The common dimensions for residential solar panels are 65 inches by 39 inches, and commercial panels are typically 77 inches by 39 inches for grid-tied systems, which connect to an existing power grid. Off-grid panels vary in size. SunPower panels are 61 inches by 41 inches for residential installations as of 2014.
Solar panels range from 1.4 to 1.8 inches deep, and 1.8-inch depths are increasingly common. The standard residential panel has 60 solar cells, which convert light into electricity, and SunPower panels have 96 cells. Standard industrial solar panels have 72 cells.
Solar panels in residential installations typically weigh approximately 40 pounds. Depending on the roof’s weight-bearing capability and frame, installers may need to reinforce the roof’s structure before installing solar panels on a home. Commercial panels typically weight around 50 pounds.
Under standard test conditions, most solar panels generate from 230 to 275 direct current watts of electricity, and SunPower panels generate 327 to 345 direct current watts. In conditions that more closely reflect natural environmental conditions, standard panels generate 10 to 15 percent less electricity than in test environments. Standard home appliances run on alternating current electricity, so home and business owners must install an inverter to convert the direct current from the panels into usable electricity.