A grid-connected facility dedicated to storing surplus electricity and releasing it when demand or prices are high. While usually referring to massive lithium ion battery arrays, it can also apply to pumped hydro, compressed air, or flywheel installations. Dispatchers use these stations for frequency regulation, peak shaving, and smoothing out the variable output of renewable generation.
Dispatch wants the storage station to discharge at fifty megawatts for the next hour to help cover the evening peak.
Also heard as
- BESS
- battery energy storage system
Related terms
Peak shaving
The practice of reducing electrical power consumption during periods of maximum demand on the grid.
Time-of-use rates
A pricing structure where electricity costs vary based on the time of day and season.
Battery pack
A fully integrated enclosure containing multiple battery cells, wiring, and control electronics.