Geospatial Multi-Criteria Optimization of Wind-Solar-Biomass-Hydro Synergies for Resilient Off-Grid Electrification in Ethiopia

Abstract

Despite significant progress in Ethiopia’s national grid expansion, approximately 50% of the population remains off-grid. Traditional electrification strategies, primarily reliant on centralized hydropower and extensive grid extensions, face prohibitive capital expenditures (CAPEX) for "last-mile" connectivity in the diverse Ethiopian highlands. While standalone solar PV is the current default off-grid solution, it suffers from a critical "Reliability Gap" during the rainy season (Kiremt) and requires massive investment in battery storage to meet nighttime demand. This study utilized the Energy Access Explorer (EAE) to develop a geospatial framework for identifying hybrid renewable energy hubs. By applying strict exclusion zones—including a 10 km buffer from existing transmission lines and a 2.5 km buffer from distribution lines—to prevent investment overlap with national utility plans, we filtered for high-potential off-grid zones. Suitability was determined based on population densities of 100–600 people/km2 and rigorous technical resource thresholds (e.g., Solar GHI >2000 kWh/m2 /year, Wind Speed >4.5 m/s). The analysis identified approximately 138,280 km2 of land suitable for off-grid development, impacting 23.6 million people. The study’s primary contribution is the quantification of overlapping resource synergies: · Represents the most significant opportunity, covering nearly 110,000 km2 and impacting over 17.6 million people. This combination is a "High Strategic Priority" as dispatchable biomass compensates for solar intermittency. · Solar and Wind: Covers 67,700 km2 and impacts 10.8 million people, offering technical advantages through alternating generation peaks that reduce battery storage requirements. · "Energy oasis" (All 4 Resources): A highly reliable hub covering 12,040 km2, where quadruple redundancy ensures near-100% stability for critical infrastructure like healthcare and schools. · For widespread, cost-effective electrification, policy should prioritize Solar-Biomass hybrid systems to maximize demographic return on investment. Furthermore, the identified Solar-Wind corridors should be targeted for mini-grid development to leverage their natural diurnal complementarity, with an estimated competitive Cost of Energy (COE) of 0.162/kWh.