A new wind turbine blade recycling strategy deploys gravity-based energy storage technology for maximum circular economy impact.
ByTina Casey
Published 21 hours ago
Oh, those pesky wind turbines, running around the countryside cluttering up the landfills with their big old unrecyclable blades. That’s the picture drawn by critics, but not for long. A new scheme is afoot that takes the old blades from a wind turbine and recycles them into new energy storage systems for wind and solar power.
What To Do With Those Pesky Old Wind Turbine Blades
Actually, the wind turbine recycling issue is a bit of a red herring. After all, the fossil energy industry has squeezed who knows how many trillions of tons of raw resources out of the ground, to be used once and never to be replaced, reclaimed, recycled, or reused again, let alone upcycled, unless you count their contribution to global carbon load as a kind of recycling, which is a bit of a stretch.
Nevertheless, the global wind industry is coming of age in an era when public policy and consumer demand are beginning to steer the global economy into a more sustainable, circular form. That pushes wind turbine blade recycling into priority status.
Wind Turbine Blades & The Circular Economy
The typical wind turbine blade lasts about 20 years, which means that a flood of spent blades is about to hit the global market.
Wouldn’t you know it, the US Department of Energy is right on top of the circular economy thing. Last month the agency’s Wind Energy Technologies office ran down some of the wind turbine blade recycling solutions bubbling up through the R&D pipeline and noted that the most effective strategy would be to design recycling and reuse into materials, components, and systems from the very beginning.
“A circular economy for energy materials also means that technology should be engineered from the start to require fewer materials, resources, and energy while lasting longer and having components that can easily be broken down for use in subsequent applications,” the Energy Department explained, citing a new lightening-resistant and erosion-resistant blade coatings developed by the firms Arctura and Resodyn Corp.
In partnership with the firm Arkema, Inc., the National Renewable Energy Laboratory has also been hammering away at a new resin-based turbine blade material that can be reduced to a liquid and reformed into new blades and other items, while reducing labor and energy inputs.
Better Ways To Recycle Old Blades
That’s all well and good for future generations of wind turbine blades, but what about those in operation now?
Yes, what about them? Fiberglass can be recovered from spent blades, but the range of application is limited because recycled fiberglass tends to lose quality.
The Energy Department has an answer for that, too. They are especially excited about a research partnership between the University of Tennessee and the firm Carbon Rivers, which involves a heat-based method for reclaiming fiberglass from wind turbines and recycling it into a high-value material for various industries including aerospace.
Extending the useful lifespan of old wind turbine blades is also part of the Energy Department’s strategy, including the use of drones and other advanced systems for monitoring, maintenance, and repair.
Hey, What About Recycling Wind Turbine Blades For Energy Storage?
Into this picture steps the Swiss energy storage firm Energy Vault, which has crossed the CleanTechnica radar previously on account of its gravity-based energy storage system.
The Energy Vault concept is similar to pumped hydro energy storage. Instead of storing electricity in a lithium-ion battery or other chemical systems, you deploy excess wind or solar power to raise something heavy upwards. When demand for electricity rises, gravity does all the heavy lifting. You allow your heavy thing — water, or in Energy Vault’s case, 35-ton blocks — to fall back to its starting point, and it generates electricity on the way down.
Pumped hydro is not a new technology, and here in the US it still dominates the energy storage field. Its advantages over battery-type systems include holding massive amounts of energy for long periods of time.
The problem is location, location, location. The Energy Department has been working on new pumped hydro technology that could enable the nation to grow the domestic industry, but for now there are few prospects for constructing new pumped hydro reservoirs in the US.
Energy Vault’s block-type gravity system could help resolve the location issue, since it does not require massive new infrastructure and copious amounts of water. All it really needs is 35-ton blocks, and those could be made from just about anything, including wind turbine blades.
Let The Wind Power – Energy Storage Mashup Begin
And, that’s where the company Enel Green Power comes in. The company, which comes under the Enel Group umbrella, has been aiming to hitch its renewable energy activities to new forms of energy storage, and it is very excited about the potential for Energy Vault to provide a home for spent wind turbine blades.
“The benefits of this solution are the same as those of a pumped storage hydro plant, but at a much lower cost, with greater possibility of being replicated in any geographical context and greater efficiency: the Energy Vault technology can even exceed an efficiency level of 80%,” EGP enthuses.
“Moreover, there are clear benefits compared to batteries: a plant of this type is not exposed to storage medium degradation (no need for augmentation over time), risk of fire, has a long lifespan of 30-35 years and its eventual dismantling will not pose particular difficulties, as the blocks are composed of inert materials and are created directly on site,” EGP adds.
Energy Vault already has a 5-megawatt demonstration facility under its belt, and it recently introduced its new “EVx” configuration that requires 40% less height than its former design. Last week the company signed an agreement with EGP to study the feasibility of a system that weighs in at “a few dozen megawatt-hours,” using material from spent wind turbine blades to form the blocks.
EGP anticipates that the study will greenlight the construction plan for a new Energy Vault project, deploying the new EVx design, in the coming year.
So, What About The Birds?
Yes, what about them? Years before the recycling issue popped up, wind power critics (looking at you, fossil energy lobby) were accusing wind turbines of causing birds to die, conveniently overlooking the fact that wind turbines are a relatively small part of a huge problem.
Practically everything that people make causes birds to die, and the worst offenders by far are buildings, overhead power lines, agricultural chemicals, and various devices used legally for hunting, among other things. For that matter, domestic cats — oh, but why beat a dead horse?
The point is that everything is killing birds. The counterfactual focus on wind turbines began about a dozen years ago and it was picked up and promoted by former President Trump, who promoted the wind turbine canard to help propel himself into office the first time.
It didn’t work the second time, which is good news for the birds, because Trump’s first and only administration spent considerable time and energy on tearing the guts out of a treaty aimed at preventing migratory bird deaths related to fossil energy activities among various other circumstances.
Oh well, water under the bridge. Migratory birds are all but certain to get a share of President Joe Biden’s love for all things sustainable, and new strategies have already emerged for reducing wind power’s relatively small share of bird impacts.
Back in 2003, for example, researchers at the National Renewable Energy Laboratory suggested that simply applying different colors and patterns to wind turbine blades could make a difference. That formed the basis for a long term study that recently demonstrated a significant reduction in risk of collision, especially for raptors.
The US Fish And Wildlife Service’s Avian Radar Project indicates that adjustments to wind turbine locations, hours of operation, and lighting can also reduce risks. Automatic shutdown systems triggered by cameras and other remote devices can help, and researchers are beginning to study how today’s generation of larger, more powerful turbines is also contributing to risk reduction.
Follow me on Twitter @TinaMCasey.
Photo: Energy Vault gravity storage system via Enel Green Power.
Wind turbines on a property near Merredin, Western Australia. An international consortium has selected a site in Australia’s south-west to build the Western Green Energy Hub. Photograph: Calla Wahlquist/The Guardian
