The National Energy System Operator (NESO) has released its interim findings into the North Hyde Substation fire that caused the closure of Heathrow Airport on 20 March.
While the root cause remains unknown, the early report highlights serious questions around how the UK’s critical infrastructure handles disruption.
Commissioned by the Department for Energy Security and Net Zero and Ofgem, the review sets out a timeline of events and identifies key areas for further investigation. NESO’s final report is due by the end of June.
After six weeks of work and over 600 pieces of evidence reviewed, NESO says the incident…
exposed vulnerabilities in both infrastructure resilience and crisis coordination
NESO
A forensic fire investigation by National Grid Electricity Transmission and the London Fire Brigade is ongoing.
The Metropolitan Police has confirmed there is “no evidence to suggest that the incident was suspicious in nature”.
Key lines of enquiry include whether substation design standards were followed, how maintenance history at the North Hyde site may have played a role – and whether Heathrow’s private network was robust enough.
The report also points to a need for better coordination and communication between organisations like Network Rail, Transport for London and SSEN Distribution, all of which were affected.
NESO says the final report will offer recommendations on improving resilience across the energy system, strengthening response and restoration protocols, while agreeing a common understanding of what resilience means between sectors.
Although evidence is still being gathered, the interim findings make clear that a single substation fire exposed weaknesses across the board.
NESO will now dig deeper into technical, operational and organisational factors ahead of the final report to be published next month, which could shape future infrastructure planning and emergency response nationwide.
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