RELIABILITY

The chronic unreliability of Nigeria's national power grid necessitates a dependency on costly and environmentally damaging diesel generators, particularly for critical institutions like universities. The literature validates Hybrid enewable Energy Systems (HRES), specifically the Photovoltaic (PV)-Diesel-Battery configuration, as a technically superior and sustainable alternative for offgrid power. However, a granular, site-specific reliability assessment for the unique and energyintensive load profile of a Nigerian engineering faculty represents a significant gap in existing research. This study addresses this gap by providing a bespoke techno-economic analysis and reliability evaluation for a standalone hybrid power system for the Faculty of Engineering at the niversity of Benin.This research adopts a simulation-based methodology centered on the Hybrid Optimization Model for Multiple Energy Resources (HOMER) Pro software. The analysis is founded on a comprehensive on-site electrical load survey, which determined the faculty's detailed operational patterns and an annual energy demand of 737,686 kWh. This granular, real-world load profile, along with local solar irradiance and ambient temperature data for Benin City, was used to model, simulate, and optimize thousands of system configurations. The primary objective of the optimization was to identify the component sizing (PV array, battery bank, and diesel generator) that meets the faculty's load with the highest reliability at the lowest possible life-cycle cost.The simulation results identified an optimal system configuration consisting of a 525 kW PV array, a 198 kWh Battery Energy Storage System (BESS), and an 85kW diesel generator relegated to a backup role. This system achieves 100% reliability with zero unmet load, a 100% renewable energy fraction, and a highly competitive Levelized Cost of Energy (LCOE) of ₦0.0548/kWh. The analysis confirms that this configuration completely displaces the need for diesel fuel, thereby eliminating significant operational costs and preventing approximately 553 tonnes of CO2 emissions annually. The findings conclusively demonstrate that a properly sized PV-Battery hybrid system is a technically reliable, economically superior, and environmentally sustainable solution to the faculty's energy challenges.

The rising cost of grid electricity and the global push for sustainable energy solutions have heightened interest in renewable-based power systems. This project presents a comprehensive reliability assessment and techno-economic analysis of an islanded (standalone) Solar Photovoltaic (PV) and Battery Energy Storage System (BESS) designed to meet the entire electrical load of the Department of Electrical and Electronics Engineering at the University of Benin. The study utilized HOMER Pro software to model, simulate, and optimize the system. A detailed load profile of the department was developed and used as the primary input, alongside solar irradiation data for the Benin City location. The system was designed to operate without any grid connection, making reliability the paramount design constraint. The optimization process aimed to find the most cost-effective system configuration that minimizes the Net Present Cost (NPC) while adhering to a strict maximum allowable capacity shortage of 1%. Using HOMER Pro software, an optimal system configuration was determined: a 180 kW solar PV array coupled with a 100 kWh Lead-acid battery bank. The system demonstrates high reliability, meeting 98.98% of the annual load demand while maintaining complete energy independence. Economic analysis shows the system achieves a Levelized Cost of Energy of ₦619.5/kWh, proving it to be a technically feasible and financially viable sustainable energy solution for the department. The study confirms that islanded PV-Battery systems can provide reliable power while offering long-term economic benefits compared to conventional alternati