Solar panels are leading the clean energy revolution, but recycling them isn’t easy
Just as one truck leaves, another arrives.
Almost every day, the Anthony Vippond solar recycling plant in North Melbourne receives dozens of used solar panels.
In the car park, multiple tilting towers of the devices, linked by moorings, occupy the spaces.
Right now, many of them are coming from schools as the state government upgrades or replaces around 500 solar panel systems.
Others come from businesses, homes or solar farms in rural Victoria.
Some have big holes in the middle, some are smashed, but most have no damage at all and have been scrapped because they aren’t as efficient as they used to be.
All those used panels have to go somewhere, and it can’t be a landfill; Victoria, South Australia and the ACT have banned solar panels from ending up in landfill: they must be taken to e-waste drop-off points for recycling.
It was a move made to prevent the heavy metals from the panels from seeping into the earth and, with an estimated 26,000 tonnes of solar panels expected to go to waste each year in Victoria from 2035, to force the industry to innovate.
Solar panels are not made to be disassembled
John Polhill of Sustainability Victoria says it’s a “unique experience” to be able to anticipate a waste stream before it arrives.
But recycling solar panels is not easy.
“They’re laminated, they’re glued, they’re glued,” says Polhill.
To be reused, solar panels must be broken down so that each component, including glass, aluminum, copper, plastic, and silicon, can be separated. And that requires a lot of heavy machinery to do it.
Some of those materials can be sold and used in new products.
Several companies in Victoria and South Australia are testing different methods of breaking down solar panels, from using chemicals and heat to dry processes and computerized mechanical systems.
Each says their process is better than the one next door. But everyone has admitted one thing: the margins aren’t big.
A new way to extract nano silicon
Most solar recyclers disassemble and sell the aluminum from the frame, try to extract as much of the valuable metal as possible, and then store the rest.
Polhill says that at the moment “it would be cheaper to landfill it than to salvage it.”
“During the last few years, companies have started to invest in the recovery of other materials, but that is in its infancy and those materials have a very small market,” he says.
But there’s one part of a solar panel that could change that: nanosilicon.
The silicon is inside the black and gray panels that capture sunlight.
And when refined into its purest form, nanosilicon, it can sell for around $64,000 per kilogram. It’s a ubiquitous substance used in everything from mobile phones and concrete to rubber, plastic and computer chips.
Until now it has been difficult to reduce silicon to its nanoparticles without using harmful chemicals such as hydrochloric acid and nitric acid.
But researchers at Deakin University in Geelong say they have discovered a way to do it that is cheap, effective and safe for the environment.
Researchers at the university began investigating their theory in 2019 and have repeatedly tested and revised the process to show that it can work and be scaled up for commercial use.
“Compared to other processes around the world, my process is really environmentally friendly,” says Mokhlesur Rahman, Deakin’s principal investigator.
Making Solar Panel Recycling More Profitable
Dr. Rahman says he’s also discovered a way to combine nanosilicon with graphite to create longer-lasting lithium-ion batteries for use in products like electric cars.
It’s a breakthrough that could make solar panel recycling a much more viable industry.
Back at his recycling plant, Mr. Vippond has been trying to create new products like sleepers and furniture out of solar panel products, but says an easy and cheap way to extract and sell nanosilicon would be a game changer.
“Getting the best solar panel recovery is probably more important than any other product just in relation to that [environmentally conscious] category he comes from,” he says.
“Some of the work that Deakin University and others are doing on their research is pretty incredible.”
But Polhill is skeptical.
“How do we take that research and create a business model? That’s the real nut to figure this out,” he says.
“Solar panel recycling in Australia is in its infancy. So it needs continued investment from both industry and government to support this developing market and also some of the technologies.”
‘It’s going to dwarf all other e-waste’
Chris Sayers has been involved in e-waste recycling for over a decade in Western Australia and started recycling solar panels in Victoria about a year ago.
He says the volume of solar panels entering waste streams in the next decade is “going to be stratospheric.”
“It’s going to dwarf all other e-waste, it’s a great opportunity,” he says.
He agrees that research like the one being done at Deakin University has the potential to improve the industry by teaching recyclers how to extract materials with as little contamination as possible.
“Yes [materials] can be cleanly mined and decontaminated and a solution found to recycle them, ideally locally, then you can maximize your operation,” he says.
“Right now that’s absolutely difficult.”
Sayers says the countries of Europe are “embarrassingly ahead” of Australia in space.
He is one of many in the industry who wants the federal government to implement a product stewardship scheme so that manufacturers shoulder part of the financial burden of panel recycling.
Photovoltaic systems (solar panels) have been on the government’s priority list for product stewardship for about six years. A national scheme is supposed to be operational in June.
A spokesman for the Department for Climate Change, Energy, Environment and Water says the government is working with stakeholders to design a scheme for waste from the solar system.
“Of course, the timing will depend on the regulatory design work currently being done, which is important to get right,” they say.