Adwen Turbine Accident Probe Gets Down to Nuts and Bolts

The nacelle of the damaged Adwen M5000 (AD 5-116) wind turbine will be replaced on the Alpha Ventus, Germany’s first offshore wind farm, with preparatory work scheduled to begin soon, the wind farm’s operator said.

As reported earlier, a rear part of the turbine’s nacelle broke off and fell into the sea. The operator has now revealed that the AV 07 turbine lost the nacelle roof, the sides, and the bottom in the incident.

What has been determined so far is that the bolts holding together the parts that fell off were broken or torn, however, it is still unclear why this happened, the operator said.

The operator plans to send a Service Operations Vessel and a crew of specialist technicians to carry out the disassembly of the damaged nacelle and the installation of the new one.

The damaged nacelle and the broken parts which have been gathered will be transferred to Bremerhaven where a team from Adwen will examine the unit in detail to determine the exact cause of the incident. The evaluation of the data recorded by the Condition Monitoring System is already in progress.

The 60MW Alpha Ventus wind farm comprises six Adwen M5000 wind turbines and six Senvion 5M turbines. The remaining five Adwen M5000 turbines, currently in the idling mode, are undergoing visual inspections.

Commisioned in April 2010, the wind farm is operated by Deutsche Offshore-Testfeld und Infrastructur GmbH & Co. KG (DOTI), a joint venture between EWE, E.ON and Vattenfall.