Balfour delivered the cabling works for phase one of the project, north of the Thames, in 2017 and will now start on the second phase of the scheme to ‘rewire London and connect with the capital’.

Works will include installing 200km of 400kV cables within a 32.5-kilometer tunnel network, deep below the ground between Wimbledon and Crayford.

Connecting several substations across the city, the cables will run through an underground tunnel network to minimise disruption to local communities and the travelling public when future maintenance and repair works are required.

Balfour Beatty will deploy the second generation of its Automated Cable Installation Equipment (ACIE) machine.

Developed in-house and utilised on the first phase of the scheme, the second-generation machine features laser sensors and cameras to improve the speed and quality of the works.

The ACIE has also revolutionised the safety of tunnel cable installation works by reducing the number of people required within the underground tunnels manually installing the cables.

Ian Currie, Managing Director of Balfour Beatty’s Power Transmission and Distribution business said: “We are delighted to be working with National Grid once again. Our world leading expertise and innovation in tunnel cable installation, combined with our deep sector knowledge, makes us ideally positioned to successfully deliver this critical piece of national infrastructure.”

Cable installation work will begin in January 2023 with the full package of works expected to be completed in 2026. At peak construction, Balfour Beatty will employ a workforce of around 150 people, as well as approximately eight apprentices.