A fire at a power substation caused London’s Heathrow Airport to shut down in March, leaving thousands of travelers stranded. An official report released Wednesday revealed that the blaze was triggered by a failure in the UK power grid to properly maintain the electricity equipment. This sparked an investigation by the energy regulator, Ofgem.
Heathrow is Europe’s busiest airport, so the closure had a big impact. Airlines lost tens of millions of pounds, and the incident raised serious questions about how well Britain’s infrastructure can handle emergencies.
The fire happened on March 21 at a 275-kilovolt substation run by National Grid Electricity Transmission (NGET). The report found that a key part of the transformer, called a high-voltage bushing, failed and caught fire. The most likely cause was moisture getting inside the bushing, which created an electrical fault.
This wasn’t a sudden problem. Back in 2018, NGET detected high moisture levels in the bushing, which should have triggered a replacement. But the company didn’t fix the issue. Even in 2022, when they had a chance to do basic maintenance, they postponed it, leaving the fault to grow.
Ed Miliband, the energy minister, called the findings “deeply concerning.” Ofgem described the fire as “preventable” and said it was caused by a technical fault that should have been dealt with years ago.
Following the report, Ofgem has launched a formal investigation into National Grid’s role. They want to see if the company broke any rules about keeping the electricity system safe near Heathrow. An independent audit will also check if this failure was a one-time mistake or part of a bigger problem.
Heathrow Airport reacted by saying it expects National Grid to take full responsibility. The airport is also thinking about whether to take legal action. Both the airport and airlines could face costly payouts for the disruption caused to passengers.
National Grid defended itself by saying it has a detailed maintenance program and has taken new steps since the fire. The company also pointed out the need for better coordination between different sectors to handle emergencies.
Heathrow’s own review found that the airport’s response to the power outage was effective, and that different actions would unlikely have changed the outcome on the day.
This incident has sparked a wider conversation about the safety and resilience of Britain’s critical infrastructure. With such a major airport suffering a shutdown due to preventable failures, officials and companies alike are under pressure to make sure it doesn’t happen again.