World’s largest interconnector begins operating

The Viking Link electricity interconnector between the UK and Denmark has commenced operations, now transporting power between the two countries.

Deemed the world’s longest land and subsea interconnector, the £1.7 billion Viking Link started commercial operations on December 29, 2023. 

The link has a capacity of 1.4 GW and stretches for 475 miles under land and sea to join the Bicker Fen substation in Lincolnshire, UK, with the Revsing substation in southern Jutland, Denmark. 

Initially, the interconnector will be operating at a capacity of 800 MW before increasing over time to 1.4 GW. The UK’s National Grid and Danish transmission system operator (TSO) Energinet will be working together to bring the asset up to full capacity over the coming year. 

In its first year of operation, Viking Link is expected to save approximately 600,000 tonnes of carbon emissions, equivalent to taking roughly 280,000 cars off the road.

“This record-breaking new link is a fantastic example of engineering and collaboration with our partner, Energinet,” said President of National Grid Ventures Katie Jackson.

“As we deploy more wind power to meet our climate and energy security targets, connections to our neighbouring countries will play a vital role increasing security of supply and reducing prices for consumers. Stretching further across land and sea than any of our existing links, it connects the UK to clean, green Danish energy, improving security of supply and bringing huge carbon and cost savings for UK consumers.”

Construction on Viking Link started in 2019, with more than four million working hours spent to get to this point. 

Principal contractor Siemens Energy built the converter station in the UK while Energinet built the Danish converter station. Siemens Energy designed, installed and commissioned the electrical assets on both sides.

The HVDC offshore cable was manufactured and laid by Prysmian. The cable was laid on the seabed using the Leonardo Da Vinci vessel, which was then buried using Asso trenches. Prysmian manufactured the HVDC land cable in the UK which was installed by Balfour Beatty, and the Danish land section was manufactured by NKT and installed by Monck. 

National Grid launched the UK’s first interconnector (IFA) to France in 1986. Since then, it has built five more including a second link with France (IFA2) and further connections with the Netherlands (BritNed), Belgium (Nemo Link) and Norway (North Sea Link).

Between 2020 and 2030, National Grid expects its interconnectors will have helped the UK to avoid around 100 million tonnes of carbon emissions and by 2030, 90% of the energy imported through the company’s interconnectors will be from zero-carbon energy sources.

Earlier in 2023, National Grid announced joint plans with TenneT for a new 1.8 GW interconnector between the UK and the Netherlands called LionLink. LionLink would be the second link between the two countries and is expected to be operational in the early 2030s. A second new link called Nautilus, is also in the planning phase with the potential to connect with Belgium.