NREL Creates Recyclable Resin for Sustainable Wind Blades

With wind energy rapidly gaining momentum, the development of a recyclable, bio-derived resin like PECAN can be a boon for the wind sector, potentially revolutionising the wind blade manufacturing.

The  researchers at the US Department of Energy’s National Renewable Energy Laboratory (NREL) have developed an innovative resin named PECAN (PolyEster Covalently Adaptable Network), which is a new material, made from bio-derivable resources. This allows for the creation of wind blades that can be chemically recycled.

The findings, published in 'Science', highlight that the resin performs comparably to the current industry standard of thermoset resin-based blades and surpasses certain recyclable thermoplastic resins. To demonstrate the practicality of PECAN, the researchers built a prototype 9-meter wind blade using this biomass-derivable resin, showing that it integrates well with existing manufacturing processes.

Traditionally, wind blades have a lifespan of around 20 years, after which they are typically shredded for use as concrete filler. However, PECAN offers a significant advancement with its ability to be recycled through mild chemical processes, enabling the components to be reused repeatedly. Ryan Clarke, a postdoctoral researcher at NREL and lead author of the paper, emphasised that this method could be a 'limitless approach' if implemented correctly. Remarkably, the PECAN resin was able to break down the prototype blade in just six hours.

The research, funded by the US Department of Energy's Advanced Materials and Manufacturing Technologies Office and Bioenergy Technologies Office, involved collaboration across five NREL research hubs, including the National Wind Technology Center and the BOTTLE Consortium. The study not only demonstrated the end-of-life recyclability of PECAN blades but also proposed strategies for recovering and reusing each component.

This new resin challenges the conventional belief that recyclable blades compromise performance. The PECAN resin maintained its shape, passed accelerated weatherisation tests, and could be manufactured within the current production timelines for wind turbine blades. Although the prototype was smaller than typical wind blades, which can span the length of a football field, it provided proof of concept for the new material.

With further research and funding, the team hopes to develop larger blades using this bio-derived resin and explore additional formulations.