Are secondhand solar panels worth it?

Been running secondhand panels for about three years now and honestly, mixed bag. Got a set of 300W Canadians for £80 each off eBay — proper bargain compared to new. They've held up fine, still churning out the claimed specs according to my Victron MPPT monitoring.

The reality though:

• No warranty is the big one. One panel started delaminating after 18 months, had to bin it
• Harder to find matching voltage/current specs if you're expanding later
• Sellers don't always know the history — salt air, mechanical stress, dodgy storage all take their toll
• Testing them before you buy is tricky unless you've got decent kit

Where I reckon it works:

Emergency backup systems where you don't need peak efficiency. Prototype setups before committing to new panels. If you've got the testing knowledge (I-V curves, thermal imaging etc).

Where I'd avoid it:

If you're after warranty peace of mind. If space is tight and you need every watt. Long-term installs where you want to max ROI.

The maths is tempting — you can get panels at 30-50% new price — but factor in time sourcing, travel collecting them, potential dead stock. Sometimes that extra £200 for new Renogy or Fogstar panels is worth the hassle saved.

Reckon most people here are comfortable DIY testing? That's really the deciding factor. What's your setup look like — grid-tied or standalone?

Grabbed some ancient 100W Kyoceras off a dismantled farm setup for next to nothing — still absolute workhorses on the motorhome after five years, degradation's barely noticeable. The real gamble is dodgy internals you can't see until they start sulking in winter, but if you've got a decent multimeter and aren't afraid of testing them properly before handing over cash, secondhand's hard to beat on price-per-watt. Just don't expect a warranty and keep your Victron MPPT ready to cope with slightly wonkier voltage curves than shiny new stuff.

I've gone down this rabbit hole twice with my van conversion setup. First time, picked up a batch of 250W Siemens panels from a caravan dismantler for £60 each — bit dodgy looking, one had a hairline crack in the frame, but they've been solid for eighteen months.

The real gamble is degradation. You genuinely don't know what you're getting. Those Canadians @CotswoldNomad mentioned are built like tanks, but I've also seen newer budget panels that've basically been abused and already losing 5-10% output before they hit your roof.

What's worked for me: grab panels from reputable dismantlers (not random sellers), check the junction boxes aren't corroded, and factor in you might only get 80-85% of original spec. Works brilliantly if you've already sized your system generously. Not worth the hassle if you're running on tight margins though.

Secondhand panels are basically the off-grid equivalent of charity shop furniture — sometimes you find a gem, sometimes you get woodworm. I've got three dodgy 150W Renogys on my garden office that spend more time generating sympathy than watts, but my mate's salvaged 200W monocrystalllines are somehow still outperforming his new panels (spite, probably). The real gamble is degradation data you'll never have — new ones come with 25-year warranties, secondhand ones come with a shrug and an eBay rating. Worth it? Only if you're comfortable being your own warranty department and can actually test them properly beforehand with a multimeter.

The real question is degradation rate vs. initial cost. Those older panels like @RetiredNurse49's Kyoceras will degrade slower per year simply because they've already taken most of the hit in year one. If they're still performing, they're stable.

Where I'd be cautious is panels that've been sat in direct sun for years without maintenance — the junction boxes and connectors corrode faster than the cells themselves. Had a dodgy batch of Canadians where the MC4s were practically cemented together.

For a shepherd's hut setup like mine, I paired secondhand 250W panels (£70 each) with a Victron MPPT to squeeze every amp out of them. The efficiency hit from age is minimal if you're already accepting smaller wattage. Just get them tested first if the seller will allow it — most reputable breakers do.

Charity shop furniture analogy is spot on though. Works brilliant until it doesn't.

Yeah, had similar luck with mine on the boat. Grabbed four 250W Canadas off a bloke in Bristol who was upgrading — cost me about £320 total. Been two years, no issues yet, though they're definitely not shifting the same wattage as new ones would.

