National Grid has energised a major section of its £1bn London Power Tunnels 2 (LPT2) scheme, with electricity now running through the first of two new transmission circuits between New Cross and Hurst.
The newly operational circuit connects National Grid’s New Cross substation in Southwark with its Hurst substation in Bexley, running for 18km through deep underground tunnels beneath South London, at depths of up to 50m.
The new underground link replaces one of two older buried cables that have supplied London since the 1960s.
The second legacy cable is due to be taken out of service and replaced when the remaining New Cross–Hurst circuit is brought online in the new year.
At nearly 22km in length, the original cables have been among the longest alternating current transmission links on the England and Wales system.
Joe Senior, project director at National Grid Electricity Transmission, said: “Switching on this circuit on a new part of our London Power Tunnels 2 project is a significant achievement for our engineering and delivery teams. This milestone in the project marks another step in reinforcing London’s electricity network and keeping the city connected to safe and reliable power into the future.”
According to National Grid, the newly energised connection supplies electricity to around 340,000 properties in Southeast London.
Power is transmitted into UK Power Networks’ distribution system via National Grid’s substations at New Cross and Hurst.
Earlier energisations under the LPT2 programme took place on the first two circuits between Hurst and Crayford, along a 2.5km stretch forming the most easterly part of the route.
Those sections were brought into service in August 2024 and March 2025.
Work on London Power Tunnels 2 began in 2019. The entire project extends 32.5km from Wimbledon to Hurst, running through seven South London boroughs.
National Grid is delivering the programme alongside contractors Hochtief-Murphy Joint Venture (HMJV), Taihan, Balfour Beatty and Linxon.
Mete Coban, deputy mayor of London for energy and environment, said: “It’s fantastic to see electricity flowing through a new part of the London Power Tunnels. This circuit ensures homes, schools and local communities in South London are one step closer to having the power they need for the future, as we continue building a better London for everyone.”
