Most quality solar panels in Australia will continue producing electricity for 25 to 30 years, and often longer. They do not suddenly stop working at the end of a 25-year warranty. Their output usually declines gradually over time.
The more useful question is not, “How old are my panels?” It is, “Are they still producing enough electricity to justify keeping?” A 20-year-old system that is meeting expectations may be worth leaving alone. A newer system with physical damage, inverter faults or poor output needs attention sooner.
How long do solar panels last in Australia?
A well-made, correctly installed solar panel system can commonly operate for 25 to 30 years or more. The panels themselves have no moving parts, which is one reason they tend to outlast other parts of the system.
Australian conditions do make the original equipment and installation choices matter. Heat, high UV exposure, coastal salt air, roof design and ventilation, mounting quality and workmanship all affect how a system ages. In South Australia, for example, panels need to cope with long periods of heat and intense sun, not just perform well in a laboratory test.
| Component | Typical service life | What to expect |
|---|---|---|
| Solar panels | 25–30+ years | Gradual reduction in output over time |
| String inverter | Often 10–15 years | Commonly replaced before the panels |
| Microinverters | Often longer, varies by brand | Warranty periods can be longer, but check the exact product |
| Home battery | Often around 10 years | Life depends on use, cycles, temperature and warranty terms |
These are guides, not expiry dates. A good system can outlast them, while a poor installation can run into problems earlier.
What is solar panel degradation?
Solar panel degradation is the gradual reduction in a panel’s generating capacity as it ages.
Every panel loses some output over time. This is normal. What matters is whether the loss is within the performance warranty and whether the system is still producing close to what it reasonably should for its size, orientation and location.
Many panel performance warranties promise a minimum output level, often around:
- 90% at year 10
- 80% at year 25
That does not mean every manufacturer offers the same terms, or that every panel loses output at the same rate. Check the performance warranty for the exact model installed on your roof, including how output is measured and what exclusions apply.
A panel may still be physically intact but underperform because of shading, soiling, inverter issues, failed optimisers, damaged cabling or a change to the property around it. That is why a low production figure is not enough, on its own, to blame the panels.
What usually needs replacing first?
Solar inverters
The inverter is usually the first major component likely to need replacement. It converts the DC electricity made by your panels into AC electricity your home can use.
String inverters commonly come with warranties of five to 10 years, though many operate beyond that. If a 12-year-old solar system has stopped producing, the inverter is often the first thing to investigate, not the panels.
Microinverters can have longer warranties, but they are still electronic components installed in a hot roof environment. Warranty length, access requirements and replacement labour should all be checked before buying.
Batteries
A battery has its own life cycle and should not be confused with the solar panel lifespan. Most home batteries have a warranty around 10 years, usually tied to both time and a minimum retained capacity after a stated number of cycles.
A battery that is no longer suitable for your household does not mean the solar panels need replacing. It may simply mean the battery needs repair, replacement or a rethink based on how your household now uses electricity.
When should you replace solar panels?
Do not replace a solar system simply because it is 20 or 25 years old. Start with the numbers and the condition of the system.
Replacement can make sense when:
- panels are cracked, water-damaged or otherwise physically damaged
- output is materially below what the system should reasonably produce
- a panel fault may be covered by a product or performance warranty
- the roof needs replacement and removing the system creates an opportunity to upgrade
- the existing system is too small for current electricity use, an EV, a battery or electric hot water
- the old system uses equipment that is difficult or uneconomical to repair
A panel upgrade may be financially sensible, but that does not make it automatically necessary. If your roof is due for replacement, it is worth comparing removal and reinstallation costs with the cost of an upgrade at the same time. Otherwise, compare the expected extra generation against the inverter condition, your daytime electricity use, export limits, battery plans and the cost of the upgrade.
