The Influence of Tilt and Orientation on Photovoltaic System Voltage Output in Auchi, Edo North, Nigeria.

Abstract

This study examines how tilt angle and cardinal orientation (North, South, East, and West) affect the voltage output of solar panels throughout the day in Auchi, Edo North, Nigeria. The experimental setup consisted of an iron stand measuring 1.2 m in height, supporting four 20 W solar panels, each connected to a 75 Ah battery through an individual 12 V charge controller. Voltage readings were taken simultaneously from the four panels at a single tilt angle per day, ranging from 1° to 30° in increments of 5°, at 30-minute intervals between 17 July and 16 August 2023.The results show that tilt angle and orientation play a significant role in performance. At lower tilt angles (0°–9°), all orientations delivered closely matched and stable voltage values during peak hours (09:00–16:00). Increasing the tilt angle to around 10° improved voltage production during early morning and late afternoon, thereby widening the effective generation period and boosting total daily energy output. The south-facing panel at 10° recorded the highest peak voltage (22.9 V), exceeding its nominal open-circuit voltage and indicating local irradiance above the standard 1000 W/m² [10] or [13] (irradiance–voltage behavior). A modest decline in peak voltage was noted at tilt angles after 10 degree tilt. Overall, despite all panels following the typical daily voltage profile-rising after sunrise, reaching maximum output around midday, and falling toward sunset, the analysis highlights that optimal energy capture depends on an appropriate combination of tilt angle, orientation, and local irradiance conditions. These findings offer valuable guidance for PV system design in similarly hot and sunny environments.