According to a study by Jan Kleissl for an upcoming issue of Solar Energy, solar panels just don’t provide clean energy but also cool buildings, workplaces and homes by nearly 5°F than under an exposed roof. A professor of environmental engineering at the UC San Diego Jacobs School of Engineering, Jan Kleissl led his team of researchers to this discovery during their study of the cooling advantages of photovoltaic panels. While solar panels provide power and cool buildings in the day, they hold the heat in at night, lowering heating costs during winters.

These days consumers are depending more on solar energy to power their houses and offices. So its necessary to evaluate the exact positive impact of solar panels on the energy costs, Kleissl said. He research discovered that the amount saved on cooling the building equaled five percent discount on the solar panel’s price over a lifetime.

In April, the solar panel roofs of Powell Structural Systems Laboratory, fitted with a thermal infrared camera were used for study to collect the data. The building is installed with tilted solar panels at some places while some portions are not covered by panels.

According to Anthony Dominguez, one of the leads of the projects, the solar panels act as shades reflecting the sun’s heat rather the pushing them inside the roof and heating the building. Much of the heat is removed by the blowing wind between the panels and the roof. It is the beneficial if the panels are tilted as the open gaps will let the air circulate between the solar panel and building.

Although the study was spread over only over a period of three days, Kleissl is confident that it will allow them to predict cooling effects throughout the year. In areas like San Diego the contrast theory of panels cooling the building in summer and heating them up in winter essentially cancels each other out.

The study was financed by NASA Graduate Student Research Program, National Science Foundation, California Public Utilities Commission, the Department of Energy and the California Energy Commission.