Seawater desalination is one of the possible solutions to the severe water shortage problem our planet is experiencing during the first half of this century, a problem that is not exclusive to developing countries, as the appearance of seasonal episodes of persistent drought in certain regions of the so-called developed countries is becoming more and more frequent. Despite the energy efficiency advances reached during the last decade, seawater desalination continues to be an intensive fossil energy consumer. In the current global framework, with growing oil price instability and the environmental requirements derived from compliance with the Kyoto Protocol, the sustainability of this technological solution inevitably passes through continued improvement of energy efficiency of the physical processes involved, as well as the use of renewable energy resources, such as for example, solar energy.

In 2002, a new combined (research & demonstration) project called Enhanced Zero Discharge Seawater Desalination using Hybrid Solar Technology (AQUASOL) was initiated. The main objective of this project is the development of a seawater desalination technology based on multi-effect distillation that is energy efficient, low-cost and has a zero discharge. In August 2004, the AQUASOL Project research phase was successfully concluded and all the subsystems have been designed and implemented for their evaluation during the demonstration phase. The desalination system developed combines the use of solar static collectors and the absorption heat pump technology, in order to increase the overall efficiency of the process. This paper describes the final design of the overall system, and all erection works performed.