Battery energy storage system

A battery energy storage system is more than the battery cells themselves. In a home energy installation, BESS usually means the battery modules, inverter or battery inverter, BMS, controls, protection equipment and connection to the household electrical system. The system can charge from solar generation, from the grid or from both where the design allows it, then discharge stored electricity for household use or export. The term is useful because many documents use BESS to describe the installed storage system rather than a single battery product. A BESS does not automatically provide power during a grid outage unless it also has suitable isolation, backup circuits and manufacturer-supported backup operation.