The thing nobody mentions is the hassle factor. You can't see degradation in real time, and tracing dodgy panels through a Victron setup is annoying. I'd say secondhand works if:

• You've got space to over-spec (I run 1.2kW for what I actually need)
• You can test them before buying
• You're comfortable with a possible 15-20% output loss

@DriftWizard's right about the rabbit hole. Saved maybe £400 total, but spent fifteen hours checking specs and arranging pickups. New Fogstars or budget Renogys have warranties that take the stress out, which counts for something.

If you've already got a decent monitoring setup and don't mind playing detective, secondhand panels are fine. If you're new to this, the peace of mind from new

Grabbed a bundle of knackered-looking 250W Canadas myself for the static caravan last year — seller swore blind they were "just dusty" and he wasn't wrong. Three years in and they're still shifting power at roughly 85% of their rated output, which frankly beats paying full whack for new ones when you're just topping up a leisure battery setup.

The trick is checking the backsheet for micro-cracks and actually measuring their performance before handing over cash. A decent multimeter under direct sun takes five minutes. I've also seen folk on here get properly stung buying panels that looked cosmetically fine but had internal lamination issues.

For emergency backup or supplementing an existing array? Brilliant. For your primary power source where you need reliability? Maybe stretch for at least refurbished stock with a warranty. Those Victron or Fogstar combos aren't cheap, but they're not forgiving of dodgy panel strings either.

Been pondering this myself given my boat setup. The thing that's caught me out is you don't really know the history, do you? Panels that look mint might've been sat in a damp garage for five years.

I'd say it depends on your situation. If you've got space for a few extras to compensate for degradation, secondhand makes sense cost-wise. But if you're tight on roof/deck space like me, you want panels operating at closer to spec.

What I've found useful is asking the seller directly about installation date and any performance data. Most folk won't have it, but occasionally you get someone upgrading because they kept proper records.

The bigger risk I reckon is with really old stock — pre-2010s panels can have dodgy bypass diodes and aren't worth the hassle. That Victron MPPT'll work harder than it needs to and you lose efficiency gains.

Has anyone here actually had panels properly tested before buying? Seems mad to spend £80 on a panel without knowing if it's actually outputting the claimed watts. Might be worth the testing cost on larger hauls.

Spot on about the history, @EwanCole58. I picked up a mixed batch of older Renogy panels for my boat two years back and one of them developed a micro-crack inside the laminate within months — completely invisible from the outside. Performance just tanked on that string.

What I've learned is asking the right questions before buying makes all the difference. Where were they stored? Any water ingress signs? Have they been tested recently? I now use a basic multimeter to check open circuit voltage against the nameplate specs — gives you a rough idea if they're genuinely degraded or just dusty.

The real gamble isn't the panels themselves lasting (they're pretty hardy), it's whether you're getting someone else's problem. Delamination, hidden microcracks, or salt spray damage if they've been coastal.

That said, if you're buying from someone upgrading their own system (like @ExChippie94 mentioned), that's lower risk. They've got skin in the game with their reputation. eBay bundles from randoms? Proper lottery.

Probably worth factoring in testing costs or having a sparky inspect

Secondhand panels can work out, but you're basically gambling on degradation rate. Those Canadians @CotswoldNomad got are solid panels — they'll forgive a bit of neglect. The real risk is you won't know if you've picked up stock that's already taken a battering.

What I'd actually check: look for physical damage (micro-cracks are silent killers), and if the seller's got any paperwork, grab the date codes. A 2015 panel that's been in a dusty barn versus one that was properly maintained are worlds apart. You could get 25 years out of one and hit 15% degradation on the other within five.

For garden office setups especially, I'd rather spend the extra on used-but-tested stock from reputable second-hand solar firms than random eBay bundles. Places like Solarcentre occasionally shift ex-demo Victron or Fogstar gear that comes with some warranty cover.

Budget angle: if you're chasing bargains, honestly better to buy one or two good used panels than a dodgy bundle. Quality over quantity.

