A new solar desalination system with heat recovery for decentralised drinking water production

A new solar thermal desalination system has been developed and tested in field conditions. The system has two components: a desalination tower with multiple stages and one or more solar collectors. Sea and ground water can be used to feed the desalination tower, which produces desalinated and decontaminated water in its 5–7 horizontal stages. The solar collectors are used to absorb solar energy and a fluid, the desalinated water itself, transports the heat energy to the tower. Four different systems have been tested in Germany, Spain, India, and Brazil. The field tests show some important results: the system produces about 15–18 L/m2/day, which represents a factor of 5–6 times higher than the production of a still type distiller; it is modular and each unit produces approximately 35 L/day that allows the installation of larger systems (1000–2000 L/day).

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