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Sea Link


Sea Link


July 2024 consultation

Since the close of our statutory consultation in December 2023, we have been reviewing all feedback received and carrying out further technical and environmental assessments. 

As a result of this work, we have made some changes to our plans that we want to share with you before we submit our application for development consent early next year. The refinements and changes we are proposing do not substantially alter the project as a whole; our proposals remain largely the same as presented at our consultation last year.

About Sea Link 

National Grid Electricity Transmission is proposing to reinforce the transmission network between Suffolk and Kent via a new, primarily offshore, cable link. 

Sea Link has been designed to increase the capacity of the electricity transmission network, so it can carry more low carbon and renewable energy from where it is generated, to homes and businesses across the country. To do this, we would need to install a 2 gigawatt (GW) high voltage direct current (HVDC) cable between Suffolk and Kent, approximately 138 kilometres (km) long and predominantly offshore. 

To bring the power from the subsea cables into and out of the electricity network in both Suffolk and Kent, we would need to build new onshore infrastructure including converter stations, substations and new underground and overhead electricity lines, as well as upgrading existing overhead electricity lines. 

Power will be able to flow along the Sea Link cables in either direction, depending on where renewable energy is being generated at that time and where in the country power is needed.

Why is this happening?

Sea Link is needed because the existing electricity transmission network does not have enough capacity to reliably transport all the new energy we expect to connect to the network over the next ten years and beyond. 

The network in and between East Anglia and the south-east of England needs reinforcing for four main reasons: 

  1. the existing transmission network was not designed to transport electricity from where we increasingly now generate it (largely offshore) 
  2. the growth in offshore wind, interconnectors and nuclear power means that more electricity will be generated in the years ahead than the current network is able to securely and reliably transport 
  3. as a country, electricity demand is forecasted to at least double by 2050, increasing the amount of energy we need to transport to homes and businesses 
  4. upgrading the existing network as it is today (such as through replacing cables to carry more power) will not be enough to carry the amount of future power whilst operating to required standards. 

Sea Link is just one of several electricity network reinforcements that are needed to ensure the electricity transmission network is fit for the future.

The project programme


Stage 1 (non-statutory) public consultation


Stage 2 (statutory) Consultation


Project update and targeted consultation

Early 2025

Submission of application for development consent


Construction starts

Contact the team

If you have any questions or comments about Sea Link, please get in touch by emailing [email protected], by calling 0808 134 9569 or by writing to Freepost SEA LINK. 

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