NSF-BSF: CAS: Integrated Environmental and Economic Evaluation of Scalable Circularity Transitions for Wind Turbine Blade Composites

Wind energy currently provides 10.2% of the nation's electricity, with further growth expected. The process of electricity generation using wind turbines emits 10-100 times less CO2 per kWh over its lifetime compared to electricity from fossil fuels. While wind energy offers tremendous environmental benefits, it also poses challenges in terms of solid waste management.

Wind turbine blades are primarily made of glass fiber reinforced polymer composites (FRPC) to provide durability and operational lifetimes beyond 20-years. However, this durability also makes them difficult to recycle. With 5 million tons of blades to be retired in the coming decades, “Wind Energy Tech Recycling Research & Development” was identified as a critical area in the recent US Bipartisan Infrastructure Law.

This project aims to address this challenge by exploring various end-of-life (EOL) management options for wind turbine blades, focusing particularly on recovering the glass from the blades. The approach involves a combination of experiments and modeling to understand the overall environmental footprint and cost-effectiveness of different recycling methods.

Options will include recovery of clean glass fibers that can either be downcycled or remelted in cullet to form high-strength fibers, as well as existing options of landfilling, cement co-processing, and mechanical recycling. Project outcomes will inform the development of collection and recycling infrastructure in the United States.

This project encompasses aspects of both Industrial Ecology and Green Engineering. The team will combine experiments and modeling to quantify relationships between pyrolysis/calcination conditions and glass fiber properties, environmental impacts, and cost. This information will be incorporated into an integrated framework for assessment and trade-off analysis of EOL pathways at the regional and national scale.

The team will (1) quantify relationships between thermal recycling process conditions, recovered glass properties, and energy required/recovered by experimental analysis of real-world field samples of blade waste; (2) quantify the life cycle environmental and economic impacts of near-horizon glass recycling and downcycling EOL options for wind turbine blades using life cycle assessment (LCA) and technoeconomic analysis (TEA); and (3) quantify supply chain and circular economy impacts of near-horizon EOL options by analyzing prospective scenarios with an integrated discrete event simulation model combining dynamic material flow analysis, LCA, and TEA. This project has the potential to significantly impact recycling approaches and infrastructure for composite materials across many sectors including energy, construction, automotive, maritime, and defense.

Wind turbine blades are a useful model system because they comprise a large and concentrated waste stream, and this work will help guide their EOL management. The project will also result in education and training of multiple PhD and undergraduate students. Outreach will include an annual renewable energy series at a West Philadelphia middle school and Philly Materials Day, designed for K-6 students from the School District of Philadelphia.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.