How Many Solar Panels Can I Fit On My Roof?
To calculate the number of solar panels you can fit on your roof, you need to divide the available square footage of your roof by 15. For example, if you have 450 square feet of
To calculate how many panels can fit on your roof, divide your open roof space by 20 square feet (or however large your particular solar panels are). For example, if you have 500 square feet of open, available roof space, that's enough space for about 25 solar panels.
850 square feet of usable roof space for solar: The average U.S. roof is about 1,700 square feet. You should never put panels on northern roof planes. So with a north/south roof, that gives you 850 square feet. 400-watt solar panels that are 20 square feet in size: This is the most frequently quoted panel power output on EnergySage.
Assuming all of the roof space you've got is usable for solar (which, again, usually isn't the case), that's 42 panels (850 square feet divided by 20 square feet per panel). Multiplying the number of panels by the 400-watt power output of each panel gets us a system size of about 16.8 kW.
Our solar panel calculator helps you determine how many solar panels can be installed on your roof and how much electricity they can generate. It calculates the maximum number of panels that fit on the available roof surface, taking into account important factors such as orientation, inclination, and panel type.
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