Electrical Review to examine Britain's growing reliance on subsea electricity cables

Electrical Review is set to host its next virtual Briefing on November 25, where we will examine whether Britain is truly prepared to rely on an expanding subsea electricity network. 

The event, which is sponsored by Black & Veatch, comes as the UK plans major investment in offshore transmission infrastructure. In June, the National Energy System Operator (NESO) recommended three times as much new offshore subsea cabling as new onshore infrastructure as part of its plans for the electricity network during the 2030s.

Projects such as Eastern Green Link 3, which will include approximately 580km of subsea cable between Scotland and England, demonstrate the scale of the infrastructure being planned.

These links could help ease congestion on the existing electricity network by moving power from where it is generated to where it is needed, but it comes with a catch – building more infrastructure beneath the sea can create challenges when something goes wrong.

Unlike overhead power lines, damaged subsea cables can be difficult to access, with repairs potentially requiring specialist vessels, replacement cable and lengthy periods of reduced availability.

We can already point to existing examples – with a defective subsea export cable at the Gwynt y Môr offshore wind farm resulting in reduced transmission service between January and August 2025. That’s a long time – with Ofgem blaming the delayed repair due to the lack of sufficient replacement cable being available.

That’s not the only problem, however. Given the growing spotlight on attacks on undersea infrastructure by hostile foreign powers in recent years, there are concerns about how we better protect that infrastructure. Earlier this month, the UK Government proposed tougher penalties for damaging critical undersea infrastructure, but whether that will actually deter hostile actors remains to be seen. 

This upcoming Briefing is an ideal opportunity to explore these issues, with a wide range of viewpoints set to take part – including those building the networks and those supplying the equipment and engineering know-how that is vital to Britain’s modern electrical grid. 

You can register for this upcoming briefing, dubbed Can Britain build a subsea grid it can rely on?, by clicking this link. The event is set to take place on November 25 at 09:30 GMT.