The Impact of State of Charge Management When Providing Regulation Power With Energy Storage

Recent work suggests that further integration of wind and solar resources into the power grid will increase the demand for regulation and load following. The purpose of this letter is to investigate an important aspect of using energy storages for providing regulation: The short-term energy restoration of such limited energy resources (LERs) coincides with load following operations and could therefore lead to higher load following requirements. We therefore analyze the impact of corresponding scheduling approaches on load following energy and capacity using stochastic simulations. In particular, we compare the load following impact of a basic control strategy proposed by the stakeholders of the Independent System Operator in California (CAISO) to a strategy that attempts to manage the energy level of LERs such that their impact on load following requirements is optimal. Our results show that such smart state of charge management could even reduce the demand for load following while satisfying the full regulation demand in the CAISO control region.