Solar energy systems are an increasingly common sight on rooftops all across the U.S., but unless you climb up onto a roof, it can be difficult to figure out how big solar panels are and how much they weigh. This article will help you understand solar panel size, solar panel weight, and whether your roof can support solar panels.
How big are solar panels?
The average size of solar panels used in a rooftop solar installation is approximately 65 inches by 39 inches, or 5.4 feet by 3.25 feet. There is some variation from brand to brand, and if you’re installing a large-scale solar panel system (such as for a warehouse or a municipal building) your panels will be closer to 6 feet long.
Every solar panel is made up of individual solar photovoltaic (PV) cells. PV cells come in a standard size of 156 square millimeters, which is approximately 6 inches long and 6 inches wide. Most solar panels for rooftop solar installations are made up of 60 solar cells, while the standard for commercial solar installations is 72 cells (and can go up to 98 cells or more).
Solar panel size and weight, residential and commercial panels
|Residential Panels||Commercial Panels|
|# of Solar Cells||60||72|
|Average Length (inches)||65||78|
|Average Width (inches)||39||39|
|Average Depth (inches)||1.5 – 2||1.5 – 2|
The number of solar cells on one panel is directly related to its length. 72-cell commercial solar panels are approximately 13 inches longer than 60-cell residential panels.
If an average solar panel measures at 65 inches by 39 inches, how does that translate to a full-sized rooftop solar panel system?
The average system in the U.S. is 6 kilowatts (kW). If you install a 6 kilowatt (kW) system with 20 average-sized panels, your system will likely measure approximately 27 feet wide by 13 feet long – 352 square feet in all. (This assumes that your panels can be placed close together and that there are no obstructions on your roof.)
How much do solar panels weigh?
Understanding how much solar panels weigh is crucial if you’re planning on installing a rooftop solar system. Knowing a solar panel’s weight is the best way to be certain that your roof can support a full installation.
EnergySage reviewed product specifications for the top 10 solar panel brands most frequently offered to homeowners in the EnergySage Solar Marketplace and compared the weight of their standard 60-cell residential solar panels. While there is some variation from brand to brand, most panels weigh somewhere in the neighborhood of 40 pounds.
Of the top brands that we compared, the lightest was SunPower, with some panels weighing as little as 33 pounds. The heaviest was Canadian Solar, which has panels that weigh as much as 50 pounds.
|Solar Panel Manufacturers||Solar Panel Weight (60-Cell Residential Panels)|
|SolarWorld||40 – 47 lbs|
|Canadian Solar||40 – 51 lbs|
|Hyundai||38 – 41 lbs|
|Hanwha SolarOne||40 – 42 lbs|
|Hanwha Q CELLS||41 lbs|
|Trina||41 – 50 lbs|
|SunPower||33 – 41 lbs|
|Axitec||39 – 41 lbs|
|Kyocera||42 – 44 lbs|
Can your roof support a solar panel system?
Armed with the knowledge of solar panel size and solar panel weight, we can make a calculation about how much a whole solar panel system weighs – which in turn can help you understand whether your roof can support a new solar panel system or not.
In a 6 kilowatt solar installation made up of 20 solar panels, the panels alone will weigh approximately 800 pounds (20 panels x 40 lbs). Based on our calculation above, we know that this same system measures at 352 square feet, which works out to a weight of 2.3 pounds per square foot (800 pounds ÷ 352 sq ft). When you include the mounting hardware and other equipment for your panels, the total weight will be closer to 3-4 pounds per square foot.
The roofs on most newer homes can handle significantly more than 3 pounds per square foot of weight. However, if you have an older roof or are in any way concerned about whether your roof can support the additional weight of solar panels, talk to a roofing company. A straightforward roof inspection can help you determine whether the additional weight of solar panels are a viable option for your home.
Find the solar option that’s best for your home by comparing multiple quotes
Solar installers are used to customizing their system designs to meet the specific needs of each individual property. However, if you are considering installing solar panels on your roof, finding an installer that’s the right fit for your home may take a little shopping around. You can use the EnergySage Solar Marketplace to easily solicit and compare multiple offers from installers near you. If you have any questions or concerns about your roof, simply add a note in your profile when you register.