Experimental Investigation of Solar Photovoltaic Tilt Angles for Maximum Energy Harvest in Kogi State, Nigeria

This study aimed to investigate the impact of tilt angles on solar radiation, current, voltage, and power output of a photovoltaic system, while also employing mathematical modeling to predict solar radiation. This study experimentally investigates the effect of tilt angle (0°, 7.8°, 22.8°, 37.8°, and 52.8°) on the performance of 10W polycrystalline solar panels in Kogi State, Nigeria, over a 12-month period (November 2023–October 2024). Solar radiation, current, and power output were measured at 20-minute intervals using data loggers, voltmeters, and ammeters. The study only investigates the effect of tilt angle and does not consider other factors that may impact solar panel efficiency, such as dust accumulation, temperature, or shading. Results show that optimal performance varies seasonally: lower angles (0°–7.8°) yielded higher radiation and power during peak dry seasons (e.g., November, 613.67 W/m² at 22.8°), while steeper angles (22.8°–37.8°) performed better in transitional months. The 7.8° tilt achieved the highest yearly average radiation, whereas the 0° tilt produced the highest average current (0.300 A) and power (4.51 W). These findings suggest that adjusting tilt angles seasonally can maximize solar energy efficiency in Kogi State, with 7.8° recommended as the best annual fixed tilt.