Nemo is open for business

THE Nemo Link is an HVDC submarine power cable between Richborough Energy Park in Kent, in the United Kingdom, and Zeebrugge, in Belgium. It has been built by Nemo Link, a joint venture of the UK’s National Grid and the Belgian TSO Elia. The £600 million interconnector is the first between the two countries, capable of transmitting up to 1000 MW at 400 kV, in either direction, for an annual transmission capacity of 8.76 TWh, and is expected to add flexibility to both countries’ energy systems. The link was formally inaugurated in early December 2018, and underwent testing and commissioning in December and January. On 31 January 2019 it became fully operational.

The European Commission has designated it a Project of Common Interest as it contributes to an integrated European energy market.

The total cable length is 140 km of which 130 km is submarine, buried at a depth of up to 60 metres. The offshore section runs from Pegwell Bay in the UK to Zeebrugge beach in Belgium where it meets an onshore cable nearly 9 km long that connects the landing point to the converter station in Herdersbrug. In the United Kingdom there is 2 km of cable overland from Pegwell Bay to the Richborough converter station.

Benefits

John Pettigrew, CEO of National Grid, commented: “Nemo Link will bring great benefits to consumers in the UK and Belgium by offering both countries access to a broader energy mix and providing opportunities to expand into other electricity markets.

“This new connection will also provide significant social benefits. By connecting the UK and Belgian electricity markets, we will ensure customers have access to different sources of generation and lower priced electricity.

“Over the next five years National Grid will be investing more than £2 billion in new interconnectors to Europe and our significant commitment is driven by the value that interconnectors like the Nemo link can bring to customers at both ends of the cable.”

On 30 January capacity on the interconnector became available to purchase via the implicit day ahead auction, for delivery on 31st January. This followed a successful testing period during which active power transfers had been taking place between Belgium and the UK.

Construction

In 2015, contracts totalling €500 million were awarded to Siemens for the construction of the two onshore HVDC converter stations and to J-Power Systems Corp for the cable system. The contract for the laying of the cable was awarded to DeepOcean which carried out the work in 2017 and 2018. The HVDC cable was supplied by Sumitomo Electric.

Siemens supplied and installed the converter stations and all associated equipment including the supply and installation of its HVDC Plus technology. HVDC Plus is a controllable and flexible system and is said to bring operational benefits to both transmission systems. Each of the two converter stations is transmitting 1000 MW of power at a transmission voltage of ±400 kV DC.

Third interconnector

Nemo Link is National Grid’s third interconnector to Europe following the success of the 2000 MW IFA connecting the UK to France, and the 1000 MW BritNed cable, UK to The Netherlands. The 1400 MW Viking cable UK-Denmark came on line in January and the company has two more under construction, North Sea Link which will connect the UK and Norway and IFA 2 which will provide a second link to France. These will add 1400 and 1000MW of capacity respectively.

In February Nemo Link held a two day conference to allow prospective customers to become familiar with the auction process, which will get underway in April.

Explosive connection

During the construction of the link divers found more than 1200 unexploded ordnance, including mines and WW2 bombs. More than 30 of these were detonated by Royal Navy divers.

Finds also included a 17th-century cannon off the UK coast, loaded and ready for battle.