Nemo Link

In its first five years Nemo Link moved 29 TWh of electricity, 24.75 TWh of it towards the UK and 4.25 TWh towards Belgium, with availability above 99%. Those figures, quoted in the Nemo Link article, say two things at once: the cable almost never failed, and about 85% of what it carried went west to Britain.

It was the first electrical connection between the two countries. The cable comes ashore at Pegwell Bay in Kent and runs to a converter station at Richborough. On the Belgian side it lands on Zeebrugge beach and connects at Herdersbrug, near Bruges. Of the 140 km route, 130 km is under water.

The main contracts, worth about €500 million in total, were awarded in 2015: Siemens for the converter stations and J-Power Systems for the cable. DeepOcean laid the cable in 2017 and 2018, and the link became fully operational on 31 January 2019. The official opening had come earlier, on 5 December 2018 at Herdersbrug. The European Commission had designated Nemo a Project of Common Interest, and the site crews passed one million working hours without an injury in September 2017, an achievement that earned the project a Sword of Honour safety award that year. Siemens describes its HVDC Plus voltage-source scheme at ±400 kV, with converter stations at both ends.

Nemo Link is a joint venture between National Grid and Elia, the Belgian grid operator. On the evidence of those five years, it works mainly as an import route for Britain; the reverse flow is real but small.

If you compare it with the older Dutch link BritNed, Nemo is shorter and uses the newer converter technology explained in the HVDC section. Its annual capacity works out at 8.76 TWh, so the five-year total of 29 TWh means the cable ran at roughly two-thirds of its theoretical maximum.