Interim report on power outage to be published

An interim report into the power outage that shut Heathrow Airport will be published on Thursday.

The airport was closed to all flights until about 18:00 GMT on 21 March due to an “unprecedented” loss of power caused by a fire at a nearby electricity substation, which started the previous night.

More than 270,000 air passenger journeys were disrupted.

In the immediate aftermath of the fire, the National Energy System Operator (NESO) was ordered by Energy Secretary Ed Miliband to investigate what happened and provide its initial findings within six weeks.

The NESO North Hyde Review Interim Report will focus on “establishing the timeline and sequence of events of the outage”.

It aims to “explain the roles and responsibilities of the key stakeholders involved, and outline areas of further investigation required to deliver the final report by the end of June 2025”, NESO has said.

Last month, MPs were told Heathrow Airport had been warned about its power supply in the days before the incident.

Nigel Wicking, chief executive of the Heathrow Airline Operators Committee, which represents airlines that use the west London airport, said a “couple of incidents” had made him concerned.

He told the Transport Select Committee that he spoke to the Team Heathrow director on 15 March about his concerns, then to the chief operating officer and chief customer officer on 19 March.

He said: “It was following a couple of incidents of, unfortunately, theft of wire and cable around some of the power supply that, on one of those occasions, took out the lights on the runway for a period of time.

“That obviously made me concerned and, as such, I raised the point I wanted to understand better the overall resilience of the airport.”

Heathrow insisted after the hearing that Mr Wicking was referring to matters which had “no relation” to the North Hyde substation that caught fire.

An airport source said: “To draw a comparison between these incidents is irresponsible.”

Mr Wicking said the shutdown cost airlines £60m to £100m.

Heathrow is Europe’s largest airport, with more than 83.9 million passengers travelling through its terminals in 2024.