Optimal sizing of battery energy storage in a microgrid considering capacity degradation and replacement year

Nowadays, microgrids (MGs) have received significant attention. In a cost-effective MG, battery energy storage (BES) plays an important role. One of the most important challenges in the MGs is the optimal sizing of the BES that can lead to the MG better performance, more flexible, effective, and efficient than traditional power systems. This paper proposes a novel set of formulations to determine the optimal BES size, technology, depth of discharge (DOD), and replacement year considering its technical characteristics, service life, and capacity degradation to minimize the MG scheduling total cost and improve the precision and economic feasibility of the BES sizing method. Moreover, the modeling of BES considering capacity degradation is presented. The proposed model of the planning problem is formulated using mixed-integer linear programming (MILP) to ensure the convergence of the optimization problem. The effectiveness of the proposed approach is confirmed by numerical simulation based on historical data of a real MG.