Design and Analysis of Grid-Connected Renewable Energy Based Microgrid Systems for Residential Use: A Techno-Economic Approach

Bangladesh faces a significant power shortage, prompting the need for renewable energy solutions in residential areas. This study analyzes the energy load of a three-story residential building and designs a grid-connected microgrid system incorporating solar PV and wind turbines using HOMER (Hybrid Optimization of Multiple Energy Resources) Pro software. Four configurations combining solar PV, wind turbines, and grid connections were evaluated based on techno-economic performance. The grid-connected solar PV system emerged as the optimal solution, offering the lowest net present cost (NPC) of USD 23,233, a cost of energy (COE) of USD 0.022/kWh, and an operating cost of USD 445 per year. The system generates 25,259 kWh/year, with grid purchases of 14,248 kWh/year and sales of 13,312 kWh/year, resulting in a renewable fraction (RF) of 62.2%. It demonstrates economic viability with a payback period of 6.69 years and a return on investment (ROI) of 10.1%. Additionally, the system significantly reduces CO2 emissions to 9,076 kg/year compared to 15,548 kg/year in the grid-only scenario. These results underscore the potential of grid-connected solar PV systems to enhance energy sustainability and decrease emissions in the residential sector of Bangladesh.