Wind Turbine Blades Using Recycled Carbon Fibers: An Environmental Assessment
Lightweighting is accepted as an effective strategy to design environmentally conscious products, such as lightweighted passenger cars with enhanced fuel efficiency.1 Material lightweighting in the wind energy industry opens up the possibility of manufacturing large wind turbine blades with higher power generation capacities.4 This ability to design lighter products and differentiate them based on improved sustainability performance has led to the increase in demand for lighter and mechanically stronger materials like carbon fibers.
As a result, the wind energy industry is expected to emerge as the largest consumer of carbon fibers with its market share surpassing that of the aviation sector by 2022.5 Carbon fibers demand has also increased because the mechanical performance of longer wind turbine blades can only be met when structural components are fabricated using a carbon fiber-reinforced polymer.7,8
However, the incorporation of carbon fiber-reinforced polymer composites into wind turbine blades poses sustainability challenges to the wind energy industry in the long term because their predominantly cross-linked structure renders them difficult to recycle. Disposing of carbon fiber-reinforced polymer wind turbine blade scrap via conventional routes (landfilling or incineration) is neither an environmentally sustainable alternative nor beneficial from a circular economy perspective in the long run.9−11
It is preferential to reuse recovered carbon fiber in new lightweighting applications, such as manufacturing of wind turbine blade components, where the fundamental principle of circular economy (large volumes of recycled material to be used longer) can be justified. This study innovatively assesses the environmental performance of wind turbine blades with parts made from recycled carbon fiber materials.
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Photo credit: Ian Van Landuyt