Optimal sizing of substation-scale energy storage station considering seasonal variations in wind energy

Abstract

This study investigates an optimal sizing strategy for substation-scale energy storage station (ESS) that is installed at substations of transmission grids to provide services of both wind power fluctuation smoothing and power supply for peak load simultaneously. The proposed strategy first involves an optimal charging and discharging scheme enabling ESS to offer both services, considering particularly seasonal output variations of surrounding wind farms connected at the substation. Consequently, an optimisation model of ESS capacity is formulated to achieve trade-off between various costs and benefits involved in offering services by ESS. Case studies based on historical wind power data are conducted to validate the performance of the proposed method, and the simulation results demonstrate that this method can significantly reduce the ESS size and achieve promising benefits from power supply for peak load.