Even for an industry accustomed to regularly smashing records, 2023’s global solar photovoltaic (PV) installations were eye-popping. According to a new report by SolarPower Europe, the world installed nearly 90 percent more solar PV in 2023 compared to the previous year.
The report also found that the pace of new solar additions means that there will be two terawatts of cumulative global solar PV capacity by the end of 2024—a rapid doubling of the one-terawatt mark reached in 2022. By 2028, the world could add an additional terawatt of solar PV every year.
This trend is good news for the world’s efforts to decarbonize and limit the negative impacts of climate change. But it also underscores the critical importance of establishing and scaling up capacity to collect, repair, refurbish, and recycle used, defective, and damaged solar modules. Indeed, according to the International Renewable Energy Agency (IRENA), annual recycling streams by 2030 will total about 4 percent of the billions of modules installed around the world each year. To get a sense of the scale of recycling that will eventually be necessary, consider that one terawatt of 500-watt modules would equal two billion modules, which means that approximately 80 million modules may need to be recycled annually.
Recycling Advances Follow Accelerating Solar Installations
There is a widespread understanding of the need for proper end-of-life management of large volumes of solar modules. In 2016 and 2017, the International Energy Agency’s (IEA) Photovoltaic Power Systems (PVPS) program conducted a study funded by the National Renewable Energy Laboratory (NREL) and EPRI that reviewed PV recycling technologies in Europe. The review found a small number of recycling technologies, including four commercial glass and metal recyclers that processed solar modules on an infrequent basis, as well as one PV-specific pilot processing facility.
But as anyone who follows solar will know, advances in virtually every aspect of the industry are remarkably speedy, making that snapshot of PV recycling capacity and sophistication out of date today. The recently released IEA PVPS Task 14 report, Advances in Module Recycling—Literature Review and Update to Empirical Life Cycle Inventory Data and Patent Review, provides an updated and comprehensive view of the state and future trajectory of PV module recycling.
One of the traditional barriers to greater PV module recycling capacity and innovation was the simple fact that not enough modules had reached the end of their useful life. While that remains an issue today, it won’t last much longer. This is spurring recyclers to expand existing recycling technologies or pilot new ones.
“There has been a chicken and egg situation where recyclers didn’t necessarily want to invest in a full-scale PV module recycling line because they’re only getting a couple thousand modules a year,” said Cara Libby, an EPRI technical executive and co-author of the recent IEA report. “They’re still trying to figure out which are the optimal processes from a performance, economic, and environmental standpoint, which is why there are still several approaches in pilot scale.”
That lack of scale has also made recycling financially unattractive to those considering end-of-life options for large volumes of solar modules. “One of the challenges is that recycling is expensive today, so many end users are choosing to landfill modules,” said Libby. “In the U.S., there are no federal regulations encouraging people to recycle, so a lot of modules are just going to municipal waste landfills or, in some cases, even hazardous waste landfills because they may still be cheaper than recycling.”
One of the ways to make recycling more financially attractive is to improve the recovery of high-value materials like silver and silicon, which can contribute to a circular economic model in which materials are repurposed and reused repeatedly. However, seizing the full economic value of recycling requires innovation in the processes and technologies deployed, especially in extracting module materials in as pure a form as possible.
“We know roughly how much of each material is in a module, and we know the market value,” said Libby. “But that depends on how pure the recycled material is. We don’t just care how much material we can recover, but how clean or pure it is because that influences which market applications it can be used for.”
Policymakers and regulators are also keen to improve the quality and scale of PV recycling. In the U.S., the 2021 Bipartisan Infrastructure Law (BIL) set aside $1.5 billion to advance recycling RD&D along with clean hydrogen manufacturing. In 2023, the U.S. Department of Energy’s Solar Energy Technologies Office (DOE SETO) awarded 10 million and announced another $20 million in BIL funding to drive PV technology reuse and recycling. DOE SETO’s action plan aims to make PV recycling cost-competitive with landfill disposal. The European Union’s Waste from Electrical and Electronic Equipment (WEEE) Directive has resulted in rules for collecting and treating end-of-life solar modules.
