Techno-Economic and CO2 Emissions Reduction Analysis of Solar Rooftop Microgrid System using HOMER

Solar rooftop microgrid systems offer an effective solution to meet growing energy demands while reducing greenhouse gas emissions. However, adoption is often limited by high initial costs, performance uncertainty, and solar variability. In countries with high solar potential like Malaysia, grid-connected and hybrid photovoltaic (PV) systems present a viable path toward cleaner and more resilient energy infrastructure. This study evaluates the techno-economic feasibility and environmental impact of two configurations: a solar PV-only (SPV) system and a diesel-solar photovoltaic (D-SPV) system, using Hybrid Optimization of Multiple Energy Resources (HOMER) software with real data from Universiti Teknologi MARA (UiTM), Permatang Pauh. Results show that the SPV system achieved a lower Cost of Energy (COE) of RM 0.1606/kWh and Net Present Cost (NPC) of RM 281,709.90, with only 105 kg of CO2 emissions annually. The D-SPV system recorded higher costs (COE = RM 0.5105/kWh; NPC = RM 895,415.00) and produced 114,740 kg CO2 per year. The SPV system proves more economical and sustainable for urban areas with stable grids, while the D-SPV setup offers reliability for off-grid regions. Overall, adopting grid-connected solar microgrids can cut carbon emissions by over 99.9% and reduce lifetime energy costs by 68%.