Optimization of an Autonomous Hybrid Renewable Energy System Using Reformed Electric System Cascade Analysis

This paper presents reformed electric system cascade analysis (RESCA) technique for optimization of hybrid renewable energy system (HRES) comprising of wind energy conversion system (WECS), photovoltaic (PV) system, battery energy storage system, and non-intermittent source (NIS). Optimization constraints of final excess energy, energy generation ratio, cost of energy, net present cost (NPC), and renewable energy fraction are considered for the optimization of the system. This optimization is realized for an isolated load comprising of the ten households in Malaysia with a daily consumption of 84.5 kWh. On successful implementation of RESCA with different constraints, it is found that the optimum size of energy sources for the HRES varies depending on the chosen constraints. Also, the NPC of the system can be considerably reduced on introduction of NIS to the HRES. RESCA provides the user with better insight into the influence of variation of PV and WECS power generation while identifying the optimal size of energy storage unit. The optimized results obtained are also compared with benchmark HOMER software to validate the methodology.