Energy Storage Economics for Renewable-Powered Mini-Grids in North West Nigeria: A Comparative Analysis

Battery energy storage represents the largest single cost component and the primary technical limitation of solar-powered mini-grids in North West Nigeria, and optimising storage sizing, technology selection, and replacement scheduling is critical to achieving financial sustainability and service quality in off-grid electrification markets. This study conducts a comparative economic analysis of energy storage options for solar mini-grids in North West Nigeria, evaluating lead-acid, lithium iron phosphate, and second-life electric vehicle batteries across technical performance, total cost of ownership, and supply chain risk dimensions. Technical performance data were gathered from operational monitoring logs of 22 mini-grids in Kano, Jigawa, and Zamfara States provided by three mini-grid operators. Monte Carlo simulation was applied to model total cost of ownership variability under uncertain battery degradation rates, replacement cost trajectories, and operating temperature effects. Storage sizing optimisation was conducted for representative community load profiles using HOMER Pro. Results indicate that lithium iron phosphate batteries demonstrate 34 percent lower total cost of ownership over a ten-year project horizon compared to lead-acid alternatives, primarily through longer cycle life and reduced replacement frequency. Second-life electric vehicle batteries offer 18 percent further cost reduction but introduce supply chain and performance consistency risks that require mitigation through rigorous grading protocols. The study recommends a minimum performance certification standard for batteries used in Nigerian rural electrification projects. Keywords: energy storage, battery economics, mini-grids, North West Nigeria, lithium iron phosphate.