North Sea Link passes halfway line in Norway

Construction of the longest subsea power cable in the world has now passed the halfway point.

The North Sea Link, a joint venture project between National Grid and Norwegian system operator Statnett, is a subsea electricity cable that will connect the UK and Norwegian electricity grids.

Prior to cable-laying in Norway, the team had to maneuver the cable through a lake, inaccessible by a cable layer.

Instead, the team have transported materials piece by piece to build their own custom-made floating platform.

The construction of the platform had an average of 25 people working on it over the course of 11 days.

This operation in Suldalsvatnet, marks the start of the cable laying on the Norwegian side.

The laying of the 2.8-kilometre parallel subsea cables took place from a 43 x 15-metre platform at up to 210 metres depths.

The cable-laying equipment landed on the platform, and within 12 hours, it loaded 150 tonnes of cable on board.

The platform held all the necessary equipment usually found on offshore cable laying vessels.

Nigel Williams, construction director for National Grid North Sea link said,

“The engineering that has taken place to lay high-voltage cables below the seabed is remarkable.

“The difficult terrain, the depth of the waters, and all in amidst of operating during a pandemic has made it extremely challenging.

“Nevertheless, we have powered through and remained on track with our project timelines.”

Up next is to lay the cable out from the fjords in Suldal to the North Sea this summer.

This work will be carried out throughout the remainder of the year.

By 2021 the two parallel 720-kilometre cables between Cambois, Northumberland in the UK and Kvilldal, in Norway will have been completed.

This will make the 1.4-gigawatt North Sea Link the longest subsea power cable interconnector in the world.

It should also be operational by 2021, allowing the UK enough clean energy to power up to 1.4 million homes.