Vestas & Co’s new wind turbine blade recycling solution: How does it work and can it make emission-intensive aviation sector greener?

On 8 February, Vestas and its CETEC partners made headlines as they completed a project that brought a novel chemical disassembly process for wind turbine blades a step away from commercialisation. It is time we look more closely at what exactly in the two-step process is new, where else it can be applied, and if this single solution could change the wind industry’s recycling landscape.

In this article:

• New chemical process result of 2016-2020 project developing new blade materials
• Two-step solution relies on widely available chemicals and novel chemcycling process
• Aeroplanes might soon become ‘greener’
• Can this solution alone solve industry’s blade recycling struggle?

What brought attention to the news is the fact that this solution could address one of the biggest sustainability points that the industry is trying to address through different solutions, primarily focusing on avoiding landfilling.

Namely, more than 90 per cent of a wind turbine can be recycled or reused and the blades, made of thermoset composites containing fibre and epoxy are keeping the wind energy industry from becoming even more environment-friendly.

So far, wind turbine OEMs and wind farm operators have brought forward new, recyclable blades that will be manufactured in the future, such as those by Siemens Gamesa and the ZEBRA project, and restored to the cement production industry to reuse the blades and not to them in a landfill.

Information about the new chemical disassembly process was first shared in 2021 when Vestas and its CETEC (Circular Economy for Thermosets Epoxy Composites) initiative partners – the epoxy producer Olin, the Danish Technological Institute (DTI) and Aarhus University – presented the key points as they kicked off the project to bring forward a fully scoped solution ready for industrial adoption.

The starting point for the novel solution, however, goes back to 2016, when the two companies and the two research organisations teamed up under the DreamWind (Designing REcyclable Advanced Materials for WIND energy) initiative.

The DreamWind project, which was also partly funded by Innovation Fund Denmark just as the subsequent CETEC, was looking into the development of new recyclable composite materials for future wind turbine blades. The primary goal was to find new ways to produce reusable composite materials and ensure that recycled materials could be used in the production of new blades.

Under the DreamWind initiative, this was to be achieved by using “smart components” that could be disassembled after a blade reaches the end of its service life.

The solution which this earlier project was developing is based partly on the production of stimuli-responsive materials, which can be disassembled after use, and partly on incorporating bio-based resources in the new materials.

The high-strength materials are recycled and kept as a high-value resource either in their native resource chain or fed into another relevant resource chain, feeding other industries.

The year after the DreamWind project came to a close, the four partners embarked on a new journey under CETEC and said the DreamWind initiative set the stage by developing the new technology that was already in 2021 hailed as a technological breakthrough.

In the press release from the beginning of this month, Mie Elholm Birkbak, Vestas’s Specialist for Innovation & Concepts, said the chemical process relied on “widely available chemicals” which are the basis of the overall two-step disassembly process that makes up the new recycling solution.

Our sibling news site offshoreWIND.biz has contacted Vestas to learn what chemicals are being used, as well as to find out the timeframe in which Vestas expects to have the solution commercialised, with the company yet to respond.

These chemicals are the key part of the newly discovered approach in chemcycling epoxy resin.

The chemcycling process itself is what is new in the novel solution and is employed after blade thermoset composites have been previously disassembled into fibre and epoxy. The new chemical process then further breaks up the epoxy into base components similar to virgin materials.

What this new, second-step process does is deconstruct the highly stable polymer chains of epoxy into molecular building blocks. These building blocks are then easily processable and can be used to produce new epoxy, which will have the same quality as the original material, according to information Vestas shared a couple of years ago as the CETEC project kicked off.

“Avoiding the loss of valuable molecular complexity in such a way is a highly desirable concept and an important step to sustainable materials”, the company said.

The new chemical process is highly suitable for industrialisation and can therefore be scaled up quickly, according to Vestas, which is now working with its CETEC partner Olin and Stena Recycling to set up the solution for commercial use.

