How much output panels lose each year
Panels lose output slowly. Manufacturers set a guaranteed curve in their performance warranty: a larger drop in year one, then a steady small loss each year. The figures below are from the published Australian warranty terms of common models.
| Panel | Performance warranty | Guaranteed output at end |
|---|---|---|
| Jinko Tiger Neo | 30 years | 87.4% at 30 years |
| Canadian Solar TOPHiKu6 | 30 years | 87.4% at 30 years |
| LONGi Hi-MO X6 | 25 years | about 89% at 25 years |
| REC Alpha Pure-RX | 25 years | 92% at 25 years |
| Maxeon | 40 years on eligible installs | 88.3% at 40 years |
In practice, a well-made panel at 25 years still produces most of what it did when new. A 6.6 kW system that makes about 9,121 kWh in its first year in Sydney would still make roughly 90% of that by its mid-20s on these warranty curves.
Product warranty and performance warranty
Product warranty
Defects- Covers faults in materials and manufacture
- 12 to 25 years on most current panels
- Does not cover storm damage or poor installation
Performance warranty
Output- Guarantees a minimum output each year
- 25 to 30 years is standard
- Claims need test results
- Only as good as the company behind it
Inverters and other parts
The inverter does the hardest work and runs hot, so it usually fails first. Warranties are about 10 years for most string inverters, 12 for SolarEdge and 25 for Enphase IQ8 microinverters in Australia. Isolators, cabling and mounting should last decades if installed well, but storms and pests can damage them.
Watch your output
A sudden drop usually means an inverter fault or a tripped isolator. See solar monitoring.
Keep the paperwork
Warranty claims need the panel serial numbers, invoice and compliance certificate.
Get an inspection after storms
Hail, wind and water can damage panels and isolators. Use a licensed electrician.
When panels reach the end of their life
Old panels are often still working when they are replaced, usually because the owner wants a bigger system or a new inverter. Ask your installer how they will remove and recycle the old panels. National rules for solar panel recycling were still being developed in 2026, and some states restrict e-waste going to landfill.
Common questions
Most current panels have performance warranties of 25 to 30 years, and a few premium brands offer 40. Many keep working beyond their warranty at a gradually lower output.
Under typical current warranties, about 1 to 2% in the first year and about 0.25 to 0.4% a year after that, depending on the model.
Probably once over the life of the panels. Most string inverters carry around 10 years of warranty, though many last longer.
Sources
Warranty terms come from manufacturer warranty documents for Australia. Output uses Clean Energy Regulator zone ratings. Last checked October 2026. Prices include GST unless we say otherwise.