Electronic scrap processors are developing strategies for more and more photovoltaic modules to enter the market. | Hill120 / Shutterstock
In some respects, solar panels face the same recycling challenges as old TVs. Their correct recycling costs are very high, their commodity value is limited, and they contain hazardous metals. At the same time, relatively few downstream processors recycle them, and the market opposes reuse.
“Solar panels are almost the new CRT,” said AJ Orben, vice president of We Recycle Solar in Arizona, referring to the cathode ray tube, which contains lead glass and is used in old, bulky TVs.
Interviews with experts in the electronics and solar panel recycling industry revealed the challenges faced by the industry in photovoltaic (PV) modules. Photovoltaic (PV) modules may be stored, dumped, abandoned or illegally landfilled, just like CRTs in many cases The next is the same.
Partly to prevent potential mismanagement of certified recycling facilities, the non-profit organization Sustainable Electronics Recycling International (SERI) is working to add solar panels to its R2 e-waste certification standard. Nearly 1,000 electronic product recycling facilities worldwide have passed the R2 standard certification.
At the same time, more and more solar panels will continue to enter the scrapped stage. However, with the processing complexity—and the expected additional regulations—is a business opportunity.
“This is just the tip of the iceberg,” said John Shegerian, co-founder and executive chairman of National Electronic Processor ERI, referring to the number of panels his company currently recycles, about a semi-truck trailer a week. “This is just to warm up for the game.”
According to data from the US Department of Energy, about 95% of the panels currently sold are crystalline silicon, and the photovoltaic cells are made of silicon semiconductors. Solar panels are designed to withstand these elements for decades and consist of interconnected photovoltaic cells encapsulated in plastic and sandwiched between glass and a back sheet. A typical panel has a metal frame (usually aluminum) and external copper wires.
In an article on resource recovery last year, Melissa Ann Schmid of EnergyBin, a solar energy equipment exchange, explained that crystalline silicon panels are mainly made of glass, but also contain plastic, aluminum, silicon, and copper, as well as trace amounts of silver, tin, and lead. .
Recycling companies can easily separate the aluminum frame and the external copper wire for recycling. However, because photovoltaic cells are encapsulated in an ethylene vinyl acetate (EVA) plastic layer and bonded to glass, additional processes are required to recover silver, copper, or high-purity silicon in silicon wafers.
We Recycle Solar owns a large solar panel recycling plant in Yuma, Arizona. The plant is located in a city on the California border and a smaller plant in New York City. We Recycle Solar was launched five years ago and recycles tens of thousands of solar panels every week, using materials from homes, businesses and solar farms.
Orben said the company is the largest recycler of solar panels in the United States, although he pointed out that only a few companies recycle all or almost all of the solar panel materials.
We Recycle Solar removes the aluminum frame and wires and shreds the panels. He said that the crushed mixture undergoes secondary chemical treatment, electrolysis and other processes to separate metal, silicon and glass, and then shipped to downstream processors.
ERI is located in Fresno, California and processes solar panels for Redwood Materials, a start-up company located in Carson, Nevada, that aims to recover valuable metals from batteries. In April, ERI announced a partnership through which the processor sends all recycled batteries and shredded solar panel waste to Redwood Materials. According to the ERI press release, as part of the agreement, Redwood invested a significant amount of money in ERI.
Shegerian said that ERI has been working on the research and development of solar panel recycling for about three years. After removing the aluminum frame, ERI reduced the size of the panel in the reconstructed shredder. The key step of the process is to shred and separate the glass from the metal-containing material while avoiding unnecessary emissions.
The resulting metal-containing material balls are then shipped to Redwood, where the company uses its technology to separate metals such as copper, silver and lead.
Another e-waste company that processes solar panels is Echo Environmental, which operates a 166,000 square foot recycling and reuse facility in Carrollton, Texas, near Dallas.
Tommy McGuire, president of Echo Environmental, said that Echo workers receive more than 1 million pounds of solar panels from manufacturers and other companies each year. They first remove the aluminum frame and cut the wires for recycling.
Echo then shreds the module, and then uses a milling process to separate a portion of clean glass, which is sold for fiberglass insulation and reflective paint. The remaining metal-containing materials are mixed into shredded circuit boards from electronic products and then shipped to smelting.
Complicating the scrap equation is the fact that certain types of panels are considered dangerous due to their concentration of toxic metals. The South Carolina Department of Health and Environmental Control has produced a fact sheet that lists the different types that may be considered hazardous and points out that harmless panels can be disposed of in a municipal solid waste landfill.
Among the types that require special treatment, thin-film batteries are rarer than crystalline silicon panels. First Solar is a solar panel manufacturer and has been implementing a recycling program since 2005 to produce cadmium telluride thin-film solar cell modules. According to First Solar, the recycling process includes shredding and grinding in a hammer mill. After that, the EVA laminate is separated from the clean glass. In addition, third-party companies perform metal precipitation processes to recover cadmium and tellurium.
Echo’s McGuire said that due to hazardous metals and additional disposal requirements, Echo recommends that its customers send cadmium-containing thin-film batteries directly to First Solar’s recycling facility in Ohio.
He pointed out that in general, Echo’s tests showed that other panels are not hazardous waste. But they still need to be handled carefully.