Given the push within the wind energy industry to make the blades recyclable, the implications for the wider industry are undeniable.

Whether the entire two-step process or the newly discovered epoxy chemcycling will be proprietary to Vestas and/or its partners is unknown at this time. OffshoreWIND.biz inquired about this as well and, as already mentioned, is awaiting a response from the company.

However, Vestas did make a more broad reference in the press release from 8 February on enabling the blade material currently sitting in landfills or still in active use to be disassembled and reused. The company also notes the industry-wide reach and benefit of the new solution on its website.

“As we are the sole wind OEM in this project, Vestas will lead the industry toward implementation of a circular economy, enabling a significant reduction of our shared environmental footprint”.

Aside from wind energy, the new solution could bring more sustainability to other industries using epoxy and thermoset composites, such as the automotive and aviation sectors.

“When fully developed, the solution may also have an impact for other industries that rely on thermoset composite in production, such as automotive and aviation”, Vestas stated in the press release from 2021.

Being one of the more emission-intensive sectors, the aviation industry is currently working on decarbonising as much as possible, mainly by exploring the use of alternative fuels. Currently, the sector is well ahead with testing and using sustainable aviation fuel (SAF), with the first projects to test hydrogen announced.

Last year, Airbus revealed that it was developing a hydrogen-powered fuel cell engine, which could be part of the zero-emission aircraft that Airbus had announced a few years ago would enter service by 2035. 

Furthermore, Rolls Royce, one of the top manufacturers of jet engines, is working with easyJet to develop hydrogen combustion engine capabilities capable of powering a range of aircraft, including those in the narrow-body market segment.

With one of the main factors being fuel efficiency, regardless of which fuel fills up the tank, aviation has been using epoxy-based composites for decades due to the small weight of components made of this material. They were first used for secondary structures of aircraft, before also becoming the building blocks of fuselages and wings.

Since they share this common thread, the wind energy and aviation industries have been tapping into each other’s expertise for a long time, and it is no different with looking for sustainable solutions for composites.

Both relying on laws of aerodynamics, aircraft and wind turbine makers are in a joint quest to make the parts using composite materials as sturdier and as lightweight as possible. And thermoset epoxy composites used by both sectors are a stumbling rock towards being more sustainable.

Now, with the new chemcycling process going beyond disassembly into composite materials, aeroplanes and other aircraft might employ one more achievement from the energy industry, along with clean fuels.

While the new chemical process has been welcomed as one solution to replace them all, to some extent, Vestas states on its website that the solution developed under the CETEC projects will be used simultaneously with that developed within the DecomBlades project to approach blade recycling from different directions.

DecomBlades was also launched in 2021 and in this project, Siemens Gamesa and Vestas are working side by side to avoid landfilling and find new recycling solution.

The cross-sector consortium behind DecomBlades consists of Ørsted, LM Wind Power – a GE Renewable Energy business, Vestas Wind Systems A/S, Siemens Gamesa Renewable Energy, FLSmidth, MAKEEN Power, HJHansen Recycling, Energy Cluster Denmark (ECD), University of Southern Denmark (SDU) and Technical University of Denmark (DTU).

The three-year project is focusing on three processes to establish a recycling industry for composite materials: shredding blades so that the material can be reused in different products and processes, use of the shredded material in cement production, and employing pyrolysis to separate the composite material under high temperatures.

“In the short- to mid-term, it is important to further scale and mature technologies in projects such as DecomBlades to ensure that blades are diverted from landfills. In contrast, CETEC can contribute to circular epoxy value chains, where the material properties of epoxy can be maintained so that recycled materials can be reused in the production of new blades. You can read more about each initiative below”, Vestas states on its website.

Floorplan for Offshore Energy Exhibition & Conference 2023 is now open

Coming this November, OEEC 2023 will once again gather professionals from the oil & gas, LNG, offshore and floating wind, marine energy, and hydrogen industries in Amsterdam.

Check the OEEC 2023 floorplan