World's tallest wooden wind turbine installed in Sweden

Larger turbines need towers with greater diameters to support them. While these can be transported using larger carriers for offshore projects, installing them on land poses multiple difficulties. With tunnels, bridges, and roundabouts, road transport presents multiple challenges to moving large turbine parts, making their installation difficult for onshore projects.

How can wood turbines help?

Modvion uses laminated veneer lumber (LVL) to build the thick walls of its record-setting towers. The startup uses spruce, the same wood as the Christmas tree, and compressed layers and glue to make curved sections of the tower. By controlling the grain in each of these three mm layers, the startup controls the strength and flexibility of the walls; co-founder David Olivegren told the BBC.

The curved sections can be transported easily to the installation site and then stacked up on each other to build the tower. Since wood is lighter than steel, it can be used to build taller towers with less material. Made using only wood and glue. The stacked components are held together using steel fittings.

Wood versus steel

This approach can also be used with steel, but putting together curved sections on-site adds to the cost while also increasing maintenance concerns. The other issue is the paradox associated with renewable energy solutions these days.

Larger wind turbines can generate more renewable energy but also need increased amounts of steel. Production of steel is largely done using fossil fuels, which adds to carbon emissions, the very thing that renewables are aiming to reduce.

Using wood, on the other hand, is a carbon-negative step, claims Modvion. Trees used in the production of the turbine towers have soaked up carbon dioxide from the atmosphere and will keep it locked in until it is burnt or rots away. The record-setting tower used over 200 spruce trees, and the startup said that it has planted more than it has harvested.

When installed, the wooden tower looks no different from a steel one since both get a coat of white paint for protection, and the blades are made out of fiberglass. At the demonstrating facility, Modvion has equipped the turbine with a 2-megawatt generator.

For now, the startup is focused on building taller turbine towers and has plans to construct another, even taller tower soon. By 2027, it wants to supply 100 such towers a year and 2,000 in a decade. This would be just 10 percent of the turbines expected to be installed yearly.