“Your typical photovoltaic modules will not have a lot of hazardous effects, but similar to electronic products, we certainly don’t want them to fill our landfills,” McGuire said.
Orben of We Recycle Solar said his company’s tests showed that under the Federal Resource Conservation and Recycling Act (RCRA), more than two-thirds of the panels are considered hazardous waste due to their lead or silver concentration. According to California standards, approximately 90% of the same panels are considered dangerous because even if they do not exceed the acceptable lead or silver content, they exceed the state limit for copper or zinc.
According to the U.S. Environmental Protection Agency, our Yuma plant that recycles solar energy has a hazardous waste license, which states that corrosive waste, cadmium, lead, and silver are processed there.
In addition to the consideration of hazardous materials, recycling solar panels also faces challenges in terms of economic feasibility.
According to a March 2021 report from the National Renewable Energy Laboratory (NREL) and the Electric Power Research Institute, “Current technologies, infrastructure and processes related to recycling photovoltaic modules are not optimized for cost-effective recycling of high-value materials. “As a result, recycling costs are often offset by cheaper and more accessible disposal methods.”
Orben said that the processing cost of each panel of We Recycle Solar is as high as US$25, and it is worth US$2 to US$4 from aluminum, copper, lead, glass, silver and silicon. He said that OEMs are already lightweighting and using lower-value metals in a new generation of more efficient products, which is good news from the perspective of manufacturers and consumers, but not for recyclers.
At the same time, Orben does not expect processing costs to drop significantly in the future due to economies of scale. Many costs will still be related to labor, and it is expected that labor will only become more expensive.
He pointed out that when the alternative is hazardous waste treatment, there are still economic incentives for waste generators to pay for recycling panels, but when cheaper municipal solid waste landfills are available, this effect will disappear.
In addition, Orben pointed out that not all collectors understand the economics of correct handling of materials, which created cost pressures from the start.
We Recycle Solar often receives calls from transfer stations, landfills, and other recyclers who accept solar panels for free or at a low price (for example, 10 cents per pound) because they think they contain a lot of valuable material.
McGuire of Echo Environmental added that the commercial value of solar panels is mainly reflected in the aluminum frame, and wire and clean glass products also generate a certain amount of income.
Echo’s process of mixing shredded photovoltaic cell material with shredded circuit board waste shipped to a smelter reduces the value of the circuit board mix by a few cents per pound, but this practice also keeps the material away from landfills and allows recycling Metals also offset the demand for fluxes from smelters, he said.
ERI’s Shegerian pointed out that for now, his company’s Fresno plant is ERI’s only plant that processes solar panels. But ERI’s other facilities across the country receive calls about solar panel recycling every day.
“The opportunities are huge, but to do it the right way will cost a lot of money,” Shegerian said.
Solar panels are designed to generate electricity for decades, so reselling used panels may be the best economic and environmentally friendly option, and this exchange does happen.
At the same time, processors said that certain market and tax policy forces are also opposed to reuse.
McGuire said Echo has the ability to test the energy output of used panels so that they can be resold. He said that this is effective for higher-value modules, and pointed out that there are international markets for second-hand modules as well as one-off domestic projects.
But he pointed out that panels that have not passed the manufacturer’s quality control inspection cannot be resold. McGuire said that when contractors perform disassembly and aggregation and ship solar panels to Echo, what usually arrives is that the different types of panels do not match, making it difficult to maintain a consistent inventory.
In addition, the pace of panel innovation hinders resale, because the price of new panels declines as efficiency increases. According to data from the U.S. Energy Information Administration, the average value of photovoltaic modules shipped in 2019 (the most recent year for which data is available) was 41 cents per watt of peak power generation. Ten years ago, the average was US$2.79 per peak watt.
We recycle solar energy and do resell solar equipment. But Orben also compares this problem to a problem faced by certain areas of the electronics market. “Owning a panel that was still in production 15 years ago is like owning today’s Pentium 3,” Orben said.
What further hinders the secondary market is the tax policy of the United States. McGuire pointed out that the federal government provides tax credits for homeowners who install new photovoltaic systems-by 2021, the credit will be 26% of the cost of the system.
“It’s really an unbalanced competitive environment, because you can’t get tax credits on second-hand modules,” McGuire said.
According to data from the US Energy Information Administration, shipments of new panels have increased substantially in the past 15 years. In 2019, the shipments of photovoltaic modules were sufficient to generate more than 16 million kilowatts of peak power, an increase of nearly 14 times from the shipments ten years ago.
Due to the performance improvements and cost reductions of the new panels, many of them will be decommissioned before the end of their useful life (ERI’s Shegerian said that because the return on investment is so compelling, power producers may replace them in five years or less ).
A report by the International Renewable Energy Agency (IRENA) and the International Energy Agency’s Photovoltaic Power Generation System Program (IEA-PVPS) estimates that by 2050, the global cumulative amount of photovoltaic panel waste will reach 60-78 million tons. Above about 43,500-250,000 tons in 2016.
The report calls for the adoption of measures such as photovoltaic specific waste regulations. Some of it has already happened. For example, Europe has passed laws that force solar panel manufacturers to fund the collection and recycling of their products.
In 2017, Washington State became the first state to pass a bill that established an Extended Producer Responsibility (EPR) program for solar panels. Starting in July 2023, the law will require manufacturers to provide funds for the collection and recycling of panels.