Aug 11 2011
From the first of May 2011, the commercial operation for the power plant, the first commercial plant in the world to use molten salt storage in a central tower configuration with a heliostat field, yielded better results than were expected. With its 19.9 MW of power, Gemasolar reached peak production levels of over 350 MWh in 24 hours of uninterrupted operation.
Thanks to its storage capacity in July, Gemasolar was able to supply energy during the hours of highest demand in Spain: 12 pm and 10 pm. The highest demand in Spain has two peaks. One is produced in the day. The second one, in general the strongest, is produced just after sunset. The forecast for August is that Gemasolar will continue the upward trend it has maintained since its entry into operation last May.
Gemasolar, the world's first commercial high temperature solar plant, capable of reaching more than 500 ºC degrees, to enter into commercial operation, boasts a storage capacity of 15 hours. That storage capacity makes it possible for it to supply energy to the grid based on demand, regardless of whether there is constant solar radiation. With this project, Torresol Energy has made generating dispatchable power from renewable energy sources a reality.
It is expected that Gemasolar will produce a net total of over 110,000 MWh per year by operating for a total of 6450 hours a year at full capacity. The summer months are when the plant is at its greatest efficiency; therefore, Torresol Energy's technicians estimate that come mid-September, its equivalent average production time will be 18 hours at full capacity per day.
The Gemasolar plant, located in Fuentes de Andalucía (Seville), is a property of Torresol Energy, a joint venture between the engineering and technology group SENER, and Masdar, Abu Dhabi’s multi-faceted renewable energy initiative. SENER has been responsible for supplying all of the technology for Gemasolar, the engineering detail design and for leading the EPC and commissioning works of the plant. As for Masdar, a strategic developer of renewable energy power projects, the company is proud of the commercial approach they have taken to funding and operating this facility.
Felicia Bellows, Executive Vice President of Development for Torresol Energy U.S.A., explains: "Currently we are the only company in the world that is commissioning a commercial central tower project with molten salt receiver capable of absorbing 90% of the solar radiation. Gemasolar is Torresol Energy's flagship project because of its innovative technology, and in the short term we expect to be able to develop similar plants on the South West Coast of the U.S., where there are optimal levels of solar irradiation."
Frank Wouters, the director of Masdar Power, said: “The first months of Gemasolar’s operation have exceeded expectations. Masdar Power believes in introducing and launching new technologies in the clean energy spectrum, and we will continue to explore fresh opportunities to implement such novel technologies that will bring multiple benefits to the community.”
Mercedes Sierra, Vice President of SENER office in the US, adds: "The efficiency of this technology, which is developed by SENER, is proving to be vastly superior to conventional solar technologies, either without storage systems or which can't reach such high temperatures."
Gemasolar can reach operating temperatures of over 500°C, much higher than plants with parabolic trough technology, as it does not require oil, but rather directly uses the salt as a transfer fluid. The salt, at over 500°C, generates hotter, pressurized steam to move the turbine, which significantly increases the plant's efficiency. Meanwhile, some of this hot salt is stored in order to continue generating electricity while there is no sunshine. Thus, Gemasolar, with a 19.9 MW turbine can supply electricity to a population of 25,000 inhabitants in the South of Spain.
Among the plant's most cutting-edge equipment is its receiver, located at the top of the tower over 130 m high, where the 2,650 heliostats of the solar field concentrate the solar irradiation at a ratio of 1000:1.