Optimal Scheduling of an Integrated Photovoltaic - Battery Storage System Considering Energy Capacity Fade and Revamping Strategy

This paper proposes a revenue-maximization model for an Integrated Photovoltaic - Battery Energy Storage System, where the storage unit is connected behind the meter of the generator. The proposed approach returns an optimal solution that accounts for the capacity degradation pursuant to cyclic actions of the battery. Note that embedding the capacity degradation into an optimization problem is not straightforward due to its intrinsic non-linear feature. Nonetheless, neglecting this phenomenon may expose the battery to significant revamping costs. This is rather concerning when operating systems over a multiyear planning horizon since significant effects of capacity degradation are evident only over long-time intervals. A Mixed Integer Linear Programming is presented where the main features of the capacity degradation are accurately integrated by means of ad-hoc reformulation techniques. Furthermore, the model co-optimizes the operation of both the photovoltaic generator and the battery while providing the optimal revamping strategy to replace the degraded cells and boost the energy capacity. Case studies indicate the effectiveness of the proposed model also when different technical parameters of the battery are adopted.