Van Oord, a Netherlands-based maritime contracting company, has completed installing and burying inter-array cables at CrossWind’s Hollandse Kust Noord offshore wind farm, bringing it closer to being fully operational by the end of this year.
Van Oord’s top duo cable-laying vessel Nexus and trencher Dig-It (a remotely-operated vehicle operated from the vessel Subsea Viking) have installed a web of 69 inter-array cables measuring 87 miles in total. The offshore wind farm is located 11.5 miles off the coast of the Netherlands, near the seaside resort of Egmond aan Zee.
Van Oord designed a 66 kV inter-array grid for the Hollandse Kust Noord offshore wind farm to guarantee reliable and safe transmission of the generated electricity. Dutch manufacturer TKF (Twentsche Kabelfabriek) supplied the cables. Nexus, equipped with a 5,500-ton capacity cable carousel, installed the inter-array cables. Trencher Dig-It then buried the cables to the required depth of between 3.3 and 5 feet. The Dig-It, a tracked remotely operated vehicle, can be used for burying cables both in jetting mode for sandy soils and in chain-cutter mode for harder soils. At the Hollandse Kust Noord project, both modes were used successfully.
Wind farm developer CrossWind, a joint venture between Shell and Eneco, contracted Van Oord for the design, engineering, procurement and transport and installation of the wind turbine foundations, inter-array cables, as well as the transport and installation of the wind turbines themselves. Earlier this year, Van Oord completed all 70 monopile foundations. Currently, Van Oord is deploying two offshore vessels to install the wind turbine generators and is also performing the electrical termination works of the cables in the generators.
While under construction, the Hollandse Kust Noord offshore wind farm already produced its first MWh of green electricity and delivered it to the Dutch mainland. In coming months, production capacity will be continuously increased. Once complete, the project will have a total installed capacity of 759 MW, generating at least 3.3 TWh per year, which is enough renewable electricity to meet the power demand of more than one million Dutch households.