Historically, wind turbines haven't been particularly climate-friendly, in both their construction and their after life. But two new companies are seeking to switch the market on to fully recyclable wooden towers and blades, that are also require much less energy to create.
Swedish start-up Modvion has developed a system to build turbine towers using sections of laminated wood. Timber towers are lighter than steel and can be constructed in sections to be slotted together on site. This makes taller, more powerful turbines cheaper and easier to transport, reports New Scientist.
Plus, producing a timber tower instead of steel one generates 90 per cent less carbon dioxide emissions, according to Modvion. And when the turbine comes to the end of its life, the modular segments from the tower can be reused - as load-bearing beams in the building industry, then after that they could become partition walls and then paper. “That’s basically our vision – to have a six or seven step cascaded reuse of the material, for many hundreds of years, so that we get as much benefit out of each and every cellulose fibre before we return it to the atmosphere,” says Erik Dölerud, an engineer at Modvion.
The firm already has one 30-metre tower up and running on the Swedish island of Björkö, which was erected in 2020. The pilot project helped the firm catch the attention of turbine maker Vestas, which invested in Modvion last year. Now work is underway on a 100m tall turbine for Varberg Energi, which is due to be completed next year and should pave the way for commercial rollout of timber towers.
Meanwhile, German start-up Voodin Blades has a vision for wind turbines to be built with wooden blades, which are lighter and easier to dispose of than fibreglass blades.
It is building its first 20m long blades, which will be installed on a test turbine by the end of the year. Work is also underway on an 80m long blade that could be used in commercial wind farms.
Eventually, turbines could be made from wooden towers and wooden blades, says Dölerud. “I think it’s a very good idea,” he says.