Contracts have been signed for the converter stations and cable system that will form the Eastern Green Link 3 (EGL3), the UK’s largest ever electricity transmission project.
The agreements appoint Hitachi Energy to deliver the high voltage direct current (HVDC) converter stations at sites in Aberdeenshire, Scotland, and West Norfolk, England, while Danish firm NKT will supply the subsea and underground cable to join the two. Together the contracts are worth almost £3bn and cover a 690km link, including roughly 580km of offshore cable, that the companies say will be capable of carrying enough electricity for about 2M homes.
EGL3 is designed to boost transmission capacity between Scotland and England and is aimed at easing so‑called “constraint” costs – payments made when wind farms are asked to turn down generation because grid capacity is limited. Project backers say the link will relieve bottlenecks affecting offshore and east‑coast renewable generation, strengthen energy security and help reduce consumer bills by allowing more home‑grown clean power to flow to demand centres.
The scheme is being developed by National Grid Electricity Transmission and SSEN Transmission, who have described Hitachi Energy and NKT as strategic delivery partners across their programme of grid upgrades. Officials underlined the emphasis on securing a resilient supply chain and capturing economic benefits within the UK as part of the rationale for large contracts.
Planning progress is at different stages on each side of the border. The converter station site in Scotland has already obtained planning in principle via the Netherton Hub process, while proposals for the English works have undergone two rounds of public consultation; a formal planning application for the English element is expected to be submitted later this year. Subject to approval by the secretary of state for energy security and net zero, construction is due to start in 2028 and the link is forecast to be energised in 2033.
EGL3 is one of several major transmission projects planned to cope with rapidly expanding offshore wind capacity. Two other Scotland-England interconnectors EGL1, between Torness and Durham, and EGL2, between Peterhead and Drax, are both under construction. Several other interconnectors – including those to other nations’ energy grids – are in development.
Increasing the number of long‑distance high‑voltage links is widely regarded as necessary to integrate intermittent renewables, reduce curtailment of generation and improve system flexibility. However, projects of this scale face complex technical, environmental and consenting challenges – particularly for extensive subsea routes – and have historically been prone to delays and cost increases.
If delivered on schedule, EGL3 would increase cross‑border transmission capacity and contribute to the UK’s targets to expand renewable generation. But the timetable still depends on securing final planning consents and executing technically demanding offshore and onshore works over the next decade.
Mark Brackley, project director for EGL3 at National Grid, said: “Signing these contracts is a major milestone for EGL3 and for the joint venture between National Grid and SSEN Transmission. By working with world‑class supply chain partners, we are investing in infrastructure that will reduce constraint costs, strengthen energy security and ensure more clean electricity can flow to homes and businesses across the country, while also supporting jobs and economic growth in the regions.”
James Johnson, EGL3 deputy project director, said: “EGL3 is a vital investment in the UK’s future energy system. By securing these major contracts, we’re taking a decisive step towards strengthening the electricity network so more clean, homegrown power can flow from where it’s generated to where it’s needed most. This project will play a key role in cutting constraint costs, supporting consumer affordability and delivering long‑term economic benefits, while building the resilient infrastructure required to meet the UK’s energy security and clean power ambitions.”
Niklas Persson, managing director of Hitachi Energy Business Unit Grid Integration said: “We’re proud that Hitachi Energy’s HVDC technology and execution capabilities will play a central role in EGL3.This link is a critical step in strengthening the UK’s transmission backbone, making sure renewable power reaches the grid when and where it’s needed – maximizing its potential and supporting a more secure and sustainable energy system. What truly sets this partnership apart is its focus on long‑term planning, that enables Hitachi Energy to scale our human capabilities, coordinate with suppliers, and align the entire value chain well in advance. This is how we ensure predictability, manage complexity, and ultimately deliver high‑performance transmission projects safely, on time, and within budget, together.”
Claes Westerlind, president and CEO of NKT, said: “Signing the contract for EGL3 is a significant milestone for NKT and for the reinforcement of Great Britain’s power system. We are proud to take this important step together with National Grid and SSEN Transmission, strengthening our long‑term collaboration and reflecting the trust our partners place in NKT as we work to advance the UK’s energy transition. With our proven expertise in HVDC technology, we look forward to delivering the cable systems that will reinforce the grid and support a cleaner, more reliable energy future.”
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