Photovoltaic panels can reduce roof temperatures

High temperatures can significantly affect the performance of photovoltaic (PV) panels by reducing their efficiency and power output. This paper explores the consequential effect of various rooftop coverings on the thermal performance of photovoltaic (PV) panels.

Indirect benefits of rooftop photovoltaic (PV) systems for building insulation are quantified through measurements and modeling. Measurements of the thermal conditions throughout a roof profile on a building partially covered by solar photovoltaic (PV) panels were conducted in San Diego, California.

The results revealed that covering the roof beneath the installed PV panels reduces their temperature and increases efficiency. The best performance was observed when placing wet wooden flakes beneath the panels, with an efficiency increase of 5%. Moreover, the woolen insulation offered an efficiency rise of 12% near sunset.

Photo: Adobe Stock. A simulation shows city-wide installation of photovoltaic solar panels on roofs could raise temperatures during the daytime and lower them at nighttime. Widespread coverage of building rooftops with conventional photovoltaic solar panels may increase temperatures on hot days and lower them at night, says new modelling.

Here we show that, in Kolkata, city-wide installation of these rooftop photovoltaic solar panels could raise daytime temperatures by up to 1.5 °C and potentially lower nighttime temperatures by up to 0.6 °C.

At night, PV panels induced a slight cooling effect compared to the bare roof, reducing temperatures by up to −2.72 °C hourly and −0.46 °C on a monthly average basis. Conversely, during the daytime, both PV and PVIGR sites exhibited localized warming above the panels, with temperature increases reaching up to 4 °C at noon on sunny days.