Recycling technologies for retired wind turbine blades: current status, environmental risks, and industrialization pathways

Over the past two decades, the global wind power industry has experienced unprecedented growth to meet the urgent demand for low-carbon energy, but this rapid expansion has also paved the way for an imminent large-scale decommissioning wave of wind turbines. Among the key challenges posed by decommissioning, the recycling of composite wind turbine blades—typically composed of glass fiber reinforced plastic (GFRP) and thermosetting resins—has emerged as a critical bottleneck that threatens to undermine the industry’s long-term sustainability. To address this pressing issue, this study conducts a comprehensive investigation into the technical status, environmental risks, and industrialization pathways of decommissioned wind turbine blade recycling, adopting an integrated research methodology that combines policy document analysis, laboratory-based technical performance evaluation, and quantitative economic feasibility assessment. The research highlights urgency with data: as of 2024, China’s cumulative wind turbine composite components (blades over 60%) exceed 6.2 million tons; annual decommissioning will surge from ~150000 tons in 2028 to over 500000 tons by 2035. A key constraint is that 80% of blade materials are thermosetting composites—highly stable and degradation-resistant, making traditional recycling inefficient. It then evaluates three mainstream technologies: mechanical crushing, the most mature method, processes blades into recycled fiber powders for building templates or aggregates but has 80% fiber strength loss and transportation costs over 30% of total expenses; pyrolysis generates toxic by-products, reduces glass fiber strength by 40%–60%, and emits much CO2; chemical recycling (solvent-based depolymerization) retains 90% fiber strength but faces high costs—over 50 million CNY for medium-plant equipment and 5000 CNY/ton processing. In addition to technical and economic analysis, the study conducts an environmental risk assessment that identifies three primary hazards: improper disposal of pyrolysis by-products, which can leach toxic substances into soil and groundwater; unregulated incineration of blade scraps, which releases harmful gases such as dioxins and particulate matter; and unclassified landfilling of intact blades, which occupies permanent land resources and may cause long-term environmental pollution. The research also identifies key industrialization barriers through stakeholder interviews and policy reviews: a minimum annual collection volume of 5000 tons is required to reach the break-even point for any recycling technology, but most provinces in China will fail to meet this threshold before 2028 due to scattered decommissioning sites; unclear ownership of decommissioned blades delays centralized collection; and the lack of dedicated waste classification codes for composite blades leads to inconsistent disposal practices across regions. The research concludes that the decommissioned wind turbine blade recycling industry is still in its infancy, with significant imbalances among technical maturity, economic viability, and environmental sustainability. To address these challenges, it proposes a three-dimensional promotion system: in the short term, prioritize the application of mechanical crushing technology in regions with high decommissioning density to quickly reduce landfill pressure; in the medium term, accelerate R&D on dynamic covalent bond resin materials that enable easier recycling of composite blades; formulate mandatory national technical standards for blade recycling and issue dedicated waste codes to standardize disposal processes; and build regional recycling hubs that integrate collection, preprocessing, and recycling to minimize transportation costs. These targeted measures not only provide a systematic solution for achieving low-carbon and high-value recycling of decommissioned wind turbine blades but also offer a reference framework for other countries facing similar sustainability challenges in the wind power industry.