Solar Panel Warranties Explained: What's Actually Covered

Solar contracts bundle together three genuinely different warranties, and confusing them is one of the most common ways homeowners misunderstand their coverage.

1. Product (equipment) warranty

Covers manufacturing defects in the physical panel — typically 10-25 years depending on the manufacturer, with premium brands generally offering longer terms. This is the panel maker's warranty, not the installer's, so it survives even if your installer goes out of business.

2. Performance (power output) warranty

Guarantees the panel will still produce at least a specified percentage of its original rated output after a given number of years — commonly something like 90% after 10 years and 82-87% after 25 years. If your panels degrade faster than the guaranteed curve, the manufacturer owes you a remedy (repair, replacement, or partial refund, per the specific contract terms).

3. Workmanship (installation) warranty

Covers the installer's labor — roof penetrations, wiring, mounting — separate from the equipment itself. This is usually the shortest warranty (5-10 years) and the one most directly tied to your specific installer's reputation, since it's only as good as the company's ability to honor it years later. It's worth weighting installer longevity and reviews more heavily than usual if this warranty period matters to you.

Inverter warranties are separate again

Inverters typically carry their own 10-25 year warranty, shorter than panels in many cases (string inverters especially), since they're the component most likely to need replacement within your system's lifespan.

What to ask before signing

• Are all three warranties (product, performance, workmanship) in writing, with specific years and coverage terms — not just verbal assurances?
• What happens to the workmanship warranty if the installer goes out of business? (Some manufacturers offer a backstop program for this.)
• Is the warranty transferable to a new homeowner if you sell?