Optimization of a Hybrid Solar–Wind–Biogas–Battery Energy System with Phase Change Material for Off-Grid Power Supply

The fluctuating output of renewable energy sources such as solar and wind creates challenges in supplying continuous and dependable electricity, especially in remote and off-grid areas. To overcome this limitation, hybrid renewable energy systems integrating solar photovoltaic (PV) panels, wind turbines, battery storage, and biogas-based power generation were investigated. In this study, phase change material (PCM) was incorporated with PV modules to reduce panel temperature and improve energy performance. Four hybrid system configurations, namely PV–Wind–Battery, PV–PCM–Wind–Battery, PV–Wind–Biogas–Battery, and PV–PCM–Wind–Biogas–Battery, were evaluated under hot and humid climatic conditions representative of Chennai, India. The systems were optimized with the objectives of minimizing the net present cost (NPC) and cost of energy (COE). For the PV–Wind–Biogas–Battery configuration, PCM integration resulted in an NPC saving of approximately USD 0.22 million and reduced the COE from USD 0.099/kWh to USD 0.094/kWh, corresponding to an approximately 5.1% reduction. Similarly, for the PV–Wind–Battery configuration, PCM integration resulted in an NPC saving of approximately USD 0.17 million and reduced the COE from USD 0.120/kWh to USD 0.105/kWh, representing a 12.5% reduction. These results demonstrate that PCM integration can improve the techno-economic performance of hybrid renewable energy systems. The PV–PCM–Wind–Biogas–Battery configuration shows considerable potential for reliable, economical, and sustainable off-grid electricity supply under the hot and humid climatic conditions of Chennai, India.