| Work Detail |
New bio-derivable material aims to stop wind blades from ending up in landfills
Researchers at the US Department of Energy’s National Renewable Energy Laboratory (NREL) have developed a new resin for the manufacture of bio-derivable wind blades that can be chemically recycled and the components reused.
If successful, the material could end the practice of old blades winding up in landfills at the end of their useful life.
The findings are published in the new issue of the journal Science.
The new resin, which is made of materials produced using bio-derivable resources, performs on par with the current industry standard of blades made from a thermoset resin and outperforms certain thermoplastic resins intended to be recyclable, NREL said.
The researchers built a prototype 9-metre blade to demonstrate the manufacturability of an NREL-developed biomass-derivable resin nicknamed PECAN.
The acronym stands for PolyEster Covalently Adaptable Network, and the manufacturing process dovetails with current methods.
Under existing technology, wind blades last about 20 years, and afterward they can be mechanically recycled such as shredded for use as concrete filler. PECAN marks a leap forward because of the ability to recycle the blades using mild chemical processes.
The chemical recycling process allows the components of the blades to be recaptured and reused again and again, allowing the remanufacture of the same product, according to Ryan Clarke, a postdoctoral researcher at NREL and first author of the new paper.
Clarke said: "It is truly a limitless approach if it’s done right."
He said the chemical process was able to completely break down the prototype blade in six hours.
The paper Manufacture and testing of biomass-derivable thermosets for wind blade recycling involved work from investigators at five NREL research hubs, including the National Wind Technology Center and the BOTTLE Consortium.
The researchers demonstrated an end-of-life strategy for the PECAN blades and proposed recovery and reuse strategies for each component.
The scientists wanted to make a wind blade that could be recyclable and began experimenting with what feedstock they could use to achieve that goal.
The resin they developed using bio-derivable sugars provided a counterpoint to the conventional notion that a blade designed to be recyclable will not perform as well.
Composites made from the PECAN resin held their shape, withstood accelerated weatherization validation, and could be made within a timeframe similar to the existing cure cycle for how wind turbine blades are currently manufactured.
While wind blades can measure the length of a football field, the size of the prototype provided proof of the process.
The US Department of Energy jointly funded the research through its Advanced Materials and Manufacturing Technologies Office and Bioenergy Technologies Office and their support of the BOTTLE Consortium.
Additional research and funding will allow the investigators to build larger blades and to explore more bio-derived formulations.
NREL is the US Department of Energys primary national laboratory for renewable energy and energy efficiency research and development.
NREL is operated for DOE by the Alliance for Sustainable Energy LLC. |
