Oldenburg, Munich and Hamburg, Germany Temperature rises in the sliding bearings of the Areva Wind M5000 turbines were spotted in the spring, leading to two of the 12 5 MW turbines being taken off line.
Turbine houses, or nacelles, were then replaced at six of the turbines. This operation ran from September until 12 October, although the procedure to replace the nacelles using jack-up vessels took only a few hours.
“Together with the contractor, Areva Wind, we implemented the know-how we acquired during the construction phase to facilitate an expedient offshore solution,” said Dr Claus Burkhardt, the overall project leader of Alpha Ventus.
Installation of the 12 turbines was completed on 16 November, 2009, and the farm has so far generated over 140 GWh.
Alpha Ventus consists of six Areva M5000 offshore wind turbines and six REpower 5M turbines. The project was completed by a consortium of EWE, E.ON and Vattenfall Europe, and represented an investment of €250 million ($356 million).