Design and Modeling of a Stand-Alone Hybrid Energy System, in the Case of Kelto, Raya Chercher Tigray, Ethiopia

Abstract

Combining solar, wind, and diesel power offers a proven, reliable, and sustainable rural electrification solution for Ethiopia. Despite abundant renewable resources, Tigray suffers from severe electricity shortages and environmental degradation due to an unreliable grid and reliance on costly, polluting fuels. Transitioning to sustainable hybrid energy systems faces hurdles, including high upfront costs, technical expertise gaps, and complex policy frameworks. This study investigates the design of a stand-alone hybrid energy system for KELTO (ቁልጥቦ) village, Southern Tigray, Ethiopia, integrating solar photovoltaic (PV) generators, wind turbines, and a diesel generator as a backup. The research aims to establish a reliable electricity supply for 350 households, addressing the availability of renewable resources and reducing diesel consumption. Based on collected monthly energy demand data, a load profile was developed, revealing a daily electric demand of 165.44 kWh/d and a peak load of 20.46 kW. The optimized hybrid system achieved a renewable fraction of 65.6%, demonstrating a significant reliance on sustainable energy sources. Economic analysis yielded an internal rate of return (IRR) of 28% and a Levelized cost of energy (LCOE) of $0.3594/kWh, with a nominal discount rate of 8% and fuel price of $1.41/L. Comparing this optimized system to a base case system ($0.769/kWh), the study highlights the cost-effectiveness of the hybrid approach. The results indicate that hybrid systems offer a viable solution for rural electrification in Ethiopia, mitigating environmental impacts, reducing greenhouse gas emissions, and decreasing reliance on fossil fuel imports and potential of hybrid renewable energy technologies to provide sustainable and affordable electricity in off-grid communities.