September 2024 - OCSS joint statement
National Grid Electricity Transmission (Sea Link), North Falls (Offshore Wind Farm) and Five Estuaries (Offshore Wind Farm) have been working together to explore the potential for offshore coordination as part of the Offshore Transmission Network Review (OTNR) “Early Opportunities” workstream. The projects, acting together in a consortium led by North Falls, were awarded funding by the Department of Energy Security and Net Zero (DESNZ) through the Offshore Coordination Support Scheme (OCSS) in December 2023.
On 28 March 2024, the consortium submitted a high-level feasibility study that formed the first step of the grant funding agreement. The study assessed the feasibility of a coordinated offshore connection specifically: the capital costs; building blocks; construction and commissioning methodologies and overall programme associated with a coordinated solution.
The Secretary of State for Energy Security and Net Zero has reviewed this study, amongst other information and has decided not to grant further funding to the consortium. The feasibility study identified that coordination is technically feasible however, it also identified:
- an increase in capital costs of up to £890m
- constraint costs associated with an outage on Sea Link of over £500m*
- a programme delay for North Falls and Five Estuaries of up to five years
Given the significant extra costs and the negative impact on the delivery timeline of connecting more renewables to the UK energy system, especially considering the government's commitment to quadruple offshore wind and fully decarbonise the UK's electricity system by 2030, the consortium supports the Secretary of State’s decision and will not be further pursuing a coordinated offshore connection. We would like to thank DESNZ for its continued engagement throughout the grant term.
*This figure is attributed to the constraint costs associated with an outage on Sea Link in 2032/33 only.
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:
- the existing transmission network was not designed to transport electricity from where we increasingly now generate it (largely offshore)
- 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
- 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
- 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
Oct - Dec 2022
Non-statutory public consultation
Oct - Dec 2023
Statutory Consultation
July - Aug 2024
Project update and targeted consultation
Early 2025
Submission of application for development consent
2026-2030
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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