The Vesterhav Nord and Syd project involves the construction of the Vesterhav Nord and Vesterhav Syd offshore wind farms in the Danish waters of the North Sea.
Developed by Swedish energy company Vattenfall, the two wind farms will have a combined capacity of 344MW. The project is expected to generate 1.57TWh of green power a year, which will be sufficient to meet the energy needs of 380,000 households in Denmark.
The wind farms are expected to increase the country’s wind power generation capacity by more than 10% after commissioning, which is scheduled for the end of 2023.
The permit to commence construction of the project was awarded by the national energy regulator Danish Energy Agency in December 2020.
The final investment decision (FID) on the project was made in December 2021. The offshore construction work of the two wind farms is expected to begin in mid-2022.
Vesterhav Nord and Syd location
Vesterhav Nord will be located between 5.5km and 8.4km off the West Jutland coast at Harboøre. Vesterhav Syd will be located between 4km and 10km off the coast of Ringkøbing Fjord.
Vesterhav Nord and Syd make-up
The Vesterhav Nord and Vesterhav Syd wind farms will have an installed capacity of 176MW and 168MW, respectively.
The project will be powered by 41 Siemens Gamesa’s SG 8.0-167 DD turbines, 21 for Vesterhav Nord and 20 for Vesterhav Syd. Each direct drive (DD) turbine will have a power generating capacity of 8.4MW.
The nacelle height of each turbine is expected to be 109m, while the height of the wingtip is expected to reach up to 193m. The rotor diameter of the turbines is 167m, while the swept area of each turbine is 21,900m² (235,729.64ft²). The length of each blade is 81.4m.
The wind turbines will be installed on monopile foundations, topped by transition pieces, at water depths of up to 20m.
Weighing up to 260t, each transition piece will help connect the wind turbine to the monopile foundation.
The turbines of Vesterhav Nord will be installed 710.5m away from each other, while the distance between the turbines at the Vesterhav Syd wind farm will be 685m.
The two wind farms will be serviced from the Port of Hvide Sande on Denmark’s western coast.
Grid connection for Vesterhav Nord and Syd
The power generated from the two offshore wind farms will be transmitted onshore by 60kV cables. The power from Vesterhav Nord will be collected at an onshore substation, and the electricity is then planned to be transmitted to the high-voltage substation at Idomlund, where it will feed the Danish grid.
The grid connection for Vesterhav Syd is expected to involve an onshore collection point near the coast. The electricity will then be transferred to a high-voltage substation at Stovtrup using a 150kV cable.
The electricity transmission network will be operated by Energinet, the Danish national transmission system operator.
Siemens Gamesa Renewable Energy (SGRE) was selected to supply its turbines for the Vesterhav Nord and Syd wind farms in November 2017.
Vattenfall engaged EEW Special Pipe Constructions to fabricate 41 monopiles for the Vesterhav project in November 2021.
Bladt Industries was contracted for the manufacture and supply of 41 transition pieces for the two wind farms. The transition pieces are expected to be delivered at the beginning of 2023.
Jan De Nul Group, an engineering company based in Belgium, was chosen for the transportation and installation of the project’s 41 turbines. The company will deploy its Vole au vent jack-up installation vessel to complete the work.
Vattenfall selected German company TÜV SÜD to provide certification for the two wind farms across different phases, including design, manufacturing, transportation, installation and commissioning.
Hellenic Cables received a contract to design, manufacture, test and supply approximately 70km of 66kV cross-linked polyethylene (XLPE) insulated inter-array cables and associated accessories for the Vesterhav project in August 2021. The cables are expected to be delivered in the first quarter (Q1) of 2023.
Engineering solutions company EDS HV Group was engaged to provide high-voltage network commissioning and safety management for the two wind farms. The contractual scope also includes full management of all senior authorised persons on-site.
Greece-based company Asso.subsea was contracted to transport, install, protect and commission 70km of 66kV export and inter-array submarine cables, including four export and 37 inter-array cables.
The 2020 environmental impact assessment report for the project was prepared by Orbicon, a Danish engineering consulting firm acquired by multi-national company WSP in 2019.