Major Milestone In Construction Of New National Grid Substation In Kent
Construction of National Grid’s new substation at Wallend on the Isle of Grain, Kent, which will play a key role in strengthening the UK’s electricity transmission network, has achieved a key milestone with completion of the building hall that will house the gas-insulated switchgear (GIS).
The Wallend Substation is a vital new piece of infrastructure that will play a key role in supporting the transition to cleaner, more secure energy. The next phase of this major infrastructure project will now focus on the installation and testing of the GIS And associated electrical equipment before the substation connects to the electricity network.
Once operational, the substation will facilitate the connection of NeuConnect, a new 1.4 gigawatt (GW) HVDC interconnector that will link the UK and Germany energy markets for the first time. Located alongside key strategic assets including Grain LNG and the BritNed Interconnector, Wallend Substation further reinforces the Isle of Grain’s position as one of the UK’s most important energy hubs. The new infrastructure will improve grid stability, enhance system flexibility and support the UK Government’s Clean Power 2030 ambitions.
Construction programme sees strong progress
Main construction works began in 2025, with National Grid working alongside Principal Contractor Balfour Beatty who are leading the design and build of the new substation. The project has now reached a significant milestone, with the completion of the main building structure, including foundations, steelwork and external cladding.
The next phase will see the installation of EconiQ GIS technology from Hitachi Energy, which is free from sulphur hexafluoride (SF₆), a potent greenhouse gas. This represents another step in National Grid’s commitment to reduce SF₆ emissions by 50% by 2030. Factory acceptance testing for the GIS has already been successfully completed, enabling installation to commence.
The completed cladding provides effective weather protection and insulation in readiness for the installation of the substation’s electrical systems, while also helping to reduce operational noise once the site is energised.
Supporting the local community
Local community organisations can apply to National Grid’s Community Grant Programme (CGP), which is designed to support projects in areas directly affected by the construction of Wallend Substation. Grants of up to £20,000 are available for initiatives delivering clear social, economic or environmental benefits.
The programme supports projects focused on inclusion, education, health and wellbeing, employability, conservation and energy efficiency, helping to ensure a positive and lasting legacy alongside the delivery of nationally significant infrastructure.
Hannah Ward, EPC Project Manager at National Grid Electricity Transmission, said:
“The Wallend Substation represents a key investment in strengthening the UK’s electricity network and enabling cleaner, more secure power for the future. Completion of the main building structure is an important milestone in the construction programme and a clear sign of the progress being made on site.
“We are proud to be delivering this critical infrastructure while working closely with our partners and the local community to ensure it brings lasting benefits to the Isle of Grain.”