A Battery Energy Storage Sizing Method for Parking Lot Equipped With EV Chargers

Parking lots (PLs) equipped with electric vehicle (EV) chargers will be the most convenient places for EV users to charge their cars. However, there is a high degree of unpredictability around how car parks are used, especially shopping centre parking lots (SCPLs). Moreover, the cluster charging of EVs in PLs may destabilise the grid. The application of a battery energy storage system (BESS) in PLs is a potential way to reduce the impact of EV charging on the grid. This article proposes an approach for estimating the size of a stationary BESS for PLs in a constrained grid. At first, the intermittent charging demand of EVs is determined by considering the travel patterns, charging needs, and driver behavior of EVs. Then, a region reduction method combined with nonlinear optimization is proposed to estimate the optimal size of the BESS such that the capital cost and operational cost of the SCPL are minimized. The proposed sizing method 1) ensures the maximum utilization of the stationary BESS, 2) avoids over/under-sizing, 3) reduces operational costs, 4) and maintains the reliability of the system. The applicability of the proposed method is shown by simulating different cases, characterized by real household travel survey data and shopping centre car park occupancy data.