A train-sized tunnel is now carrying electricity under South London

Electricity has started flowing through a deep-level tube train sized tunnel running through South London.
New power cables map (c) National Rail
The first of two new circuits that connect National Grid’s New Cross substation in Southwark with its Hurst substation in Bexley is now live, running for 18km beneath South London through tunnels up to 50 metres deep.
This new link replaces one of two buried cables that have served the capital since the 1960s, with the other to be replaced when t