Central Solar Tower and Heliostat System Stores Heat Energy in Molten Salt

GEMASOLAR is the first Torresol Energy project to be developed with central tower and heliostat technology. The plant incorporates significant technological innovations, among which is the solar collection system, but there is also a molten-salt heat storage system that is capable of attaining temperatures exceeding 500ºC.
This is the first commercial-scale plant in the world to apply this type of technology, with its relevance lying in this singular method, which is opening the way forward for a new thermosolar electricity generation technology. GEMASOLAR, which is the flagship project of the company Torresol Energy, will be capable of providing 30,000 homes with safe, clean energy and also reduce CO2emissions by over 40,000 tons per year.
The GEMASOLAR plant commenced construction in 2008 in Fuentes de Andalucía, Seville. It is an installation that will have 2,500 heliostats occupying 185 hectares and, once in operation, will have 17 MW of generating power. The power generated by GEMASOLAR of approximately 110 GWh/year shall be sent over a high-voltage line to the Villanueva del Rey (Andalusia, Spain) substation, where it shall injected into the grid to provide electricity for 30.000 homes.
Most thermosolar plants currently under development lack energy storage and can only operate during hours of sunlight. For the first time, GEMASOLAR has an innovating high-temperature molten-salt heat storage system that allows the normal operating period of these plants to be extended. The heat collected by the salt is used to produce steam and thus generate electricity. The surplus heat, which is accumulated during the hours of sunlight, is stored in the hot tank. This enables electricity generation to continue, even in darkness when there is no sunlight.
The extension of plant operating time during the absence of sunlight, together with enhanced efficiency in the use of the sun’s heat means that the GEMASOLAR production is three times that attained by other technologies in installations having the same power.