Many hydric-stressed countries should be prepared to face the fresh water scarcity when the water/energy nexus is being tighter year after year. Scientific and technological development is rapidly progressing; conventional processes are becoming more and more efficient and cost effective and novel desalination technologies are emerging. The first part of this paper is an overview on the current state of the worldwide desalination and the recent development in desalination powered by renewable energy sources. We focus on the progress made in the integration of the geothermal water as energy input for thermal desalination processes. In the second part, we inventory the Tunisian desalination status by exploring the conventional desalination plants and those driven by geothermal energy. Thermal waters having temperatures between 30 and 80°C characterize the geothermal potential of the southern Tunisia. The technical properties of the local existing wells promote the feasibility of geothermal brackish water desalination based on multi-effect distillation process.
Using the SWOT analysis tool, we prove that geothermal energy is appropriate to supply remote communities of the southern Tunisia in fresh water. Moreover, it is environmentally friendly and economically competitive. Geothermal energy, when it is available with sufficient enthalpy, is best suited to continuous thermal desalination.
Desalination, geothermal, brackish water, MED, potential, remote regions
