How Long Do Solar Panels Last? Lifespan & Warranty
Panels last 25–30 years, but inverters and batteries don't. What each warranty actually covers, and how to make your system last longer.
Rainbow Solar Energy Team
6 min read
Updated
In this article
Key takeaways
- Good solar panels last 25–30 years and keep producing after that, at lower output.
- Panels lose about 0.4–0.6% output a year, giving 80–87% of original output at 25–30 years.
- Inverters usually last 10–15 years and lithium batteries about 10 years.
- Check both the product warranty (defects) and the performance warranty (output).
Rooftop solar is a 25-year investment, so how long each part lasts decides your real return. Here is what to expect from every component.
Lifespan of each component
| Component | Typical life | Typical warranty |
|---|---|---|
| Solar panels | 25 – 30+ years | 10–12 yr product, 25–30 yr performance |
| String inverter | 10 – 15 years | 5 – 10 years |
| Lithium (LFP) battery | 8 – 12 years | 5 – 10 years |
| Lead-acid battery | 3 – 5 years | 1 – 3 years |
| Galvanised structure | 25+ years | Varies by installer |
| Cables & safety gear | 20 – 25 years | Varies |
How much do panels degrade?
All panels slowly lose output. Expect about 1–2% in the first year, then roughly 0.4–0.6% a year. TOPCon panels typically degrade a little slower than Mono PERC.
| Year | Output (Mono PERC, approx.) | 3 kW system, units/year (Tamil Nadu) |
|---|---|---|
| 1 | 98% | ~4,270 |
| 10 | ~93% | ~4,050 |
| 20 | ~88% | ~3,830 |
| 25 | ~85% | ~3,700 |
Our savings calculator already includes yearly degradation in its lifetime savings.
Product vs performance warranty
- Product warranty (10–12 years): covers manufacturing defects like delamination, broken junction boxes or frame failures.
- Performance warranty (25–30 years): guarantees the panel will still give a set percentage of its rated output, typically 80–87% at the end.
- Inverter warranty (5–10 years): often extendable. Ask before you buy.
- Installation workmanship: covers leaks, structure and wiring. Ask your installer how long they cover it.
Keep your invoice, panel serial numbers and commissioning report safe. Warranty claims usually need all three.
How to make your system last longer
- Clean panels regularly with soft water; see our cleaning guide.
- Keep the inverter in a shaded, ventilated spot away from rain.
- Check the monitoring app monthly and act on sudden drops.
- Get a yearly electrical and earthing check, especially after the monsoon.
- Don't walk on panels or let anyone hang things from the structure.
Built to last 30 years
Tier-1 panels with a 30-year warranty, galvanised structures and a team that stays with you after installation.
What happens after 25 years?
Panels don't stop working at 25 years. Many keep producing 80% or more for years after. Eventually they can be replaced and recycled. By then, your system will have paid for itself several times over; see is rooftop solar worth it.
Written by our solar engineers and subsidy specialists, who design and install rooftop systems for homes, societies and businesses across Tamil Nadu. Figures are indicative and reviewed regularly; your free site survey gives exact numbers for your roof.
