LASIR graduate students Chris Nash and Ray Bond viewing the real-time infrared video of the curing process at the NREL lab where the material was tested
While the benefits of wind power may seem obvious to many, the alternative energy source does come with its own environmental downsides.
To generate wind power using fields of spinning wind turbines, a substantial amount of time and energy is needed to cure the type of resin that makes the 150-foot wide fiberglass turbines both strong and durable. In addition, turbines generally wear out after 20 to 25 years of use and most of their materials are unable to be recycled.
Researchers from the Vanderbilt University, the University of Tennessee and industry partner Arkema, are working to make wind turbines more sustainable, developing a lightweight, liquid thermoplastic resin material that can seamlessly blend with glass or carbon fibers, enabling the fiberglass for wind turbine blades to be ultimately be recycled.
“What better application to look at than wind power, where we think about energy and sustainability foremost in our minds? It’s a grand challenge in composites manufacturing,” said Doug Adams, Distinguished Professor of Civil and Environmental Engineering and the Daniel F. Flowers Professor, said in a statement.
The new resin—dubbed Elium–creates its own heat and cures at room temperature without creating flaws in the fiberglass. The novel thermoplastic liquid resin makes it possible to produce continuous fiber reinforced thermoplastic parts using typical closed mold thermoset processes.
The process is also simpler than conventional techniques.
“Wind turbines are very complex systems, which is one of the reasons we want to look at ways to build wind turbine blades that are manufactured where we can make a single part with composite materials where we don’t have to have multiple materials,” said Adams.
The researchers tested the resin’s self-setting properties using infrared imaging. They also produced an algorithm that manufacturers can use to set up the process on production lines.
“This composite materials technology is exciting because it closes the loop on sustainability in wind energy,” Adams said.
The researchers will now attempt to scale up the process from test-sized components to full-sized blades.
The nation’s increasing demand for electricity has driven significant growth in the wind energy sector. According to the American Wind Energy Association, there are more than 52,000 utility-scale wind turbines operating in the U.S. The organization also said there was a 20 percent increase in U.S. wind energy jobs in 2016, which will lead to an increased focus on innovations in the wind industry, including improvements in manufacturing efficiency, workforce training and end-of-life recycling.
Arkema will showcase the new resin at the JEC World 2018 conference in Paris from March 6 to 8. They first displayed the resin in 2016 in the form of a 6.5-meter prototype sailboat.
Simulation tools will be developed in conjunction with Purdue University and Convergent Manufacturing Technologies. A newly commissioned facility at the Colorado School of Mines (CSM), the Vacuum Assisted Resin Transfer Molding (VARTM) lab, will fabricate proof of concept panels in conjunction with Johns Manville and Arkema, while the NREL National Wind Technology Center (NWTC) will manufacture full-scale blade components in the new Composites Manufacturing Education and Technology (CoMET) facility.
