Former shadow chancellor John McDonnell has said he is “worried” that terrorists could “easily” target sites like the substation where a fire led to the shutdown of Heathrow Airport.
The Labour MP highlighted a review from the National Energy System Operator (Neso), which found that the fire at North Hyde substation in March was likely caused by a preventable technical fault.
The report found that the National Grid Electricity Transmission (NGET) failed to address an issue identified in 2018 of moisture in a transformer, and energy watchdog Ofgem has launched an investigation.
Mr McDonnell argued this report showed a "catalogue of failure" and that his constituents need reassurance.
The Hayes and Harlington MP told the House of Commons: "This is located in my constituency. I was there on the day. This was a huge fire. It was a massive fire.
"Two hundred of my constituents were evacuated from their homes during the night and smoke flowed down the street.
"This could have been so much more of a bigger disaster if it hadn't been for the firefighters who courageously went on site, the help they get from the council, but also the back-up services and the NHS."
He added: "My constituents want to be reassured and this report demonstrates the catalogue of failure. The identification of a problem in 2018, this is seven years on…
"I'm worried now that, again, sites like this could be very easily targeted by terrorist activity.
"So we need a process of reassurance and the recommendations set out in terms of what we do from here to ensure the resilience is there, I think, has to take into account that the Government has a role now in driving through this programme and recognising that we can't rely on some of these other agencies without a real government thrust of leadership, but also securing accountability, because I do not want other areas to experience what we did that night."
Responding, energy minister Michael Shanks said: "I think there are very, very serious questions to answer here, and I hope that came through in my statement, and it certainly came through in the conversation that I had with National Grid earlier.
"We are clearly seeking urgent assurances that the work that should have been done is being done, but also that there's no other situations similar to this.
"Ofgem has taken forward this and, I think, in a really serious way as well, with two reviews, one into National Grid itself, but the other into the wider energy system to see if there are any further lessons to learn.
"But he is right, and I want to just say I completely agree with the point that government does need to be front-footed on this and take a real leadership role in driving us forward, we can't leave it to individual companies to mark their own homework.
"We are doing that, and a part of that work is bringing together resilience work across government.
"But I will also soon be chairing a new group that brings together everyone who has responsibility for critical national infrastructure in our energy system to make sure that the energy security, cyber security and other threats to our infrastructure are taken seriously, but that actions are taken forward at the highest levels of government to make sure we don't have a repeat of this incident in the future."
The fire on March 20 this year was caused by a "catastrophic failure" in one of the transformers, "most likely caused by moisture entering the bushing causing a short circuit", which ignited the oil, the Neso report said.
A review by the National Grid in 2022 found the fire suppression system at the North Hyde site was "inoperable", while another assessment in July 2024 indicated the system was still "out of service", the report said.
No flights operated at Heathrow Airport until about 6pm on March 21 because of the blaze, which started late the previous night.
More than 270,000 air passenger journeys were disrupted by the closure.
The electricity outage led to 71,655 domestic and commercial customers losing power and the "complete loss of supplies" to part of Heathrow Airport's internal electrical distribution network, the report said.
