Location: In the German North Sea, approximately 37 km from the island of Borkum and 55 km from the north-western coast of Germany.
Developers and Owners
Developers: Ørsted and PNE AG.
Owners: Ørsted holds a 50% ownership stake, while Kirkbi and the Oticon Foundation hold 32% and 18% respectively.
Operational Details
Status: In commercial operation since October 2015.
Number of Turbines: 78 turbines.
Turbine Specifications:
Manufacturer: Siemens Gamesa Renewable Energy (originally Siemens)
Model: SWT-4.0-120
Power Capacity: 4 MW each
Rotor Diameter: 120 meters.
Total Nominal Power: 312 MW.
Infrastructure and Foundations
Foundations: The wind turbines are installed on fixed foundations. Phase I uses monopile foundations, while Phase II uses suction bucket jacket foundations.
Offshore Substation: The wind farm features an offshore substation with two main transformers. The substation platform is supported by an eight-legged steel jacket and piles.
Power Transmission
Voltage Levels: The 34 kV power generated by the turbines is increased to 155 kV by the offshore substation. This power is then converted into 320 kV DC electricity at the DolWin alpha high-voltage direct current converter station and transmitted to the Dörpen West Converter station via HVDC cables. Finally, it is converted back into AC power and supplied to the German 400 kV main grid.
Environmental and Social Impact
Energy Supply: The wind farm is expected to power approximately 320,000 German households.
Construction and Contractors
Construction Period: Construction began in 2013, and the project entered commercial operation in October 2015.
Contractors Involved:
Turbine Supplier: Siemens Gamesa Renewable Energy
Installation Vessel: A2Sea's SEA INSTALLER
Foundation Installation: GeoSea
Cable Supply: Nexans
Transportation: Combi lift and others.
Maintenance and Operation
Operator: Ørsted
Maintenance Contract: Siemens Gamesa Renewable Energy is the O&M contractor for a period of 10 years (initially 5 years as per some sources, but extended).