Power load analysis and configuration optimization of a hybrid microgrid integrating food waste-to-biogas and photovoltaics

The growing challenges of urban food waste accumulation and the urgent demand for low-carbon energy transition highlight the need for integrated solutions that couple waste management with renewable energy utilization. However, most existing studies have not fully achieved an effective integration of high-efficiency energy utilization and resource circularity, leading to limited energy recovery and weak system synergy. To address these issues, this study proposes a novel microgrid system that couples PV power generation with food waste treatment to achieve efficient energy utilization and resource valorization. The system incorporates anaerobic digestion for biogas production, biogas power generation, waste heat recovery, and the use of residual heat for insect protein production. A comprehensive system framework is created, with subsequent optimization of parameters and refinement of the energy dispatch strategy to improve performance. The proposed system achieves multi-stage energy cascade utilization, maximizing waste-derived energy recovery and reducing energy losses compared with conventional microgrids. The optimized LCOE for the grid-connected mode is 0.075 $/kWh, representing a 17.58 % reduction compared to the isolated mode. Optimization results reveal that the grid-connected mode achieves LOLP of 5.91 %, CO₂ emissions of 163 t/year and insect protein production of 7.17 t/year, whereas the isolated mode yields an LOLP of 0.42 %, CO₂ emissions of 45 t/year, and insect protein production of 10.56 t/year. Compared with recent studies on PV–biogas-based microgrids, the proposed system achieves a significantly lower LCOE , demonstrating strong techno-economic advantages and providing a scalable pathway for the development of high-efficiency microgrids aligned with circular economy principles.