All in one 3 Phase outdoor battery and inverter cabinet - 50kW/107kWh The RI-ENERGYSET-3P-ESS-50-107 is part of Rayleigh Instruments growing family of renewable energy products. Individual pricing for large scale projects and wholesale demands is available. This EG outdoor Battery Energy Storage System (BESS) features a 100KW Power Conversion System (PCS) and a 215KWH LiFePo4 battery system. The PCS provides a 400V three-phase. This is a working principle diagram of a solar energy storage system, showing the process from solar power generation to energy storage, use and grid connection.