One square kilometre of desert is sufficient to supply about 100 000 households with 250 million kilowatt-hours of electricity per year. Solar-thermal power plants, which use the concentrated rays of the sun to generate electricity, can make a big contribution to future energy generation. According to current studies, more than 15% of European electricity requirements could be produced from concentrating solar power systems in 2050.
The German Aerospace Center (DLR) and Endesa test direct solar steam generation and energy storage in this pilot plant in Carboneras, located in southern Spain. In this type of solar power plant, steam is produced directly from concentrated solar radiation and used to drive a generator. The highlight of this facility is a new system that efficiently stores energy, both as sensible and latent heat. The stored energy can be used to generate electricity even at night.
DLR (CC-BY 3.0).
The salt-based latent heat storage system works using a phase transition. At 305 degrees Celsius, the salt absorbs energy by transitioning from a solid to a liquid state. Latent heat is 'hidden' energy. Energy is accumulated as the storage medium changes phase from solid to liquid.