What Happens to Solar Panels After 25 Years? Lifespan, Degradation and Upgrade Options in Perth
Quick Answer: Solar panels don’t stop working after 25 years — they continue generating electricity, just at reduced efficiency. Most quality panels still produce 80-85% of their original output at 25 years. Perth homeowners with ageing systems have three options: keep them running, upgrade to newer high-efficiency panels, or add a battery to maximise what the existing system produces.
If you’re one of the many Perth homeowners who installed solar 10-15 years ago during the early boom, you might be wondering how much longer your panels will last. The 25-year warranty figure gets thrown around a lot, but it doesn’t mean your panels have an expiry date.
How Solar Panels Degrade
Solar panels degrade through a process called light-induced degradation (LID) and potential-induced degradation (PID). In practical terms, panels lose approximately 0.3-0.5% of their output per year. Perth’s dry, sunny climate is actually gentler on panels than humid tropical environments.
| Panel Age | Expected Output | 6.6kW System (Perth) |
|---|---|---|
| Year 1 | 97-99% | ~10,100 kWh/yr |
| Year 10 | 92-95% | ~9,600 kWh/yr |
| Year 15 | 89-92% | ~9,200 kWh/yr |
| Year 20 | 86-90% | ~8,900 kWh/yr |
| Year 25 | 80-85% | ~8,400 kWh/yr |
| Year 30+ | 75-80% | ~7,900 kWh/yr |
A 6.6kW system installed in 2001 and still running in 2026 at 85% efficiency is still producing roughly 8,700 kWh per year — saving you $2,700+ annually at current Synergy rates.
When Does Upgrading Make Sense?
Consider upgrading if:
- Your panels are producing less than 70% of original output (monitor via your inverter app)
- Your inverter has failed and replacing it costs more than 40% of a new system
- Your panels are small (e.g., 250W) and modern panels (400W+) would generate significantly more from the same roof space
- You want to add a battery and your current system is undersized
- Your current system has no monitoring — modern systems include real-time monitoring as standard
Worth knowing: If your inverter has failed but your panels are still performing well, you might only need an inverter replacement ($1,500-$3,500) rather than a full system upgrade. A qualified installer can test your panels and advise.
Solar Panel Recycling in Australia
As the first wave of Australian solar installations reaches end of life, panel recycling is becoming increasingly important. Most solar panels are 75-80% glass, 10% aluminium, and contain small amounts of silicon, copper, and silver — all recyclable. Several Australian companies now offer panel recycling, including Reclaim PV and PV Industries. Your installer can usually arrange removal and recycling of old panels when installing a new system.
Frequently Asked Questions
Should I replace my 10-year-old solar panels?
Probably not — 10-year-old panels typically still produce 92-95% of their original output, which means they’re working fine. The more common issue at 10 years is the inverter approaching end of life (string inverters last 10-15 years). If your inverter needs replacing, that’s the ideal time to consider whether adding panels or a battery makes sense. Talk Energy can test your existing panels’ output to determine whether replacement or augmentation is the better investment.
Can I add new panels alongside my old ones?
Yes, but with caveats. New panels and old panels produce at different voltages and efficiencies, so they can’t be wired on the same string. Your installer will typically put new panels on a separate string or use microinverters/optimisers to manage the mismatch. A hybrid inverter can manage both old and new panel arrays effectively. This is a common and cost-effective approach for Perth homeowners who want more capacity without replacing their entire system.
What happens to solar panels at end of life?
Solar panels can be recycled — up to 90% of materials are recoverable. In Australia, companies like Reclaim PV specialise in solar panel recycling. Panels should never go to general landfill as they contain small amounts of lead and other materials. When Talk Energy installs a replacement system, they can arrange responsible removal and recycling of old panels as part of the upgrade process.
Talk Energy offers full system upgrades, partial upgrades (inverter-only), and battery additions for older systems. Get a Free Quote or call (08) 6255 5914.
Talk Energy: Perth’s most trusted solar and battery installer, with 250+ five-star reviews and a 20-year workmanship warranty.
