University of California San Diego: Solar Cools As Well As Heats

Let's hear it for the home team: the University of California San Diego conducted a study that says rooftop solar panel arrays keep buildings cooler than buildings without solar panels. Most folks choose to have photovoltaic cells installed on their houses and business because they know it as a source of heat and san diego solar energy, however, they might not be aware that it could help cool the building as well.

In April, the UC San Diego Jacobs School of Engineering conducted a study led by professor Jan Kleissl that showed that rooftop solar panels can passively cool a building effectively. The study was performed with the use of thermal imaging cameras to take pictures of the solar array on top of the Powell Structural Systems Laboratory, which is part of the Jacobs School of Engineering. The results of their study revealed that the parts of the roof under the solar panels remained consistently 5 degrees Fahrenheit cooler throughout the day than the parts of the roof exposed to san diego solar rays. The panels provide a shade from the sun and the majority of the sun's rays are absorbed by the solar panels. Not all panel arrays created equal cooling effects though; the Powell Laboratory building has both a flat array and a tilted array, and the thermal camera demonstrated the roof space under the tilted array to be cooler than the flat one.

UC San Diego's study results could prove to be very valuable to consumers. Professor Kleissl and team did the math from their study and came up with the amount of heat hitting the roof was reduced by 38% and the amount saved on cooling costs would equal getting a 5% discount on the cost of the solar panels. Buildings in windier areas could see an even higher percentage of savings because of the increased cooling effect of wind blowing between the panels and the roof. "There are more efficient ways to passively cool buildings, such as reflective membranes," said Kleissl. "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."