Giving retired turbines a second spin

What do you do with 91 decommissioned wind turbine nacelles that are difficult to recycle? A team of engineering students has the answer: turn them into public e-bike charging stations.

The idea won a 12-week circular design challenge hosted by Meridian Energy, in partnership with the University of Auckland and Engineering for Sustainable Development.

The students' proposed solution would repurpose the nacelles – the part of a wind turbine that houses the generator, gearbox and controls – from Meridian Energy's Te Rere Hau Wind Farm on the Tararua Ranges.

Using two nacelle shells per station, they designed a durable, weather-protected charging hub where users can park, pay and charge e-bikes and e-scooters.  

The winning team comprised five doctoral candidates from the Department of Mechanical and Mechatronics Engineering: Mohamed Salman, Xingxing Lin, Yuejian Zhang, Junqi Pan and Zhongjian Ling.

"The brief was to find a way to reuse or repurpose the nacelles, which are made from composite materials that are much harder to recycle than other parts of the turbines," says Salman.

"We spotted an opportunity in the growing micromobility sector, where public charging for e-bikes and e-scooters still lags behind EV infrastructure.

"Now we’ve potentially developed a way to give these nacelles a second life. It shows how circular design can unlock value from materials that might otherwise end up in landfill." 

The challenge attracted 20 teams from the University of Auckland, with students receiving weekly mentoring from industry and academic experts throughout the 12 weeks.

Salman's team was mentored by Liz Timings and Cait Maclennan from Meridian Energy.

The team earned a $3,500 cash prize for their winning design, which Meridian is now exploring as part of the Te Rere Hau repowering project, alongside other ideas.

The more than $600 million project will replace the existing turbines with 39 larger, three-bladed turbines, leaving the nacelles redundant.