The British and Danish electricity grids have been physically connected for the first time, following the completion on 19 July of cable works on the Viking Link 1400 MW HVDC interconnector.
The final section of the state-of-art-high voltage subsea cable, which joins Bicker Fen in Lincolnshire with Jutland in Denmark, was completed offshore in the North Sea by Prysmian’s cable laying vessel 'Leonardo da Vinci' and its team.
The £1.7 billion (€2 billion) project is a joint venture of National Grid and Danish system operator Energinet. It will be the world’s longest land and subsea interconnector – stretching for 475 miles (765 km) between the two countries. Due to be operational by the end of the year, it will enable the sharing of enough green electricity to power 1.4 million UK homes.
The complex cable joining process took place in Danish waters and took several days to complete. It involved lifting the sections of cables out of the water and joining each conductor/strand together on the cable laying vessel.
Viking Link is National Grid’s sixth interconnector. The company already has five operational cables joining the UK with France (IFA and IFA2), The Netherlands (BritNed), Belgium (Nemo Link) and Norway (North Sea Link).
Rebecca Sedler, MD for National Grid Interconnectors, said: “This is a fantastic moment for the UK and Denmark, and a key milestone for the world record project, as we join the electricity networks of our two countries for the first time. After years of planning and construction work, [this] announcement is testament to the hard work and dedication of our team and our partners on both sides of the connection.
“As countries begin to integrate more offshore wind generation into their energy systems, interconnectors will become critical for transporting clean and green energy and helping to manage the intermittent nature of renewable sources.”
Construction on Viking Link started in 2019 and so far, more than three million working hours have been spent on planning and construction. The HVDC cable, manufactured and laid by Prysmian and NKT, is made from copper, steel, paper and plastic and is buried on the seabed.
National Grid expects its interconnectors will have helped the UK to avoid around 100 million tonnes of carbon emissions between 2020 and 2030, and by 2030, 90% of the energy imported through the company’s interconnectors will be from zero carbon energy sources.
Earlier this year National Grid announced plans for a 1.8 GW Offshore Hybrid Asset (combined offshore generation and transmission asset) between the UK and the Netherlands, called LionLink. A second OHA called Nautilus is also in the planning phase, with the potential to connect with Belgium.
Offshore Hybrid Assets are said to be the next phase of interconnection, joining two countries together and also connecting with offshore wind generation. OHAs support UK and EU efforts – they have the potential to meet 2030 and 2050 offshore wind targets, speed up the displacement of fossil fuelled power stations and, crucially, have the potential to reduce the impact on the environment and coastal communities with fewer individual connections.
Image courtesy of National Grid