Aussie tech could give second life to turbine blades in high-tech medical, agri uses

Wind turbine blades could one day end up as biodegradable nano-coatings for seeds, that hug nutrients close before melting safely into the soil.

It’s just one of the concepts to come out of a University of New South Wales (UNSW) research team, but it’s a very long way from a paddock full of wind turbines and it is not yet clear if it can deliver the recycling needs sought by the owners of Australia’s oldest wind farms.

The issue around recycling came into focus in February this year when renewable energy company Pacific Blue said it would decommission the Codrington wind farm, an 18.2 megawatt (MW) generator that started operations in 2001. 

While concrete, cable and tower recycling options are available now in Australia, the composite-fibre turbine blades are still a challenge: the biggest issue is cleaning the fibreglass fibres from the resin that holds them together. 

And this is where Ballarat-based PVC Separation potentially comes in, a small company with a technology that can separate PVC plastics out so they can be used again. 

Pacific Blue has funded two trials to the tune of $50,000 a piece to see if the company’s chemical process, currently at the proof of concept stage used for turning PVC tarpaulins into a reusable material, might work on blades and then what the clean fibreglass might be used for.  

“They gave me a piece of a blade to see if I could separate it, so I used my patented process and it worked,” says PVC Separation founder Dennis Collins.

“Then we started looking at where to go from there.”

Collins sent samples of the resulting fibreglass to CSIRO last year and to UNSW, and both came back saying it was 87 per cent clean of composite materials.

“[UNSW] were looking for samples to do a project they’re working on [and] found our samples were the cleanest they had,” Collins says. 

PVC Separation founder Dennis Collins with cleaned fibreglass from a turbine blade. Image: Pacific Blue

It’s the UNSW project which wants to turn blades into biodegradable materials that can be reused in agriculture and medicine – another idea is as a coating for nano-drugs so medical payloads are delivered to the right place in the human body.

These future applications are only possible however, if the team led by UNSW associate professor Tushar Kumeria and PVC Separation can raise the grant funding to figure out the details in between.

Blades into fibreglass slush

In a video produced by Pacific Blue, Kumeria, says he wants to make a material that will biodegrade within weeks or months, as opposed to turning blades into surfboards or shoes that can’t later be recycled at all. 

But the issue is getting access to the polymer – the plastic – inside the composite blade. 

Stepping into this section of the supply chain is Collins.

“Blades are soaked in a chemical, the chemical cleaned and reused again. Once the chemical is drained away, then we add a catalyst to it. The catalyst causes the separation,” Collins says. 

“We have a pop-corning effect [where] it swells up, then we use our mechanical device for the final separation.”

The whole process takes about nine minutes – for a 40-50mm piece. 

PVC Separation founder Dennis Collins with the separated slush of wood, resin and fibreglass from a turbine blade. Image: Pacific Blue

PVC Separation has a pilot plant in Belgium and one in Ballarat, which can be re-tooled from tarps to turbine blades. 

With the two trials confirming his process can handle composite fibre blades as well, Collins says they’re now looking for a $7 million Cooperative Research Centres Projects (CRC-P) grant to see how to commercialise the process, which requires a few more moving parts.  

Collins says a commercial process would require blades to be cut into 4 metre lengths on site so they can be carted away in a truck, then put through a series of shredders to get them to a small enough size for the chemicals to do their work. 

Collins says the Melbourne-based Manhari Metals empire is keen to licence the technology once it’s commercialised. 

No pressure at all

As the first to decommission a decently-sized wind farm in Australia, Pacific Blue is under pressure to do it well.

But with no blueprint for best-practice or even government policy as a guide, it’s also figuring out many of the details as it goes. 

A community meeting in Portland this week was reportedly well attended by curious locals, but also attended and documented by representatives from wind farm-sceptic groups which are watching the process closely and with a deeply suspicious eye.

A spokesperson for Pacific Blue notes there is currently no international or global standard for the decommissioning of wind farms, and while examples are beginning to appear in Europe and the US, they may not be right for Australia. 

“We are learning from those experiences overseas, however we are yet to determine the solution that suits both the community’s and our needs,” an emailed statement to Renew Economy says.

“As a result, we are funding two streams of research, one with UNSW to recycle fibreglass and the other with PVC separation to remove the composites.

“This research is now underway and we hope our funding helps establish new methods that may in the future be suitable for recycling blade materials in Australia.”

Pacific Blue has another two years before Codrington needs to be out of the ground, at which time it hopes to have established a best practice for the rest of the industry to follow.

If you wish to support independent media, and accurate information, please consider making a one off donation or becoming a regular supporter of Renew Economy. Please click here. Your support is invaluable.