The failure of retaining bolts led to a nacelle casing falling off an Adwen M5000 turbine at the 60MW Alpha Ventus offshore wind farm in the German North Sea, according to the project’s co-operator EWE.
The company said that it is currently unclear why the bolts failed and caused the entire nacelle casing to break off in April.
The wind farm operators, which also include Eon and Vattenfall, are now preparing to start work shortly on a replacement campaign.
A walk-to-work service operation vessel will be deployed to enable technicians access to the turbine.
The technicians are expected to fasten loose parts and then re-energise the machine to position it for an exchange of the rotor star and the nacelle.
Parts that fell off the turbine will be recovered from the seabed.
Once the damaged nacelle reaches Adwen’s facilities in Bremerhaven, the manufacturer will investigate further the reasons behind the fall.
It is still unclear when the remaining five Adwen M5000 machines at Alpha Ventus, which are running in idling mode, will resume regular operations.
Image: Alpha Ventus
Bolts ‘failed’ Alpha Ventus turbine
By EBS