Is Iowa’s newest turbine blade recycling method eco-friendly?

Wind energy was responsible for 58 percent of Iowa’s electricity in 2021 — the highest share for any state, according to the U.S. Energy Information Administration. It powered about 9 percent of the nation’s utility-scale electricity generation.

But the 60,000-plus wind turbines scattered across the country have a shelf life: about 20 years, depending on damage and maintenance. Repowering turbines — when they are retrofitted with updated technology — also creates waste.

Traditionally, decommissioned turbine blades have been sent to landfills. But in recent years, recycling the often hundred-plus-foot-long blades has become a new, more sustainable disposal method among companies in Iowa and the Midwest.

The most recent addition to recycling options comes from REGEN Fiber, a new Iowa business born from the Alliant Energy subsidiary Travero, which last week announced its new mechanical method for re-purposing turbine blades. Its forthcoming Fairfax facility should be able to recycle more than 30,000 tons of shredded blade materials annually once it’s operational later this year.

REGEN Fiber touts its patent-pending process as eco-friendly. Although many of the details are still under wraps, some experts say the company’s announcement is a step in the right direction for making wind energy more green by re-purposing its waste stream without using chemicals or heat.

“It's proprietary. All we can do is guess as to what it is they're doing,” said Steve Guyer, the Iowa Environmental Council’s energy and climate policy specialist. “But I hope that it is up to the billing. I think it's great that they're having a facility like that in Iowa.”

Mechanical process confidential

Representatives of Travero, a logistics company that doesn’t impact Alliant operations or customer bills, wouldn’t share many specifics about their blade recycling methods with The Gazette as they await a patent.

But they did say it’s a mechanical process that chews up decommissioned blades and blade manufacturing scrap materials and spits out shredded “virgin fibers,” those of similar quality as fibers made from manufacturers.

“(This is) a solution for both ends of the life cycle of a wind turbine blade,” said Thushan Hemachandra, Travero’s lead of marketing.

The technologies used in the process bridge several different industries, including recycling, forestry and agricultural segments. They also remove wood and foam that’s manufactured into blades and turn them into a coal fly ash replacement that stabilizes soil for construction projects.

REGEN Fiber started piloting the process in 2021 at a Des Moines facility, ensuring the fibers met performance standards for the concrete industry. The company is upgrading to a manufacturing facility in Alliant Energy’s Big Cedar Industrial Center — the largest industrial site in Iowa — next to a Travero warehouse in Fairfax.

The recycled end products can be used to reinforce materials like concrete and asphalt.

Years ago, Sri Sritharan, an Iowa State University structural engineer and Wind Energy Initiative lead, and his colleagues researched how to deconstruct turbine blades for use in concrete. A 2016 thesis from one of his students found that fibers from the blades could come at high costs and compromise the strength and durability of concrete.

Sritharan said he is pleased to see a company making more headway in the field.

“It just comes down to how cost effectively you can extract the fiber … so maybe they have figured out how to do it,” he said. “I think it's a good pathway forward.”

Comparing other recycling processes

Wind turbine blades can be recycled with heat, chemical and mechanical means, and end products vary depending on the process.

Veolia — a French company that manages water, waste and energy — recycles blades at its Louisiana, Miss., facility using heat. The structures are ground up and thrown into a cement kiln, the process emitting 27 percent less greenhouse gas emissions than traditional cement production, according to reporting by the St. Louis-Post Dispatch.

Vestas, an Oregon-based wind turbine company, has a facility in Marengo that also co-processes blade materials with cement. The company processed more than 2,000 tons of recycled materials in 2022, said Grady Howell, the company’s program manager of blade recycling.

Other facilities use chemicals to recycle their turbine blades — which could be dangerous. Jeff Woods, Travero’s director of business development, referenced the December blast at C6-Zero, a Marengo facility that says it recycles shingles, that injured up to 15 people and forced an evacuation of nearby homes.

“It's a separate industry … but that process that happened down there was chemically based,” Woods said. “Not saying our competitors, if you will, or others in the space would run into that. But they're using a similar chemical-based process.”

REGEN Fiber’s recycling process doesn’t release thermal emissions or carbon into the atmosphere like combustion does, nor does it require the use of potentially dangerous chemicals. Thus, Travero representatives call it eco-friendly.

The company’s mechanical methods also capture dust created during the process, which will be used for soil stabilization projects. Additionally, they require “reasonably low energy use” compared with other industrial processes, Woods said, sporting smaller motors. It’s unclear exactly how much energy the process requires.

“How much energy is it going to take to actually separate these fibers? I don't know,” Guyer said. “But anytime someone goes down that path, I always go back to … if we envision a 100 percent renewable future, then (not using chemical and heat) is eco-friendly.”

More recycling in the future?

Before recycling methods were an option, spent turbine blades around the country were sent to landfills. Since turbine blades are made to be durable, they’re hard to break apart and don’t compact well, which makes them take up more capacity.

A 2021 study projected that Iowa’s turbine fleets would be responsible for just under 140,000 metric tons of decommissioned blades by 2050.

MidAmerican Energy used to landfill its decommissioned blades but now recycles or re-purposes them. Although none of Alliant’s turbines have reached the end of their life span, the company said REGEN Fiber provides an option for Alliant Energy to recycle its wind blades when the time comes.

It’s unclear how many of Iowa’s landfills have taken turbine blades in the past. Des Moines’ Metro Waste Authority, which operates the biggest landfill in the state, doesn’t accept them. Neither does the Cedar Rapids/Linn County Solid Waste Agency’s landfill in Marion.

The Newton Sanitary Landfill in Central Iowa has accepted about a dozen decommissioned turbines blades in the last 10 years, said Jody Rhone, Newton’s public works director.

But piles of the parts remain around Jasper County after Global Fiberglass Solutions Inc., a company focused on fiber glass waste, fell back on its promise to recycle a combined 1,300 blades. The blades scattered around his county make Rhone skeptical of more blade recycling attempts, although he is optimistic that a company — like REGEN Fiber — could crack the code.

“I've just seen so many of these (attempts) … that never came to fruition,” he said. “I want to see it proven, done, working, have a market for the byproduct or the product — all of that before I make judgment on that.”

Brittney J. Miller is the Energy & Environment Reporter for The Gazette and a corps member with Report for America, a national service program that places journalists in local newsrooms to report on under-covered issues.

Comments: (319) 398-8370; brittney.miller@thegazette.com