Roof-top solar panels keep homes cool in summer and warm in winter
A team of researchers at UC San Diego Jacobs School of Engineering carried out a study of the cooling benefits of rooftop solar modules using thermal imaging.
They found a building''s ceiling was up to 5 degrees Fahrenheit cooler under the array than under an exposed section of roof. At night, the panels help hold heat in, reducing heating costs in the winter.
"Talk about positive side-effects," said Kleissl.
His team determined that the amount saved on cooling the building amounted to getting a 5 percent discount on the solar panels' price, over the panels' lifetime.
The panels essentially act as roof shades, said Anthony Dominguez, the graduate student lead on the project.
Rather than the sun beating down onto the roof, which causes heat to be pushed through the roof and inside the ceiling of the building, photovoltaic panels take the solar beating and shade the roof.
In a test of a building on the UCSD campus, panels reduced the amount of heat reaching the roof by about 38 percent, the researchers said.
"There are more efficient ways to passively cool buildings, such as reflective roof membranes," Kleissl said.
"But, if you are considering installing solar photovoltaic, depending on your roof thermal properties, you can expect a large reduction in the amount of energy you use to cool your residence or business," he added.
The study will be published in the journal Solar Energy. (ANI -Posted on / )
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