How Long Do Solar Panels Last? Degradation Rates in 2025 Compared
Last Updated: 5th Jun 2025 Fact-checked by Ronald Brakels
Put quality solar panels on your roof, and you can expect them to last for decades with only minor and gradual deterioration in power output over time. But despite being slow, solar panel degradation is still a concern. It has a modest effect on long-term energy production and savings, and – perhaps most importantly – if a reputable manufacturer promises low degradation rates for their panels, it indicates they’re really well-made and unlikely to have anything go wrong with them.
Solar panels have product warranties that cover defects in materials and manufacturing, and also performance warranties that promise they won’t degrade by more than a specific amount per year. These days, most product warranties are for 25 years, while performance warranties are usually for 25 or 30 years.
So long as they’re from a manufacturer you can trust, you can be reasonably confident panels won’t degrade by more than the maximum amount their performance warranty allows. You can see which manufacturers we consider trustworthy by checking out our recommended chart. Because there’s a margin of safety, panels will typically degrade by less than the maximum amount.
The Longest-Lasting Solar Panels in 2025
The table below has a range of panels available in Australia from reliable manufacturers. It gives the maximum amount of degradation their performance warranties allow for each year after the first. This degradation rate is given as a percentage of the panel’s original capacity.
| Panel | Manufacturer | Product Name | Degradation rate ▼ | Power Output Warranted at 25 Years | Approx. Cost per Panel (AUD) |
|---|---|---|---|---|---|
| REC Alpha Pure-RX | 0.25% per year | 92% | $290 | |
| SunPower Maxeon 3 | 0.25% per year | 92% | $190 | |
| Aiko Neostar 2P | 0.35% per year | 90.6% | $149 | |
| Winaico WST-NGX-D3 | 0.4% per year | 89.4% | $198 | |
| Jinko Solar Tiger Neo (440W) | 0.4% per year | 89.4% | $125 | |
| Longi Hi-MO 6 Scientist | 0.4% per year | 88.9% | $130 | |
| Solahart Silhouette series | 0.4% per year | 89.4% | $130 | |
| Risen TOPCon | 0.4% per year | 87.4% | $130 | |
| Tindo Walara | 0.4% per year | 87.4% | $260 (assembled in Australia) | |
| SolarEdge Smart Panel | 0.55% per year | 84.8% | $290 (includes optimiser) | |
|
| Risen Titan S (440W) | 0.55% per year | 84.8% | $135 |
The very best panels only lose up to 0.25% per year, while the worst on the list only loses up to 0.55% per year.
Table of Contents
- The Longest-Lasting Solar Panels in 2025
- What Is A Good Degradation Rate for a Solar Panel?
- Year 1 vs. Years 2–25: Why the First Drop Is Bigger
- What Causes Solar Panel Degradation?
- Why Degradation Matters Over Time
- Are the Slowest-Degrading Panels Always the Best?
- Related Guides and Resources
What Is A Good Degradation Rate for a Solar Panel?
At the moment, in 2025, if your panels are from a quality manufacturer, you can typically expect them to have a warranted annual degradation rate of 0.4% of their original capacity or less. If it’s higher than this, it can still be an acceptable panel, but be prepared for it to lose slightly more output over time.
While the maximum warranted loss for most panels now going on Australian roofs is 0.4%, you can do a little better by getting Aiko panels, which are 0.35%, and if you’re willing to pay for a premium panel such as REC or SunPower Maxeon, it can be 0.25%.
These low rates are examples of how solar panels have improved. Five years ago, permitted rates of capacity loss were often around 0.7% per year.
Year 1 vs. Years 2–25: Why the First Drop Is Bigger
The usual annual rate of degradation is low, but performance warranties allow for a steeper output drop in their first year. This is usually either 1% or 2%, but for some panels it’s 1.5%.
This is mainly due to Light-Induced Degradation (LID), which affects panels during their first day or two in sunlight, but then stops. How bad it is depends on the type of panel.
