The 288MW wind farm has been under construction since March 2014, 32 kilometres west of the German island of Sylt in the North Sea. It seen total investment reach €1.3 billion.
Monopole installation was completed in July 2014 in water depths ranging from 17 to 22 metres. Design of the foundations was carried out in-house by contractor Ballast Nedam Engineering, while other aspects of construction and logistics were handled by Ballast Nedam Offshore.
The first of 80 Siemens 3.6MW tubines was installed in September 2014, with first power being exported to the German grid in February 2015.
Butendiek is connected to the German grid via the SylWin1 grid connection, which was commissioned by Siemens in April. The link also serves Vattenfall's 288MW DanTysk project.
The project is jointly owned by developer Wpd, investment firms Marguerite Fund, Siemens Financial Services, Industriens Pension (IP), Pensionskassernes Administration (PKA), CDC Infrastructure, and Swiss utility Ewz.