Concentrated Solar Power (CSP) is a technology which produces electricity by concentrating solar energy in a single focal point. This concentrated energy is then used to heat up a fluid, produce steam and activate turbines that produce electricity. The focusing of solar power can be achieved through different techniques such as parabolic trough, parabolic dish or power tower systems. CSP can also provide combined heat and power, particularly in desalinisation plants.CSP installations are particularly present in countries of Southern Europe, including Spain, Portugal, Italy, Greece, Malta and Cyprus. The total installed capacity by the end of 2012 is expected to up to 4GW.In the EU, after about a decade of low development, the concentrated solar thermal power sector is now expanding, notably due to a favourable supporting framework in Spain.Gemasolar is a solar plant with 19.9 MW power, located in Fuentes de Andalucía, in the region of Sevilla, Spain. Capable of supplying 110 GWh energy annually, to supply 27,500 households, it is the first commercial concentrated solar power plant with central tower receiver and molten salt storage technology. Its efficiency is significantly superior to other thermoelectric solar plants in commercial operation today, as the plant storage system allows it to continue producing electricity for 15 hours without sunlight, during the night or cloudy weather. Thanks to this storage capacity, solar energy becomes capable of responding to the grid's demand. Concentrated solar power uses direct solar radiation: mirrors concentrate the sun's rays at a point around which fluid is circulating. In turn, the heat in this fluid is used to generate steam, which turns a turbine. In Gemasolar plant, this hot fluid not only generates steam, but it also stores surplus heat in tanks containing molten nitrate salts. The solar field is composed of 2,650 heliostats, distributed in concentric rings around the tower, with the furthest heliostat approximately 1 km from the tower. Each heliostat consists of a 120 m2 reflective surface, which is continually repositioned throughout the day, depending on the position of the sun and the weather conditions. The Gemasolar receiver is capable of absorbing 95% of radiation in the solar spectrum and of transmitting this energy to the molten salt compound that circulates in its interior.