How long do solar panels last? The answer with a document behind it

The honest answer to "how long do solar panels last" is a term, not an average. On the panel brands we have read the documents for, the product warranty runs 25 to 30 years, with one brand sitting at 12 unless somebody registered it in time. On the inverters, it runs 10 to 12. Those are the numbers somebody at the manufacturer signed and can be held to. Everything longer than that is a hope, and everything you have read about a "typical lifespan" is somebody's estimate with nothing enforceable underneath it.

So the useful version of the question is not how long your panels will last. It is: for how long is somebody other than you responsible if they do not.

The guaranteed floor, brand by brand

This is what our catalogue holds, taken from each manufacturer's own published warranty document, with the date it was read printed on every brand page.

Two things fall out of that table immediately.

The first is that the honest floor for a modern panel is a quarter of a century of manufacturer responsibility, and on Jinko's Tiger Neo line it is three decades. That is not marketing. It is a liability a company put in writing.

The second is Silfab, which is the whole reason this site exists. Two panels can both be sold as "25 year warranty" and only one of them will still be a 25 year warranty in year 13, because Silfab's product cover is 12 years unless the installation, site and product details were registered through Silfab's portal within 180 days of purchase. Nobody sends a reminder. The panel looks identical either way. See the Silfab warranty page and what missing the 180 day window costs.

What "last" actually means, and why the answer keeps changing

The question hides three, and every page that gives you a single number has quietly picked one without telling you.

Still producing something. A panel does not switch off on the last day of its term. Nothing in the warranty says it will stop, and nothing says it will keep going.

Still producing enough to be worth the roof space. That is a judgement about your electricity price, not a property of the panel.

Still somebody else's problem. This one has a date on it, and the date is in the table above. It is the only one with a document behind it, which is why it is the only one we will put a number on.

What degradation actually means

Panels get weaker with age. That is expected, it is normal, and it is written into a separate warranty from the one in the table above.

A performance warranty is written in three parts, whatever the brand:

1. A first year figure. Panels lose slightly more in year one, so the document names a percentage of rated power the panel will still make at the end of it.
2. An annual rate after that. A maximum loss per year for the rest of the term.
3. An end of term floor. The percentage of rated output guaranteed at the final year.

Put those together and you get a gently sloping line from just under 100 percent down to a floor at year 25 or 30. That line is the promise. Anything above it is not a claim, however disappointing the number on your app looks.

We are not going to publish a single industry degradation figure here, because there is not one. The numbers differ by brand, by product line and by model year, and they are printed on the datasheet for your exact panel. Get that datasheet and put your reading against the curve with the degradation calculator. The longer version is in solar panel degradation rate: what is normal, and when it is a claim.

The important structural point for the lifespan question: on Canadian Solar's current residential modules the performance warranty runs 30 years while the product warranty runs 25, and on Silfab the performance warranty runs 30 years whatever happens to the product cover. The manufacturers themselves expect the glass to outlive the defect cover.

How long do solar inverters last?

Shorter. Much shorter, and the manufacturers say so themselves.

Enphase is the outlier, and it is a deliberate one: the IQ8 microinverter carries 25 years from Enlighten activation, which puts it in panel territory rather than inverter territory. Every other inverter brand in the catalogue sits at 10 or 12.

The full comparison is on the inverter warranty page.

Why the inverter dies first

You do not need a failure statistic to see this coming. The manufacturers have already priced it for you.

A panel is glass, laminate, cells and a frame, with no moving parts, no cooling and no firmware. An inverter is power electronics doing a conversion job every daylight hour for a decade, with heat to shed and software to keep current. The companies that build both have written 25 to 30 years on one and 10 to 12 on the other.

That gap is the most important fact about owning a solar system and the one nobody is told at the point of sale. A 25 year array is bolted to a component with a 10 year promise. Plan for at least one inverter replacement, possibly two.

What that replacement involves, and how to check whether you are actually paying for it, is in solar inverter replacement cost and solar inverter repair: claim first, pay second.

Your panels are older than your system

Here is the part that quietly shortens everybody's answer.

The term does not always start on the day the panels went on your roof. From the documents we have read:

• Jinko: delivery, or 180 days after manufacture, whichever is earlier.
• Trina: installation, or three months after delivery, whichever comes first.
• Q CELLS: the end customer invoice date, in the terms we could read.
• Silfab: delivery, for the product warranty.
• SolarEdge, on the inverter side: the earlier of installation or four months from shipment.

