Case Study: Butendiek

Fred. Olsen Windcarrier’s specialist offshore wind jack-up vessel Bold Tern transported and installed 80 Siemens 3.6 MW wind turbines at the Butendiek wind farm in the German North Sea. Fred. Olsen Windcarrier was contracted to deliver a fully mobilised installation vessel with marine crew and crane driver, and to perform all required planning, engineering and coordination related to the operation of the installation vessel. Implementing lessons learned from the earlier Riffgat project was identified as a key deliverable in ensuring that the project was a success. Also engaged in the Butendiek project were two Bayard Class crew transfer vessels (CTV) which were used to transport installation crew and equipment throughout the project site.

The wind farm is located approximately 32 kilometres west of the island of Sylt in North West Germany in water depths of around 20 metres. The project consists of 80 wind turbines with a total output of 288 MW. Enough to power approximately 370,000 homes.

The offshore construction phase of the project began in March 2014. The first monopile foundation was installed in April of the same year and the offshore substation and cabling in May and June respectively. In September 2014, Fred. Olsen Windcarrier started installing the first of the 80 wind turbines and the commissioning phase began shortly afterwards in October 2015. The works were completed in June 2015 and the wind farm was officially opened in September 2015.

Butendiek wind farm is one of the few offshore wind projects to have been constructed and commissioned on time and on budget.

The close cooperation between the Siemens and Fred. Olsen Windcarrier project teams – as well as the experience and skill of the installation teams and Bold Tern’s crew – was a major strength, which enabled the project to tackle and solve any challenges along the way.

Despite the wind turbine installation period running through the winter months and some of the worst weather conditions in the project period, there were no major personnel incidents during the project and Bold Tern further improved her LTI-free period and HSE record in general.


Fred. Olsen Windcarrier is proud to have contributed this success story by installing all 80 Siemens SWT-3.6-120 wind turbine generators,” said Eskil Røset, Fred. Olsen Windcarrier Project Manager.

“Our HSE performance was good with no LTI incidents throughout the project,” said Jan Fredrik Platou, HSEQ Manager Offshore Wind.

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