The United Kingdom has authorized Sea Link, a 2 GW HVDC link that will connect Kent and Suffolk via 140 kilometers of submarine cable.
He Government of the United Kingdom has authorized the development of Sea Link, a new 2 GW underwater power transmission line will link the counties of Kent and Suffolk. The project, promoted by National Grid Electricity Transmission (NGET), it includes the installation of a 525 kV high-voltage direct current (HVDC) cable approximately 140 kilometers long.
The infrastructure is part of the Great Grid Upgrade program, through which the country seeks to expand its electricity transmission capacity and facilitate the connection of new renewable energy sources. According to current plans, construction will begin in early 2027.
Sea Link will feature a 525 kV submarine cable
The connection will have converter stations in Suffolk and Kent, linked by a cable that will run approximately 140 kilometers across the North Sea and the Thames estuary.
With a transmission capacity of 2 GW, Sea Link will be able to transport enough electricity to power approximately two million homes. Its function will be to facilitate the transfer of energy from generation areas to major consumption centers.
Furthermore, the new infrastructure will help alleviate the restrictions affecting the British electricity grid, when transmission lines lack sufficient capacity, some generators are forced to reduce or temporarily halt their production. This connection will allow for better utilization of available electricity and reduce congestion problems.
National Grid seeks to strengthen Britain electricity grid
Sea Link is one of the projects included in Great Grid Upgrade, the program of National Grid Electricity Transmission intended to modernize the electrical infrastructure and expand its transport capacity.
The initiative addresses the need to adapt the grid to growing demand and the addition of new renewable energy generation facilities. To achieve this, improving connections between electricity-producing regions and those with the highest consumption is essential.
The British government also considers these investments part of its energy security strategy, a grid with greater transmission capacity facilitates the use of domestic generation and reduces limitations on electricity distribution.
Energy Minister Michael Shanks emphasized that modernizing this infrastructure will enable the connection of new renewable energy projects and support the development of business activities. He also noted its importance in reducing the country’s dependence on the volatility of international fossil fuel markets.
Sumitomo Electric will supply the HVDC cable
The Japanese company Sumitomo Electric Industries was selected in late 2025 to manufacture and install the 140 kilometers of submarine cable that the project requires.
The 525 kV cable will be produced at the company’s facilities located in the port of Nigg, Scotland, its participation represents an important component for the development of this connection, which requires specialized technology to transport large amounts of electricity under the sea.
HVDC technology allows for the transmission of energy using direct current and is particularly well-suited for long-distance submarine connections. Its use in Sea Link will enable the connection of the converter stations in Kent and Suffolk, facilitating the transport of electricity between the two regions.
Sea Link includes funding for local communities
Along with the project approval, National Grid has planned a benefits program for communities near the infrastructure. The initiative includes allocating over one million pounds to community funds in Kent and Suffolk.
These resources will be available to support local projects and contribute to the development of communities located in areas linked to the electrical connection.
With construction planned for early 2027, Sea Link is preparing to enter its construction phase as part of the UK’s broader effort to modernize its electricity transmission network.
Its 2 GW capacity, supported by a 525 kV high-voltage direct current (HVDC) submarine cable stretching 140 kilometers between Kent and Suffolk, will strengthen electricity transport across the country. The infrastructure is also expected to improve the movement of power from generation sites to areas with higher demand, helping accommodate additional renewable energy sources and support the long-term resilience of the British electricity grid.
Source: Offshore Energy
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