Investigating the thermal impacts of rooftop solar panels in hot humid climate: Bahrain

• Solar Panel (SP) showed higher thermal impact than MDF panel (MDFP) based on panels and roof surface temperature readings. • In winter, the solar panel’s BST rose by 9.55 °C at T1 (09:00), 11.30 °C at T2 (12:00), and 3.68 °C at T3 (15:00). • In summer, the solar panel’s BST exceeded MDF panel by 10.73 °C at T1, 12.38 °C at T2, and 4.22 °C at T3. • Roof Surface Temperature (RST) under the (SP) increased by 3 °C and 1.4 °C in summer, and by 1 °C and 0.7 °C in winter at T1–T2. • RST near the (SP) rose by 0.9 °C and 1.6 °C in summer, and by 0.6 °C and 3.5 °C in winter at T2 & T3. The thermal influence of the Rooftop Building-Integrated Solar Photovoltaic (RBISPV) has been investigated through experimental configurations employing a solar panel alongside a MDF wooden panel for data collection. The study investigated the Bottom Surface Temperature of the panels (BST), the Rooftop Surface Temperature (RST) located beneath both panels, and at a distance of 1 meter from both panels. Readings were taken at three specific intervals: between sunrise and noon (T1); at noon (T2); and between noon and sunset (T3), during the summer and winter seasons in Bahrain, and analyzed across both panels. The findings indicate that in the summer season, the BST of the solar panel consistently surpassed that of the MDF wooden panel, exhibiting temperature differentials of 10.73 °C at (T1), 12.38 °C at (T2), and 4.22 °C at (T3). In the winter season, the solar panel exhibited heightened BST readings, reflecting differences of 9.55 °C at T1, 11.30 °C at T2, and 3.68 °C at T3. In contrast, the measurements of RST beneath the solar panel exhibited an increase of 3 °C and 1.4 °C during the summer, and an elevation of 1 °C and 0.7 °C in the winter, corresponding to (T1) and (T2), respectively. At (T3), the RST beneath the MDF wooden panel showed increases of 0.5 °C and 0.1 °C relative to the area beneath the solar panel in summer and winter, respectively. Measurements taken at a distance of 1 meter from the panels indicated that the temperatures adjacent to the solar panel rose by 0.9 °C and 1.6 °C in summer, and by 0.6 °C and 3.5 °C in winter, during (T2) and (T3), respectively. During (T1), the temperature adjacent to the MDF wooden panel recorded at a higher value of 2.1 °C in contrast to that near the solar panel. The results reveal a significant accumulation of heat from the RBISPV. Moreover, it emphasizes methods to reduce heat buildup on solar panels, as this thermal phenomenon contributes to the Urban Heat Island (UHI) effect, resulting in various negative environmental consequences, such as changes in weather patterns and global warming.