Stronger and lighter: Wooden towers to be used for bigger wind turbines

Leading European timber technology companies have made headlines this week with plans for new wooden wind turbine towers that will be capable of supporting turbines from 4.2MW to 6.4MW.

Swedish company Modvion announced that its latest wooden wind turbine tower, which had been engineered to support a V162 – 6.4MW turbine from the Vestas Enventus platform, had been evaluated by independent certification body TÜV SÜD and received a design evaluation conformity statement.

Utilising Laminated Veneer Lumber (LVL), which uses thicker walls to deliver greater strength per weight and cost compared to steel, Modvion’s wooden turbine towers deliver surprising upsides over traditional steel towers.

Wood actually has a higher specific strength, enabling lighter construction, whereas tall steel towers need extra reinforcement so as to carry their own weight. Similarly, modular steel towers are fitted together using thousands of steel bolts which subsequently need regular inspection, while modular wooden towers need only glue.

Moreover, at the end of the turbine’s lifespan, the wooden towers can be dismantled and reused as high-strength beams for the building industry.

The new tower was designed to demonstrate that Modvion’s wooden wind turbine tower technology can be scaled up to support the most powerful onshore wind turbines.

Having secured independent certification, Modvion will now turn its attention to adapting the design for series production before beginning production on wooden towers that can support hub heights of up to 219 metres.

“Having this stamp of approval for one of the largest onshore turbines available is a great leap forward,” said Otto Lundman, CEO at Modvion.

“Our modular wind turbine towers dramatically reduce CO2 emissions by replacing steel and concrete with wood, whilst enabling highly efficient, taller installations without transport bottlenecks.”

Also announced this month, Hasslacher Green Tower, a subsidiary of leading European timber industry giant Haslacher Group, entered into a partnership with RE Technologies, the global research and development organisation of Senvion India, which will see the two companies develop timber-hybrid towers for the European market.

Haslacher Group bills itself as “a globally active innovation leader in the field of intelligent and integrated system solutions for modern timber construction”, while Hasslacher Green Tower focuses specifically on using composite materials to meet the needs of solutions that are subjected to high dynamic loads.

The two groups will develop timber-hybrid towers specifically designed for Senvion India’s newly launched 4.2M160 wind turbine and which will boast hub heights of between 170 and 200 metres.

Current plans expect to deliver a prototype 170-metre tower for installation in 2026 and a 200-metre prototype tower in 2027. Built from a highly efficient spatial framework structure they will significantly reduce the amount of material used in turbine towers and provide for a high level of prefabrication and optimised logistics.

Each timber-hybrid tower is expected to displace over 500 tonnes of CO2 and will also minimise the technical requirements for installation, requiring only a single crane, thus eliminating the need for crane pads, boom downs, and storage areas by up to 50%.