Construction of National Grid's new Wallend Substation, a key addition to the UK’s electricity transmission network, has reached a major milestone with the completion of the building hall that will house its gas-insulated switchgear (GIS).

The substation will support the UK's transition to cleaner and more secure energy, and will facilitate the connection of NeuConnect HVDC interconnector, linking the UK and German energy markets for the first time. Positioned near strategic assets including Grain LNG and the BritNed Interconnector, the new substation will enhance grid stability, system flexibility, and support the UK Government's Clean Power 2030 ambitions.

Main construction began in 2025, with Balfour Beatty serving as Principal Contractor. The project has now completed the main building structure, including foundations, steelwork, and external cladding.

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.

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"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."

The next phase will focus on installing and testing Hitachi Energy’s EconiQ GIS technology, which is free from sulphur hexafluoride (SF₆), helping National Grid reduce SF₆ emissions by 50% by 2030. Factory acceptance testing for the GIS has already been completed, and the cladding will provide weather protection, insulation, and noise reduction for the operational substation.

Tony Wilson, Managing Director of Balfour Beatty's Power Transmission & Distribution business, added: "Completion of the main building structure at the new 400kV Wallend Substation marks an important milestone in this nationally significant project.

"Working in close partnership with National Grid, we are proud to be strengthening the electricity network and enabling the delivery of cleaner, more secure energy. We now turn our focus to the next phase of the programme, installing the critical equipment that will connect the substation to the wider network and support the UK's long‑term energy needs."

Local community organisations are invited to apply for grants of up to £20,000 through National Grid’s Community Grant Programme, supporting initiatives in inclusion, education, health, employability, conservation, and energy efficiency to deliver lasting benefits alongside the infrastructure project.