Nordsee One

Location and Site Characteristics

The Nordsee One offshore wind farm is situated approximately 40 kilometers north of the island of Juist in the North Sea, within the German territorial waters. It is located between the Terschelling-German Bight and the German Bight Western Approach traffic separation scheme (TSS).

Ownership and Operation

The wind farm is owned by Northland Power from Canada, holding an 85% stake, and RWE Innogy (now part of RWE), holding a 15% stake.

Capacity and Turbines

The Nordsee One wind farm consists of 54 Senvion 6.2M126 wind turbines, each with a height of approximately 150 meters from sea level to blade tip. The turbines have a rotor diameter of 126 meters and are installed in water depths ranging between 25 and 29 meters.

Total Capacity and Energy Production

The wind farm has a total capacity of 332 megawatts. It is expected to generate more than 1,300 gigawatt-hours of green electricity annually, which is sufficient to power approximately 400,000 German households.

Infrastructure and Grid Connection

• Foundation and Installation: The wind turbines are supported by monopile foundation structures supplied by Ambau Windservice and installed by GeoSea. The MPI Enterprise installation vessel was used for pre-assembling and loading the turbines from the Dutch base port in Eemshaven.
• Substation and Cables: The wind farm includes an offshore substation platform where the power is stepped-up from 33kV to 155kV. The electricity is then transmitted via the Dolwin Beta high-voltage direct current (HVDC) converter station. From there, it is converted from AC to DC and transmitted to the seaward grid connection point at Dörpen-West, where it is converted back to AC and fed into the existing 380 kV electricity grid.

Contractors and Suppliers

• Turbines: Senvion SE, a wholly owned subsidiary of Suzlon, was contracted for the delivery, installation, and commissioning of the wind turbines.
• Cables: Siem Offshore Contractors (SOC) was responsible for the supply and installation of the inner array grid cable system, with JDR sub-contracted for designing and manufacturing the cables.
• Quality Surveillance and Inspection: ABS Group provided quality surveillance and inspection services.
• Other Contractors: Torsten Janssen Architektur and Ingenieurbüro delivered building plans and site supervision services, while Bluestream installed accelerometers and impressed current cathodic protection (ICCP) reference cells.

Financing

The project was financed through a €1.2 billion investment, with a lending group providing €840 million in secured term loans and associated facilities. The financial closure was achieved in March 2015. The European Union also co-funded the project through its NER 300 programme.

Construction and Operational Timeline

• Foundation Installation: The first steel foundation was installed in December 2015.
• Turbine Installation: All 54 turbines were installed by September 2017.
• First Power Generation: The first turbine began generating power in March 2017.
• Commercial Operations: The wind farm began commercial operations in December 2017.

Operation and Maintenance

The wind farm is monitored from the operation and maintenance base in Norddeich, which was inaugurated in September 2016. The base was leased under a 26-year rental agreement from Norddeicher Schiffswerft.

Sustainability and Environmental Considerations

The project is part of Germany’s Energiewende (energy transformation) programme, aimed at increasing offshore wind capacity. The wind farm is designed with sustainability in mind, including habitat conservation, wildlife protection, and continuous monitoring to minimize impacts on marine life. By generating clean, renewable energy, it helps reduce global carbon emissions and promote a healthier environment.