So a panel that sat in a distributor's warehouse for a year is a year into its warranty before it ever produces a watt, and your cover ends a year earlier than your install date suggests. Nobody writes to tell you. The warranty deadline calculator will place the real date from the dates you actually have.

What shortens the life of the warranty

The term in the table is the best case. Several brands attach a condition that has to stay true, with no deadline attached and no notification when it breaks.

GoodWe. The 10 year inverter term holds only while the inverter is connected to the SEMS portal and uploading generation data, and on a hybrid running a Lynx battery both serials have to be registered. Miss either and the term is five years instead of ten. A changed wifi password in year two surfaces as a denied claim in year seven. See the GoodWe SEMS trap.

Tesla. Powerwall's 10 year term needs the unit to stay connected to the internet. If the connection drops and is not restored within 45 days of Tesla's written request, cover ends at 48 months. See Powerwall connectivity as a warranty condition.

REC. ProTrust, the cover on the sales brochure, exists only where an REC Certified Solar Professional installed the system and registered it in ProPortal or the SunSnap app. If that did not happen, the system falls back to the standard product warranty and nothing can be done about it later.

Fronius. The free 10 year Warranty Plus depends on registration in Solar.web within 30 months of delivery ex works.

The general shape is covered in warranty conditions, not deadlines.

What shortens the life of the panel

Distinct question, different answers, and the important thing is that most of them are not the manufacturer's problem.

A product warranty covers the panel being defective: delamination, a failed junction box, a corroding frame, a cell that cracked with no external cause. It is defect cover. It is not damage cover.

Which means hail, a branch, someone walking across the array during a roof repair, water getting in where a cable gland was not done properly, or a mounting system that was never right are all real ways a panel's working life ends early, and none of them is a claim against the panel maker. They belong to your insurer or to the company that did the installation, whose workmanship warranty is a completely separate promise with a completely separate length. Product, performance and workmanship warranty sorts out which is which.

The one maintenance habit that genuinely protects the manufacturer term is boring: keep the invoice, the delivery paperwork, the serial numbers and any registration confirmation together, for decades. Several brands in the table make the invoice or the delivery date the thing that sets the start of the term, and Jinko wants the warranty certificate plus the purchase and installation invoices before it will look at a claim. Solar panel maintenance: what actually needs doing covers the rest of it.

When replacement beats repair

Panels are rarely repaired. A cracked panel, a delaminated laminate or a failed junction box is a swap, not a fix, and the interesting decision is whether the swap is a claim.

Two rules of thumb that hold up.

If it is inside the term and it is a defect, claim it before you price it. The part should be free. The labour almost certainly is not, and across the panel brands in our catalogue only REC's Alpha Pure-R line carries any labour cover at all, at 20 years. Enphase in the United States pays $200 per truck roll plus $25 per replaced microinverter, and that is the only stated labour rate in the whole catalogue. Everyone else pays for the part and nothing toward the visit.

If it is out of term, ask what the new term would be. Replacing an inverter that is at the end of its 10 years buys you a fresh 10 or 12 year promise, at a time you choose, instead of an outage in the middle of winter. The inverter replacement cost tool walks the line items, and the truck roll cost tool shows what the visit itself is worth against what a brand reimburses.

What the 25 year warranty does and does not promise

It does promise that if the panel is defective within the term, the manufacturer will deal with the panel. It promises the performance floor on the datasheet curve, separately and usually for longer. It promises those things to whoever the document says it promises them to, which is usually the original owner and, on transfer, the new one if the paperwork follows the house.

It does not promise that the panel will still be producing its rated output. It does not promise that anyone will pay to get on your roof, unless you bought REC or you are covered by an Enphase labour programme. It does not promise the manufacturer will still exist: if the company is gone, the term is a claim against a company in liquidation, which is a different thing entirely. What happens to your warranty when a manufacturer goes under is worth reading before you weight a brand's warranty length heavily in a buying decision.

And it promises nothing at all about your installer's work. That is the workmanship warranty, and it is the one that disappears when a local company closes. Taking on orphaned solar customers explains what survives.

The short version

1. Panels in our catalogue carry 25 to 30 years of product cover. That is the floor with a signature on it.
2. Inverters carry 10 to 12, except Enphase IQ8 microinverters at 25. Expect to replace the inverter at least once.
3. Your term probably started before your install date. Find the delivery or shipment date and use the deadline calculator.
4. Check whether your brand has a condition attached, especially GoodWe, Tesla, REC, Fronius and Silfab.
5. Keep the invoice, the delivery paperwork and the serials. On several brands they are the term.

Every brand we have checked is at warranties by brand, with the date the document was read on the page.