An electrical substation fire that shut down Heathrow Airport, canceling greater than 1,300 flights, was brought on by a preventable technical fault identified almost seven years earlier, a report found Wednesday.
Europe’s busiest air hub shut for about 18 hours in March after a fireplace knocked out considered one of the three electrical substations that offer Heathrow with power. Greater than 270,000 passengers had journeys disrupted.
Counterterrorism police initially led the investigation into the fireplace, which got here as authorities across Europe girded against sabotage backed by Russia.
Though authorities quickly ruled out vandalism or sabotage, the fireplace’s huge impact raised concern concerning the resilience of Britain’s energy system to accidents, natural disasters or attacks.
The federal government ordered an investigation into “any wider lessons to be learned on energy resilience for critical national infrastructure.”
The report by the National Energy System Operator said that an “elevated moisture reading” had been present in oil samples on the substation in west London in July 2018, but motion wasn’t taken to interchange electrical insulators often known as bushings.
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It said that the March 20 blaze was brought on by a “catastrophic failure” in considered one of the transformers, “more than likely brought on by moisture entering the bushing causing a brief circuit” that ignited the oil.
The report also said Heathrow underestimated the likelihood of losing considered one of its three power sources, and because of this, “its internal electrical distribution network was not designed or configured to benefit from having multiple supply points to supply quick recovery following such a loss.”
Energy Secretary Ed Miliband said that the findings were “deeply concerning.” He said that energy industry regulator Ofgem had opened an investigation into whether the substation’s operator, National Grid Electricity Transmission, had breached its license conditions.
National Grid said that Britain has “one of the reliable networks on the earth, and events of this nature are rare. National Grid has a comprehensive asset inspection and maintenance program in place, and now we have taken further motion because the fire.”
© 2025 The Canadian Press