A massive fire at the North Hyde electrical substation in Hayes is still smouldering nearly 36 hours after it first erupted, leaving a trail of destruction that plunged West London into darkness, disrupted Heathrow Airport operations, and impacted tens of thousands of residents.

The blaze, described by officials as a "raging inferno", broke out at around 11:25pm on Thursday night (March 20) after a transformer containing 25,000 litres of cooling oil exploded. Despite round-the-clock efforts by emergency crews, 5% of the substation remains alight, according to the London Fire Brigade (LFB).

Severe Impact on Power Supply and Heathrow Operations

The explosion caused a massive power outage, initially cutting electricity to more than 67,000 homes, and forced the cancellation of 1,300 flights from Heathrow Airport, where Terminals 2 and 4 were particularly affected. Travel chaos ensued, with an estimated 200,000 journeys disrupted, and airlines incurring millions in losses.

While power has since been partially restored, thousands of homes remain without electricity as of Saturday morning. The incident also prompted the closure of several local schools, while emergency arrangements—including extra bin collections—were enacted by Hillingdon Council to support affected residents.

Firefighting Efforts Continue

At the peak of the response, 70 firefighters and 10 fire engines battled the blaze, which took over seven hours to bring under control. However, lingering hotspots continue to burn, with firefighters maintaining a visible presence on site to fully extinguish the fire.

LFB said in a statement:

The fire involved a transformer comprising 25,000 litres of its cooling oil fully alight. This created a major hazard owing to the still live high-voltage equipment and the nature of an oil-fuelled fire. As of the most recent update, approximately 5% remains alight in isolated hotspots, and we will maintain a presence at the site until the incident is resolved.”

Locals continue to report a strong smell of smoke in the area, with one witness noting: "It’s not going away."

Counter-Terror Police Assess Incident

Due to the scale and impact of the explosion, counter-terror police were called in as a precaution to assess any potential links to sabotage. However, the Metropolitan Police has since confirmed the incident is not being treated as suspicious.

Commander Simon Messinger, who is overseeing the police response, said:

"The investigation into the cause of the fire remains in its early stages. After initial assessment, we are not treating this incident as suspicious, although enquiries do remain ongoing."

Wider Concerns Raised

The event has raised serious concerns about infrastructure resilience, with some commentators warning that the disruption exposes vulnerabilities in the UK’s energy and transport systems.

Prime Minister Sir Keir Starmer issued a statement:

"I know the situation in Heathrow is causing distress and disruption, especially for those travelling or without power in their homes. I’m receiving regular updates and I’m in close contact with partners on the ground. Thanks to our emergency workers for keeping people safe."

What Happens Next

Power provider Scottish and Southern Electricity Networks (SSEN) is continuing efforts to restore full power, though officials caution that some outages may persist into the coming days. A full investigation into the incident is being carried out by fire and electrical safety specialists, alongside continued support for residents and businesses affected.

Residents are advised to check local council updates and SSEN communications for restoration timelines and public safety information.

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