Dismore questions Mayor over Summer power cuts

At today’s Mayor’s Question Time, Andrew Dismore AM, Labour London Assembly Member for Barnet and Camden questioned the Mayor Sadiq Khan over the resilience of the electrical supply in London, in light of the serious power cuts on 10th August 2019.

 Mr Dismore asked:

 ‘What are you doing to investigate the resilience of electrical supply to the capital, in light of the major power outages in August, which also brought chaos to main rail lines?

‘Would you agree that the impact in London was serious?  Hundreds of people were stranded at King’s Cross. At some tube stations, lights went out and staff had to guide passengers with torches. At Kentish Town in my constituency, passengers left the train and had to walk along the track. London Resilience Partnership’s Risk Register rates the risk of failure of the National Electricity Transmission as very high?

‘Do you believe increasing numbers of severe weather events due to climate change make future power cuts more likely; how could Brexit impact on electricity supply; and if so what plans have been made to respond to these risks, with ever growing demand for electricity from homes, businesses and transport?

‘On the Brexit issue, it is referred to in the Operation Yellowhammer document that was published yesterday. It says that there won’t be immediate disruption to electricity supply or gas interconnectors, but it could rapidly, within months or years after EU exit. There would not be security of supply issues, but in any event, there would be electricity price increases for consumers, business and domestic, with wider political and economic impacts. So it is likely that Brexit will have an impact on those who are less well off.’

The Mayor said that the power outages caused serious problems, and that his officers were working with energy suppliers to improve resilience across the network. Power supply is the responsibility of the National Grid and the Government, who can apply fines if the job isn’t being carried out effectively. Within City Hall, the Infrastructure High Level Group is chaired by the Deputy Mayor for Regeneration, Jules Pipe, and met with representatives from energy suppliers to make sure resilience is being imbedded. The Deputy Mayor for Fire also chairs regular meetings on resilience.

He had received reassurance from the Government on the impact of Brexit on energy supply, but they hadn’t supplied all the information and analysis that he had requested. As for the Yellowhammer document, this is the Government’s own assessment and gives reasons to be concerned. That is why the Government should be straight with us about the impact of a catastrophic no-deal Brexit.

On climate change, the Mayor said the impact of this on energy supply was a mid to long term issue, and that he was piloting different schemes to take pressure off the national grid.

 After MQT Mr Dismore added:

 ‘The Summer power cut was a real wake up call for the capital’s resilience. The challenges posed by growing demand on the grid combined with the impact of climate change and the risks of Brexit cannot be overestimated. It is good to know that the Mayor is awake to the consequences and that provision is in place to mitigate the risk of disruption from major power outages in the future.’


Notes for editors

London Resilience Partnership’s Risk Register rates the risk of failure of the National Electricity Transmission as very high. The worst-case scenario is for a total national power failure, referred to as ‘Black Start’. The Risk Register identifies a number of controls in place to prevent and handle such an incident, including:

  • A testing and maintenance regime.
  • The London Power Supply Disruption Plan
  • The EDF Energy System Emergency Plan.
  • EDF Energy Emergency Communication Plan.
  • EDF Energy Black Start Plan.
  • Business Continuity Plans for Category 1 and 2 Responders, businesses and other key organisations – Major Incident/Emergency Plans for Category 1 and 2 Responders

The impacts of a Black Start power failure are significant and wide ranging. The technical recovery process could take up to 5 days; however, there is the potential for wide area power disruptions for up to 14 days, potentially affecting millions of consumers.

The London Power Supply Disruption Framework provides an outline for the London Resilience Partnership and its strategic decision makers to support and augment the electricity companies’ response to a significant and sustained wide area power failure. This includes:

  • Providing the London Resilience Partnership with a framework for responding to a widespread power cut within London.
  • Setting out the circumstances under which a Partnership response to a wide area power failure may be triggered.
  • Setting out the process for activating a multi-agency response to a power failure.
  • Outlining the roles and responsibilities involved in providing a multi-agency response.
  • Providing information to support the timely activation and delivery of a multi-agency response.
  • Providing the London Strategic Coordinating Group (SCG) with guidance on risks and issues to enable them to make informed decisions during the response and recovery phases.
  • Identifying methods and messages to communicate with the public

The Framework can be triggered by a number of factors:

  • By the Distribution Network Operator or Transmission System Operator for a power failure affecting 10,000 or more customers or another incident that they believe requires activation of the framework
  • By a partner or a number of partners where they believe that a power failure meets the requirements for the declaration of an emergency as defined in the Civil Contingencies Act. For example, where a London wide Resilience Partnership organisation is facing significant issues as a result of a power failure that requires multi-agency strategic coordination
  • Where the significant loss of power is one of the consequences of another major incident or emergency
  • Where the power failure is a result of a significant deliberate incident This above list is not exhaustive and is not intended to preclude the framework being triggered for reasons not listed above.

The Framework identifies the following risks that may cause power supply disruptions:

  • Flooding (and other flooding risks). Severe flooding could damage electricity company assets and cause electricity cuts to both properties within and outside the flooded areas depending on the areas the assets supply.
  • Storms and Gales. Storm force winds affecting most of the South East England region for at least 6 hours. Potential for fatalities and casualties with short term disruption to infrastructure including power, transport networks, homes and businesses.
  • Low Temperatures and Snow. Snow falling and lying over most of the area for at least one week. Significant excess deaths and casualties, mainly amongst the elderly. There is likely to be some disruption to transport networks, businesses, power supply and water supply, and also school closures.

Operation Yellowhammer document: