Wind Turbine Blades Could Soon Appear on Your Street

One day soon, you may be waiting for a bus underneath something that in a previous life has been sailing high above the ocean waves.

Thanks to the work of a new joint project between researchers in the U.S., U.K. and Ireland, spent blades from wind turbines could soon be appearing reincarnated as street furniture such as bus stops and power line masts, as they seek to save millions of tons of them going to waste.

While wind turbine towers and motors are made from metal and can be recycled once decommissioned, the blades are non-recyclable, meaning that unless they are put to good use, tens of thousands of costly blades will be otherwise incinerated.

As renewable energy production is stepped up in the move towards net zero, experts from the British Isles, Georgia Technical College and City University in New York have teamed up to find ways of bringing that wastage down.

"There was talk about crushing up the blades and using them as aggregates in concrete, and that I thought was a waste," Marios Soutsos, a professor of materials at Queen's University, Belfast, Northern Ireland, told Newsweek, adding that the material they are made from "is a very expensive, very high-strength material, so we don't just bury it...so we thought of repurposing rather than recycling."

The team in Belfast have already successfully built two bridges, each using two blades as supports, designed for small ditches and waterways—including one that is already in use in Ireland. When they stress-tested one of the structures, 32 concrete blocks weighing more than 34 tons were not able to break it.

Putting the Renewable Back in Renewable Energy

Wind turbine blades are made from Glass Fiber Reinforced Polymer (GFRP), an advanced and lightweight material with a design life of 20-25 years—meaning many of the wind farms established in the 1990s will soon be in need of a refit.

According to the U.S. Geological Society, as of 2022 there were 70,800 wind turbines in the U.S. alone—suggesting between half a million and over 2.9 million tons of blades are already set to go to waste, depending on their size, unless they can be saved.

Soutsos said the project had already been quoted 450 blades becoming available every year in Ireland alone, but that their relatively short design life was likely out of caution from operators. Testing his team did on GFRP found that degradation was "not that significant."

"I guess the companies are worried that there may be damage to them," he added. "There have been cases where wind turbine blades have been damaged, there have been tears on them and so on—and those repairs are expensive."

Soutsos said GFRP has a "very high tensile strength" and is light compared to other materials, making it suitable for outdoor structures. The only problem is, once formed into blades, it cannot be reshaped.

While this has posed an intriguing challenge to material engineers, it means those already being decommissioned are currently either burned or sent to landfill.

"The tendency nowadays is to structurally use it to burn cement plumes instead of landfilling because it costs a lot of money to landfill," Soutsos explained. "Burning it is not a good thing to do because you are burning the polymer, and it's actually the fibers that are the expensive component in the blade."

As well as bridges and street furniture, the team is looking to repurpose the blades as outdoor playgrounds and bike shelters. Globally, the project estimates that by 2042 there will be 8.6 million tons of blades that will need a new function.

"The issue of end-of-life of wind turbine blades is becoming a significant sustainability concern for wind turbine manufacturers, many of whom have committed to the 2030 or 2040 sustainability goals that include zero-waste for their products," the multinational team of researchers wrote in a recent paper about the project.

They added: "Repurposing is the most sustainable end-of-life solution for wind turbine blades from an environmental, economic, and social perspective."

A Concrete Problem

Wind turbines are not the only facet of the move to clean energy that has raised a new set of environmental and social concerns. Some have warned that the mining of rare earth elements such as lithium and cobalt—used to make lithium batteries for electric vehicles and energy storage—could have an impact on the natural habitats where they are found and the human rights of those who are mining them.

Even though researchers are looking for ways to minimize the waste from wind turbine blades, Soutsos noted that there was a large, heavy component of the structures that has yet to find a secondary purpose: their concrete foundations.

"They are relatively huge [to] prevent the turbine overturning," he said, adding: "As with electric vehicles, we cannot go net zero—there is always going to be some carbon footprint of your structure."

One potential solution to both these problems is already being developed, though. Touchwind, a startup in The Netherlands, is looking to produce a single-bladed wind turbine that sits on a buoy which is anchored directly to the sea floor.

The proposal is designed to operate like a helicopter rotor, rising and falling with the wind and able to turn in whatever direction it is facing. The company said in July it hopes to use 3D printing technology to make the anchors out of sand and shell material that would naturally be found on the seabed.