How long do solar panels last?
Solar panels last 25 to 30 years or more. They do not stop working — they slowly lose output, typically about 0.5% a year, so a panel still produces roughly 85–88% of its original power at year 25. The inverter is what usually fails first, around year 12–15.
What degradation actually looks like
| Year | Output remaining | Notes |
|---|---|---|
| 1 | ~98% | Small initial drop in the first months, then it settles |
| 10 | ~93% | Usually still comfortably inside warranty |
| 25 | ~86% | End of typical performance warranty |
| 30+ | ~83% | Still generating; many 1990s arrays are still running |
Two warranties, and they are not the same
- Product warranty — covers manufacturing defects and physical failure. Typically 12–25 years.
- Performance warranty — guarantees output stays above a stated curve, usually ~85–87% at year 25.
A long performance warranty is worth little if the product warranty is short, and both are worth nothing if the manufacturer folds. Prefer established manufacturers over headline warranty numbers.
The inverter is the real consumable
What actually kills panels early
- Bad installation — the single most common cause. Poor flashing leaks; poor wiring corrodes.
- Hail — panels are tested to withstand roughly 25mm hail at 80 km/h. Severe storms exceed that.
- Micro-cracks from walking on panels or careless handling during install.
- Delamination from moisture ingress, usually a manufacturing defect that appears within a decade.
What this means for the maths
Our estimates model 25 years because that is the warranted life. In practice most arrays keep producing well past it, so a system that pays back in 9 years plausibly delivers 20+ years of near-free electricity. How payback works →
What this looks like in real cities
Measured rooftop data, spanning the range from fastest to slowest payback we have found:
| City | Sun hrs/yr | Rate | Payback |
|---|---|---|---|
| Honolulu, HI | 1,787 | 42.1¢ | 3.1 yrs |
| Washington, DC | 1,562 | 17.4¢ | 8.8 yrs |
| Indianapolis, IN | 1,451 | 15.3¢ | 10.6 yrs |
| Lexington, KY | 1,496 | 12.2¢ | 13.2 yrs |
| Gatineau, QC | 1,291 | 7.9¢ | 33.3 yrs |
Frequently asked
Do solar panels stop working after 25 years?
No. 25 years is the typical performance warranty, not a lifespan. Panels keep generating at gradually reduced output, and many systems from the 1990s are still running.
What is the most common solar failure?
Inverter failure, usually between years 10 and 15. Panels themselves rarely fail; when they do it is generally traceable to installation quality.
Does hot weather shorten panel life?
Heat reduces instantaneous output by about 0.3-0.4% per degree above 25C, and sustained high temperatures modestly accelerate degradation. It affects efficiency far more than lifespan.
Related guides
General information, updated 2026-08-22. Not financial, tax or engineering advice.