2017-02-10 10:52:56 -0500
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Solar panels are made up of individual silicon solar cells which are a standard size of approximately 6" x 6". Most panels come with 60 cells, but some have an additional row of cells, which make them slightly larger. A 72 cell solar panel would have a higher power output rating than a 60 cell solar panel made of the same materials, because it has more solar cells on it.
If you're looking at a home solar installation, you probably don't need a 72 cell panel. 60 cell panels are more common for residential rooftop solar installations, while 72 cell panels are more common for ground-mounted, commercial, or utility sized solar installations.