What is a pallet of nine-year-old modules actually worth once it has come off the racking?
Very few people on a decommissioning crew can answer that question on the day it is asked, and the asset owner usually asks it while the torque wrenches are still out. The honest answer is that the value depends on about six variables, only two of which were typically measured before the job started.
Meanwhile, the volume of retired hardware keeps increasing. IRENA and IEA-PVPS, in their joint report on end-of-life management for solar photovoltaic panels, projected a global stock of approximately 78 million tonnes of raw materials and other valuable components tied up in decommissioned panels by 2050. A meaningful share of that material is not scrap. It is working equipment that somebody will pay money for, provided it is handled well enough to still be working when it arrives with them.
What “Used” Actually Means Once the Array Is Down
There are four terms that get used more or less interchangeably in conversation, and they are not interchangeable on a purchase order.
Surplus panels are new modules that were never energized, which usually means overordered stock, a project that was value engineered partway through, or a cancelled expansion. They normally still have their factory packaging and an intact manufacturer warranty, so they are the easiest units to sell, and they command the highest prices.
Used panels are modules that were installed, produced power for some period, and then came down in working condition. Age matters somewhat less here than most people expect, while condition and documentation matter considerably more.
Decommissioned panels are a subset of used panels, specifically modules removed as part of a planned site retirement or a repower. They generally come down in volume and with at least some project records attached. This is the category where the commercial secondary market actually operates.
End-of-life panels will not produce usefully again, because of cracked glass, delamination, severe backsheet degradation, burned interconnects, or water ingress at the junction box. These units go to material recovery rather than resale, so they sit on the cost side of a decommissioning budget.
A single array will typically produce all four categories at once, and sorting them before you contact anybody is worth real money, because a mixed and unsorted lot tends to get priced at the level of its worst visible unit.
The Three Places a Pallet Can Go
Every resale route for retired modules falls into one of three channels, and which one is appropriate depends almost entirely on the quantity you are moving.
Open Marketplaces and Auction Platforms
These list your inventory in front of a broad pool of buyers. You keep control of the pricing, and in exchange you carry the work yourself, which includes photographing lots, answering technical questions from people you do not know, arranging freight, and staying compliant with whatever your state requires around handling and transport. For a full truckload, that turns into a part-time job for somebody on your team who already has a full-time one.
Direct Buyers
Direct buyers purchase the lot outright. These are companies that operate their own testing and refurbishment capacity, or that recycle whatever they cannot resell, and they buy for their own inventory rather than for a specific end customer. You give up some pricing power, and in return you get speed, a single point of contact, and access to somebody else’s logistics department.
Brokers
Brokers sit between the two. A broker does not take title, but finds a buyer, takes a margin, and leaves the physical handling either to you or to a third-party freight provider. A broker can genuinely earn that margin on a specialized lot, for example, an obsolete thin-film product with a small but real installed base that still needs replacement modules. On a straightforward lot of common crystalline modules, a broker mostly adds a step and a fee.
The failure mode I have seen most often is a site attempting to run all three channels at once. The lot gets listed publicly, quoted to two direct buyers, and shopped around by a broker, and within a fortnight most people in what is a fairly small industry have concluded that the inventory is stale.
What Decides Whether a Module Is Worth Money or Worth Recycling
Resale value on used modules is set by four factors, roughly in this order of importance: physical condition, verified output, wattage class, and the quantity of matching units in the lot.
Physical Condition
Physical condition gets assessed visually first, because a visual inspection is the cheapest screen available and it eliminates the largest number of units. You are looking at:
- The glass, for cracks and chips, particularly at the corners, where handling damage concentrates
- The encapsulant, for browning or delamination
- The backsheet, for cracking and chalking
- The inside of the junction box, for corrosion
- The leads, for damaged insulation
A US Department of Energy article on the salvage value of used photovoltaics, describing a salvage operation involving approximately 144 modules, reported that about 15 percent of the modules were discarded for glass breakage, delamination, serious browning of the encapsulant, burn marks on the interconnections, or damaged backsheets. If you are pricing out a decommissioning, assume a meaningful minority of your modules will not be sellable at all, regardless of how the array was performing the day the inverter was shut down.
Verified Output
Verified output is the second screen. The industry standard method is a flash test, which places the module under a calibrated light source and produces a current-voltage curve, giving you measured peak watts against the nameplate rating. Out on site, a max power point current and voltage meter, corrected for cell temperature and measured irradiance, will get you close enough to make a grading decision. A buyer with a laboratory-grade flash tester will re-verify on receipt anyway, and will price against their own measurements rather than yours.
