Here you’ll find answers to some of the most frequently asked questions about the Sea Link project.

We hope they answer your questions and will update them as our work progresses.

Who is National Grid?

National Grid is a group of companies, and one of those companies, National Grid Electricity Transmission, owns, builds and maintains the network in England and Wales. It is this company that is developing plans for the Sea Link reinforcement.

 Within the National Grid Group there are other distinctly separate legal entities, each with their individual responsibilities and roles. More information about National Grid can be found on the about us section of National Grid’s website.  

What is National Grid Electricity Transmission?

National Grid Electricity Transmission (NGET), owns, builds and maintains the high-voltage electricity transmission network in England and Wales. This network operates primarily at 400,000 volts (400 kV) and 275,000 volts (275 kV).  

It is NGET that is developing plans for the Sea Link reinforcement and is the electricity transmission arm within National Grid.

What is National Grid ESO?

The Electricity System Operator (ESO) is legally separate from the rest of National Grid and ensures that Great Britain has the essential energy it needs by making sure supply meets demand every second of every day.

What is National Grid Ventures?

National Grid Ventures (NGV) operates a mix of energy assets and businesses to help accelerate the development of our clean energy future (such as undersea interconnectors that allow the UK to share energy with other European countries).

What are National Grid’s policies when working in the UK?

National Grid’s commitments when undertaking works in the UK can be found in our stakeholder, community and amenity policy here: commitments when undertaking works in the UK

Why is National Grid reinforcing the transmission network?

The Government’s ten point plan for a green industrial revolution, together with the net zero strategy and the British energy security strategy, is driving unprecedented investment into new renewable and low carbon electricity generation. This includes the target of up to 50 gigawatts (GW) of offshore wind generation by 2030. At the same time, electricity demand is set to increase as other sectors of the economy move away from fossil fuels and increasingly rely on renewable and low carbon electricity. This will put significant pressure on the national electricity transmission system, the network of pylons, substations and cables that takes energy from where it’s generated to where it’s used. The network needs to be reinforced so that electricity continues to flow securely and reliably around the UK. NGET is planning several major reinforcement projects needed to meet this challenge; Sea Link is one of those reinforcements.

What is Sea Link?

Sea Link is an essential upgrade to Britain’s electricity network in East Anglia and Kent using subsea and underground cable. The proposal includes approximately 130km of subsea cables between Sizewell area in East Suffolk and Richborough in Kent. At landfall, the cables would go underground for up to 5 km to a converter station (one at each end). The converter station converts direct current used for the subsea section to alternating current, which our homes and businesses use. A connection is then made to the existing transmission network. In Suffolk, via the proposed Friston substation; in Kent via a direct connection to the overhead line between Richborough and Canterbury.

Why is Sea Link needed in Suffolk and Kent?

We are at the initial development stage of our Sea Link project which seeks to reinforce and strengthen the network between Friston in Suffolk and Richborough in Kent to carry renewable and low carbon power to homes and businesses. We developed much of the existing network in East Anglia and Kent in the 1960s, and does not have sufficient capacity to carry future renewable and low carbon power that’s forecasted to connect to the network – from offshore wind, interconnectors and nuclear power.

We need to upgrade the electricity network to carry this extra power.

Why use high voltage direct current?

Subject to the need of the project, HVDC can be the most efficient way of transporting electricity over long distances. The direction the electricity flows can be controlled, which will become particularly important as we manage intermittent renewable energy.

What is a converter station?

A converter station houses the technology that converts electricity between alternating current (AC) and direct current (DC) and enables it to be transmitted over long distances. AC is used in each country’s transmission system to power homes and businesses, while DC is used for sending electricity long distances.

Why is the converter station being sited within a given distance from the existing network?

Siting the converter station as close to the transmission network as possible reduces the amount of equipment needed to transmit AC electricity. The greater the distance, the greater the cost to consumers and impact on communities and the environment.

How are you coordinating with other projects?


