SCALE SOLAR-POWERED DESALINATION

Recent studies dealing with the potential of Renewable Energy Sources (RES) for desalination along the Mediterranean Coast and in the Middle East choose to use RES to generate electricity first, and then use this electricity to power desalination. The present work eliminates the phase of electricity generation by using solar thermal energy directly for distillation by evaporation. Saving the thermal to mechanical conversion losses allows the proposed Multi Effect Distillation (MED) process to compete economically with Reverse Osmosis (RO) process of significantly lower energy consumption. The new opportunity to revive direct thermal evaporation, arises from a new collector technology developed by Solel Solar Systems, that is coupled to the familiar MED process modified by I.D.E. Technologies to match the solar steam characteristics. A combination of a large number of effects of evaporation, together with high pressure saturated solar steam available for recycling, yields a dramatic improvement in the production rate of water desalination, accompanied by relatively modest increase in the desalination installation cost. Economic considerations and technological constraints, dictate continuous operation of the desalination system while the solar radiation is limited to daytime. A heat storage capacity or fossil fuel backup is therefore essential; the optimal use of both is discussed. The study refers to a wide range of desalination capacity from a small 1000 m 3