Optimal design of a photovoltaic–diesel–battery hybrid renewable energy system for sustainable off-grid electrification of a village in Ethiopia

Rural electrification in developing regions remains a major challenge due to the absence of grid infrastructure and high costs of energy distribution. This study presents the design, simulation, and optimization of a hybrid photovoltaic (PV)–diesel–battery system to supply reliable electricity to an off-grid village in the Jawi region of Ethiopia. With an annual load demand of 153,396.36 kWh and average solar radiation of 1211.8 kWh/m2/year, a hybrid configuration comprising an 81 kW PV array, 25 kW diesel generator, 45 kW converter, and 200 batteries was modeled using PVsyst and HOMER software. Various system configurations were evaluated based on net present cost (NPC), cost of energy (COE), fuel consumption, and CO₂ emissions. The optimized hybrid system achieved a net present cost of 7,284,233 Birr, a cost of energy of 4.468 Birr/kWh, annual diesel consumption of 9,377 L, and CO₂ emissions of 24,693 kg, with a renewable contribution of 84%. Compared to the diesel-only configuration, the hybrid system significantly reduced both fuel usage and emissions while improving reliability and long-term sustainability. Sensitivity analyses confirmed system robustness against variations in fuel price and PV cost. The results demonstrate that a PV–diesel–battery hybrid system offers a technically feasible, economically viable, and environmentally sustainable solution for off-grid electrification in rural Ethiopia.