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Reactive infusible thermoplastics have the potential to be advantageous for wind turbine blade composites because they are recyclable at end of life, can have reduced manufacturing costs, enable thermal joining and have similar, and in some cases better, structural properties than traditional thermoset epoxy composites. However, these materials are new to the wind industry and there is risk to investing in a material that has not been validated at a blade scale. Industry cannot adopt a new material such as this without large-scale validation and demonstration of system-level advantages in cost and/or performance. This paper presents structural characterization of a 13-m thermoplastic composite wind turbine blade compared to an identical geometry thermoset epoxy blade. The results of this comparison showed that the flatwise structural static performance and the fatigue performance of the two blades were similar, but the thermoplastic composite blade had increased damping compared to the epoxy blade, which may result in reduced operational loads.

Two-part, in-situ reactive thermoplastic resin systems for composite wind turbine blades have the potential to lower the blade cost by decreasing cycle times, capital costs of both tooling and equipment, and energy consumption during manufacturing, and enabling recycling at the end of the blade life. This paper describes a techno-economic model used to estimate the cost of a thermoplastic wind turbine blade relative to a baseline thermoset epoxy blade. It was shown that a 61.5-m thermoplastic blade costs 4.7% less than an equivalent epoxy blade. Even though the thermoplastic resin is currently more expensive than epoxy, this cost reduction is primarily driven by the decreased capital costs, faster cycle times, and reduced energy requirements and labor costs. Although thermoplastic technology for resin infusion of wind turbine blades is relatively new, these results suggest that it is economically and technically feasible and warrants further research.

Reactive thermoplastics are advantageous for wind turbine blades because they are recyclable at end of life, have reduced manufacturing costs, and enable thermal joining and shaping. However, there are challenges with manufacturing wind components from these new materials. This work outlines the development of manufacturing processes for a thick glass fiber–reinforced acrylic thermoplastic resin wind turbine blade spar cap, with consideration given to effects of the exothermic curing reaction on thick composite parts. Comparative elastic properties of these infusible thermoplastic materials with epoxy thermoset materials, as well as thermoplastic coupon components, are also included. Based on the results of this study it is concluded that the thermoplastic resin system is a viable candidate for the manufacturing of wind turbine blades using vacuum-assisted resin transfer molding. Significant gains in energy savings are realized avoiding heated molds, ability for recycling, and providing an opportunity for utilizing thermal welding.