Central receiver plants collect the solar energy concentrated by the heliostat field in a central receiver mounted at the top of the tower. There have been several alternative heat transfer fluids which have been successfully tested until now: saturated steam, superheated steam, molten salt and pressurized atmospheric air.
The first commercial central receiver plant was commissioned in June 2007 in Spain (11 MW) and two other ones are now operating (50MW in total). The typical size for a tower plant so far varies between 10 to 150 MW.
Concentrates solar radiation on a point receiver at the top of a tower
Enables operation at high temperature level (550ºC over heated steam and 565ºC for molten salts; working with pressurized air at temperatures of up to 1000ºC are under study) and provides heat storage capabilities
Has high net solar to electrical efficiency and is a commercially proven technology
Size: 10 to 150 MW
Demo plants built in the 80's
Three commercial plants in operation in Spain (11 ,20 MW and 17 MW with 15h of storage) and 1 more under construction (17 MW + 15h storage)
Solar energy to electric power performance: Design point 20%. Annual 17%.
Larger projects under construction in the USA.
Prices of PPA that will make projects feasible: between 14 and 18 c€/kWh depending on the level of solar radiation, size of the plant, capacity factor, financial conditions, etc.