One of 17 wind turbines in the brand new Aldermyrberget wind farm collapsed on Saturday night. The blade fell off and the wind turbine tower broke.
SWEDEN -- At the end of November, a 230 meter high wind turbine near the town of Jörn in Skellefteå municipality collapsed. The whole tower gave way and crashed to the ground.
The wind farm consists of 17 turbines from the Danish wind turbine manufacturer Vestas, which has now investigated the accident.
- The investigations show that the wind turbine overturned because a blade fell off while the wind turbine was in operation. It destabilized the turbine and caused the tower to collapse, says communications manager Anders Riis in Vestas.
Replaces all such steel inserts
But how could the blade fall off? The investigations point to some steel inserts, more specifically attached between the steel inserts and the blade rotors.
Vestas has now contacted all customers who have installed wings with this type of steel insert, and all these turbines will now be stopped. Vestas is in the process of rectifying the error.
The notification impacts about 150 wind turbines. Five of them are in Norway: Austri Vind has had to stop five wind turbines in the Kjølberget wind farm in Våler municipality, on the border with Trysil.
Five turbines stopped at Kjølberget
Like the wind farm in Jörn, the Kjølberget wind farm is completely new. It will consist of a total of 13 turbines, but the last three have not yet been installed. They will not be erected until Vestas repairs or replaces the blades.
Five of the ten turbines that are in operation have the problem turbine blades, and are therefore temporarily stopped. Vestas is in Våler and the general manager of Austri Kjølberget, Magnus Axelsson, hopes that one of the five turbines will soon be ready to be started up again.
- We do not yet know how we are affected by this. We hoped to be finished by the spring, but now we do not know exactly, said Axelsson to TU.
All blades from Vestas can be traced because each blade has an identification number. Riis stated that the type of blade in question is no longer produced.
Start-up in Jörn postponed indefinitely
Only six of 17 turbines at Aldermyrberget Wind Farm in Jörn were put into operation when the incident happened. The rest were scheduled to be put into operation in December, but the start-up has now been postponed indefinitely.
- Our focus is that all the turbines should run safely. We do not know when the power plant can start up, it depends on, among other things, the availability of cranes, the transport of new blades and the weather. A lot of snow makes the work more difficult.
Riis has not heard of wind turbines having had such accidents before.
- You see from time to time that a wind turbine can crack in a hurricane or in strong lightning. But never like this, he says.
Translation to English assisted with Google Translate