We are exploring options to co-locate Sea Link infrastructure with NGV’s Eurolink and Nautilus projects – project buildings, cable corridors and landfall locations. We are also committed to exploring how we can coordinate our activity with other developers, like ScottishPower Renewables and EDF.


We are also exploring the potential for offshore coordination as part of the Offshore Transmission Network Review (OTNR) ‘Early Opportunities’ workstream. Sea Link, which is a reinforcement of Britain’s UK transmission network, is needed irrespective of offshore coordination. More broadly, significant reinforcement of onshore infrastructure is key to enabling a clean low carbon future.

How are NGET/NGV/SPR/EDF proposing to work together to minimise total construction impact, on both the environment, and on local communities?

We are exploring potential options to co-locate Sea Link infrastructure with NGV’s EuroLink and Nautilus projects – project buildings, cable corridors and landfall locations to reduce impact on communities and the environment. We are also committed to exploring how we can coordinate our construction activity with other developers, like SPR and EDF.

What will be the cumulative effects of all these projects on the East Suffolk communities, and what are you proposing to do to mitigate and compensate for those effects?

We are exploring potential options to co-locate Sea Link infrastructure with NGV’s EuroLink and Nautilus projects – project buildings, cable corridors and landfall locations to reduce impact on communities and the environment. We are also committed to exploring how we can coordinate our construction activity with other developers, like SPR and EDF. National Grid is committed to being a good neighbour and We fund projects run by charities and community groups that meet local community needs by providing a range of social, economic and environmental benefits.

What community benefit are you proposing to offer us?

We believe that business needs to stand for something more than profitability, and we are committed to leaving a lasting positive legacy for the communities in areas where we build and maintain our infrastructure. Our infrastructure projects and daily operations allow us to give back to communities who are impacted by our works through our Community Benefit Plan. The Community Benefit Plan is a framework of activities that show National Grid is listening, is committed to leaving a positive legacy and enabling an equitable future for the communities we serve.  

The Community Benefit Plan is split into four distinct pillars, each comprising several initiatives and schemes. These pillars are: 

  • Grid for nature - Developing green space for local and deprived communities to use and enjoy. Consists of the Woodland Strategy & Great British Bee Project initiatives, several regional/national partnerships, and green leases.  
  • Net Zero Heroes - Forming strong local partnerships with stakeholders close to our projects and through our in-house expertise, to help them realise their own climate ambitions.  
  • Skills/STEM - Seeking regional partnerships with suppliers to part fund the establishment of training centres and flexible training programmes to help give the next generation the skills they need to be part of the Net Zero Energy Workforce. Additionally, we will engage with schools and colleges through site visits, grants, and innovative targeted programmes that are aligned to the curriculum. 
  • Community benefit - Funding community projects that provide social, economic, and environmental benefits to local communities, ensuring we leave behind a positive legacy.  

The initiatives within the NGET Community Benefit Plan are also aligned to National Grid’s Responsible Business Charter, which focuses on five key areas where we can really make a difference: the environment, our communities, our people, the economy and our governance. These focus areas underpin our new strategic priorities and make sure that responsibility is woven through everything we do.  

Will EMF from the Sea Link project affect my health?

Some people worry that Electromagnetic fields (EMFs) may have negative health effects. We take these concerns seriously and want to keep the public, our contractors and employees safe.  We ensure all of our existing and proposed equipment, including those on this project, comply with independent safety guidelines set to protect us all against EMF exposure. After decades of research the weight of evidence is against there being any health risks of EMFs below the guideline limits.

For further information on EMFs visit our website, If you would prefer to talk about your concerns, please do not hesitate to call the EMF helpline on 0845 702 3270 or email [email protected].

How are you going to seek planning permission to build Sea Link?

