Which statement about energy storage in renewable systems is true?

• A. Concentrated solar power (CSP) with thermal storage is a common approach to smooth energy output.
• B. Storage is unnecessary because renewable energy is infinite.
• C. All renewables have identical storage needs.
• D. Storage cannot improve reliability.

Answer: (A)

Energy storage helps renewable systems deliver electricity reliably by time-shifting generation to match demand. In concentrated solar power, mirrors focus sunlight to heat a fluid, often molten salt, which is stored in insulated tanks. That stored heat can later be used to produce steam and drive a turbine, even when the sun isn’t shining. This ability to store energy smooths out the natural variability of solar output and makes the power from CSP more dispatchable, helping to keep the grid balanced.

The other statements overlook this reality: renewables aren’t infinite in a given moment, so there are times when generation falls short unless there’s storage or backup; different renewable technologies have different storage needs and capabilities; and storage can and does improve reliability by supplying power during gaps.