Assessment of solar energy potential and climatic effects on utility-scale photovoltaic power generation in The Gambia

The aim of the present study is to investigate the technical and economic viability of implementing photovoltaic (PV) systems in The Gambia by analyzing the availability of the solar resource, system performance, generation capacity, and economic viability. Long-term climate data from the NASA POWER database have been used to evaluate global horizontal irradiation, ambient temperature, rainfall, relative humidity, cloud cover, and wind speed at five locations in The Gambia. The analysis shows good potential for solar energy use, with annual GHI values ranging from 5.776 to 5.886 kWh/m²/day. Seasonal analysis revealed higher electricity generation during the dry season due to lower cloud cover, rainfall, and humidity. For 100% PV penetration, annual electricity generation ranges from 886.13 GWh in Soma to 913.87 GWh in Banjul. Correlation analysis shows that cloud cover (r = −0.976) and precipitation (r = −0.944) have the greatest negative impact on PV electricity production. System losses were also found to range from 21.34% to 22.80%, mainly due to variations in temperature and radiation. Moreover, the economic analyses indicated that the cost of electricity of proposed systems is within the range of 50.77-52.94 USD/MWh with a payback period of less than six years. This demonstrates the economic viability of utility-scale photovoltaic solar energy systems. The results show that the use of large-scale photovoltaic solar power systems can help provide a cost-effective alternative to fossil fuel-based electricity production by government institutions in The Gambia.