Undoubtedly, wind turbines are an essential key to our fossil fuel-free future. Nonetheless, there are a number of challenges to solve in achieving their sustainability, making wind turbine blades a unique example of the good, bad, and nerdy. To make solar, wind, and other renewable power sources fully sustainable, you have to consider every phase, from siting to production to end-of-life disposal. About 85% of a modern wind turbine’s component materials (steel, copper wire, electronics, and gearing) are recyclable or reusable. Its blades – usually three 50- to 80-m-long blades made of fiberglass and carbon girders bonded between painted fiberglass shells and protected by an epoxy resin – are the rub. This combination of different materials and the blades’ strength makes their separation for the recovery of workable glass fibers physically and chemically challenging. The blades’ weight and length also make transporting them complicated.
Why not cut the blades into pieces on-site, you might ask? Although feasible, this doesn’t solve all the transportation and recycling problems and calls for enormous – and expensive – vehicle-mounted wire saws or diamond-wire saws similar to those used in quarries. The vast majority of blades reaching the end of use are consequently either stored in various places or taken to landfills (although they account for only a tiny fraction of U.S. municipal solid waste).
Various companies have taken up the challenge:
In 2020, PacificCorp and MidAmerican Energy partnered with Tennessee-based Carbon rivers to recycle some of the utilities’ spent turbine blades. With the help of Department of Energy (DOE) grant funding, they have since developed new technology to break down and reuse fiberglass from used turbine blades. As of October 2022, we know that the project, which has achieved 99.9% recycled glass fiber purity from various waste streams, has an added bonus: the process has been adapted for automotive, marine, structural, and glass waste materials and other future uses, including making recycled glass fiber into nonwoven fabrics, continuous textile yarns, automotive sheet molding compounds, and plastic injection molding pellets. Recycled glass fiber can also be remelted and mixed with virgin fiberglass for additional uses. And the cherry on top? The Carbon Rivers site outside Knoxville, TN, is slated to become the first full-scale U.S.-based glass fiber recycling facility as Windfall Inc. originally supported nuclear weapons production under the Manhattan Project!
- Re-wind, a U.S., Irish, and Northern Irish university partnership, has developed some interesting civil engineering project ideas for reusing and repurposing fiberglass blades: using decommissioned blades as part of powerline structures or towers or even roofs for emergency or affordable housing. The blades have also been used in pedestrian bridges along greenways in Northern Ireland.
- WindEurope, which represents the EU’s wind industry, has partnered with the European Chemical Industry Council (Cefic) and European Composites Industry (EuCIA) to develop new methods to reuse blade materials. In May 2020, the consortium published “a comprehensive report...focused on the wind turbine cycle” called Accelerating Wind Turbine Blade Circularity. Check it out!
- In Germany, a partnership between Geocycle (Hocim AG) and the company Zajons built a plant about a decade ago to develop the concept of recycling turbine blades into cement. This consisted of sawing blades on the decommissioning site to reduce transportation logistics and costs, a promise of 100% recycling, and reduced CO2 emissions from cement co-processing by replacing cement raw materials with the recycled blades and burning biogas instead of coal.
Other mechanical recycling, sovolytic, and pyrolytic solutions are also being developed to provide additional end-of-use handling options. So, Vestas Wind Systems A/S is a member of the 10-partner Decom Blades initiative launched in January 2021, a three-year project focused on shredding wind turbine blades for reuse, using shredded blade material in cement production; and a pyrolitic method to separate the composite material. CETEC (Circular Economy for Thermosets Epoxy Composites) is an initiative developing a new resin technology for future blades in a circular economy: disassembling blade composites into fiber and epoxy, then breaking down the epoxy into its base components through chemcycling for reintroduction into turbine blade manufacturing. GE Renewable Energy has begun recycling blades by shredding them into raw material for use in cement manufacturing, while a city in the Netherlands has turned old blades into a playground, and Cork, Ireland, is experimenting with using retired blades to build bridges.
Still, a few clouds cast shadows on this otherwise rosy picture:
- Global Fiberglass Solutions Inc. began producing EcoPolyPellets® in the U.S. in 2019 and then anticipated being able to process 6,000-7,000 blades a year at each of its two plants in Texas and Iowa. Today, piles of spent blades are still waiting in fields in Sweetwater, TX, and three towns in Iowa, with the corporation facing a lawsuit brought by Iowa’s Department of Natural Resources for illegal storage of the spent blades after failing to meet deadlines to recycle the blades, bury them in landfills, or ship them out of state.
- A municipal landfill outside Casper, WY, has been the resting place for more than 1,120 blades with another 250 expected to be added in the coming year.
Unregulated wind turbine blade disposal and the lack of U.S. policy regarding blade recycling and reuse overall, thereby contributing to the status quo of storage or disposal in landfills, are major problems. Legal measures are needed to have the blades go round in a circular economy.