bess
Round-Trip Efficiency
Also known as: RTE
Ratio of energy out to energy in for a complete charge-discharge cycle of a BESS, typically 85–92% for LFP systems.
Round-Trip Efficiency (RTE) is the ratio of energy delivered to the grid during discharge to energy taken from the grid during charge, for a complete cycle. Losses come from BMS overhead, inverter inefficiency, cell internal resistance, and thermal management. Modern LFP BESS systems typically achieve 85–92% RTE.