A Rural Security–Economic Stability Framework for Designing Hybrid Renewable Microgrids: A Representative Nigerian Case Study

Rural Nigerian communities face persistent electricity shortages, weak grid reach, diesel-price volatility, and limited productive-energy access. These conditions undermine household welfare, rural enterprise viability, health-service continuity, water supply, agro-processing, communication, and night-time security. Most hybrid renewable microgrid studies optimize levelized cost of energy (LCOE) or net present cost, while treating supply security, affordability under uncertainty, and socio-environmental performance as secondary outcomes. This paper develops a structured rural security–economic stability (RSES), framework for hybrid renewable microgrid planning. The framework contains five stages: resource profiling, load stratification, component sizing, multi-scenario optimization, and resilience stress-testing. A composite RSES index is introduced to combine reliability, autonomy, affordability, payback stability, renewable fraction, and avoided emissions into a single planner-facing score. The framework is applied to a synthetic but representative Northern Nigerian rural cluster of approximately 180 households and community services, with average demand of 410 kWh/day and peak demand of 68 kW. Four architectures are benchmarked: PV/Wind/Battery, PV/Diesel/Battery, PV/Wind/Hydrogen, and PV/Biomass/Battery. A reproducible custom hourly optimization model is used to simulate 8,760 hourly dispatch intervals. The PV/Biomass/Battery architecture achieved the strongest central performance, with LCOE of US$0.211/kWh, aggregate loss of power supply probability (LPSP) of 0.6%, renewable fraction of 94%, and RSES score of 0.80. The biomass result is reconciled through an explicit annual energy balance: the biomass generator supplies 23,900 kWh/year, consumes approximately 28.0 t/year of as-received residues, operates for 1,138 h/year, and uses only 4.8% of the assumed annual residue availability. The diesel-assisted design had competitive base-case cost but was most exposed to fuel-price shocks, while the hydrogen configuration achieved high reliability and renewable fraction but remained economically weak at the studied load scale. The results show that rural microgrid selection should be based not only on central LCOE but also on reliability, critical-load protection, payback stability, and shock-response bands.