Should You Buy Used Solar Panels?
If a convenient transaction is the most important aspect of purchasing solar panels, the homeowner should definitely stay away from used versions. Shopping for used solar panels can take considerably more due diligence than shopping for new panels. However, there are a few key principles that can help you disqualify a bad deal–and with used solar panels, anything less than a great deal is a bad deal. Here are some tips that can help you separate the good from the bad.
The first principle to keep in mind is that it’s essential to buy from local vendors. Online marketplaces are tempting, and recommended for many other types of used products, but solar panels have a few characteristics that need to be examined in person. You want to able to test the output for yourself, especially since most online used solar energy vendors make a point of selling as-is. You definitely don’t want to pay for shipping costs only to find out that you’ve purchased a lemon.
Related to in-person examination is testing the output of the panel yourself. You should always carry a multimeter with you when looking at solar electricity products of any kind. Since you only need to test the voltage and amperage, you don’t need a fancy multimeter; a $20 model is more than sufficient. Your goal is to see if the panel’s output is anywhere in the ballpark of it’s stated rating. Solar panel manufacturers expect the performance to degrade over time, and typically designate a 30-year life expectancy to most panels.
Don’t be surprised if the panel under examination only provides 60% to 75% of it’s original rating. While that might seem disappointing, the goal is usually not buy one panel (which is usually not enough, regardless of whether it’s new or used), but for all the panels you run together to add up to the output required for your house’s energy needs. In this context, “good enough” is relative to the price. You’ll still get all the advantages of solar power with an inefficient panel, within reason. For instance, if you can get a panel rated at 100 watts that actually outputs 50 watts for $75, your paying $1.50 a watt, which is a better deal than most new solar energy panels.
Finally, avoid buying panels that you can’t examine in person. Those online marketplaces that empower buyers to comparison shop aggressively are of no use if you have to buy pay high shipping costs before finding out that panel you bought has some defect that wasn’t brought to your attention head of time. Some of these defects look worse than they actually are. If the panel has browned over time, the performance won’t be affected. If the wiring is loose, you can solder it back into shape if you know how, or you can mend it with a silver-infused epoxy like CircuitWorks Conductive Epoxy. Crack glass or condensation trapped underneath can be fixed by replacing the glass. Keep in mind that if you see loose wiring or condensation, the conductivity will be lowered, or the continuity of the circuit may be broken–so a multimeter test will be inaccurate. Only buy solar panels with these defects if you’re willing to make the necessary repairs and can insist on a very low price.