Premium Power and its partners will demonstrate a multi-hour, zinc bromide battery- based energy storage system (ESS) for load shifting, peak shaving, and renewable system integration. The project is based on Premium Power’s modular 500 kW, multi-hour energy storage system, providing capacity on demand. The ESS is a fully integrated system that comprises energy storage, power conditioning, system control, and thermal management subsystems. National Grid will be demonstrating this technology. Two ESSs are to be demonstrated with National Grid at locations in Massachusetts. One ESS will be integrated into a single 500kW multi-hour system installed next to a 605 kW photovoltaic (PV) array in Everett, MA and the other ESS will be interfaced with a 600 kW wind turbine at the Holy Name High School feeder in Worcester, MA. National Grid will deploy, operate, and monitor the aggregated 1MW ESS’s in their respective locations for two years.