North Sea, Germany
Start of Operations
Northland Power and RWE Innogy
The 332MW Nordsee One offshore wind project is located on German territorial waters in the North Sea. Northland Power (85%) and RWE Innogy (15%) own the windfarm.
The first steel foundation for the windfarm was successfully installed ahead of schedule in December 2015. All the wind turbines were installed by September 2017 and the commercial operations began in December 2017.
The project is expected to generate more than 1,300GWh of green power a year, sufficient to power 400,000 German households.
The development of Nordsee One forms part of Germany’s Energiewende (energy transformation) programme, which is aimed at achieving 6,500MW of installed offshore wind capacity by 2020 and 15GW by 2030.
Nordsee One windfarm location and make-up
The Nordsee One windfarm site is situated approximately 40km north of the Juist Island, among the Terschelling-German Bight and German Bight Western Approach traffic separation scheme (TSS). It extends across approximately 41km² of space within a special spatial planning area reserved for offshore wind energy projects.
The location offers shallow water and high wind speeds, which are ideal considerations for setting up an offshore windfarm.
The windfarm encompasses 54 Senvion 6.2M126 wind turbines and an offshore substation platform. Each wind turbine is approximately 150m tall from sea level to blade tip.
The 6.2M126 is the advanced variant of the proven 5M model. Each turbine, with a rotor diameter of 126m, is installed in water depths ranging between 25m and 29m and is inter-connected by inter-array cables with a total length of up to 70km.
MPI Enterprise installation vessel was used for pre-assembling and loading of the wind turbines from the Dutch base port in Eemshaven to Nordsee One project location.
The windfarm is being monitored from the operation and maintenance base in Norddeich, which was inaugurated in September 2016. The base was leased by Nordsee One from Norddeicher Schiffswerft under a 26-year rental agreement.
Grid connection for Nordsee One windfarm
The power produced by the turbine generators is stepped-up from 33kV to 155kV in the Nordsee One offshore substation, and linked to the Dolwin Beta high-voltage direct current converter station where the electricity is converted from AC to DC.
The converter station then transmits the power to the seaward grid connection point at Dörpen-West, which converts the DC into AC for feeding into the nearest grid access point at Hagermarsch.
Financing for Nordsee One offshore wind project
ABN AMRO, Bank of Montreal, Commerzbank, Export Development Canada, Helaba, KfW IPEX, National Bank of Canada, Natixis, Rabobank, and The Bank of Tokyo-Mitsubishi provided funding for the €1.2bn project.
The lending group provided €840m secured term loan and associated loan facilities which funded approximately 70% of the project costs. The financial closure for the project was achieved in March 2015.
European Union co-funded the wind project through its NER 300 programme.
Contractors involved in the offshore wind project
Senvion SE, a wholly owned subsidiary of Suzlon, was awarded a contract for the delivery, installation and commissioning of 54 wind turbines for the windfarm, in December 2014.
Siem Offshore Contractors (SOC) was awarded a turnkey contract for the supply and installation of the inner array grid cable system for the wind project in April 2014. JDR was sub-contracted by SOC to design and manufacture cables for the windfarm.
JDR is responsible for the supply of complete package, including more than 70km of aluminium conductor cable and associated accessories, as well as post-supply offshore pre-commissioning services.
ABS Group was contracted in April 2015 for the delivery of quality surveillance and inspection services in multiple manufacturing locations and offshore during the construction phases of the windfarm.
Ambau Windservice was contracted to supply monopile foundation structures for the windfarm, while GeoSea is responsible for the installation of the monopiles.
Torsten Janssen Architektur and Ingenieurbüro was selected to deliver the building plan and site supervision services for the project.
Bluestream installed accelerometers and impressed current cathodic protection (ICCP) reference cells in five foundation monopiles using a remote-operated vehicle (ROV), under a contract awarded in February 2017.