Recycling Opportunities for End-of-Life Solar Panels
Global solar panel use is expected to grow rapidly in the coming decade. Solar experts are concerned that recycling opportunities for PVs are not keeping up.
With help from public and private sector funding, the global solar power capacity is expected to surge in the coming years. In 2021, solar photovoltaic (PV) generation experienced a remarkable growth of 179 TWh (a 22 percent annual increase), surpassing a global capacity of 1,000 TWh. This capacity growth is expected to increase at a similar rate each year through 2030.
Solar panels. Image used courtesy of Pixabay
China accounted for 38 percent of 2021 solar PV generation growth, followed by the U.S. at 17 percent and the European Union at 10 percent.
However, experts caution that this remarkable growth in low-carbon power presents a significant challenge. Over 90 percent of PV panels are constructed with crystalline silicon and have an approximate lifespan of 30 years. Projections indicate that by 2030, around 8 million metric tons of these panels will have reached the end of their operational lives, and this figure is estimated to escalate to 80 million tons by 2050.
Unfortunately, the current recycling technologies for these panels are inefficient and seldom utilized, and most decommissioned PV panels end up in landfills. Solar experts from Australia are hoping to find ways to mitigate this issue.
By 2030, Australia is expected to generate 145,000 tons of PV panel waste, while the United States may accumulate between 0.17 and 1 million tons. This poses an immense threat as PV panels contain hazardous substances like lead, which can result in environmental pollution when disposed of in landfills.
Solar PV power generation in the Net Zero Energy (NZE) Scenario, 2010-2030. Image used courtesy of the International Energy Agency
These panels also contain valuable materials that could be recycled and repurposed for producing new solar cells, but currently, these resources are predominantly wasted.
In the United States, there are currently no federal regulations to enforce the recycling of PV panels.
According to the U.S. National Renewable Energy Laboratory (NREL), less than 10 percent of decommissioned panels in the country are recycled. Even in the European Union, where PV recycling is mandated by legislation, many waste facilities focus on recovering bulk materials such as aluminum frames and glass covers, which comprise more than 80 percent of the panel's mass.
The remaining portion, containing valuable elements like silver, copper, and silicon, which account for two-thirds of the material's monetary value, is often incinerated instead of properly recycled.
Barriers to Recycling
In a survey of U.S. Policies and Initiatives, the NREL identified several barriers to PV panel recycling opportunities in the US. These include data gaps, inadequate recycling technology and infrastructure, and regulatory uncertainties.
There is a limit to research and publicly available information regarding the value and markets for recovered PV materials, the volume and composition of near-term end-of-life (EoL) PV modules, the development of PV module recycling technology, infrastructure needs, and the overall costs associated with PV module recycling.
The current recycling technology, infrastructure, and processes for PV modules are not optimized for the cost-effective recovery of high-value materials, making the cost of recycling less desirable than the cheaper and more accessible disposal options.
The NREL also found a need for incentives for recycling, similar to solid waste disposal.
Management and disposal practices for PV modules in Australia differ across states and territories. Only Victoria has implemented an official ban on solar panels being disposed of in landfills. Residents in Victoria must take their solar panels to designated e-waste drop-off points for recycling.
A new recycling expansion program is being proposed in Queensland, which aims to prohibit the dumping of solar panels in landfills within the next ten years. This initiative signifies a growing recognition of the importance of proper disposal and recycling of PV modules to minimize environmental impact and promote sustainable practices.
Unfortunately, the cost for recycling comes to $10-$20 per panel to recycle, not including any fees for transport or removal. Disposing of ten panels from your roof will cost at least $200 for proper recycling disposal.
Benefits of Recycling
Despite the limitations and barriers to recycling end-of-life or decommissioned solar panels, finding ways to increase recycling opportunities is important for supporting a circular economy and the ongoing sustainability of solar energy.
Around 95% of the materials utilized in producing a solar panel can be recycled, with the highest-value components being silicon, aluminum frames, and silver, primarily found in the module's front contacts.
Commercial module recycling processes for solar PV panels. Image used courtesy of the Office of Energy Efficiency and Renewable Energy
In Australia, the prevalent method for recycling panels involves subjecting them to a standardized shredding machine, which breaks them down into smaller fragments. These fragments are then repurposed through down-cycling processes to add to other products such as construction bricks, concrete additives, or roadbase materials.
Repurposing Solar Panels
A notable trend is emerging among homeowners who invested early in solar panels. Many are opting to replace their initially expensive but smaller systems before the end of their expected lifetime, purchasing newer, more affordable systems that offer improved features and qualities.
With increased testing to ensure these older but still working panels meet electrical safety standards, their reuse has a large potential. Repurposed solar panels can find new uses for whole or partially-functional panels, extending their lifespan and reducing waste.
Repurposing options include off-grid installations to power remote locations, cabins, or outdoor lighting, community projects to provide renewable energy to underserved communities, and opportunities to promote solar energy awareness and understanding.
To address the ongoing issue of end-of-life PV disposal, it is crucial to establish global incentives and policies, regardless of the chosen recycling path, supported by manufacturers, policymakers, researchers, and the solar industry.
This proactive approach ensures that the management and disposal of PV panels are effectively addressed globally, acknowledging this challenge's persistent nature.
Countries like Germany and the Netherlands, early adopters of small-scale rooftop PV systems, demonstrate a sense of urgency in pursuing viable technologies to recycle aging PV panels as they approach their end-of-life phase.
In Europe, separation technologies prototypes have been developed, and several pilot lines are in place to test their feasibility.
In Australia, the sense of urgency is not as prevalent, as the anticipated waste issue resulting from end-of-life PV modules has yet to materialize. Consequently, local companies have less incentive to invest in recycling technology.
However, it is crucial to acknowledge that there will come a time when landfills will be insufficient to accommodate PV modules, and resources to manufacture new panels will be scarce. Hence, finding a sustainable solution for recycling them is imperative.