Abu Dhabi [RenewableEnergyWorld.com] Torresol, a strategic alliance between Sener, the Spanish Engineering Group, and the Masdar Initiative in Abu Dhabi, has announced a €171 million [US $221.4 million] financing deal. Construction will now be able to go ahead on the Gemasolar plant, in Fuentes de Andalucia, just to the East of Seville, Spain. The funding has been secured though an open market, with Banco Popular, Banesto and the Instituto de Crédito Official as the lead arrangers.
The commercial-scale plant should begin operation in 2011. It will produce 17 megawatts (MW) of renewable electricity.
The technology chosen uses heliostats to focus sunlight on to a solar receiver at the top of a tower. Salts (made up of sodium and potassium nitrates) are pumped to the top of the tower whey they heat up, and return to a second tank at the base of the tower where they are stored at over 500°C. The salt then flows through heat exchangers to generate steam to drive a turbine, before being returned to the cold storage tank and then recirculated round the tower.
The use of the salts adds an element of thermal storage to the plant and allows it to operate for up to 15 hours without sunlight. The higher temperature of the salts can also lead to hotter steam at higher pressure which further increases the performance of the steam turbine.
Torresol was established in March 2008, with Sener holding 60% of the stock and Masdar the other 40%. It will aim to develop solar thermal power plants in Southern Europe, North Africa and the Middle East, and in the Southwest of the USA. It aims to do at least two plants a year and to become the leading developer of CSP in the world, doing projects on a commercial basis.
“The construction of Gemasolar represents a gigantic step forward in Torresol’s technological development…The response of the financial markets is further proof that the industry will continue to advance,” said Enrique Sendagorta, chairman of Torresol.
Comparing the power towers with the more common cylindrical-parabolic technology where the heat transfer fluid flows through the collectors Sendagorta said, “At some stage you need to start picking winners – and this technology is a winner.”
Currently the largest power tower in operation is also in Spain – Abengoa’s 10-MW PS10. Its 20-MW sibling, the PS20, is now due to begin operation in spring, Abengoa told Renewable Energy World magazine last week.