Design of a Solar-Biogas-Diesel Hybrid System for Sustainable Agro-Dairy Electrification in Rural Bangladesh

Abstract

This study addresses the critical energy challenges faced by rural agro-dairy farms in Bangladesh, where unreliable grid access, high operational costs of diesel generators, and environmental degradation hinder productivity and sustainability. This study will provide an optimal off-grid hybrid energy system (HES) based on solar photovoltaic (PV), biogas generated by cattle waste and diesel back up to provide reliability, economic and eco-friendly energy supply. Through the HOMER Pro software, the design of the system emphasizes technical feasibility, economic feasibility, and carbon difference and is in accordance with the sustainability agenda in the world.The HES set up consists of the following 5.88 kW solar PV array, 3 kW biogas generator, 2-kW diesel backup, and battery to fulfill energy consumption demand of 30.3 kWh per day. The results of simulation show dominance of the renewable energy, where solar and biogas totaled 96.6 percent of the annual power generation, or 11,407 kWh, to leave the diesel at only 3.48 percent. The system also has 100 percent energy reliability where unqualified demand has been eliminated. Economically, it yields a competitive Levelized Cost of Energy (LCOE) of $0.177/kWh and a Net Present Cost (NPC) of $28,804, with a 15.4-year payback period. Environmentally, the HES reduces CO2 emissions by 35.8% (321 kg/year) compared to diesel-only systems, while biogas valorization mitigates methane emissions through efficient cattle waste management. This research establishes a scalable model for decentralized energy systems in agrarian economies, emphasizing policy interventions such as subsidized financing, regulatory reforms, and technical training to accelerate adoption. By harmonizing renewable energy integration with socio-economic development, the study advances sustainable agriculture, energy security, and climate resilience in off-grid communities.