Researchers develop method for chemically recyclable wind turbine blades

Researchers develop method for chemically recyclable wind turbine blades

by Clarence Oxford

Los Angeles CA (SPX) Sep 01, 2024

Scientists at the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) have identified a viable pathway for creating wind turbine blades from bio-derived materials that can be chemically recycled. This innovation could prevent old blades from ending up in landfills, instead allowing their components to be reused.

The study, published in the journal ‘Science’, details the development of a new resin made from bio-derived resources. This resin matches the performance of traditional thermoset resins used in current wind blade manufacturing and exceeds the capabilities of some recyclable thermoplastic resins.

The NREL team constructed a prototype 9-meter blade using their new biomass-derived resin, named PECAN (PolyEster Covalently Adaptable Network). This resin integrates seamlessly with existing manufacturing processes. While conventional blades have a lifespan of about 20 years and are often mechanically recycled, PECAN offers the advantage of being fully recyclable through mild chemical processes.

Ryan Clarke, a postdoctoral researcher at NREL and lead author of the study, noted that the chemical recycling process can completely break down a prototype blade in just six hours. “It is truly a limitless approach if it’s done right,” Clarke explained.

The paper, titled “Manufacture and testing of biomass-derivable thermosets for wind blade recycling,” highlights contributions from five NREL research hubs, including the National Wind Technology Center and the BOTTLE Consortium. The researchers demonstrated effective end-of-life strategies for PECAN blades and proposed methods for recovering and reusing each component.

“The PECAN method for developing recyclable wind turbine blades is a critically important step in our efforts to foster a circular economy for energy materials,” said Johney Green, NREL’s associate laboratory director for Mechanical and Thermal Engineering Sciences.

Research into PECAN resin began with a focus on creating a recyclable wind blade. The scientists experimented with various feedstocks to develop a resin that not only could be recycled but also matched or exceeded the performance of traditional materials. Nic Rorrer, one of the corresponding authors, emphasized that recyclable materials do not necessarily underperform. “Just because something is bio-derivable or recyclable does not mean it’s going to be worse,” he said, addressing concerns about potential deformation, or “creep,” over time.

The PECAN resin composites maintained their shape, withstood rigorous weather testing, and could be produced within the same timeframe as current wind turbine blade manufacturing processes.

While large wind blades can be as long as a football field, the successful production of the 9-meter prototype demonstrated the process’s scalability. “Nine meters is a scale that we were able to demonstrate all of the same manufacturing processes that would be used at the 60-, 80-, 100-meter blade scale,” said Robynne Murray, the study’s second corresponding author.

The research team included Erik Rognerud, Allen Puente-Urbina, David Barnes, Paul Murdy, Michael McGraw, Jimmy Newkirk, Ryan Beach, Jacob Wrubel, Levi Hamernik, Katherine Chism, Andrea Baer, and Gregg Beckham, all from NREL.

Funding for the research was provided by the U.S. Department of Energy’s Advanced Materials and Manufacturing Technologies Office and Bioenergy Technologies Office, in support of the BOTTLE Consortium. Future research will focus on developing larger blades and exploring additional bio-derived resin formulations.

NREL is the U.S. Department of Energy’s primary national laboratory for renewable energy and energy efficiency research and development, operated by the Alliance for Sustainable Energy LLC.

Research Report:Manufacture and testing of biomass-derivable thermosets for wind blade recycling