Storing concentrated solar heat for dispatch
Thermal energy storage (TES) holds heat produced by concentrators for later use, enabling power generation or process heat on demand. TES integrates directly with CSP plants and improves dispatchability by decoupling solar collection from electricity production.
Common storage methods:
- Molten salt: a widely used medium because it stores heat at high temperature with good thermal capacity and moderate cost.
- Sensible heat in solids or fluids: rocks, concrete, or oils that store heat by temperature change.
- Latent heat storage: phase-change materials that store energy during melting and release it when solidifying.
Benefits and design points:
- Provides hours of full-load output after sunset or during clouds.
- Sizing depends on desired charge/discharge duration and thermal cycle.
- Integration requires heat exchangers, insulated tanks, and control systems to route heat between receiver, storage, and power block.
Properly implemented TES increases capacity factor, stabilizes grid integration, and makes solar concentration suitable for baseload or flexible peak generation.