Investigation of annual performance of a building shaded by rooftop PV panels in different climate zones of India

Photovoltaics panels are generally used on rooftop for electricity generation. However, installation of PV on the rooftop also has potential impact on the heating and cooling load of the building. This work studied these indirect benefits of rooftop PV panels by conducting experiments in Raipur, India, and compared the results with the exposed roof. Further, mathematical model is presented to analyze the annual effect of PV shading in terms of thermal load saving and power generation. Annual variation of cooling/heating load, PV power generation and overall energy-saving efficiency index is presented for different climatic zones of India. Average annual reduction in the roof and ceiling temperatures for different cities are in the range 6.05–10.96 °C and 3.94–7.15 °C, respectively. Annual cooling load reduced by 70.33–94.37%. Although PV panels shading shows negative impact during the winter season by increasing the heating load of building in all the climatic zones, the overall thermal load of building may reduce up to 22.76–74.07%. Furthermore, the overall energy-saving efficiency index varies from 21.27 to 25.12%, with maximum efficiency observed for Jodhpur city followed by Raipur. Overall, this study highlights the potential of rooftop PV application in buildings under different climatic zones of India.