How to Better Recycle Wind Turbines and Solar Panels

As solar and wind power have taken off around the world, so has the backlash against the waste they generate when the equipment has to be retired. Stories about wind turbine graveyards and solar panels piling up in landfills have gone viral, with anti-green activists seizing on the images as evidence that renewable energy isn’t really that good for the planet.

While retired panels and blades are a form of waste, they are a drop in the bucket of garbage generated each year by everything from consumer goods to construction materials. Using wind and solar cuts many more tons of carbon than their production and disposal create, and they’re vastly cleaner than fossil fuels.

Still, that doesn’t mean clean energy can’t get cleaner. Companies from France to Taiwan are experimenting with new materials, industrial processes and design concepts to reuse or recycle solar and wind equipment. They’re spurred by the desire to create a greener, more circular economy, but also by the promise that there’s money to be made reselling the valuable materials hidden in these discarded parts. And companies are preparing for a future when the boom in renewables means more clean-energy firms will pay for someone to deal with their trash.

“We have resources in our waste,” says Nicolas Defrenne, chief executive officer of the French solar recycling state-backed nonprofit Soren, which organizes the collection of used panels and makes sure they get dispatched to different recycling plants. “We really need to make an effort to go and get those strategic materials”

Solar panels and wind turbines are state-of-the-art equipment built to survive in open fields, the ocean and on rooftops for decades. That resiliency also makes them harder to break down when it comes time to dispose of them.

To capture as much wind energy as possible, blades are made of the same materials as jet planes so they can be long and light. Solar panels are a space-age concoction of special metals and glass that are 10 times more efficient than plants at capturing the sun’s rays and turning them into usable energy.

“On the upside, all of this holds together very well for a long time,” says Antoine Chalaux, chief operating officer of ROSI, a company that recycles solar panels based in Seyssins, a two-hour drive from Lyon. “On the downside, it makes it hard to recycle.”

Of the two, wind blades are the bigger problem. A giant blade, swirling hundreds of meters in the air, can become a real hazard after operating for too many years. It’s less risky to leave a solar panel sitting a few feet off the ground or on a rooftop past its expiration date. In fact, some solar panels built in the 1980s are still generating electricity. Many functional panels taken down in the US and Europe can be sold at a discount in emerging markets for example in African or Latin American countries.

The issue when it comes to solar is scale. The industry is growing almost twice as fast as wind. That resulted in 97,000 tons of panels being thrown away by 2020, a figure that could rise to 2.6 million tons by the end of the decade according to the National Renewable Energy Laboratory — as much as the weight of seven Empire State Buildings.
“In 20 years, when we’ll need to change all these panels, we’ll have a challenge of orders of magnitude bigger than today,” said Chalaux. “Right now we’re at the beginning.”

There’s also an economic incentive to recycle solar panels. Each cell contains small amounts of valuable metals such as silver, copper and aluminum. That’s what led We Recycle Solar Inc. to develop a deafening destruction line on the outskirts of Yuma, Arizona. Panels that can’t be resold are fed into a machine with three dozen hammers that shatter them into fragments. The pieces are then sorted, sifted, crumpled and crushed until the basic materials can be extracted.

The process is crude, but it works. Some weeks the company sells as much as 22,500 kilograms (50,000 pounds) of aluminum as scrap metal; glass is turned into a gritty powder that can be used as a sandblasting material. The company is profitable, says Chief Executive Officer Adam Saghei, and it’s looking to build four more facilities across the US in the next five years.

“It’s a great business model,” Saghei says. “We’re not going to run out of supply.”

But We Recycle Solar’s approach is rudimentary compared with what’s happening in France. Europe has made it illegal to send solar panels to a landfill. While many US panels end up buried underground, in France, the solar industry established Soren to oversee the entire lifecycle of a panel.

ROSI is an important part of that process. Panels can be recycled either by crushing them or through “delamination,” where a large machine with a hot blade separates their glass from their “laminate” — from which precious materials can be extracted. ROSI uses lasers, high heat and chemicals to separate out metals like silver while preserving them in as pure a state as possible, allowing them to be resold to solar manufacturers for reuse in future cells.