​NGET has received a Section 35 Direction from the Department for Business, Energy and Industry Strategy (BEIS) that confirms Sea Link should be dealt with as being “nationally significant” and be treated as development for which development consent is required under the Planning Act 2008. The application is made to the Planning Inspectorate, who hold hearings to examine the proposals and make a recommendation to the Secretary of State. The minister will decide on whether a development consent order (DCO) should be granted for the proposed project.  In addition to development consent, a DCO can contain powers for compulsory acquisition of land, the need for which will be considered as part of the examination of the DCO. ​

What is the project timeline?
Sea link timeline
When are National Grid running their non statutory consultation? How and when can I provide feedback?

Sea Link is running an 8-week non statutory consultation from Monday 24 October until Sunday 18 December.

People can speak with National Grid’s teams by attending face to face consultation events, online webinars, visiting the project website and by getting in touch with the project team via their separate freephone numbers and project e-mail addresses.

Paper copies of consultation materials will also be available to view at several locations in the local area, so there is lots of ways to get involved and we hope residents will be able to join us and hear more about what we are proposing and give us their feedback on our plans. ​

Please visit our Consultation page to find out more.

What can I influence?

We are undertaking our non-statutory consultation to seek you feedback on our proposed converter station site locations, cable corridors, landfall sites and marine cable corridor, or any views or local information that you would like us to take into account.

All feedback we receive will be carefully considered as we refine our proposals ahead of our statutory consultation in 2023.

Why is Sea Link being proposed to connect in Suffolk?

Government policy is driving a sizeable shift towards low carbon and renewable generation. Significant amounts of this new generation is planned along the east coast in this decade including a 4 fold increase in offshore wind from 11 GW today to up to 50 GW by 2030.

We need to facilitate the export of increased power out of East Anglia. The existing transmission network was not designed and built with the envisaged amount of power in mind and therefore it needs to be reinforced.

National Grid is proposing several network reinforcement projects of which Sea Link is one.

Sea Link is proposed to connect into the proposed Friston substation as this part of the network has a concentration of planned generation and connecting Sea Link here offers additional consumer benefit as it is able to carry an additional 2 GW out of the area should system conditions need it to.

Why is Sea Link not connecting to Bradwell?

Connection at Bradwell would not meet the identified need to reinforce the network in East Anglia.

Why is Sea Link not connecting to Bramford?

Connection at Bramford would be less economic and efficient than a connection at Friston.

Why have you not considered brownfield sites and/or other national grid substations?

We have been unable to find any brownfield sites within the Converter Station Option Area that are suitable for the infrastructure proposed. All existing National Grid substations in the area are already at capacity or do not have the space around them to allow the connection required by this project.

What does coordination with EuroLink and Nautilus mean?

In response to stakeholder feedback, NGET’s Sea Link project and NGV’s EuroLink and Nautilus projects are exploring potential opportunities to coordinate.

Coordination could range from co-location of infrastructure from different projects on the same site, to coordinating construction activities to reduce potential impacts on local communities and the environment.

How can I find out more information about EuroLink and Nautilus?
If you collocate 3 converter stations together how big a footprint would that take up? How many football pitches is that?

Each Converter Station will be approximately 6 hectares, therefore a site for 3 converters would cover around 18 hectares.

1 Hectare is approximately 1.2 to 1.6 football pitches therefore the whole site will cover approximately 28 football pitches.

Why is Sea Link being connected in Kent? Why at Richborough?

During periods of high wind generation from offshore wind farms on the east coast, electricity will need to be exported to Europe via interconnectors to balance the electricity network. Many of these interconnectors are located along the south east coast of the UK.

In the future there will be insufficient network capacity in the region to get power into the UK network to and from the South East Coast when interconnectors are importing and exporting. Sea Link will provide the additional network capacity needed to enable the import and export of wind energy to and from Europe.

Sea Link

Contact us

Please get in touch if you have any questions or comments on the Sea Link development.

Call our Community Helpline: 0808 134 9569 (lines are open Monday to Friday 9am – 5.30pm)

Email us: [email protected]

Write to us: FREEPOST SEA LINK (no stamp or further address details are required)