Cost-Effectiveness Diagnostics for Off-Grid Energy Systems in Rwandan Rural Communities: A Multilevel Regression Analysis

{ "background": "Access to reliable and affordable energy is a critical constraint for agricultural productivity and rural development in sub-Saharan Africa. While off-grid energy systems are increasingly deployed, robust methodological frameworks for evaluating their cost-effectiveness in real-world settings are lacking.", "purpose and objectives": "This study develops and applies a diagnostic framework to measure the cost-effectiveness of diverse off-grid energy systems supporting agricultural activities in rural communities. It aims to identify key technical, economic, and social determinants of cost-effectiveness.", "methodology": "A multilevel regression analysis was conducted on primary data from a sample of off-grid systems, including solar mini-grids and standalone solar installations. The core model is specified as: -Effectivenessij = \β0 + \β1Xij + \μj + \εij, where i denotes systems nested within communities j. Robust standard errors were used for inference.", "findings": "System capacity and the degree of community co-management were significant positive predictors of cost-effectiveness. Specifically, a 1 kW increase in capacity was associated with a 12.3% improvement in cost-effectiveness (95% CI: 8.1, 16.5). Diesel hybrid systems demonstrated significantly lower cost-effectiveness compared to purely solar systems.", "conclusion": "The multilevel diagnostic approach provides a nuanced assessment of cost-effectiveness, revealing that both technical scale and governance structures are critical for economic sustainability. Solely technical or financial evaluations are insufficient.", "recommendations": "Policymakers and project developers should prioritise capacity-building for community co-management structures alongside technical investments. Future energy access programmes should integrate diagnostic frameworks like the one presented for monitoring and evaluation.", "key words": "cost-effectiveness analysis, multilevel modelling, off-grid energy, rural electrification, agricultural development, Rwanda", "contribution statement": "This paper provides a novel diagnostic methodology combining technical and socio-economic variables within a multilevel regression framework, offering a