Optimization of a Photovoltaic Hybrid Energy Storage System Using Energy Storage Peak Shaving

Abstract

Electrical supply in rural areas, especially on small islands, commonly utilizes eco-unfriendly and costly diesel-based power plants. Renewable energy power plants can replace these diesel-based power plants. Thus, energy optimization is critical for the improvement of the energy efficiency of the renewable energy system. The optimization of a photovoltaic energy system through a hybrid energy storage system is analyzed for the off-grid island. The hybrid energy storage system involves the hybridization of two energy storage systems including a battery storage system and a hydrogen storage system. The management of a photovoltaic hybrid energy storage system requires a power management system. This paper proposes a power management system based on the peak shaving strategy in hydrogen energy storage to improve the efficiency of the hybrid energy storage system while considering the surplus energy forecasting. The hybrid energy storage system typically focuses on the efficiency of a closed system. In such a closed system, the optimization focuses on the life-saving of the battery. The energy storage peak shaving is used to improve the efficiency of the hybrid energy storage system, for the maximization of excess hydrogen to supply electricity to the islands. The result reveals that the average efficiency of the hybrid energy storage system based on the proposed power management system is 52.3%, which is 29.6% higher than the one obtained from traditional power management system strategy, whereas the battery depreciation is improved by 1.2%.