In the event of major energy outages, the priority for London’s transport system is to ensure safety for all users. Transport for London (TfL) has robust plans in place to respond to outages and officers work closely with counterparts in Network Rail to ensure plans for resilience and recovery of services in the event of energy outages are aligned.
On 9 August, National Grid encountered a rare event that resulted in power outages across England and Wales, affecting nearly 1 million people. As a result of this fault, the Energy and Emergencies Executive Committee has been tasked to investigate whether procedures are fit for purpose.
During this event, no electrical supplies to London Underground were lost. However, the failure caused a brief drop of voltage and frequency which led to loss of service on the Victoria Line. TfL was able to restore the service within 35 minutes.
London Underground’s power supplies are designed and configured to be resilient to damage or failure. Had the power supply to London Underground been lost, appropriate systems and procedures would have been implemented to ensure the safety of customers. Firstly, the Local Emergency Power Supply (LEPS) provision at each station would have guaranteed power to support emergency evacuation. Should the outage have been longer, the Central Emergency Power Supply (CEPS) would have supplied power to ensure safe evacuation of the network.
TfL’s traffic lights can be affected by regional power outages, however repairs to these are prioritised by Distribution Network Operators to restore service as is practicable. For longer outages temporary lights can be deployed, and TfL’s Network Management Control Centre can deploy traffic management measures to minimise the risk of a road traffic collision at a junction where traffic signals have failed.