Microgrid for the mitigation of load shedding in South Africa commercial buildings

Load shedding in South Africa has severely hindered governance and the operation of critical urban infrastructures, such as government complexes, leading to frequent interruptions in public service delivery. While solar photovoltaic (PV) microgrids are recognised as a viable alternative to grid dependency, most existing research focuses on rural or residential applications, leaving a gap for site-specific assessments of urban office buildings that prioritize service continuity during grid instability. This study investigates the design and optimisation of a hybrid microgrid, integrating solar PV, battery storage, diesel backup, and a grid connection, to meet the power requirements of a government office complex in Johannesburg. Using Hybrid Optimisation Model for Electric Renewables (HOMER) Pro software and recorded hourly consumption data, the system was modelled by employing a load-following dispatch strategy alongside simultaneous multi-objective optimisation for cost and environmental impact. The study reported PV-Battery-Grid (PV-B-GR) configuration as the optimal solution. This configuration yielded a Levelized Cost of Energy (LCOE) of ZAR1.11 and a Net Present Cost (NPC) of ZAR1, 842,856. While its operating costs are slightly higher than configurations with heavier generator use, it provides the lowest emissions of pollutants such as CO₂, CO, SO₂, and NOx. This study provides a framework for achieving energy independence in commercial buildings, while offering a scalable roadmap for policymakers to mitigate the impact of the South African energy crisis and replicate it for other climes.