The Department for Energy Security and Net Zero (DESNZ) and Ofgem have asked the National Energy System Operator to produce an initial assessment within six weeks and a full report by the end of June on a substation fire at North Hyde in Hayes, Middlesex.
The fire in the late evening of Thursday 20 March resulted in over 60,000 customers and businesses losing power and had significant secondary impacts on aviation, due to the associated closure of Heathrow Airport. DESNZ noted that :”Power was quickly restored to impacted customers, and Heathrow restarted operations from late 21 March. However, there was significant disruption at Heathrow Airport over the weekend of 22 and 23 March”.
NESO will review the incident “to identify lessons and recommendations for the prevention, and management of future power disruption events, and lessons for Great Britain’s energy resilience more broadly”.
Under the terms of reference for the review, NESO will report on three topics:
1. Resilience of energy infrastructure:
The root cause, other contributing factors and sequence of events of the outage at North Hyde electricity substation and subsequent supply disruption in the surrounding area (alongside the London Fire Brigade investigation).
Direct and secondary impacts of the event across GB electricity networks, electricity customers, and critical national infrastructure, including why it resulted in the closure of Heathrow;
Areas of good practice and where improvements are required for continued energy system resilience, considering relevant aspects such as asset management (including on or off-site mitigations), networks supporting the operation of critical national infrastructure (including internal networks that connect to the transmission or distribution systems) and future development of the electricity system;
2. Response and restoration of energy infrastructure:
Consider what contingency planning had been undertaken in relation to the failure of electricity infrastructure, and assess whether the plans were enacted as planned and delivered as expected during the incident; and
Timeliness and effectiveness of the response to the incident, including communications with relevant stakeholders and the public.
3. Enhancing the resilience of critical infrastructure to energy disruption:
Make recommendations for improving the resilience of essential services, including critical national infrastructure, to power disruption.
The review will focus on the resilience of Great Britain’s energy system, given NESO’s remit to provide independent advice on the security and resilience of the whole energy system. However, key findings and lessons will be shared with Northern Ireland as appropriate to ensure UK wide resilience to energy risks.
NESO’s final report to the Secretary of State and Ofgem by end of June 2025, which will include recommendations and lessons for the future and where possible, a proposed implementation plan.