Hybrid Renewable Microgrid Optimization for Cost Reduction, Emission Mitigation, and Net-Metering Grid-Connected Stability in University Student Residences for Developing Countries

• Optimized hybrid PV/Wind/Biomass/BESS microgrid reduces NPC by 35.3% and COE by 69.5%. • Achieves 85% renewable fraction with 69.6% CO₂ emission reduction. • Net-metering reduces grid purchases by 66% while increasing annual energy sales. • MATLAB simulations confirm voltage and frequency stability within Bangladesh Grid Code. • Provides a replicable model for sustainable student housing in developing countries. The increasing energy demand of institutional facilities, coupled with rising electricity costs and emission concerns, necessitates the development of efficient and sustainable hybrid renewable energy systems. Although numerous studies have investigated hybrid microgrids, limited attention has been given to campus-scale systems that integrate multiple renewable sources with grid-connected net-metering and practical operational considerations. This study aims to design and optimize a grid-connected hybrid renewable microgrid for a university student residence using real load data. The proposed system integrates photovoltaic, wind, biomass-based generation, battery energy storage, and utility grid support, and is analyzed using HOMER Pro to evaluate techno-economic performance, renewable penetration, and emission reduction. The optimized configuration achieves a daily energy demand of 390.56 kWh with a peak load of 53.4 kW, resulting in a significantly reduced net present cost and cost of energy, along with substantial reductions in greenhouse gas emissions compared to the base case. Sensitivity and comparative analyses further demonstrate the robustness of the proposed system under varying resource and economic conditions. The findings confirm that multi-source hybrid microgrids with net-metering can provide a cost-effective and environmentally sustainable energy solution for campus-scale applications.