Ofgem Approves Early Investment in Three Major UK Electricity 'Superhighways'

Ofgem Fast-Tracks Critical Electricity Infrastructure

Ofgem, the UK's energy regulator, has given its approval for early investment and updated delivery dates for three major electricity 'superhighways' across Great Britain. This decision, announced on December 9, 2025, marks a significant step towards bolstering the nation's energy security and accelerating its clean power ambitions. The projects are designed to integrate more homegrown clean energy, particularly from offshore wind, and are expected to deliver substantial savings for consumers.

The approval falls under Ofgem's Accelerated Strategic Transmission Investment (ASTI) framework, which was specifically designed to fast-track the assessment of 26 strategically important electricity transmission projects. This framework streamlines the regulatory approval process, allowing for earlier construction and pre-construction funding, thereby accelerating project build schedules.

Key Projects to Enhance Grid Capacity

The three projects receiving early investment are:

• Eastern Green Link 3 (EGL3): A proposed subsea cable with a 2GW capacity, designed to transport electricity generated from British offshore wind between Scotland and England. This is a joint venture involving National Grid Electricity Transmission (NGET), Scottish Hydro Electric Transmission (SHET), and Scottish Power Transmission (SPT). Its target delivery date is August 2034.
• Eastern Green Link 4 (EGL4): Also a proposed subsea cable with a 2GW capacity, mirroring EGL3's purpose of connecting Scottish offshore wind to England. It is also a joint venture between NGET, SHET, and SPT, with a target delivery date of August 2034.
• GWNC: An onshore 400Kv electricity link planned between Grimsby and Walpole in Lincolnshire. This link will help transport energy to consumers and has a target delivery date of December 2033.

These high-capacity transmission links are crucial for enabling consumers to access more homegrown clean power. They will also reduce the need for payments made to wind farms to switch off when there is insufficient grid capacity to transport their energy, a phenomenon known as 'constraint costs'.

Projected Savings and Consumer Impact

A Cost Benefit Analysis by grid operator NESO indicates that the redesigned projects are expected to deliver a £3-6 billion benefit to consumers compared to the original network design. This is primarily attributed to earlier achievable delivery dates and avoided network constraint costs. Ofgem's Director of Major Projects, Beatrice Filkin, stated that 'Today's decision puts these projects in a prime position to compete in the global race for sought after components such as HVDC cables and work towards seeking planning approval.'

While the wider £28 billion investment package, which includes these projects, is projected to add approximately £108 to dual fuel household bills by 2031 (£48 for gas and £60 for electricity), Ofgem emphasizes that this investment will ultimately lead to an estimated £80 saving compared to a scenario without grid expansion. This results in a net increase of around £30, or less than £3 per month, with costs expected to decrease further over time as more renewable electricity generation lowers wholesale power costs.

Towards a Resilient and Decarbonised Future

This early investment is a critical component of the UK's strategy to meet its decarbonisation goals and reduce its reliance on volatile international gas prices. By accelerating the delivery of these vital infrastructure projects, the UK aims to build a more resilient, secure, and clean energy system for the future. The projects are expected to be operational by the early 2030s, significantly sooner than previous estimates.