Two great questions many peopleask about solar panels are: “Which panels have the highest efficiency?”and, “Which solar PV panels are the best?”
This solar power panelcomparison chart compares the output per square foot surface area ofmost 200 W model solar panels. All of the modules on this chart arelabel rated at 200 Watts, which means in strict laboratory conditions,they produce the same output. However, I have compared them based ontheir PTC ratings which is the rating given under realistic testconditions. Sanyo, SunPower, Schuco, Kyocera, Suntech, GE, Evergreen,Canadian Solar, and Sharp are common solar panel manufacturers used byinstallers in the US.
Of the highest output panels, both Sanyo and SunPower panels have the highest efficiency per surface areain real world conditions. Given a limited roof area with which toinstall solar panels, these panels are the best choice to produce themost electric output per square foot. However, this doesn’t mean thatthese panels will always be the best choice.
The chart below shows 30 of the most common and efficient solarpower panels on the market and listed on the State of California’s “List of Eligible SB1 Guidelines Compliant Photovoltaic Modules”as of July 1, 2009. The PTC/Sqft is basically how many watts per squarefoot that panel will produce. (click on image to enlarge)
So, if I know the most efficient solar panels, then I know whichsolar panels are the best, right? Well, if efficiency is all you careabout, then yes. But efficiency may not be the most important factor.I would argue that the two most important factors in choosingthe best solar panels are 1) the annual kWh production (the expectedoutput) and 2) the price.
Would you pay more for “more efficient” panels,if I told you I could get you a less expensive system that outputsmore, fits on your property and lasts just as long?
Check out my solar panel comparison chart for a more in depth explanation.