Desalination of sea and brackish water is today a normal technique to alleviate the increasing shortage of clear water in many areas of the world. Nonetheless, desalination processes require large quantities of energy, so their implementation is jeopardized by a significant environmental impact if fossil fuels are used; in addition, the cost of the different desalination techniques is very closely linked to the costs of energy. Therefore, in a context where the energy costs are continuously rising and with the impending exhaustion of the conventional energy resources, the development of desalination technologies associated to the use of renewable energies is a very attractive and promising prospect.