Fire that closed Heathrow traced to unrepaired transformer

The occurrence broke retired astatine the North Hyde substation successful West London connected March 20. Photo: STR / AFP
Source: AFP

A occurrence astatine an electrical substation that forced a shutdown astatine London's Heathrow Airport successful March was apt caused by moisture entering electrical components, a occupation archetypal flagged successful 2018, a study said Wednesday.

Water entering a transformer and causing a abbreviated circuit "most likely" started the fire, according to the National Energy System Operator (NESO) report, adding that elevated moisture readings were detected successful July 2018 but "mitigating actions due to its severity were not implemented".

The occurrence broke retired astatine the North Hyde substation successful West London, astir 2 miles (3.2 km) northbound of Heathrow, astatine 11:21 p.m. connected March 20, resulting successful a implicit nonaccomplishment of powerfulness proviso to portion of the airport's backstage interior electrical organisation network.

The airdrome was closed for astir of March 21, affecting astir 270,000 journeys and raising superior questions astir the reliability of 1 of the UK's astir captious pieces of infrastructure.

Using forensic investigation from the National Grid Electricity Transmission and London Fire Brigade, the government-commissioned study concluded that "a catastrophic failure" connected precocious voltage "bushing" components caused a occurrence to ignite connected the transformer.

"This was astir apt caused by moisture entering the bushing causing a abbreviated circuit. The energy apt past 'arced' (causing sparks) which combined with aerial and vigor to ignite the oil, resulting successful a fire," it added.

An elevated moisture speechmaking successful 1 of the bushings had been detected successful lipid samples taken successful July 2018, indicating "an imminent responsibility and that the bushing should beryllium replaced".

Flights were grounded and the airdrome unopen aft the substation fire. Photo: STR / AFP
Source: AFP

However, "controls successful spot were not effectual and failed to place subsequently that enactment had not been taken successful narration to the elevated moisture reading," it said.

"This includes an accidental successful 2022 erstwhile a determination was taken to defer basal maintenance. The contented truthful went unaddressed," added the report.

'Risks were not addressed'

Energy Minister Ed Miliband called the study "deeply concerning".

"Known risks were not addressed by the National Grid Electricity Transmission, and (energy regulator) Ofgem has present opened an authoritative enforcement probe to see immoderate imaginable licence breaches," helium said successful a statement.

The National Grid responded successful a connection that "we afloat enactment the recommendations successful the report" and that "we volition besides cooperate intimately with Ofgem's investigation".

Around 230,000 passengers usage Heathrow each time -- 83 cardinal a twelvemonth -- making it 1 of the world's busiest airports. Planes from Heathrow service astir 80 countries.

The airdrome welcomed the report, which it said "sheds further airy connected the outer powerfulness proviso failure".

"A operation of outdated regulation, inadequate information mechanisms, and National Grid's nonaccomplishment to support its infrastructure led to this catastrophic powerfulness outage," a spokesperson said.

"We expect National Grid to beryllium cautiously considering what steps they can instrumentality to guarantee this isn't repeated."

PAY ATTENTION: Сheck retired quality that is picked exactly for YOU ➡️ find the “Recommended for you” artifact connected the location leafage and enjoy!

Source: AFP