Van Oord’s underwater robot Deep Dig-It has started work on the third of four export cables for the 1500MW Hollandse Kust Zuid offshore wind farm off the Netherlands.
Transmission system operator TenneT said the robot had crossed the busy Rotterdam Maasmond with the third cable and is on its way to the recently installed Beta jacket in the Hollandse Kust Zuid wind area.
A consortium of Van Oord and Hellenic Cables is installing the two cables to the Beta platform.
The first two cables were installed in September 2020.
TenneT said the cables will be sunk 5.5 metres into the seabed to cross the Rotterdam Maasmond for the first 10km of the offshore cable route.
In total, 34km of wiring will be installed.
Deep Dig-It is a tracked remotely operated vehicle that travels on the seabed unmanned, making a deep trench for the cables by liquefying the seabed.
At the same time, this underwater trencher lays the cables in the trench and closes it, TenneT said.
The topside and transformer station will be lifted onto the Alpha jacket at the end of the year, while the topside of the Beta jacket is expected to follow early next year.
Once the platforms have been lifted onto the jacket, the last systems will be connected, tested and put into operation.
They will then be connected to the high voltage substation on land and the wind farm is expected to be fully operational in 2023.