The UK government has granted development consent for the Sea Link project, a £3 billion, 138-km transmission scheme linking Kent and Suffolk. The project aims to boost east-west electricity flow and is slated for construction in early 2027. This development marks a significant milestone for the Sea Link project, which will play a crucial role in the UK's energy infrastructure.
The Sea Link project involves the installation of about 122 km of subsea high-voltage direct current (HVDC) cables across the southern North Sea and Thames Estuary. The cables will link converter stations near Minster in Kent and near Saxmundham in Suffolk. Additionally, the project includes onshore works such as a new converter station at Minster, a new substation beside it, and the removal of existing overhead lines.
In Suffolk, the cable will land north of Aldeburgh and connect to a converter station near Saxmundham via underground HVDC and high-voltage alternating current (HVAC) cables. The project also involves the construction of a new Kiln Lane substation near Friston. National Grid Electricity Transmission has appointed Siemens Energy to deliver the converter stations and associated substation works.
Sumitomo Electric will supply and install the cable system, manufacturing the subsea cables at its £350 million Port of Nigg facility in Scotland. Marine contractor Van Oord will partner with Sumitomo Electric on subsea cable delivery, handling offshore installation duties. The project is expected to create more than 200 skilled jobs at the Scottish cable factory.
Construction of the Sea Link project is expected to start in early 2027, with a target completion date of 2031. National Grid has not yet released a detailed timetable for individual work packages. The project is part of the wider Great Grid Upgrade programme, aimed at expanding transmission capacity, easing renewable energy bottlenecks, and improving overall energy security across Britain.
National Grid submitted a cost estimate of £3.2 billion to Ofgem, but the regulator has proposed funding of about £2.9 billion, with a final decision still pending. The Sea Link project also includes community benefit funds of over £1 million for each of the two counties. This funding will support local communities and ensure that the project benefits the regions it affects.
The Sea Link project is a significant investment in the UK's energy infrastructure, and its completion is expected to have a positive impact on the country's energy security and renewable energy capacity. The project will enhance the transmission capacity between Kent and Suffolk, supporting the integration of renewable energy sources and reducing energy bottlenecks.
Key points
- The UK government has granted development consent for the £3 billion Sea Link project.
- The project involves the installation of 122 km of subsea HVDC cables across the southern North Sea and Thames Estuary.
- Construction is expected to start in early 2027, with a target completion date of 2031.
