Wind power is viewed as a key component of the energy mix in a more sustainable future. However, wind turbines themselves pose considerable hurdles to achieving truly sustainable electricity generation. One of these hurdles is the waste produced when wind turbine blades reach the end of their lives. While many decommissioned blades are currently buried in landfills, efforts are underway to develop more sustainable end-of-life strategies.
Since wind turbine blades are primarily manufactured from glass fiber / epoxy matrix composites and are built to withstand extreme weather, they can’t be easily recycled or repurposed. In the United States, retired wind turbine blades are primarily sent to one of a small number of landfills that accept them in Iowa, South Dakota, or Wyoming.
Around 8,000 blades will be decommissioned in each of the next three years in the United States alone, and once they are buried in a landfill, they will remain there forever. This number will increase as wind power grows as a portion of the country’s overall energy mix. It is thus essential to identify and develop alternatives for decommissioned turbine blades, rather than simply replacing one environmental challenge with another.
Search for Alternatives
A variety of alternatives to landfills are being explored. In Europe, some blades are simply burned as fuel in power plants. This is not ideal as the blades have low energy content, and burning fiberglass emits dangerous pollutants.
One promising alternative is recycling the blades for use as a raw material in cement manufacturing. In December 2020, General Electric Renewable Energy signed an agreement with Veolia to recycle blades removed from its onshore turbines in the U.S. using such a process.
Veolia will shred the blades and use the resulting material in the coproduction of Portland cement. 65% of the blades will be used as raw material (replacing sand and clay), and 28% will be used as energy for the kiln, resulting in almost 95% of the blade being reused. Additionally, this process results in 27% lower CO2 emissions versus the traditional cement manufacturing process and a 13% reduction in water consumption.
By recycling a single blade weighing 7 tons, this process saves nearly 5 tons of coal, 1.9 tons of limestone, 2.7 tons of silica, and a ton of additional mineral-based raw materials from being used to produce cement.
Another company tackling this issue is Global Fiberglass Solutions (GFS). GFS has developed a process to break down blades and turn the raw material into a variety of new products, including composite panels, railroad ties, and plastic composite pellets. GFS can process and recycle 99.9% of a wind turbine blade.
A third company, Carbon Rivers, has partnered with utility companies PacifiCorp and MidAmerican Energy to find sustainable solutions for their retired wind turbine blades. The U.S. Department of Energy (DOE) recently granted funding to researchers at the University of Tennessee to work in partnership with Carbon Rivers.
The group aims to build a facility that can recycle the blades and use the repurposed materials to make products such as sports equipment and vehicle parts. GE Renewable Energy will also partner with Carbon Rivers over the next few years.
Until these solutions begin operating at scale, most decommissioned wind turbine blades will continue to be buried in landfills. Some policy proposals to help drive adoption of these solutions include more stringent requirements for manufacturers for designing for end-of-life recycling and increased support of research into blade recycling infrastructure (like the DOE funding mentioned above). Wide adoption of these emerging blade recycling technologies can help turn wind power into a truly sustainable energy source.