Design and commissioning of a 2.5 MWh battery energy storage system

Momentary and sustained power interruptions are one of the most difficult and important power quality problems facing many industrial and commercial users. A particularly challenging problem is the need to supply an economical, dependable, efficient and controllable source of real and reactive power, which is available instantly to support a large (>1.0 MW) load, if the electric utility connection is lost. Battery energy storage systems (BESS) have the potential to provide versatile solutions to this problem for utility, industrial and commercial applications. This paper describes the design and installation a 5 MW peak, 2.5 MWh BESS which is now in commercial operation at the BNG Battery Recycling Facility in Vernon, California, USA. Results of commissioning tests are discussed. The BESS at Vernon provides the required power combined with both voltage and frequency control necessary to allow the Vernon facility to tolerate disconnection from the electric utility grid without suffering unacceptable impacts on critical loads.