LONDON: A fireplace that shut Heathrow airport in March, stranding thousands of passengers, was brought on by Nationwide Grid’s failure to keep up an electrical energy substation, an official report mentioned on Wednesday, prompting the vitality watchdog to open a probe.
The closure of Heathrow, the busiest airport in Europe, price airways tens of hundreds of thousands of kilos. It additionally raised questions in regards to the resilience of Britain’s infrastructure.
Vitality minister Ed Miliband mentioned the report was “deeply regarding”.
The report follows a evaluate of the incident on Mar 21 by the Nationwide Vitality System Operator, which manages the electrical energy community and was separated from Nationwide Grid final yr.
Because of the report, Britain’s vitality regulator Ofgem launched an enforcement investigation into Nationwide Grid Electrical energy Transmission, which owns and maintains the high-voltage electrical energy transmission community in England and Wales.
The report mentioned its evaluate had seen proof {that a} “catastrophic failure” on one of many transformer’s excessive voltage bushings at Nationwide Grid Electrical energy Transmission’s 275kV substation triggered the transformer to catch fireplace.
“This was most probably brought on by moisture getting into the bushing, inflicting {an electrical} fault,” it mentioned.
It mentioned Nationwide Grid controls in place weren’t efficient and did not determine that motion had not been taken in relation to an elevated moisture studying in 2018.
A Nationwide Grid spokesperson mentioned that the corporate had a complete asset inspection and upkeep programme in place and that it had taken additional motion for the reason that fireplace.
“There are essential classes to be learnt about cross-sector resilience and the necessity for elevated coordination,” the spokesperson mentioned.
Ofgem mentioned the evaluate had “established that the basis reason behind the fireplace was a preventable, technical fault”.
It plans to evaluate whether or not Nationwide Grid complied with the related laws and licence circumstances referring to the event and upkeep of its electrical energy system near Heathrow.
The regulator will even fee an unbiased audit into Nationwide Grid property to evaluate whether or not the failings have been a one-off or systemic, it mentioned.