Replace, repair or keep? A simple checklist
| If this is happening | The sensible first step |
|---|---|
| Production has fallen sharply | Check monitoring, weather, shading and inverter error messages |
| The inverter has failed but panels are sound | Price an inverter replacement before replacing the array |
| One or two panels are damaged | Ask for an inspection and warranty assessment |
| The roof needs major work | Compare removal and reinstallation costs with an upgrade |
| Your system is producing normally | Keep it and continue monitoring |
| Your household now uses much more power | Assess an expansion or replacement based on current usage |
An inspection should come before a replacement quote. I have seen systems written off as “old” when the actual issue was a failed inverter, loose connection or new tree shading.
Can unused solar panels be stored?
Yes, but they need to be stored properly.
Uninstalled panels do not degrade because they are not generating electricity. Poor storage can still damage them through moisture, impact, incorrect stacking or damage to packaging.
Keep unused panels dry, protected from knocks and stored in their manufacturer-approved packaging where possible. Check the manufacturer’s storage instructions before holding panels for a long period, particularly if you want to preserve warranty coverage.
How to check whether an older solar system is still performing
Start by comparing current generation with previous years. Use the same months where possible, because weather and seasonal daylight make a big difference.
Then check:
- inverter monitoring data and fault messages
- visible panel damage, loose mounting or water ingress
- new shading from trees, extensions or neighbouring buildings
- dirty panels or heavy debris build-up
- whether the inverter is switching off during the day
- electricity use changes that may make a once-suitable system feel too small
Avoid climbing onto a roof or opening electrical equipment yourself. Arrange an inspection with an appropriately qualified solar or electrical professional if the system is underperforming or showing faults.
Warranties and consumer rights
Solar warranties are often discussed as though they are one thing. They are not.
| Type of cover | What it usually relates to |
|---|---|
| Product warranty | Defects in the panel, inverter or battery itself |
| Performance warranty | Minimum warranted panel output over a stated period |
| Workmanship warranty | Problems caused by installation work |
| Australian Consumer Law guarantees | Automatic legal rights that apply separately from voluntary warranties |
Under Australian Consumer Law, consumer guarantees apply to solar products and installation services and cannot be excluded by warranty terms. The ACCC says that where one business sold both the system and installation, that business is generally responsible for helping provide a remedy, even where it used a subcontractor for the installation. Start with the retailer that supplied the system rather than being sent straight to the manufacturer. Read the ACCC’s solar panel and home battery guidance.
Keep your proposal, invoice, commissioning documents, warranty certificates and monitoring records. They make a fault or warranty discussion much easier.
How to extend solar system life
A solar system does not need constant attention, but ignoring faults is expensive.
Keep an eye on monitoring, particularly after storms or when electricity bills change unexpectedly. Deal with inverter warnings promptly. Keep panels clear of persistent shading and debris where this can be done safely. Use qualified professionals for inspections, repairs and electrical work.
The best way to get a long service life is to begin with a system designed for the roof, local conditions and household’s actual electricity use. That means looking beyond the panel’s headline wattage to installation quality, inverter selection, ventilation, warranty support and who will still answer the phone if something goes wrong. It also means recognising that the people making energy decisions matter as much as the equipment itself.
Before replacing anything, it is worth getting a clear view of your system’s condition and likely options, rather than assuming age alone is the problem.
FAQs
How long do solar panels last in Australia?
Quality solar panels commonly operate for 25 to 30 years or more, with output declining gradually over time.
Do solar panels stop working after 25 years?
No. Twenty-five years is commonly a performance-warranty period, not an expiry date. Many panels continue generating electricity after that point.
How much do solar panels degrade each year?
There is no universal rate that applies to every panel. Check the warranted output for the specific panel model rather than relying on one generic percentage.
When should I replace my solar panels?
Replace them when they are damaged, materially underperforming, uneconomical to repair, unsupported by warranty, or when an upgrade has a sound case based on your electricity use and system condition.
What usually fails first in a solar system?
The inverter often needs replacement before the solar panels.
Can solar panels be stored before installation?
Yes. Store them dry, protected from impact and moisture, and in line with the manufacturer’s instructions.