An optimal operating strategy for combined RES-based generators and electric storage systems for load shifting applications

Abstract

This paper focuses on an optimal operating strategy of combined RES-based generators and electric storage systems for small/medium-scale public facilities. The operating strategy can be used in load shifting applications in response to a time-of-use (TOU) rate design with differential pricing for on- and off-peak usage. Load shifting applications can be exploited by customers using battery energy storage systems (BESS) in order to reduce their electricity bill, charging the storage when off-peak time periods are applied and discharging it during on-peak periods, when electricity energy prices are high. The operating strategy is implemented within a bidirectional converter that provides an interface between the low voltage (LV) grid and a PV generator combined with a BESS, so as to contemporary addressing the requirements of the national reference technical standards for active users connections and providing different ancillary services.