Techno-Economic Design and Sensitivity Analysis of a DC Microgrid for a Remote Community: A Case Study in Ghana

Abstract

Access to electricity is crucial to human development. Many villages in Ghana remain undeveloped due to a lack of electricity. One way to increase energy access is to electrify these communities using renewable resources. Resource availability, reliability, sustainability, and cost-benefit analysis are vital in the design process. To that end, this paper presents a techno-economic design of a renewable-energy-based microgrid for an island community in Ghana using HOMER Pro. To ensure an efficient design, factors such as maximum annual capacity shortage and minimum renewable fraction are utilized as design constraints. The proposed system combines a hybrid solar-wind-diesel generator-battery-converter as the optimal system architecture. From the simulation results, the optimal component sizes are solar-102 kW, wind-24.3 kW, diesel generator-30 kW, converter-50 kW, and battery-289 kWh. The system's total annual energy production is 207,827 kWh, with a 98.6% renewable fraction and an estimated yearly CO2 emission of 1,488 kg, making the system environmentally friendly. The reported capital, net present, and operating costs are $133,275.00, $250,689.00, and $4,696.54, respectively, at an LCOE of $0.09812. The system has a simple payback period of approximately 7 years with a 35.4% return on investment. Additionally, detailed sensitivity analyses are carried out on key variables, including fuel price, inflation, wind speed, solar radiation, and battery minimum state of charge to assess their impact on system performance. Finally, the study analyzes demand increases and load efficiency improvements to the existing system performance.