Australia flies the flag for used wind turbines

Wind has become a major energy force in Australia – accounting for more than 11.7% of the total energy generated in 2021 – but there is an expanding elephant in the room.

After their final rotations, the giant structures of wind turbines need a resting place. And with blades at least 35m in length, and towers that top 150m, that’s not an easy task.

A 2022 University of South Australia study predicts tens of thousands of wind turbines will end up in landfill by the end of the decade unless answers are found.

There are estimates that more than 40 million tonnes of blades will need to be disposed of worldwide by 2050.

“The same features that make these blades cost-effective and reliable for use in commercial wind turbines make them very difficult to recycle in a cost-effective fashion,” University of South Australia’s Professor Peter Majewski says.

Some countries have found novel new purposes for their old turbine blades. Poland and Ireland have used them for bridges. Denmark has turned blades into bike shelters, and the Netherlands has used them for play equipment. There are proposals to use blades for sound barriers, glamping pods and cattle feeders.

To manage the issue in the long-term, the first recyclable blade has been developed by Siemens Gamesa. GE also has one in the pipeline.

But in its own no-nonsense way, Australia has been implementing a small-scale, no-frills solution for years. Some of the rest of the world’s problematic end-of-life turbines have been refurbished and are quietly providing energy to chicken hatcheries and carrot farms, garnet mines and piggeries around the country.

This month, the arrival of five Enercon wind turbines at Port Gregory, near Kalbarri in Western Australia, attracted attention. The turbines have been refurbished after they were dismantled from a wind farm in the Netherlands, and will be used as part of the Moora microgrid supplying renewable energy to local users.

The project, which will include a wind, solar and battery microgrid, will power a piggery, citrus farm and potentially other farms in Moora.

“The turbines are significantly lower cost than new machines, but more importantly, are more readily accessible,” Advanced Energy Resources (AER) managing director Luca Castelli says. “We can have a turbine dismantled in Europe and recommissioned in Australia in less than 12 months as opposed to traditional turbine supply agreements which can extend to 18 plus months from order to delivery (not including installation).

“Further, the trend in newer and more modern turbines is towards larger generation capacities (4MW+). For our projects, which are typically less than 10MW, we required smaller turbines (less than 2MW). These are more readily available in the used turbine market.”

With significant upgrading, Moora Energy expects to get at least 20 years of additional life out of the turbines. They undergo refurbishment of the blades, and the mechanical and electrical systems, as well as corrosion treatment.

“They will essentially be near-new when refurbished,” Castelli says.

While this is AER’s fourth shipment of second-hand wind turbines, Castelli is quick to point out that there has been a lot of pioneering work already done in this space.

West Australian company Blair Fox managed a project to procure 20 Enercon wind turbines from the San Giorgio La Molara wind farm in Italy, which are now in operation at the West Hills and Karakin wind farms 150km north of Perth.

The company also imported 19 Enercon wind turbines from the Vila Lobos Wind Farm in Portugal which were refurbished and installed at the Beros Rd Wind Farm at Warradarge, 270km north of Perth.

And the use of “second-hand wind” goes even further back in Tasmania, where Joule Logic manager, Paul Fulton, has been involved in projects using pre-loved wind turbines since the early 2000s.

Projects have included a turbine in the rural town of Sassafras powering a chicken processing facility, a turbine at Wesley Vale powering a horticulture business, one at Sisters Creek providing energy to a chicken hatchery, and projects at Woolnorth and Flinders Island feeding directly into the distribution network.

Fulton says second-hand turbines were used because they are smaller, there is a steady supply because of “repowering” projects in Europe and beyond, specialised cranes are not needed, and they are cheaper, easier to install, and less difficult to transport.

“I think that second hand turbines have a place in the Australian market for remote mining sites and other industrial operations,” he says.

“They are ideal for that application because at those sites they do not have to comply with the National Electricity Rules, and also because at a mine site they are typically competing with gas or diesel-generated energy, so they are very cost competitive. At those sites, there are generally reasonably competent technical people to maintain the turbines as well.”

Fulton says the refurbished Vestas have been in operation at some sites for 27 years with “no date in mind for pulling them down yet”, but he warns there are challenges.

Old turbines typically do not have low-voltage ride-through capability, which is required under changes to the National Electricity Rules.

Read more in Cosmos: What becomes of decommissioned wind turbines?

“That is a problem,” he says. “Before buying a turbine it is recommended that much research is done to ensure that it can be connected under the current National Electricity Rules.

“No modifications were required for the turbines [in the projects we have worked on], other than new SCADA supervision software and new communications modems that handle 3G/4G networks. We chose Vestas for the projects developed because Vestas spares are still available and supported. There are many people who are familiar with Vestas technology, and many third-party suppliers of new and refurbished parts for the turbines.

“We used Enercon for the Flinders Island project because we were lucky enough to be able to purchase the wind turbine from the Australian Antarctic Division because they had bought three turbines but only managed to install two at Mawson Base.”

While turbines that have lived a life on the Netherlands canals or the hills of Portugal are a practical option for smaller operations in Australia, Fulton warns they will never be suited to massive wind production.

“Small, pre-loved turbines cannot compete with new large scale wind farms on the cost of energy produced,” he says.

“If they could, they would not be being dismantled to make way for new turbines.”