Authors: Hachimenum Nyebuchi Amadi, Iyowuna Winston Gobo, Ugochi Benedicta Uche-Ibe, Richeal Chinaeche Ijeoma
Abstract: The reliance on fossil fuels and the need for effective battery management are significant challenges that renewable micro-grids seek to address. Fluctuations in supply and demand often result in higher operational costs and increased dependence on the external grid. With the urgent need to confront energy and environmental issues like global warming, transitioning to clean energy sources is becoming more viable. This study focuses on the Jetty 11kV feeder from the Abuloma 33kV injection substation in Port Harcourt, with an installed capacity of 1 x 7.5MVA. Currently, the feeder has a peak load of 3.9MW and an average load of 2.2 MW. To leverage the local abundance of water, the research aims to design a micro-grid using solar and wind energy. Using MATLAB Simulink, data from NASA meteorological sources will be simulated. The design features a 4.5MW photovoltaic (PV) array, a 2.5 MW wind energy source, and a 4 MWh battery storage unit. Despite variations in irradiance, significant improvements in power extraction were observed, with up to 4.5 MW generated by the PV array and 2.5MW by the wind turbine during peak times. The battery can be fully charged in four hours, and it was maintained at 40% capacity during low energy output periods. The State of Charge (SoC) of the battery showed dynamic behavior, enabling it to respond effectively to system imbalances and enhance microgrid resilience. A fuzzy logic controller (FLC) was used to manage charge and discharge cycles according to real-time parameters, ensuring reliable micro-grid operation even with low battery levels. The economic analysis revealed an initial cost of ₦990,251,352.19, a replacement cost of ₦414,669,375.12, a net present cost (NPC) of ₦10,813,540,000.00, and a levelized cost of electricity (COE) of ₦230.90/kWh. The low operation and maintenance (O&M) costs associated with renewable energy reduce reliance on the conventional grid and prolong infrastructure lifespan. Environmental assessments indicated a total greenhouse gas emission of 15,330,621 kg/year, significantly lower than that of conventional systems. The results confirm that the optimized hybrid renewable energy micro-grid enhances energy balance and resilience, showcasing its feasibility as a cost-effective and environmentally sustainable alternative to traditional power generation. The research aims to improve system resilience, reduce operating costs, and enhance micro-grid efficiency.
DOI: http://doi.org/10.5281/zenodo.17587580
