Heat storage — storing solar energy directly as thermal mass rather than converting it to electricity and back — is 5 to 10 times cheaper per kWh of storage capacity than battery storage, lasts indefinitely, and requires no electronics, BMS, or inverter. The trade-off: you can only use the stored. This gigantic solar thermal energy storage tank holds enough stored sunlight to generate 1,100 MWh/day from stored solar power. This enables CSP systems to be flexible, or dispatchable, options for providing clean, renewable. To store heat for days, weeks, or months, you need to trap the energy in the bonds of a molecule that can later release heat on demand. Thermal storage options include sensible, latent.