Assessment of Monthly Variations in Global Solar Radiation Over Abuja, Nigeria

This study assesses the global solar radiation of Abuja, located in north-central Nigeria, using maximum and minimum temperature data for the period of January to December 2024. The Hargreaves–Samani model was employed to estimate the monthly global solar radiation. Results revealed that global solar radiation was generally higher during the dry season (January–March and October–December) and lower during the rainy season (May–September). The study further indicated that global solar radiation varies with the maximum temperature, regardless of the season. It was observed that the global solar radiation in Abuja fluctuates almost every month, implying that the amount of energy expected from solar energy systems in the area also varies monthly. The lowest radiation value was recorded in August (14.99 kWh). These findings are valuable to solar power users, as they highlight the need to manage energy consumption during periods of low radiation and to consider backup power options during the rainy season. Additionally, the results will assist solar energy designers, installers, and policymakers in proper planning, system sizing, and component selection. Given that this research utilized average monthly data for only one year, it was recommended that future studies incorporate data spanning two or more years to achieve more reliable and comprehensive assessments of global solar radiation in the study area.