Solar News

Researchers from the University of California, San Diego (UCSD) have recently released a study which explores the effects that roof-mounted solar panels may have on the thermal heat storage capacity of the building ceiling they are attached to. During the summer, the research team found that solar panels cool the buildings on which they are installed. Using thermal imaging techniques, UCSD researchers found that solar panels act as giant sun shades and that building ceilings directly under panels were 5°F cooler that comparable top-floor building ceilings without panels.

Reuters reports that tilted solar panels reduce heat better than flush panels by allowing for passage of air underneath, which further cools the building ceilings. In the winter, research showed that panels had insulating effects; although they keep some sunlight heat out during the day, they hold in heat at night and allow the building to recoup the energy loss then. The study concludes that solar modules reduce the amount of heat reaching the roof by as much as 38 percent. Energy savings on home cooling systems as a result of this panel cooling effect amounted to getting a 5 percent discount on the price of the panels themselves.

"Using solar panels to passively cool buildings is not the most efficient method", research director Jan Kleissl said to the IB Times UK, 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."

A consistent thought among those pondering whether or not to go solar is, "What will my return on the investment (ROI) be?" At SolarTown, we realize that going solar is not only a large monetary investment, but also a lifestyle investment. It takes careful consideration of many factors to make the leap into solar energy, but ROI is likely to be a significant factor. ROI weighs benefits of going solar, including costs avoided, against the costs of solar PV installation. The UCSD study posits that solar shading will offset energy costs spent on air conditioning, and therefore increase your ROI. So if you are on the fence about installing solar on your home, remember that the panels may inadvertently save you money on your air conditioning bill.

An article from Green Building Pro argues that "cool roofs and solar panels are a natural marriage of sustainable technologies." More research will show just how applicable this study is to all rooftops with solar PV installations. If the shading effect is corroborated in future studies, we may start to see panels that are optimized to give the most shade benefits.