Design and Techno-Economic Evaluation of a Hybrid Mini-grid System for an Academic Institution

Abstract

Inadequate electricity supply is a global challenge that needs solutions. This situation has compelled the purchasing of fossil fuel-generating units for use in residential, commercial, and industrial sectors to generate electricity. However, using fossil fuel generating units cause greenhouse gas emissions, bringing about environmental pollution and ultimately resulting in climate change. In particular, educational institutions require adequate and reliable power supply to ensure proper learning and teaching, which is lacking in developing countries like Nigeria. Fortunately, Nigeria has enormous renewable energy sources such as solar energy, which can be utilized through photovoltaic (PV) modules to generate clean energy fed into a mini-grid. This novel approach focused on an educational institution that will enable adequate electricity from the mini-grid for proper learning and teaching, reduced negative environmental impacts, and lower energy costs. Therefore, this research is focused on developing an effective hybrid utility grid-diesel generator-solar PV mini-grid system for the Faculty of Engineering and Technology of the Nigerian Defence Academy, Kaduna. Design analysis and techno-economic evaluation of the mini-grid were carried out using the HOMER Pro software tool, which was also used to simulate and optimize the mini-grid. The results revealed that the hybrid system comprising the grid, diesel generator, PV, and converter was technically and economically viable. The net present cost (NPC) of $182,065.20, producing a total energy of 836,430 kWh/year, was obtained and gave 0.00198 $/kWh as a levelized cost of energy (LCOE). Correspondingly, a renewable fraction (RF) of 98.3% was attained, thus meeting the Faculty's daily load demand of 575.64 kWh/day, thereby providing a reliable and improved energy supply at the best cost. Therefore, a hybrid system such as this one is proposed for tertiary institutions to ensure greater electric power supply availability.