In a surprising twist of events, wind-farm owners across Europe are opting to delay the decommissioning of their aging turbines, a strategy aimed at maximizing electricity generation during a time of soaring energy prices triggered by geopolitical tensions, particularly the conflict in Ukraine. This revelation surfaced during a recent industry meeting where stakeholders gathered to discuss the future landscape of the wind energy sector.
According to Wind Europe, a prominent industry representative, the decommissioning of old turbines fell significantly short of expectations in 2022. A mere 454 megawatts (MW) were retired, a stark contrast to the anticipated 1.5 gigawatts (GW). This decision to extend the operational life of turbines marks the third consecutive year of decommissioning undershooting predictions in Europe. Simultaneously, North America experienced a drop in turbine decommissioning from 668MW to 276MW, as reported by the Global Wind Energy Council.
While this deferral provides a temporary reprieve, it intensifies an existing challenge faced by the wind energy sector — the recycling and disposal of turbine blades. Typically designed to endure 25 years of service, the extension of turbine lifespans prompts a closer examination of sustainable solutions for the impending waste crisis.
Recycling Specialists Grapple with Blade Disposal
The majority of wind turbine components can be recycled, but blades pose a unique problem. Composed primarily of glass fibre or carbon-fibre reinforced plastic, these materials, chosen for their durability, present a formidable challenge for traditional recycling methods due to their resistance to cutting or grinding.
Historically, outdated blades have found themselves in landfills or subject to incineration. An attempt was made in Germany to process blades into cement, but the capacity was limited, and the value assigned to the blades remained low.
In the United States alone, an estimated 8,000 blades were anticipated to be retired this year, alongside an additional 4,000 in Europe, resulting in approximately 40,000 tonnes of material. However, the final figures may see adjustments based on wind farms securing extended planning permissions.
Looking ahead, projections indicate a global annual waste of around 200,000 tonnes of blades a decade from now, accentuating the magnitude of the impending challenge. This issue is exacerbated by the growing size and weight of the current generation of blades compared to their predecessors.
Addressing the Challenge: Repurposing Gains Traction
In response to the blade waste dilemma, repurposing has emerged as a viable and growing solution. This involves dismantling old blades and using the components to create new products. Examples include the replacement of steel girders in bridges, with researchers collaborating with Cork County Council to repurpose blades for a pedestrian bridge in Cork city.
The innovative use of three 14-metre blades from an older turbine in the construction of a bridge in Poland and another in Draperstown, Northern Ireland, demonstrates the potential of repurposing. Additionally, ongoing research explores transforming used blades into electricity poles, capitalizing on the material’s non-interference with communication signals. This alternative not only reduces land usage but eliminates the need for guy wires.
The spectrum of possibilities for repurposing extends beyond infrastructure projects to include animal-feeding troughs, bus and bicycle shelters, cattle partitions, glamping pods, housing materials, noise barriers, public furniture, railway ties/sleepers, thermal insulation, and wave attenuators.
Innovations in Blade Recycling: A Path Forward
As the wind energy sector grapples with the challenge of recycling turbine blades, researchers and manufacturers are actively exploring solutions. The primary obstacle lies in separating polymers from binding resins, a process critical to effective recycling.
Two main methods, pyrolysis (heating in an oxygen-free environment) and solvolysis (resin separation using a solvent), have been explored. However, both methods result in fibres weaker and more expensive than new ones.
Manufacturers such as Siemens Gamesa, General Electric, and Vestas are developing resins that promise easier recovery. Despite claims of success, details regarding their methods remain scant, leaving the outlook for these innovations uncertain.
Another avenue of exploration involves crafting blades from thermoplastic polymers, which are more flexible and repairable compared to current thermoset polymers. Initial tests of a 14-metre blade in the U.S. show promise, offering the potential for on-site manufacturing to reduce transportation needs.
Beyond Wind Turbines: A Broader Recycling Challenge
While wind-turbine blades represent a significant waste challenge, the issue extends beyond the energy sector. Fibre-reinforced plastic materials utilized in boats and planes are similarly underutilized in recycling efforts, contributing to a broader environmental concern.
As the industry navigates the immediate need for repurposing solutions, ongoing research into more efficient and sustainable recycling methods holds the promise of rendering these waste challenges obsolete. The convergence of innovative approaches, technological advancements, and a commitment to environmental stewardship may pave the way for a greener and more sustainable future in the wind energy sector.