How is Energy Stored?

The principle behind any energy storage method is the same - to store energy at off-peak hours in order to be able to utilize it during full load intervals.

Thermal energy (TES) can be stored long-term and also for shorter durations, depending on the application type. TES is suitable for both small and large-scale facilities, from operating buildings to powering up towns.

The following components make up a TES setup:
- Chiller
- Building cooling coils
- Diffusers
- Storage tank

Thermal energy is produced during low peak hours and is collected in the thermal energy storage tank. During high-peak intervals, the water is withdrawn to be distributed to the facility. Diffusers, which are located at the bottom of the tank, aid in the passage of warm and chilled water as it enters and exits the tank. Diffusers also eliminate turbulence in the water flow.

Storage methods for electrical energy vary, depending on factors such as the amount of energy needed to be stored, storage duration and how quickly energy required is released. METCO supports rechargeable batteries as a viable form of EES. Batteries like Sodium Sulfur (NaS), lithium ion, and flow batteries can be used for large-scale rechargeable EES. These batteries are useful for both power quality, and load leveling by providing electricity during peak demand. There are 950 MW of U.S Department of Energy verified commercial battery projects in operation installed worldwide.