Quick answer
Most home solar systems carry four warranties: a panel product warranty (often 12–25 years), a panel performance warranty (typically 25–30 years, guaranteeing most of the original output), an inverter warranty (about 10–25 years depending on type), and the installer's workmanship warranty, which varies the most. The workmanship warranty covers leaks and installation errors, so get it in writing.
What warranties come with a solar system?
| Warranty | Who backs it | Typical length | What it covers |
|---|---|---|---|
| Panel product | Panel manufacturer | 12–25 years | Defects in the panel itself |
| Panel performance | Panel manufacturer | 25–30 years | A minimum share of rated output, often around 80–90% by the end |
| Inverter | Inverter manufacturer | About 10–12 years for string inverters (often extendable); up to 25 for microinverters | Inverter failure |
| Battery | Battery manufacturer | Often about 10 years, sometimes with an energy-throughput limit | Capacity and failure |
| Workmanship | Your installer | Varies widely, from a few years to 25 | Installation errors, roof leaks at mounts, wiring |
Which solar warranty matters most?
The workmanship warranty. Equipment failures are uncommon and backed by large manufacturers, but leaks, loose wiring and failed connections trace back to the installation. It's also the warranty that disappears if the installer goes out of business, so the company's track record matters as much as the number of years.
Ask whether the workmanship warranty includes removing and reinstalling panels for roof repairs, and whether it covers labor as well as parts.
How do Illinois Shines rules protect me?
Projects in Illinois Shines must use an approved vendor and give you the program's standard disclosure form before you sign, which lists the system's equipment, cost, warranties and financing. The program's contract requirements also set rules for any performance guarantee a seller offers. Keep the signed disclosure form with your warranty documents. See how to spot solar scams in Illinois.
What should I check about warranties before signing?
- 1
Get every warranty in writing
Panel, inverter, battery and workmanship, with lengths and who to call.
- 2
Ask about labor
Manufacturer warranties sometimes cover the part but not the labor to swap it.
- 3
Check transferability
Make sure warranties transfer to a buyer if you sell. See selling a home with solar.
- 4
Register the equipment
Some manufacturers require registration to activate the full warranty term.
Sources
This guide is general information, not tax, legal or financial advice. Incentive programs change, so confirm current terms with your installer, your utility and a tax professional.