Improving Electricity Supply Reliability: A Case Study of Remote Communities of Limpopo in South Africa

Energy is playing a more fundamental function in human growth and advancement. Many rural households in developing nations, like South Africa, are still lacking access to basic electricity due to being located far away from the national grid and grid expansion to these areas is quite expensive. Fewer rural communities are electrified through the use of diesel and grid systems of which are having a high operating and maintenance cost and are the biggest carbon emissions producers. The deployment of renewable energy sources (RES) based microgrid systems are considered as a more viable approach to supply power to rural communities in the world. RE-based microgrid systems have the greatest potential to meet load demand, improve quality of life and create job opportunities, and provide electricity access for rural communities of SA. In this study, a case study is utilized to design and simulate a suitable grid-tied hybrid microgrid system architecture for rural communities’ conditions. The study selected three isolated rural communities (Tjiane, Phosiri, and Malekapane villages) of Ga-Mphahlele in Limpopo province (SA) as case studies, and these communities have similar weather conditions because they are located in close proximity. The unreliable national grid system is the main source of power in these communities while diesel generators (DG) are used as backup system during load shedding. In this study, HOMER software was used to design a grid-tied hybrid microgrid power system of which will help with eradicating system power failure and load shedding from the national grid. Based on the simulation, optimization, and sensitivity analyses results show that the optimal grid-tied microgrid system architecture was proposed based on lower net present cost (NPC), lower cost of energy (COE), a maximum renewable fraction (RF), loss of power supply probability (LPSP), and the optimal system should produce fewer carbon emissions. The achieved results for all examined rural communities show that the optimum microgrid system architecture consists of a grid, solar PV, wind turbine (WT), DG, battery, and power converter is more capable of satisfying customer electricity demand in a dependable approach and provide good power quality. The results showed that Grid/PV/WT/DG/Battery/Converter is a winning hybrid microgrid system architecture that is more cost-effective and environmentally friendly with NPC of R2.973793; COE of R0.02842 and an RF of 97.8% with total emissions of 58.626 kg/yr for Tjiane, NPC of R1.836202; COE of R0.03092 and an RF of 97.9% with a total emission of 32,888 kg/yr for Phosiri, and NPC of R1.209773; COE of R0.02370 and an RF of 97.9% with total emissions of 28.002 kg/yr for Malekapane. The proposed Grid/PV/WT/DG/Battery/Converter microgrid is considered the most favorable grid-connected hybrid microgrid system architecture which is a more suitable and relaible electricity supply solution for rural communities. The results showed that sensitivity variables, financial parameters, wind speed, solar irradiations, and diesel price differences have a substantial influence on the optimal design of grid-connected hybrid power systems for rural electrification.