Britain’s next subsea electrical highway has confirmed £3bn of major supply chain contracts, marking a significant step forward in delivering critical energy infrastructure while supporting economic growth, UK energy security and reducing grid constraint costs.

A contract has been awarded to Siemens Energy to provide the high voltage direct current (HVDC) converter stations for Eastern Green Link 4 (EGL4), following the earlier confirmation of a £2bn contract with Prysmian to supply the subsea and underground electricity cables.

The link, a joint venture between SP Energy Networks and National Grid Electricity Transmission, is one of five subsea links being developed along the east coast of Britain. Together, these projects will strengthen the resilience of the electricity network, reduce grid constraints and enable greater volumes of renewable energy to flow efficiently between Scotland and England to millions of homes, strengthening UK energy security.

As part of a new era of investment in electricity network infrastructure, projects like EGL4, are supporting a multi-billion-pound supply chain, which is creating skilled jobs and industrial opportunities in emerging energy sectors, contributing to economic growth and building long-term skills capability in the UK, critical to the energy transition.

The Siemens Energy contract includes two converter stations, one in Fife in Scotland and one in Norfolk in England. The converter stations change alternating current into direct current, the most efficient way for high voltage electricity to travel across large distances. Once converted, the electricity will travel around 640km, primarily undersea, before being converted back again to join the onshore transmission network.

By increasing capacity and reducing congestion on the grid, the 2GW EGL4 subsea link, will help minimise constraint costs by accelerating the integration of cleaner sources of energy into the system, supporting the UK’s ever-increasing demand for energy.

James Goode, project director of Eastern Green Link 4, said: “Confirming £3bn of contract awards demonstrates the scale and momentum behind Eastern Green Link 4 as we move into delivery. By bringing together the proven expertise of Siemens Energy and Prysmian, we’re building a highly capable UK supply chain to deliver this complex electricity infrastructure project.

“These agreements not only give us the confidence to progress at pace but also highlight how investment in network infrastructure can and will support UK economic growth, strengthen domestic capability and unlock the capacity needed to transport renewable energy efficiently, supporting both UK energy security and a cleaner energy system.”

Darren Davidson, UK vice president for Siemens Energy, added: “Eastern Green Link 4 is a critical project for strengthening the UK’s electricity network and enabling more renewable power to flow between Scotland and England. Working with our partners, at SP Energy Networks, National Grid Electricity Transmission and Prysmian, we’re investing in the supply chain to deliver this nationally significant HVDC infrastructure.

“With more than 7,000 people employed by Siemens Energy across the UK, including at our centre of excellence in Manchester, this project highlights how investment in grid infrastructure supports skilled jobs, energy security and the UK’s long-term transition to a more resilient energy system.”

Subject to planning consent, Eastern Green Link 4 is expected to enter main construction in 2028 and is scheduled to be complete in 2033.

Together, SP Energy Networks and National Grid Electricity Transmission are also building the Eastern Green Link 1 project, expected to be complete in 2029.