Optimization dispatching strategy for an energy storage system considering its unused capacity sharing

In renewable energy systems, energy storage systems can reduce the power fluctuation of renewable energy sources and compensate for the prediction deviation. However, if the renewable energy prediction deviation is small, the energy storage system may work in an underutilized state. To efficiently utilize a renewable-energy-sided energy storage system (RES), this study proposed an optimization dispatching strategy for an energy storage system considering its unused capacity sharing. First, this study proposed an unused capacity-sharing strategy for the RES to fully utilize the storage’s unused capacity and elevate the storage’s service efficiency. Second, RES was divided into “deviation-compensating energy storage (DES)” and “sharing energy storage (SES)” to clarify the function of RES in the operation process. Third, this study established an optimized dispatching model to achieve the lowest system operating cost wherein the unused capacity- sharing strategy could be integrated. Finally, a case study was investigated, and the results indicated that the proposed model and algorithm effectively improved the utilization of renewable-energy-side energy storage systems, thereby reducing the total operation cost and pressure on peak shaving.