A Comprehensive Examination of PV Recycling
The fundamental goal of the IEA research was to pinpoint technology advances that make PV module recycling more affordable, technically feasible, and environmentally responsible. To gain an understanding of both the overall state of solar module recycling as well as specific technology improvements, researchers followed a multi-prong approach. As a start, the research team identified 177 recyclers and manufacturers of recycling technology through a combination of online searches, press releases, past studies, and industry connections.
From that initial list of 177, the researchers identified 24 recyclers who were utilizing advanced recycling technology at either a commercial or pilot scale and invited them to complete a questionnaire. Soliciting feedback from recyclers was designed to deepen the researchers’ understanding of the state of technology. Six of the 24 recyclers invited to complete the questionnaire responded with life cycle inventory (LCI) data. Past data collection and recycler responses also allowed the researchers to develop a seventh LCI case. This data collection allowed for a comparative analysis of the rates of material recovery and energy consumption involved with recycling methods and technologies.
In addition, researchers reviewed technical research and patents from universities, research institutions, national research laboratories, and private companies focused on solar module recycling. This surfaced 569 publications about PV recycling and 456 patents related to recycling PV components, processing methods, and recovered materials. Researchers also interviewed recyclers and subject matter experts to better understand their technologies and processes and identify data gaps that need to be addressed.
Steady Advances in Recycling
One indication of the maturation of PV recycling is how many recyclers surveyed in the report focus on treating end-of-life modules. In the 2015-2016 IEA PVPS Task 12 report, only one of the five processes featured was explicitly customized for PV recycling. In this year’s report, however, all seven facilities examined are dedicated to processing solar modules.
A Closer Look at PV Recycling in the U.S.
While the IEA PVPS study focused mainly on Europe-based recyclers, another recent EPRI study examined the state of PV recycling in America. Released in June, Review of End-of-Life Solar Photovoltaic Services in the United States is the result of information provided by 12 end-of-life PV service providers. 11 of the 12 companies completed an online questionnaire, and seven of the firms also participated in a one-hour interview. EPRI partnered with the Colorado School of Mines to conduct the research and publish the study.
A future EPRI Journal story will delve more deeply into the report’s findings. Some initial takeaways include:
- There is sufficient recycling capacity to process the expected volume of crystalline silicon (c-Si) modules reaching end-of-life through 2030. Currently, the throughput for the seven c-Si recyclers that provided data is between 6,500 and 7,400 tons per year, which is equivalent to around 10 to 12 percent of all U.S. c-Si modules reaching end-of-life. Additionally, recyclers providing these services plan to expand capacity to meet higher demand and implement new processes to reduce costs and improve output quality.
- The largest challenge faced by recyclers is recovering high-value components like glass and silicon with sufficient purity to be reused.
- Another substantial barrier to more widescale PV recycling is the low cost of landfilling end-of-life modules.
- Nine recyclers that participated in the study provide in-house PV recycling, while the other three work with third parties. Recycling prices of the companies providing in-house recycling range from $14 to $30 per module compared to between $14 and $35 per module for third-party recyclers.
The report also identified research gaps that need to be filled to affordably and sustainably scale PV recycling in the U.S. They include:
- Demonstrating innovative new technologies that improve the yield and purity of components recycled from modules
- Gain a greater understanding of the environmental performance of advanced recycling techniques
- Informing the regulatory guidance for federal, state, and local governments for the reuse, repair, decommissioning, handling, transport, and storage of used solar modules
Like the IEA PVPS study, the findings of this survey of the U.S. recycling landscape were encouraging. “There has been a lot of progress in PV module recycling over the past few years,” said Libby. “Pilot demonstrations are resulting in high-yield recycling and improvements in extracting pure, high-value materials. If these technologies can scale, the value proposition for recycling will improve.”
EPRI Technical Expert:
Cara Libby