- P-type panels, which used to be common but now rarely go on roofs, typically allow 2% degradation in their first year to account for LID.
- N-type panels, which are now the most common sort going on roofs, are mostly immune to LID and typically allow for 1% degradation in their first year or sometimes 1.5%.
So while a panel can take a small hit to output in its first year, you can expect the deterioration in subsequent years to be very gradual.
What Causes Solar Panel Degradation?
Being clamped to a rack on a roof and exposed to the elements is a tough life. Solar panels can expand and contract with changes in temperature, be flexed by wind, soaked by rain, and possibly pounded by hail. This results in the build-up of initially very minor damage over the years, which can include microcracks in solar cells and damage to solder joins. Both problems can reduce current flow. Well-made panels with lower rates of degradation are better able to resist these effects and so build up damage at a slower rate.
Why Degradation Matters Over Time
While the degradation rates of modern panels are low, the losses will build up and affect your system’s lifetime energy yield. If you choose a premium panel with a performance warranty that allows 1% degradation in the first year and 0.25% in subsequent years, and it degrades at the maximum allowed rate, it will have 92% of its original power output after 25 years.
If you instead used a panel with a performance warranty that allows 2% degradation in the first year and 0.5% in subsequent years, and it degrades at the maximum allowed rate, it will have 86% of its maximum power output after 25 years.
The increased rate of degradation results in the second panel producing 4.2% less energy over 25 years. Because the energy loss gets worse over time, half of it occurs after year 17.
Because panels are unlikely to degrade at their maximum allowed rate, the second panel is more likely to produce roughly 3% less energy over 25 years. So while doubling the warranted degradation rate does make a difference, it doesn’t make a large one, especially over the first 10-15 years.
Are the Slowest-Degrading Panels Always the Best?
All else equal, the lower the warranted degradation rate, the better. But things aren’t always equal. If you want panels with the lowest warranted degradation rates, you’ll have to pay more for a REC or SunPower Maxeon panel, and you may not consider the modest expected improvement in energy production to be worth the extra cost.
How Much Can Slower-Degrading Panels Save You?
Let’s compare two 10 kW systems, one consisting of typical panels and one consisting of premium panels:
| Typical Panel | Premium Panel | |
|---|---|---|
| Degradation in year 1 | 2% | 1$ |
| Degradation afterwards | 0.4% per year | 0.25% per year |
| Total energy over 25 years | ~340,000 kWh | ~350,000 kWh |
| Estimated savings | $34,000 | $35,000 |
In 25 years, the premium panel system saves you about $1,000. Because it takes time for the effects of degradation to build up, most of the savings occur later in the panel’s life:
| Years Passed | Cumulative Extra Savings (Premium vs. Typical) |
|---|---|
| year 5 | $95 |
| year 10 | $245 |
| year 15 | $450 |
| year 20 | $710 |
| year 25 | $1,020 |
| year 30 | $1,390 |
| year 35 | $1,810 |
| year 40 | $2,290 |
In the first 20 years, the premium panel system will only save you around $700 more in electricity savings than the typical panel system. However, in the next 20 years, they save an additional $1,600.
Note: We have assumed the maximum degradation that performance warranties allow, but most manufacturers include a safety buffer. Therefore, real-world degradation is likely less.
The takeaway
- If you’re only planning to stay in your home 10 years or less, premium panels may not pay off.
- If you’re in it for the long haul — or want a system that might still be working in 40 years — it’s worth considering the slowest-degrading panels from reputable brands.
Related Guides and Resources
- Solar Panel Comparison Table: Compare specs, prices, and warranties of Australian solar panels by degradation rate, efficiency, cost and more.
- Solar Panel Reviews: Independent reviews and customer ratings for dozens of panel brands available in Australia.
- Most Efficient Solar Panels in 2025: Learn about the highest efficiency panels on the market today.
- Best Solar Panels in 2025: Insights from Aussie installers on top panel brands for performance, reliability and value.
- Beginner’s Guide to Solar Panels : Everything you need to know about buying and installing solar panels in Australia.