Heathrow Fire Caused by National Grid Maintenance Failure, Report Finds

A fire at Heathrow Airport in March, which caused significant disruption and stranded numerous passengers, was attributed to a failure by National Grid to properly maintain an electricity substation. This finding was revealed in an official report released on Wednesday, prompting an investigation by the energy watchdog.

The closure of Heathrow, Europe's busiest airport, resulted in substantial financial losses for airlines and raised concerns about the robustness of Britain's infrastructure. Energy Minister Ed Miliband expressed serious concern regarding the report's findings.

The report, stemming from a review of the March 21st incident conducted by the National Energy System Operator, highlighted that known risks were not adequately addressed by National Grid Electricity Transmission. Consequently, the energy regulator, Ofgem, initiated an enforcement investigation to examine potential breaches of license.

The review revealed that a "catastrophic failure" within a transformer at National Grid Electricity Transmission's substation caused the fire. This failure was likely triggered by moisture entering a bushing, leading to a short circuit and subsequent ignition of oil.

The report also noted that elevated moisture levels were detected in oil samples taken in 2018, indicating a potential fault and the need for bushing replacement. However, the existing controls failed to ensure that necessary action was taken. Furthermore, a decision to postpone basic maintenance in 2022 contributed to the issue remaining unresolved.