Thermal energy storage for advanced solar central receiver power systems

Thermal energy storage is used in the advanced solar central receiver power systems currently being studied under Department of Energy sponsorship. This report describes: (1) the storage operating requirements imposed by interface constraints between energy storage and the receiver and electrical power generation systems, (2) several storage concept candidates which may meet these requirements, (3) potential cost differences between each of the storage concepts, and (4) the technical uncertainties associated with each storage concept. The storage concept candidates include (1) all sodium sensible heat with hot and cold storage tanks; (2) sodium/cast iron sensible heat using thermocline principle; (3) air/rock sensible heat using thermocline principle; (4) air/MgO sensible heat using thermocline principle; (5) air/cast iron sensible heat using thermocline principle; (6) molten salt sensible heat using thermocline principle; (7) molten salt sensible heat with hot and cold storage tanks; and (8) molten salt/rock sensible heat using thermocline principle.