London Activates Train-Sized Underground Power Tunnel

South London has officially activated a massive 18-kilometer underground power tunnel, the size of a train, to begin transmitting electricity. This 50-meter-deep tunnel is part of the London Power Tunnels phase 2 (LPT2) project, a £1 billion investment spanning 32.5 kilometers across seven South London boroughs. The new tunnel system replaces aging underground cables used since the 1960s, moving power transmission from shallow street-level conduits to deep underground tunnels, significantly improving power supply reliability. The project, which began in 2019, was constructed in three phases and connects multiple National Grid substations. Following the completion of the North London Power Tunnels project in 2018, this represents a major upgrade to the UK capital’s power infrastructure, providing more reliable energy security for future urban development.