Blog: World Ocean Day

By Chris Travers

Every day we work to ensure a resilient and reliable electricity supply to our customers – but did you know that some of this electricity travels miles under the sea before it reaches your home?

The seas and oceans surrounding the UK offer us one of the most efficient and cost-effective ways of transporting large volumes of power every day via subsea cables.

Already we, alongside our partners National Grid Electricity Transmission, operate the Western Link, an 425km high voltage, direct current (HVDC) link from Hunterston in Scotland to Connah’s Quay in Wales. Some 385km of the cable runs under the Irish sea, transporting enough electricity to power over 2 million homes each year.

Together, we are developing two further subsea cables, Eastern Green Link 1 and Eastern Green Link 4, to form part of a subsea electricity superhighway down the east coast of the country.

The transformational links will help boost the UK’s transmission system, enabling more renewables to connect into the grid and ensuring that green electricity can be transported on to homes and businesses across the country.

But before the construction of these projects can begin a huge amount of work is carried out to understand the areas we will be working in and how we can minimise any impact we may have.

Work to determine the cable route for the Eastern Green Link 1 began years ago and the route that will be used is one of over 33 that was carefully considered by our teams. All of these routes examined a number of design factors and policies from biodiversity to societal and economic regulations.

In deciding on the marine route, a comprehensive environmental impact assessment was undertaken covering marine mammals, ornithology, marine archaeology, fish and shellfish, benthic ecology, shipping, commercial fishers, and other sea users. We follow robust processes to manage our work to deliver the subsea cables whilst ensuring the underwater environment continues to be a place where animals such as minke whale – seasonal visitor to our waters – and their food sources continue to visit and live.

Alongside protecting and enhancing the environment for marine life, we also conduct numerous studies and surveys to give us a better understanding of where there may be unexploded ordinance (UXO) within the waters and how best to plan for this on our preferred route. Before construction begins on the project further survey work and targeted investigations for UXO will be carried out.

And, when the cable does begin to be installed, we have opted to use a ‘bundled’ solution where both the cables making up the link will be wrapped together. This means less space will be taken up by the cable on the seabed and fewer vessels will be required for installation.

The installation method will use a simultaneous lay and burial method which helps reduce the exposure of the cable during the process and means we are again able to minimise the number of vessels utilised for the installation.

We have a proven track record of delivering electricity infrastructure to the highest standard in strict accordance with social and environmental regulations and we look forward to delivering Eastern Green Link 1 and the benefits it will bring to help the UK on its journey to Net Zero.