Considering Battery Degradation in Energy Storage System Design for Multi-Services Scenarios

Abstract

In order to optimally size battery energy storage systems (BESS), it is necessary to take into consideration the degradation of the battery. Battery degradation in grid applications depends on the services provided by the energy storage and its operational regimes. In this paper, we propose a bi-level multi-objective optimization model to optimize the design of a BESS that simultaneously provides peak shaving and frequency regulation services. In the lower-level optimization, the daily scheduling scheme of the BESS is optimized to maximize the daily profit of the BESS. In the upper-level optimization, the rated capacity and power of the BESS is optimized to maximize the return on investment (ROI) of the BESS for the life cycle. The equivalent number of cycles of the BESS is calculated by using a rainflow algorithm to estimate the equivalent value loss of BESS in each day. In addition, the calendar aging and cycle aging of battery capacity and power capability is evaluated for every year. The simulation results using realistic data show that considering battery degradation in the optimization model reduces the battery number of cycles by about one half with a reduction in revenue, while still being profitable.