According to a report, Heathrow Airport is contemplating taking legal action against National Grid after it was discovered that a known fault at an electrical substation owned by the company caused a fire that resulted in the airport’s shutdown.
The investigation revealed that National Grid was aware of the problem since 2018 but failed to address it, despite numerous opportunities to fix it. The report also stated that the maintenance of the North Hyde substation, which supplies Heathrow, was repeatedly postponed, leading to moisture affecting electrical components.
Heathrow has expressed disappointment in National Grid’s failure to prevent the fire and expects the company to take responsibility for the damages and losses incurred by the airport and airlines. National Grid, on the other hand, claims to have taken action since the incident and asserts that such events are rare in the UK, which has a highly reliable network. However, the company has not yet responded to Heathrow’s potential legal case.
In response to the report, energy regulator Ofgem has launched its own investigation into National Grid.
The power cut caused by the fire resulted in the closure of Heathrow, the UK’s largest airport, causing thousands of cancelled flights and stranded passengers. The National Energy System Operator (Neso) stated that the fire was caused by moisture entering electrical components at the substation.
Neso also revealed that elevated moisture levels were detected in July 2018 and, according to National Grid’s guidance, this indicated an imminent fault and required the replacement of the bushing, an insulating material used around electrical parts. However, this issue was left unaddressed, and basic maintenance to fix it was deferred until 2022.
The shutdown of Heathrow affected over 270,000 journeys and had a ripple effect on essential services such as road, rail, and Hillingdon Hospital, according to Neso. Airlines based at Heathrow estimated that the closure cost them between £80m to £100m.
This incident has raised concerns about the resilience of the UK’s major infrastructure. Fintan Slye, Neso’s chief executive, stated that while the report did not intend to assign blame, National Grid is responsible for maintaining its equipment and ensuring its fitness for operation.
The report also revealed that National Grid was not aware of the crucial role the North Hyde substation played in powering Heathrow, despite the airport being aware of it. Mr. Slye stated that the transformer should have been taken out of service and the fault repaired when elevated moisture levels were first detected in 2018. However, this was not done, and the situation worsened over time, resulting in the fire. He described the report as a story of missed opportunities.
After announcing its investigation, Ofgem’s director general for infrastructure, Akshay Kaul, stated that energy companies should properly maintain their equipment and networks to prevent such incidents from happening. He added that they would take action and hold companies accountable if there is evidence that they have failed to do so.
National Grid claims to have a comprehensive asset inspection and maintenance program in place, which includes re-testing the resilience of substations that serve critical infrastructure. The company has also promised to cooperate with Ofgem’s investigation. Mr. Slye believes that there was a missed opportunity at Heathrow to enhance its energy resilience and that the energy industry needs to improve its understanding of critical infrastructure resilience.
The report also highlighted that energy network operators are not generally aware of whether their customers are considered Critical National Infrastructure.