Solar panels are a 25-year investment, and the brand on them matters more than most homeowners realize. You could look for a list of “bad” brands, but those lists go out of date quickly because manufacturers merge, rebrand or go under. It’s more useful to know the warning signs. Here are six red flags that should make you think twice about any panel brand.
No Tier 1 Bankability Rating
BloombergNEF gives Tier 1 status to manufacturers that are financially stable enough for banks to fund large projects built with their panels. The rating doesn’t measure quality, but it’s a strong sign the company will still be around when you need it. If your installer can’t tell you whether their panel brand is Tier 1, ask why.
A Warranty From a Company That’s Gone
A 25-year warranty is only worth something if the company behind it survives. Solyndra collapsed in 2011 and SunEdison went bankrupt in 2016, and many of their customers were left with warranties nobody would honor. Choose manufacturers with a long track record, a U.S. presence, and warranty coverage that is insured by a third party.
Weak Product and Performance Warranties
Good panels today usually come with a 25-year product warranty. They also guarantee about 85–90% of their original output after 25 years. Be wary of a brand that offers only 10–12 years of product coverage or promises less than 80% output by year 25. That tells you how much the manufacturer trusts its own hardware.
Missing Certifications
Any panel installed on a U.S. home should be listed under UL 61730 (or the older UL 1703) and certified to IEC 61215. These standards test fire safety, weather resistance and long-term durability. If a panel isn’t certified, don’t buy it.
Poor Performance in Low Light and Heat
Here in the Pacific Northwest, cloudy days are a fact of life. On the spec sheet, check the temperature coefficient: closer to zero is better, and around -0.30%/°C is a good target. Also ask how the panel performs in diffuse light. Cheap panels often look fine on paper in full sun but produce less power the rest of the year.
Unknown Brands at Rock-Bottom Prices
If one quote is far below the others, find out exactly which panel it includes. Off-brand panels sold online or by high-pressure door-to-door sellers often have no verifiable test data and no U.S. support. You may also have no practical way to file a warranty claim.
The Bottom Line on Brands
The best way to avoid a bad solar brand is to work with an installer who’s open about what they install and why. Before you sign anything, ask for the spec sheet, the warranty documents and the manufacturer’s Tier 1 status.
Ready to compare your options? The Solora Solar team will walk you through the panels we install, the warranties behind them and what makes sense for your roof, with no pressure. Request your free quote today.