Solar thermal electricity generating systems with thermal storage

摘要

Thermal energy can be stored in a fluid-based thermal storage system for later use. The stored thermal energy may be derived from steam generated using insolation in a steam-based solar power system. The thermal storage system can store energy when insolation is generally available. Alternatively or additionally, the thermal energy may be derived from electricity from the electrical grid. For example, the thermal energy can store energy when the electrical grid has excess electricity available for storage. At a later time, the energy stored in the thermal storage system can be released to heat pressurized water or steam in addition to or in place of steam generated by the insolation. For example, the stored thermal energy may be used in preheating the solar power system during startup, in supplementing steam output of the solar power system, or to replace steam generation during low insolation periods.

主权项

1. A method of producing electricity comprising:
during a first time period:
generating steam in a solar receiver in a solar thermal system using insolation directed onto the solar receiver;producing electricity by driving a steam turbine using the generated steam from the solar receiver; andat a same time as said generating steam and the producing electricity, storing heat energy in a thermal storage fluid, which includes a molten salt and/or a molten metal, by at least one of heating the thermal storage fluid using an electric heater and heating the thermal storage fluid by burning a fossil fuel; and during a second time period:
producing electricity by transferring the heat energy stored in the thermal storage fluid to the solar thermal system; wherein the heat energy stored during the first time period is sufficient to generate steam for use by the steam turbine in the producing electricity during the second time period.