VionX Energy and its partners will demonstrate a multi-hour, vanadium redox battery-based energy storage system (ESS) for load shifting, peak shaving, and renewable system integration. The 6-10 hour battery will not degrade as quickly as lithium ion and lead acid batteries, allowing a lifetime of 20 years. The ESS is a fully integrated system that comprises energy storage, power conditioning, system control, and thermal management subsystems. 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.