The initial 2.5-kilometre circuit of the £1 billion London Power Tunnels project has been switched on, connecting the Hurst substation to Crayford.
Energy Minister Michael Shanks attended the event to mark the occasion.
This project is part of a larger scheme to upgrade London’s electricity network, which includes constructing an additional 30 kilometres of tunnels and a new substation using SF6-free technology.
The previous cables in this area, operational since 1967, were nearing the end of their lifespan.
The work aims to improve the reliability and capacity of the power supply across the capital.
The first phase of this project was completed in 2018, focusing on North London.
Alice Delahunty, president of National Grid Electricity Transmission, said: “There’s still a way to go on the project, but the Hurst-Crayford circuit seeing volts for the first time is a tremendous achievement for our National Grid teams and supply chain partners.
“It’s hard to overstate what an engineering challenge it has been to build over 30 kilometres of tunnels under London to upgrade and futureproof the capital’s electricity supplies, so the project’s progress to date is a real testament to all those involved.”
Energy minister Michael Shanks said: “The London Power Tunnels show British infrastructure at its best and I congratulate the efforts of everyone involved, as this new circuit switches on to power up homes and businesses across the capital.
“It is feats of incredible engineering, such as this, that will be the driving force behind our race to become a clean energy superpower and help to revive communities across the UK with new skilled jobs.”
