The Solar Tres Power Tower is the first commercial molten salt central receiver plant in the world and is currently under development in the district of Fuentes de Andalucia which is in the province of Seville in southern Spain. It will have the capacity to produce 17MW with the added capability of 15 hours storage which gives it an estimated operating time of 6500 hours / year.
A company, GEMASOLAR 2006 SA, has been created especially for the purpose of developing the Solar Tres project. This is a company that is 100% owned by SENER.
The project was developed jointly by SENER Group and CIEMAT when they reached an agreement in 2005 to develop a testing program for the SENER prototype panel.
The Solar Tres power plant will consist of a 298,000m2 solar field made up of 2,590 heliostats that will sit in concentric circles around a 130m tower. The solar heat will be directed at a receiver at the top of the tower. Molten salt is then pumped through the tower receiver which heats the liquid to around 600ºC. A portion of the fluid is then pumped to a heat transfer unit to create super-heated steam. The balance is pumped into a hot tank where it is stored for use in times when the sun is not shining. By using this storage method the electricity production can be more reliable and will ensure the power plant is producing power for longer periods throughout the day.
The super-heated steam runs a turbine/alternator group to generate electricity which is then fed into the power grid.
The 115m2 heliostats, developed by SENER, automatically track the sun so that the position of the reflective surfaces are accurately positioned to delevier solar energy to the receiver throughout the day. The key is to minimise the energy lost through overspilling.
The thermal power produced by Solar Tres is three times greater than that of previous models and it can withstand high intensities of solar radiation giving it a capability of operating at high levels of thermal efficiency.
It seems that every time further information about the project is released the vital details change. Whether it’s the number of heliostats, the size of the solar field or the height of the tower. So while development is continuing, don’t be surprised if the final size, capacity, heat levels have changed.
The technology used to create Solar Tres has been successfully tested as part of the Solar Two project that is currently in operation in the USA.
To read about other solar energy developments, visit the Solar Energy page.