The government may sound ambiguous about clean energy but it doesn’t want us to trash PV panels or wind blades, says a UniSA researcher working on an end-of-life stewardship program for clean energy gear.

There is no such thing as clean energy, says Peter Majewski. “Wind and solar is definitely not clean; it is causing a lot of problems. Not now, because most of them are still on rooftops, but in 10 years’ time a lot of them are coming down and no-one knows what do with them – then it’s not clean anymore.”

Professor Majewski is leading research at the University of South Australia’s Future Industries Institute to help establish a lifetime stewardship scheme for the PV industry. He’s not down on renewables – he’s all for wind and solar – but he knows a wave of waste is coming across the horizon.

If there are 60 million-or-so solar panels on Australian rooftops today, it can only mean we can expect at least 1.2 million tonnes of material to be recycled somehow or sent to landfill over the next 20 years or so. As for the blades on wind turbines, many thousands of tonnes of composite fibre material will have to be managed.

“The amount of material needed to create the electricity out of solar panels or wind turbines is an issue by itself,” Majewski says. “A staggering amount of material sits in solar panels or wind turbines worldwide. The energy density of these technologies is fairly low.”

The road from here

Product stewardship regulations are needed to support the solar and wind industries. Majewski is looking at the development of legislation for product stewardship or extended producer responsibility legislation to set the regulative background for recycling.

The government is well aware of the potential for significant waste whenever new technology is rapidly adopted, as is the case with solar. If a product is toxic at the end of its life, then the manufacturer should be liable somehow for what it is selling. A recent example is the creation of the Battery Stewardship Council, which covers lead-acid batteries in cars and lithium-ion tech. Televisions and mobile phones are further examples of consumer gear that needs to be disposed of a right way. “Without legislation, it wouldn’t happen,” says Majewski.

UniSA is working with other universities, the Smart Energy Council and the recycling industry to develop a stewardship scheme for solar panels and has submitted a proposal to the Department of Agriculture, Water and the Environment, so that “the things are collected and people are doing the right thing; that all stakeholders know their responsibilities and their duties in order to avoid an unwanted waste stream.”

The surge in solar has set off an alarm. PV panels were listed as a high priority in the 2019 national waste action plan and in 2020 the government announced a product stewardship investment fund and asked for proposals, including solar modules as a priority. Majewski is hoping his proposal will be successful.

The government prefers a voluntary product stewardship scheme where all stakeholders – manufacturers, installers, retailers – agree to measures in order to collect and recycle panels at the end of their lives. “This involves costs, and all stakeholders have to agree to cost-sharing,” he says. There are precedents: paint and car tyres, for instance. In those cases, the purchase price includes the cost of disposal and recycling. Coffee pods and plastic bottles are also in the government’s sights.

Peter Majewski is confident the amount of retired modules coming off rooftops over the next few decades will sustain a viable recycling industry.

Tomorrow’s tabletop

Solar panels are a special problem, Majewski says. They are big and don’t contain a lot of value. “This is a very difficult situation; if you have 20 solar panels on your roof and you want to upgrade, no-one will take them,” he says. In Victoria, solar modules are banned from landfill.

But how do you recycle a solar panel – and is it even worth recycling? Majewski says there isn’t much of value in a panel: the aluminium frame, high-strength glass (not the sort of glass that is easily turned into windows or bottles, although someone is looking into its use as a road base), the silicon in the solar cells, silver or copper-nickel alloy and some plastic. “Overall, there are not a lot of valuable elements in there,” he says, estimating about $5 per panel, depending on the scrap metal value.

If there are enough panels to feed into a PV recycling industry then the cost of processing, he hopes, might be brought low enough for it to turn a profit. On his estimate there are about 60 million panels on rooftops around the country, or $300 million in retrievable materials. “It is possible,” he says.

A local industry has sprung up. In Adelaide, Reclaim PV is using a thermal technique to separate panels and reduce them to their component parts. In Sydney, PV Industries is working out ways to get value out of old modules. At the University of NSW, researchers are testing methods for retrieving componentry, including cells, intact.

The Australian Renewable Energy Agency is also funding research into new materials that would be easier to recycle, with an ambition to replace fluorinated polymers with something that won’t produce hydrogen fluoride, a toxic gas, when burned.

About 10 million panels are being installed a year in Australia, enough to sustain a viable recycling industry. Getting the silicon back to the manufacturers will be another problem to solve down the track.

Around we go again

What about wind? The towers of power that have cropped up around the country won’t last forever, although the blades were made to withstand hell on Earth. “The blade is the part that is very hard to recycle,” Majewski says. “They are often made of fibreglass composite, silica glass fibre composite or carbon fibre composite, which are very difficult to recycle.”

Blades are enormous, up to 70 metres long, and as wind farms reach retirement after about 20 years’ operation they will be start to really pile up.

It gets worse. Majewski points out that quoting the “natural operational life” of a renewable energy asset is a shortsighted, as solar panels and wind turbine blades sometimes suffer early demise if they are unlucky enough to get in the way of hail, lightning or birds – all of which are common in Australia.

“A bird strike can knock out a blade,” he says. “If you have three blades and one blade has severe drag then the whole thing needs to be looked at otherwise the propeller starts to wobble. It’s a balancing act.”

Compared with coal-fired or nuclear power plants, it’s fair to say clean energy technology has a fairly short lifetime out in the field. “It’s an issue with all renewable energy, that they are the most exposed to the environment,” Majewski says. “With solar panels on rooftops they are the first thing hit by any hail, sandstorm, cyclone, lightning. They say they last 20 to 25 years, still producing energy at about 60-70%, but about a third of the panels are not reaching their operational life because they are knocked out by weather events or other things.”

Majewski recalls an International Renewable Energy Agency report from 2016 which showed about half of solar panels do not reach their operational life.

When it comes time to replace a roof at a commercial or industrial site or expand a residential PV system, PV panels that may have plenty of life left in them are simply taken down and replaced with new gear. It suits installers, who get to sell a load of new gear and tell the client they can expect greater efficiency, but it still means a pile of decent panels will be chucked on the scrapheap. “They are still operational, they are not damaged – they are just unwanted,” he says.

Will a second-hand market for solar modules ever take off? It’s time to think of something.