We are building a sustainable future using wood. This is the reason we agreed to take part in the pilot project to use a renewable material to create renewable energy.
“Because we have decided to build a sustainable future using wood, it is only natural to be responsive to research and development. This project is a good example of what is possible to build from wood, and of which type of expertise we possess,” says Johan Åhlén, general manager of Moelven Töreboda AB, the world’s oldest glulam factory.
In partnership with the innovation company Modvion, Moelven has developed a 30 meter tall windmill tower made from glulam. On 28 April it was erected at Björkö near Gothenburg.
See the assembly
For two years Moelven Töreboda has opened up the glulam factory, contributed materials, loaned out machinery and shared expertise. This has enabled Modvion to produce and develop the 30 metre tall prototype that will be used for research. Modvion’s objective is to develop a concept that allows one to build 150 metre tall windmill towers from glulam.
“In the past two years we have gotten to know the wood’s properties even better, and we have performed and seen results from a number of interesting tests. We have contributed our expertise on large, load-bearing wood structures, and also developed our method of 3D modelling. During the construction of the windmill tower we have worked with other types of geometries than what we usually do, and that is knowledge we will take further,” Åhlén says.
Questions and answers on the wooden wind tower
Externally the tower has a tube of LVL, veneer beams with very high strength and good stiffness properties. LVL is one of the strongest wood materials on the market. Inside the tube there are glulam columns that stabilise the structure.
Wind power generally becomes more profitable the taller you build the windmills. Winds are stronger and more stable higher up, and larger rotor blades can power a larger generator. This means you can extract more energy from the windmill towers.
The challenge presented by ordinary steel wind towers is that as their height increases, they become very expensive to both produce and transport. Building modular towers in glulam lowers both the costs and greenhouse gas emissions.
The advantage of building in wood is that you can transport wind towers to places that used to be unreachable with steel structures. Large wooden elements can be stacked on top of each other. These are easier to transport and can be assembled at the construction site.
Wooden wind towers are as stable as steel towers, and can be delivered at the same cost. Because wood binds carbon and wooden tower production emits less CO2 than steel tower production, they can also contribute to huge environmental gains.
The 30 metre tall prototype on Björkö will be used for research. It is equipped with sensors and measuring equipment to find out how the structure behaves during different wind conditions and temperatures. This data will show how the tower may be scaled up.