How Long Do Solar Panels Last in Australia?

Solar panels don't just stop working one day. They gradually produce less electricity over time through a process called degradation. Think of it like a car engine slowly losing power over hundreds of thousands of kilometres.

For standard monocrystalline panels, degradation runs at about 0.5% to 1% per year. That means after 25 years, a typical panel will still produce somewhere between 75% and 87.5% of its day-one output. That's a significant amount of electricity, and well above the point where most people would consider replacing them.

Premium panels do even better. Brands like SunPower and REC advertise degradation rates as low as 0.25% per year. At that rate, you're looking at over 93% output after 25 years. Some early SunPower installations from the 1990s are still producing above 90% of their original capacity today.

So the technology itself is proven. Panels can and do last a very long time. The question is whether yours will.

In January 2026, researchers at the University of New South Wales published findings that shook up some assumptions about solar panel longevity. After analysing thousands of panels across Australian installations, they found that roughly 1 in 5 panels fail much faster than expected, with some lasting only half their anticipated lifetime.

That's a confronting statistic if you've just signed a contract for a new system. But context matters here. The study looked at panels across a range of quality levels and installation standards. The failures weren't random. They clustered around specific factors.

Budget panels with shorter product warranties were overrepresented in the early-failure group. So were systems with installation issues: poor mounting leading to micro-cracks, inadequate ventilation causing heat buildup, and shoddy wiring that created hotspots.

The takeaway isn't that solar is unreliable. It's that cutting corners on panel quality or installation can come back to bite you well before the 25-year mark.

Several factors determine whether your panels will be in the “still going strong at 30” camp or the “struggling at 15” group.

Solar panels come with two types of warranty, and understanding the difference is important when you're thinking about longevity.

The product warranty covers manufacturing defects, like delamination, junction box failures, and frame corrosion. Budget panels typically offer 10 to 12 years of product warranty coverage. Premium panels from brands like REC, SunPower, and QCells offer 25 years, which tells you something about the manufacturer's confidence in their product.

The performance warranty guarantees a minimum output level over time. The industry standard is 80% to 87% output at 25 years. This warranty is your insurance against excessive degradation, and it's the one you're more likely to actually use.

A word of caution: a warranty is only worth something if the company exists to honour it. A 25-year warranty from a brand that folds in 5 years gives you nothing. Choosing panels from manufacturers with a strong Australian presence, local warehousing, and a track record of honouring claims is worth the small premium. Read more in our guide to choosing solar panels.

Here's something that catches a lot of solar owners off guard. While panels can run for 25 to 30 years, your inverter, the box that converts DC power from the panels into AC power for your home, typically lasts just 10 to 15 years.

Inverters work harder than panels. They contain electronic components that deal with heat, voltage fluctuations, and constant cycling. String inverters from brands like Fronius, SMA, and Sungrow generally last 10 to 15 years. Microinverters (like Enphase) tend to last longer, often 20 to 25 years, because they run cooler and share the workload across multiple units.

Budget for an inverter replacement at around the 10 to 12 year mark. It'll cost roughly $1,500 to $3,000 depending on the size and brand. This is a normal part of owning solar, not a sign that anything has gone wrong.

When the time comes, it's also a good opportunity to upgrade. Inverter technology improves rapidly, and a new unit may offer better efficiency, smarter monitoring, and battery-readiness that your original inverter didn't have.

Solar panels don't have an expiry date stamped on the back. The decision to replace them usually comes down to practical factors rather than a fixed timeline.

You don't need to do much to keep solar panels healthy, but a little attention goes a long way.

Check your monitoring app regularly. Most modern systems have WiFi monitoring that shows daily production. If you notice a sudden drop, investigate before a small issue becomes a big one.

Keep the panels reasonably clean. In most parts of Australia, rain does a decent job, but if you live in a dusty area, near trees that drop sap, or have a bird problem, an annual clean with plain water helps. Never use abrasive cleaners or high-pressure washers on solar panels.

Trim overhanging branches. Trees grow, and what was a shade-free roof five years ago might now have a branch casting shadows for part of the day. Shading doesn't just reduce output, it accelerates localised degradation.

Book a professional inspection every 5 years or so. An electrician can check connections, look for micro-cracks with thermal imaging, and ensure everything is performing as it should. Most solar-specific electricians charge $150 to $300 for a full system health check.

Quality solar panels genuinely last 25 to 30 years, and many will keep producing useful power beyond that. The 25-year figure isn't marketing spin. It's backed by decades of real-world data from installations around the world.

But the UNSW research is a useful reality check. Not every panel lives up to its promise. The ones that fail early tend to be budget products, poorly installed, or both. Spending a bit more upfront on quality panels and a reputable installer is the single best thing you can do to ensure your system reaches that 25-year mark and beyond.

Your inverter will need replacing around year 10 to 15, and that's normal. Factor it into the overall cost of ownership and it still works out to very cheap electricity over the life of the system.

Thinking about going solar? Our rebate eligibility quiz can help you see what incentives are available in your state, and connect you with installers who won't cut corners.