Measured output rarely surprises anyone who has read the research, because crystalline silicon degrades fairly predictably. The NREL compendium of photovoltaic degradation rates, which aggregated more than 11,000 reported degradation rates drawn from almost 200 studies, put the median for crystalline silicon at roughly 0.5 to 0.6 percent per year, with a mean closer to 0.8 to 0.9 percent. Applied to a twelve-year-old 320-watt module, that implies an output near 300 watts, which is precisely the sort of unit that has a healthy second life in an off-grid, agricultural, or developing-market application.
Wattage Class and Matching Quantity
Wattage class and matching quantity are the variables sellers underrate, because buyers want electrically matched strings. Two hundred identical 400-watt modules from a single manufacturing run are worth more per unit than the same two hundred split across four models and three wattage classes, since the buyer can sell the first lot as a system and has to sell the second as parts.
The Paperwork That Moves the Price
Documentation is the cheapest available way to raise your realized price, and it is also, in my experience, almost always the thing that is missing. What you want ready:
- The datasheet for each model
- The original commissioning records, where they still exist
- Any string-level production data from the monitoring platform
- The serial number ranges, broken out by pallet
Serial numbers matter more than most sellers assume, because they allow a buyer to confirm the manufacturing date and, occasionally, to check a model against a known defect campaign.
Warranty Transferability
Warranty transferability is something to check rather than assume. Manufacturer product and performance warranties on commercial modules are frequently non-transferable, or transferable only once, or voided the moment the module leaves its original site or is reinstalled by a party who is not a certified installer. A number of the original manufacturers no longer exist, which settles the question less satisfyingly. Read the warranty document rather than the marketing sheet and tell prospective buyers what you found, because a buyer who discovers a dead warranty after quoting will come back and re-quote lower.
Regulatory Requirements
Then there is the regulatory side, which is where sellers most often get themselves into difficulty. Under RCRA, the US Environmental Protection Agency treats a panel as solid waste once it reaches the end of its usable life or is otherwise discarded, and heavy metals including lead and cadmium may be leachable at concentrations high enough to fail the toxicity characteristic leaching procedure (TCLP).
The EPA has been explicit that results vary by product, with some panels passing the TCLP and others failing, and the agency has been developing a proposed rule that would bring solar panels into the universal waste regulations. Panels you genuinely resell for reuse are commodities, whereas panels you discard are waste. The hazardous waste determination sits with you as the generator, and getting it wrong creates a compliance problem that outlives the salvage revenue by several years.
Why Volume Changes the Arithmetic Completely
The part that tends to get left out of articles on this subject is that freight and handling routinely cost more than the modules themselves are worth.
A standard 72-cell module weighs somewhere in the region of 22 kilograms and is mostly glass. Palletized properly, meaning on edge, with corner protection and edge board, in the vertical orientation the manufacturer specified, you will fit a few hundred modules on a truck. Palletized badly, laid flat and stacked, what arrives is a pallet of broken glass and a credit note. I have watched a crew stack modules face down on a warehouse floor for three days because there was nowhere else to put them, and roughly a fifth of that lot was unsellable by the time it shipped.
On a per-module basis, the fixed costs do not scale down, which is why warehouse and freight operations are where most of the margin is won or lost. A pickup, a freight booking, a dock appointment, a receiving inspection, and a testing pass all cost approximately the same whether the pallet holds 40 modules or 400. That is the reason nearly every serious commercial buyer sets a volume floor, and it is also why owners of small arrays get politely redirected toward online marketplaces no matter which company they call.
Above that floor, the arithmetic reverses, and the specialist buyers become the sensible first call for anybody who needs to sell used solar panels off a commercial rooftop or a utility-scale field rather than off a house. Solar Recycling is one of the companies working at that end of the market, buying used and excess-new panels, inverters, and battery storage from EPC contractors, O&M providers, and solar farms with a typical minimum of around 100 panels. It runs the transaction as a three-step commercial process: submitting details and photos, receiving an estimate that covers scope and material recovery potential, and then dispatching the pallets.
The detail worth borrowing from that model, whichever buyer you end up using, is what happens to the modules once they arrive: technicians inspect, clean, test and repair each unit, and the inspection and test results for each panel are recorded and made available to the customer on request. The company publishes a resale range of $0.05 to $0.60 per watt for used modules against $0.70 to $1.50 per watt for new ones, and approximately $20 to $50 per panel plus shipping to recycle whatever cannot be recovered as working equipment.
Those two figures, resale value per watt and recycling cost per panel, are the ones to model against each other before you commit to a channel. A decommissioning that yields 70 percent resale-grade inventory is a revenue event, while one that yields 30 percent is a disposal budget with a modest offset attached, and the difference is usually decided by handling rather than by the age of the array.