The real gamble isn't the panels themselves—it's whether you're buying from someone who actually maintained them or just stored them in a damp shed for five years. Those Canadians @CotswoldNomad got are solid units; they don't mind a bit of age if they've been kept dry.

What folks don't mention: a cheap multimeter and twenty minutes testing open-circuit voltage tells you more than the seller's story ever will. I've got a mixed array with some 2015 Renogy panels still pulling 90% rated output, sat next to newer ones that started degrading immediately because the previous owner left them facing west in full sun with no airflow.

The economics work if you're patient enough to test before buying and ruthless about walking away. But if you're retrofitting to an existing Victron setup, factor in new DC cabling and breakers—pound for pound that's where secondhand really saves you versus the panels themselves.

Skip eBay job lots though. Single-panel sales from people downsizing their setups? That's where the bargains actually are.

The real question is whether you've got time to argue with eBay sellers when they stop working in six months. I've got three Canadians from 2019 still doing their thing on the motorhome, but I also got absolutely mugged on a pair of Renogys that turned out to have been stored in someone's leaky garden shed.

Dead giveaway is asking for photos showing actual output under load, not just glamour shots. And check if there's any documentation of what they've been through—genuinely maintained panels age gracefully, neglected ones just age bitterly.

The maths works if you're lucky. The physics works if they've been treated decently. Getting both is rarer than finding a hookup site with proper 16A supply. Your contingency fund should be as big as your savings, basically.

The degradation angle @QuietTrekker mentions is spot on, but honestly the bigger issue is knowing the installation history. I picked up a batch of Canadian 300W panels three years back—similar price to @CotswoldNomad—and they're still performing near spec. The difference? I got them from a commercial decommissioning, so I had proper paperwork on how they'd been installed and maintained.

With eBay buys, you're essentially flying blind. Some sellers are legit—end-of-lease commercial systems, genuine upgrades—but others are shifting panels that've been sat in a damp garage for five years. No way to know without specialist testing equipment.

If you're handy with a multimeter and can physically inspect them before purchase, secondhand can work out. Otherwise, the £50-100 you save per panel vs new doesn't seem worth the hassle if one drops significantly below rated output. Especially paired with a proper Victron MPPT that'll show you exactly what you're getting—you'll spot a dud pretty quickly.

Location matters too. Coastal panels get hammered by salt; panels from

I've been down this road with my static caravan setup, and I reckon the key is what you're using them for. I picked up four 250W panels from a dismantled commercial array for about £60 each—the seller had full documentation, which made all the difference.

For my emergency backup system, that degradation @QuietTrekker mentioned barely registers. I'm not expecting peak performance; I just need to trickle-charge the batteries through winter. But if you're sizing a system expecting rated output, secondhand is a risky game.

The real tell is whether you can actually verify the installation history. Those Canadians @CotswoldNomad grabbed sound decent, but I wouldn't trust unmarked panels or anything that's been sat in a garage for years. Moisture gets in, invisible damage builds up.

My advice: secondhand works brilliantly if you're either buying from someone you can quiz properly, or you're factoring in 15-20% efficiency loss from the start. Pair them with a decent MPPT (I'm running Victron gear) and you can squeeze every watt out

The degradation curve is the real wildcard here. Those Canadians @CotswoldNomad picked up are solid panels, but you're essentially gambling on their history. I've got a mix in my garden office setup—three new 400W Renogys and two older 250W monocrystallines I sourced from a dismantled commercial array.

The secondhand ones test at about 78% of rated output now, which actually aligns with what you'd expect after 8-10 years of use. They're still generating, mind you, but the problem @CableTieWarrior raises about installation history is crucial. Were they in a salt-air environment? Mounted on a south-facing caravan that spent years in direct sun without proper ventilation? That degrades them faster than normal.

My approach: secondhand makes sense if you can verify the source and accept lower output. Pair them with a decent MPPT controller (Victron or Fogstar) that can squeeze efficiency out of degraded panels. Don't go secondhand on the electrics though—dodgy controllers and chargers aren't worth saving a hundred