The process is more expensive but allows ROSI to recover more of the scarce metals, resulting in about four times more value extracted compared with crushing, Chalaux says. The company can recycle about 3,000 tons of panels a year and is looking to construct new facilities in Germany and southern Europe.

Brian Donohue’s journey into the world of recycling renewables grew from his experience on the floor of the New York Board of Trade in the early 2000s, where he was a commodity merchant dealing in everything from oil to gold and sugar.

Years later, in places like Texas, Kansas, Iowa and New Mexico, utilities began tearing down the first generation of modern wind turbines and replacing them with newer, more efficient versions. Companies would come to Donohue, whose background made it easy for him to find buyers for most of the materials that went into their windmills. There are mature markets for recycling metals, concrete and industrial lubricants.

But the long, contoured blades were made of materials he hadn’t dealt with before — high-tech, lightweight composites made of plastic and glass fibers. “The fiberglass, that was the sticking point,” Donohue says.

At the end of a product’s life, there are four main options: reuse it, recycle it, burn it or throw it away. It was unsafe to reuse the blades after years of wear and tear in the field, and recycling composites is incredibly difficult. So most companies either ground down the blades or tossed them in landfills.

But turbine blades can be the size of airplanes, and people were starting to complain about massive piles of them towering over rural landscapes. The tiny town of Sweetwater, Texas, became a flashpoint after a company that had promised to process blades instead abandoned thousands that then became a breeding ground for rattlesnakes and mosquitoes.

So Donohue and his partner formed a company, Canvus, which uses sliced-up blades as frames for public furniture such as park benches and planters. Canvus hopes to eventually find new homes for as many as 2,000 blades a year, up from the hundreds it’s recycled since 2022. Other examples of creative reuse abound, including bridges in Ireland, bike shelters in Denmark and fish farms in China. But repurposing old blades only takes care of a fraction of the 8,000 turbines retired in the US every year, let alone the wave of future retirements.

One possible long-term solution is taking shape in Taiwan, where Swancor Holding Co. is one of several companies globally developing new, recyclable products that mimic the physical properties of current blade material.

Swancor was founded by Robert Tsai, who grew up in a small village in the remote mountains of central Taiwan. As a boy, he would trek two hours to bring buckets of drinking water back to his home, a chore that taught him the value and scarcity of natural resources. Tsai had a knack for chemical engineering in college, which eventually led him to create Swancor focused on inventing new materials.

To make the fiber-reinforced plastic composite that underpins the modern wind industry, hundreds of long threads of glass or carbon fiber are pulled together and dipped into a plastic goo, which is heated until it forms a thin plank that can be hundreds of meters long.

That goo, known as a thermoset resin, isn’t easily converted back to a liquid once it hardens — it’s like trying to unfry an egg. When blades have reached the end of their life, that hardened resin makes it difficult to extract the fibers, which are both valuable and emissions-intensive to produce.

Swancor and other firms, such as India’s Aditya Birla Group, are developing a new resin that can be chemically dissolved, allowing the fibers to be used again in products like car bumpers and camping gear. The process emits about 2 kilograms (4 pounds) of carbon dioxide for every kilogram of reclaimed carbon fiber, compared to more than 55 kilograms of emissions to produce virgin material, Swancor says.

A small demonstration factory at Swancor’s headquarters showcases its nascent technology. Scraps from the manufacturing floor are fed into a large metal cauldron holding a chemical solvent, where the resin is broken down. A spinner then helps to separate the mixture, producing bags full of black clumps of carbon fibers soft enough to be teddy bear stuffing, which can be used to make polyester.

Swancor’s material is still in the testing phase. Companies including Siemens Gamesa, Vestas Wind Systems A/S and Ming Yang Smart Energy Group Ltd. are trying it out to make sure it can withstand the rigors of real-world use. But Swancor is bullish — it opened a second recycling line at one of its factories in mainland China this year.

“People criticized wind as ‘trash energy’ because of the unrecyclable blades,” Tsai says. “I wasn’t convinced and invested in our R&D efforts, and after several years, we were able to make it. We changed the material.”