According to the study by Kleissl and his team, the direct economic return (energy saved) and indirect (sale of excess energy) is the main advantage of installing a photovoltaic system, but not the only one. In fact, solar panels also guarantee a fair percentage of thermal insulation in both summer and winter.
He is about to end up run over, his mother saves him
The title is not the latest advertising slogan of a company solar panels, but the result of research conducted by Jan Kleissl, professor of environmental engineering atUC Jacobs School of Engineering di San Diego. According to the study by Kleissl and his team, the direct economic return (saved energy) and indirect (sale of excess energy) is indeed the main advantage of installing a photovoltaic system, but not the only one. In fact, solar panels also guarantee a fair percentage of thermal insulation in both summer and winter.
Specifically, a room under a roof covered with solar panels can have a temperature of up to 5 degrees Fahrenheit inferior compared to the same room under a panelless roof. The reason is obvious: on the one hand, each single module is able to retain a good amount of heat, on the other hand the cavity that is usually created between the roof and the panels themselves, creates an air tunnel that avoids overheating of the building, and, consequently, of the internal rooms. All this results in a cut on the cost of the air conditioner of about 5%.
Not only that: identical savings can also be obtained in winter, since - again according to Kleiss & co. - the solar panels would be able to gradually release the accumulated heat, provided, of course, that there was a minimum of irradiation during the day. A little like what happens in old country houses, where the external walls act as thermal insulation in both good and bad seasons.
The team is now busy fine-tuning a software able to process various variables (exposed surface, exposure time, average irradiation, etc.) to return the exact calculation of the savings in bill. Certainly a nice discovery… even for solar panel manufacturers!
Roberto Zambon
