Viking Link: the world’s longest interconnector

The scope of this vast project includes the entire 1,400 km of cabling, of which 1250 km for the submarine route and the rest for the land cables on the UK side. The contract from National Grid Viking Link Limited and Energinet includes the turnkey design, manufacturing and installation of the world’s longest interconnector. It will connect Bicker Fen substation in Lincolnshire, Great Britain and the Revsing substation in South Jutland, Denmark.

The High Voltage Direct Current (HVDC) interconnector will operate at ± 525 kV DC. The aim is to increase access to renewable and sustainable energy sources for over 1.4 million households, potentially reduce the cost of electricity and increase system reliability. Once completed, the connection will improve energy supply security in Denmark and Great Britain by enabling imports from neighbouring interconnected markets.

A project on this scale brings quite a few challenges, especially with regard to manufacturing and rolling out the required cable quantities as well as project management. Keeping to a tight schedule and thinking ahead will remain essential throughout the project. The agreement was signed in August 2019 and commissioning of the project, with a value close to €700 million, is scheduled for December 2023. However, Prysmian had already began organizing all activities well in advance, so that work could commence immediately after signing. A complete team of experts was in place and manufacturing started right away. All cables will be manufactured at the Group’s centre of excellence in Arco Felice (Italy) – and the production has been kicked off in September 2019, right after the signing of the contract.

“We have maintained our production running as per plan, in spite of the COVID-19 complications,” explains Fabrizio Traversi, Project Director, Prysmian Group. “The first cable was successfully tested at the end of May 2020 (Factory Acceptance Tests). This is the first section of cable lengths which will be delivered in the next 3 years. The manufacturing of cable is a very critical part of the entire project, as even the slightest hiccup can result in delays that build up along the line. We’ve invested in expanding our Arco Felice factory, which is a worldwide centre of excellence for the production of paper-insulated cable.”

Fabrizio Traversi

Project Director, Prysmian Group

The central part of the route is relatively far from coast, hundreds of kilometres from the nearest port. The cables cross through 4 Exclusive Economic Zones in Dutch, German, Danish and British waters. Each territory has its own legislation and stakeholders. The cabling crosses more than 40 other lines, such as gas and electricity connections. Each of these aspects requires dedicated activity and dialogue to get approval. 

“Considering the complexity of the Viking Link Interconnector, HSE and Quality are two fundamental pillars of this project: we are committed to deliver the project in quality, with the target of zero incidents. Our internationally recognized cable-making skills and project management attitude coupled with extra strict checks in manufacturing, a great core team and support from hundreds of people in the factories will allow us to succeed!”



This is the first outing for Leonardo da Vinci, Prysmian’s new €170 million cutting-edge installation vessel. This is the world’s most advanced cable-laying vessel, and with 2 rotating platforms of 7,000 and 10,000 tons - the highest carousel capacity in the market. can store and install longer lengths of cable, thus requiring fewer joints and installation campaigns and significantly improving the overall project efficiency.

  • Length: 170 m 
  • Breadth: 34 m 
  • Deep water installation capabilities for depths of more than 3,000 m. 
  • The capstan capacity of up to 100 tons is double the industry average.
  • Bollard pull of about 200 tons, more than double that of the Giulio Verne, it has the highest pulling/towing capacity in its class.
  • Performs complex installation operations with variety of burial systems and tools 
  • Equipped with state-of-the-art DP3 positioning and seakeeping systems. 
  • Specially designed engine and propulsion setup reduces environmental footprint.