World’s Tallest Wooden Wind Turbine in Skara, Sweden Starts Turning

It is probably anyone’s imagination that something that is made with the same wood as a Christmas tree, and is held together by glue can be something other than a piece of furniture. Well, this is not some mindless flat-pack furniture, but a wooden wind turbine that has now started to turn. According to Modvion, which is the Swedish start-up that has just built the turbine tower, it is the World’s tallest turbine tower. On top of that, it is made by using wood for wind power and it is the future. Otto Lundman, the company’s chief executive says “It’s got great potential.” According to him, it is 150m (492ft) to the tip of the highest blade which has a 2-megawatt generator on top. This has also just started supplying electricity to the Swedish grid which can provide power for about 400 homes. However, it is the dream of both Lundman and Modvion to take this wind turbine to the next level.

Several very similar-looking turbines are turning on the horizon near the Modvion project. However, the key material to them is steel, and not wood, just like it is for almost all turbine towers around the world. Steel due to its nature of being durable and strong, has enabled massive wind firms and turbines constructed on both land and at sea. But steel also has its limitations, particularly for projects that are on land. With the increasing demand for taller turbines harvesting stronger winds with larger generators, the diameter of the cylindrical steel towers to support them has increased as well. When there are just too many bridges, roads, tunnels, and roundabouts, many in the wind industry are saying that getting steel for turbines has become difficult. This creates a huge impact on how tall the steel turbines can be, hence making Modvion look for an alternative.

From the outside, there are not many obvious differences between the wooden turbine and the steel one. Both have a thick white coating that protects them from the elements and blades that are made primarily from fiberglass. In both, these are attached to a generator, producing electricity when it turns. However, it is only when the tower is visited from the inside, that the differences become clear. The primary difference is seen on the walls which have curved raw wood finish, whereas the steel ones have walls like saunas. The 105m (345ft) wooden turbine tower’s strength comes from the 144 layers of laminated veneer lumber (LVL), making the walls thick. Modvion varying the grain of each of the 3mm-thick layers of spruce says that it has been perfectly able to control the wall’s flexibility and strength. The company co-founder – and former architect and boat builder – David Olivegren with a smile says “It’s our secret recipe.”

At the factory, it was explained that the thin layers of wood had been compressed and glued together to make the curved segments. These pieces are then taken on the site and glued together into cylinders. Then, they are stacked upon each other to make the tower. Olivegren says, “Wood and glue is the perfect combination, we’ve known that for hundreds of years.” “And because using wood is lighter [than steel] you can build taller turbines with less material,” he continued. According to Lundman and Olivegren, the towers can be built in much smaller, and more easily transported modules by using glue and wood. However, Dr Maximilian Schnippering, head of sustainability at Siemens Gamesa who is also one of the world’s largest turbine manufacturers, says that more pieces mean more trucks, people, and more time for installations.