An optimal operating strategy for combined RES–based Generators and Electric Storage Systems for load shifting applications

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.