Carbon Rivers Commercializes Fiberglass Recycling for Retired Wind Turbine Blades

Updated on July 13, 2026 • 5 min read

Carbon Rivers has commercialized a recycling process designed to recover mechanically intact glass fiber and other reusable materials from decommissioned wind turbine blades.

Developed with support from the U.S. Department of Energy’s Wind Energy Technologies Office and in collaboration with the University of Tennessee, Knoxville, the process aims to divert composite blade waste from landfills while creating feedstocks for new industrial products.

The company reports that it has processed several thousand metric tons of material and is developing capacity to accept more than 50,000 metric tons annually at a new facility.

Pyrolysis Separates Fiber From the Polymer Matrix

Wind turbine blades are commonly manufactured from glass fiber-reinforced polymer composites, with reinforcement accounting for a substantial proportion of their weight. Their long service life and durable thermoset resin systems make them effective structural components, but these same characteristics complicate recycling after decommissioning.

Carbon Rivers uses pyrolysis to separate the glass fiber reinforcement from the surrounding polymer matrix. During the process, composite waste is heated in the absence of oxygen, breaking down the organic resin while leaving the inorganic reinforcement available for recovery.

The decomposed polymer produces hydrocarbon products, including syngas and pyrolysis oil, which can potentially be used as energy or industrial feedstocks. Steel and other materials contained in the blade are also recovered rather than discarded.

According to the company, this approach allows all major blade constituents to be directed toward reuse or further processing.

Recovered Glass Fiber Reaches High Purity

Carbon Rivers reports that its process can produce recycled glass fiber with purity levels of up to 99.9%.

Maintaining fiber length, cleanliness and mechanical integrity is important because recovered reinforcement must compete with virgin glass fiber in downstream composite applications. Excessive contamination or fiber degradation can restrict recycled material to lower-value uses.

The company says its recovered fiber can be converted into:

• Nonwoven mats and veils
• Continuous textile yarns
• Sheet molding compound
• Injection-molding pellets
• Roofing and insulation products
• Flooring and construction materials
• Marine and wind energy components

The high-purity material may also be remelted and blended with virgin fiberglass, creating another route for returning recovered glass into the fiber manufacturing cycle.

Technology Extends Beyond Wind Energy

Although the process was initially developed for retired wind turbine blades, Carbon Rivers has adapted it for composite waste from automotive, marine, infrastructure and other glass fiber-intensive sectors.

This wider application range is significant because wind blades represent only one part of the growing thermoset composite waste stream. Boats, vehicle components, pipes, tanks and construction panels face similar end-of-life challenges.

A recycling platform capable of accepting material from several industries may improve plant utilization and reduce dependence on a single waste source.

Planned Facility Targets Industrial-Scale Blade Recycling

Carbon Rivers announced plans to separate part of the operation into a stand-alone company, Windfall Inc., to develop a full-scale U.S. glass fiber recycling facility near Knoxville, Tennessee.

The proposed plant is located at a site that formerly supported Manhattan Project activities. It is intended to create domestic recycling and material production capacity while supporting employment in the region.

Project information indicates that the facility could process approximately 200 metric tons of material, equivalent to an estimated 5,000–7,000 wind turbine blades annually depending on blade size and design.

Recovered glass fiber would then be supplied to manufacturers producing new composite materials and molded components.

Why Glass Fiber Recovery Matters

Wind blade recycling is frequently discussed as a waste-disposal problem, but the more important industrial question is whether recovered materials can return to useful manufacturing applications.

Glass fiber is generally less expensive than carbon fiber, which makes the economics of recovery more demanding. A recycling process must therefore achieve sufficient throughput, material purity and product consistency to compete with established virgin-fiber supply chains.

Pyrolysis offers an advantage because it separates the reinforcement from the thermoset matrix without relying solely on grinding. Mechanical grinding can produce useful fillers, but it typically reduces fibers to short, irregular particles with limited reinforcement value.

Recovering longer and cleaner fibers creates more opportunities for higher-value reuse. However, commercial adoption will still depend on verified mechanical properties, predictable batch quality and the ability to supply material in forms compatible with existing manufacturing equipment.

Circularity Requires Markets for Recovered Materials

Large-scale blade recycling will not be achieved by processing technology alone. Recyclers also need stable markets that can absorb recovered fiber, oil, steel and other outputs.

Applications such as nonwoven reinforcements, thermoplastic compounds and construction materials may provide initial demand because they can accommodate recycled fibers with a broader range of lengths and properties.

Using recycled glass fiber in new wind turbine blades would represent a more direct closed-loop pathway, but this requires qualification against structural, fatigue and environmental performance requirements.

Carbon Rivers’ work demonstrates how composite recycling is moving from landfill diversion toward material recovery. The next stage will be proving that reclaimed fiberglass can be supplied consistently and economically enough to become a routine industrial raw material.