Sharpening-up blade recycling

The wind power industry has spent decades working on the design and manufacture of turbine rotor blades, refining its production processes to handle complex composite materials at ever-growing size and volumes.

The Re-Wind programme is researching how blade materials can be reused (pic: RE-Wind)

Hand-in-hand with this has been the painstaking development in techniques to transport these huge components from manufacturing plant to wind farm site, and then install them at increasingly lofty heights.

Rather less time has been spent on working on this process in reverse — removing the blades from turbines that have reached the end of their operating life, transporting them from the wind farms, and then finding the places and the methods of disposing the non-biodegradable materials in a sustainable way.

Research in this area grows more urgent as the number of turbines approaching decommissioning increases.

This is where Emma Delaney comes in.

Delaney is a Geography PhD student at Queen's University in Belfast and is part of the Re-Wind project, an interdisciplinary research team of experts drawn from Queen's, together with University College Cork, the Georgia Institute of Technology and City University of New York.

"My focus is on the Geographic Information Science (GIS) element of the programme," says Delaney.

"But the overall aim is to gain a greater general understanding of the decommissioning of wind turbines — predicting the waste quantities we will be dealing with, and the different types and combinations of materials involved."

"Before we get to the issues of how we recycle or reuse these materials, we need to build up a geographic database of precisely where these ageing turbines are currently operating, and how and where the blades can be transported after dismantling.

"Should they be transported whole, or broken-up on site? Many wind farms are in pretty remote locations, far from the centres where they can be recycled or repurposed, which brings its own environmental problems in terms of transport," she says.

Three 50-metre blades of a typical 2MW onshore turbine — modest by today's standards — contain around 20 tonnes of fibre-reinforced polymers (FRP).

According to Re-Wind's research, up to 40 million tonnes of this material will have required disposal by 2050. Landfill and incineration are not environmentally viable options at this scale.

"It's a really big problem," says Delaney. "We're looking at the best options."

A key part of the Re-Wind programme is research into how blade materials can be reused, particularly in buildings, infrastructure (including bridges), landscape and public art. While there is still a great deal of work to do in this area, there are precedents for innovative developments.

For example, a number of the blades from the pioneering Vindeby offshore wind project, decommissioned in 2017, have been recycled as sound barriers on roads in Denmark.

The high density of the glass-fibre material — compared to the mineral wool generally used in noise barriers — lends itself well to this application.

And last year, trade association WindEurope established a cross-sector platform with the continent's chemical and composite materials industries to explore new ways to recycle turbine blades.

But, as Delaney says: "This is a big problem, and we need to address it before it becomes a bigger one."

Emma will be speaking at in Berlin, 18-19 February 2020.

Book your ticket today to hear more on end-of-life solutions, as well as how to optimise energy output from the design stage and throughout the full lifecycle of your blades.Â