Solar & Inverter Warranties Explained: What's Really Covered

A solar quote will wave big warranty numbers at you — "25-year panels", "10-year inverter". Those headlines hide a lot. There are usually three separate warranties on a rooftop system, each with different lengths, different coverage and different ways to fail you. Because we sell and install nothing, we have no reason to talk these up or down — here's what the paperwork actually means.

The three warranties on every system

Treat these as separate documents, because legally they are:

• Panel product warranty — covers manufacturing defects in the panel itself (delamination, junction-box failure, internal faults). Commonly 10–25 years depending on the manufacturer.
• Panel performance warranty — guarantees the panel still produces a stated minimum percentage of its rated output after a set number of years. This is a degradation promise, not a defect promise, and it's almost always the longest number on the page.
• Inverter warranty — covers the inverter, typically the shortest of the three. The inverter is the component most likely to need replacing within the system's life, so this number matters more than the glamorous panel figures.

There's also a fourth, often-forgotten one: the installer's workmanship warranty, covering the actual install (racking, wiring, roof penetrations, water ingress). If the installer goes under, this is the warranty that evaporates.

Product vs performance — why the difference bites

A "25-year panel" usually means a 25-year performance warranty and a much shorter product warranty. Performance cover only pays out if output drops below the guaranteed curve — and manufacturers build in expected annual degradation, so slow fade is "normal", not a defect. To claim, you generally have to prove the panel is underperforming the guaranteed figure, which means commissioning independent output testing at your own cost first.

The fine print that quietly voids claims

This is where most claims die. Watch for:

• Pro-rata payouts. Many warranties reduce the payout each year. A panel failing in year 12 of a 25-year term may return a small fraction of its value — not a free replacement.
• Labour and freight excluded. The panel might be "covered", but you pay for the electrician, scaffolding, crane and shipping to get it swapped. On a roof, that can exceed the hardware cost.
• "Local presence" risk. A warranty from a manufacturer with no Australian office or local agent is only as good as your ability to chase an overseas company. If the brand exits the Australian market, the paper is worthless.
• Installer-dependent conditions. Warranties are frequently voided by non-approved components, DIY cleaning methods, or using an uncertified electrician for later work.
• Maintenance and inspection clauses. Some require documented periodic inspections. Miss them and the manufacturer can decline.
• Serial-number and registration rules. A few require online registration within a window of installation or cover is reduced.

Your strongest protection isn't the warranty card

Under the Australian Consumer Law, goods must be of acceptable quality and last a reasonable time — and these consumer guarantees exist on top of any manufacturer warranty, regardless of what the warranty card says. A panel failing well before its reasonable life can be a consumer-guarantee issue even if the written warranty tries to exclude it. The practical catch: enforcing ACL rights against a vanished importer is still hard, so the financial strength and local footprint of both the manufacturer and the installer matter more than the printed years.

Does the warranty change the maths?

Partly. Because federal Small-scale Technology Certificates (STCs) are already baked into the system price you're quoted — an indicative 6.6kW system runs roughly $4,000–$6,500 after STCs, and 10kW around $6,000–$10,000 — the warranty doesn't change your upfront cost. What it changes is lifetime risk. If an inverter with a short warranty needs replacing out of pocket before the system pays back, that's a real hit to your return. When you're adding a battery, the same discipline applies: the federal Cheaper Home Batteries discount (an STC-based reduction worth roughly $250–$300 per usable kWh on indicative figures) lowers the entry price, but a battery's cycle warranty and retained-capacity guarantee deserve the same scrutiny as any panel. Confirm the exact current figures for your situation, as these schemes step down on scheduled dates.

Here's the honest beat: a longer warranty is not automatically worth paying more for. A premium panel with a 25-year product warranty from a brand likely to still be here matters; a 25-year warranty from an unknown importer may be worth less than a shorter one from a company you can actually reach. Pay for the backing, not the number.

We don't sell panels, inverters or batteries, and we don't take installer referral fees — so we've no stake in which brand you choose. Our only job is to read the fine print with you and tell you whether the system, and its warranty, genuinely stack up for your roof and your bills.

Figures in this guide are current at the date of publication and indicative only — rebate and certificate values change over time (federal battery certificates step down each January and July), and state schemes are amended often. Confirm the current numbers for your situation before you commit. This is general information, not personal financial advice.