During Abu Dhabi’s World Future Energy Summit, Torresol Energy announced that it has secured a EUR 171 million (US$221 million) financing deal to allow construction to begin on Gemasolar, the world’s first utility grade solar power plant with central tower and salt receiver technology. With this operation, Torresol now has the entire €240 million (US$309 million) it needs to build the plant, located in Fuentes de Andalucia, Seville.
Funding was secured through the open market with Banco Popular, Banesto and the Instituto de Credito Oficial acting as mandated lead arrangers.
The Gemasolar plant will be operational in 2011 and produce around 17 MW of energy a year. The project is the first to use central tower and salt receiver technology in a commercial environment, as an alternative to cylindrical-parabolic commercial solar thermal plants.
An engineering, procurement and construction contract has been awarded to a consortium, including SENER and Spanish engineering company AMSA (part of ACS Cobra Group). In the consortium, SENER will be in charge of providing the technology, the detail design and commissioning of the plant. The technology chosen uses heliostats to focus sunlight on to a solar receiver at the top of a tower. This receiver is able to absorb 95 percent of the radiation from the sun’s spectrum and transmit the energy to the salt compound circulating within the receiver. SENER will also provide its trademark Sensol software for sizing and optimizing the plant and the thermal molten salts storage system.
The Gemasolar plant technology is expected to treble the electricity production from a traditional thermoelectric solar plant. The majority of thermoelectric plants don’t yet have a thermal storage system, while Gemasolar’s high temperature heat storage extends the normal operating period of solar plants, giving it 15 hours of autonomy without sunlight.
Salts, made up of sodium and potassium nitrates, are kept molten using solar energy collected from the heliostats. Excess accumulated heat is stored while the sun shines, making it possible to produce electricity even when there is not enough solar radiation. The high temperature at which the solar energy is captured in the salt receiver (over 500 degrees centigrade) also allows more pressurized and hotter steam, increasing the steam turbine’s performance.
SENER is working in four different thermosolar (or CSP) projects in Spain. Two of them are in Granada (Andalusia): Andasol 1, in operation, and Andasol 2, currently being built, in a consortium with ACS-Cobra, and two other plants, Extresol 1 and 2, are being built in Extremadura.
It opened an office in San Francisco last year to actively explore opportunities for CSP plants in the Southwest of the United States.