What Happens to the Fraction That Can’t Be Resold
It is worth understanding what happens to the fraction that cannot be resold, because that is the half of the transaction sellers rarely ask about. At a full-service operator, the recycling line runs to a fixed sequence:
- Discovery and qualification of what came in
- An estimate of scope and recovery potential
- Inbound logistics
- Mechanical reprocessing to separate the materials
- Certification
The materials on the recovery list are glass, aluminium, silicon, silver, and copper, and the job closes with a report of what was recovered plus a certificate confirming compliant processing. If a buyer cannot describe that sequence to you, they are almost certainly brokering your scrap onward to somebody who can.
How to Vet the Company on the Other End
The market for retired modules is not heavily regulated, and the barrier to entry is essentially a website and a phone number. Five questions reliably separate the real operators from the intermediaries.
- Where does the material physically go? A genuine buyer can name the facility, tell you whether it is theirs or a downstream partner’s, and describe what happens to units that fail inspection. A vague answer here is the strongest warning sign available to you.
- What are the certification specifics? A good number of companies in this space describe themselves as certified without naming the certifying body, the certificate number, the scope, or the expiry date. All four are reasonable things to request in writing, and a legitimate certificate holder will send them without friction.
- What documentation closes the job out? For the recycled fraction, you want a certificate of completion, or an equivalent record confirming responsible processing, ideally with recovered material quantities. That document is what you hand to your compliance team, and it is the difference between a defensible file and a paper trail that stops at a pickup receipt.
- Who owns the freight risk, and when does title transfer? Damage in transit on a used-module shipment is common enough that the answer should come back immediately and specifically.
- Will they price the whole lot, including the fraction they won’t resell? A quote covering only the good modules is a quote for the easy part of your project, and the rest comes back to you later as a cost.
Frequently Asked Questions
What is a realistic price per watt for used commercial modules?
It varies more widely than any single published figure suggests. The Department of Energy’s salvage analysis cited resale data showing single crystalline and polycrystalline modules moving at approximately $0.17 to $1.26 per watt over a multi-year period, with amorphous silicon considerably lower at $0.04 to $0.97. In the same analysis, performance-tested modules with their junction boxes intact resold for $30 to $50 each, while bulk modules without junction boxes went for around $20. Treat published ranges as a sanity check on an offer rather than as a market price.
Do manufacturer warranties transfer to the buyer of used panels?
Sometimes, and less often than sellers hope. Many commercial module warranties are tied either to the original purchaser or to the original installation site, and removal from that site can void the performance warranty outright. Some transfer once, with written notice to the manufacturer. Where the original manufacturer has exited the market, the question becomes academic. Check the warranty document for each model in the lot before you make any representation to a buyer.
Can I just send working panels to a landfill?
In most jurisdictions, you can attempt it, and in a growing number of them you cannot. Once a panel has been discarded, it becomes solid waste under RCRA, and if it fails toxicity characteristic leaching testing, it is hazardous waste, with the determination falling on the generator. Several states have gone further with rules of their own. Setting aside the legal exposure, landfilling a module that would have sold is a fairly direct waste of an asset.
How long does it take to sell a decommissioned array?
A direct sale to a specialist buyer typically runs a few weeks from first contact through to pickup, assuming the documentation is ready and the lot has been sorted. Marketplace and broker routes take longer and are harder to predict, because you are waiting on a matching buyer to appear rather than working against somebody’s existing inventory plan. The biggest schedule risk is usually the discovery, at quote stage, that nobody photographed or catalogued the array before it was disassembled.
Where This Market Is Heading
The secondary market for photovoltaic modules is maturing toward graded, tested and documented inventory sold in matched lots, and away from pallets of mixed hardware sold over a phone call. The implication for anybody planning a decommissioning is that most of the value gets determined before the sale rather than during it.
The inspection you carry out while the modules are still on the racking, the way they are palletized, and the records you keep are what decide whether you end up selling equipment or disposing of waste.
Key Takeaways
- Sort before you sell. Surplus, used, decommissioned, and end-of-life modules are four different products, and an unsorted lot gets priced at the level of its worst visible unit.
- Budget for a failure rate. A Department of Energy salvage analysis found roughly 15 percent of modules discarded at inspection for breakage, delamination, browning, burn marks, or backsheet damage.
- A buyer prices against measured output, not nameplate. NREL’s compendium puts median crystalline silicon degradation near 0.5 to 0.6 percent per year across more than 11,000 reported rates.
- Matched lots sell better than mixed lots, and documentation raises the price on both. Datasheets, serial ranges, commissioning records, production data, and an honest read of the warranty terms all move a quote upward.
- Volume decides the channel, and handling decides the resale fraction. Modules stacked flat instead of on edge arrive as glass, and the gap between a 70 percent and a 30 percent yield is usually logistics rather than age.
- The waste determination stays with you. Discarded panels are solid waste under RCRA, some fail TCLP testing, and the generator carries that responsibility.
