Investigators developed the burnt remains of a power sub -setting near the Heathrow airport in London on Friday, looking for the cause of a spectacular flame that closed the most crowded travel hub of Europe for most of the day and raised wider questions about British energy infrastructures.
Energy officials and experts said that a defect in a transformer with 275,000 volts that crossed it probably aroused a huge oil -powered fire that interrupted the airport and tens of thousands of nearby houses from the electricity grid. The systems designed to prevent such a apparently failed fire and the size of the fire seemed to prevent a second transformer in the vicinity of restoring electricity.
But the mystery of what caused that fault first remained far from resolved by the end of Friday, even if the flights took back to Heathrow.
The London Metropolitan Police said that anti -terrorism specialists had taken care of the investigations, “given the position of the subostation and the impact that this accident had critical national infrastructures”. At the same time, political leaders and experts in the sector said that it seemed very likely that the fire was an accident.
Both possibilities left the residents of Great Britain and global travelers have agitated.
If a harmful opponent can thus dramatically stop travel around the world causing a fire in an electricity plant in the neighborhood, it raises new concerns about the ability of open companies such as that of Great Britain to protect themselves from these non -traditional attacks.
And if the fire was the result of a weakness not detected in the basic infrastructure of the electric grid of Great Britain, the scope of the unleashed chaos could undermine the trust in the ability of the nation to correct the dilapidated systems at a time when finances are already stretched.
Prime Minister Keir Starmer and Sadiq Khan, the mayor of London, tried to reassure residents and travelers on Friday, with Mr. Khan who told Sky News in an interview that, despite the involvement of anti -terrorism officers in the investigation, there was no reason for no one to be worried or alarmed “.
However, neither the prime minister nor the mayor offered answers to some of the urgent questions posed by frustrated travelers, nervous neighbors of the airport and political officials across the country.
Why did the airport have not sufficient energy backups? Didn’t electric utility plan the possibility of such a fire, neither from sabotage nor technical malfunction? Do the main airports usually have backup systems that can power the entire operation or are they based on a main source of energy?
John McDonnell, a legislator that represents Hayes, the area in which the fire broke out, said that any investigation conducted in the days to come should have examined “because the backup agreements did not work”.
“There are lessons that must be learned here,” he told journalists on Friday afternoon.
On Friday in the early afternoon, the National Grid of Great Britain declared that the North Hyde sub -setting network, where the fire took place, had been reconfigured to restore power to the airport and the neighborhood, calling it a “temporary solution” while repairs begin. National Grid officials did not respond to an e -mail that requires information on the accident.
That announcement paved the way for a partial opening of the airport, where the first flights began again by landing within the evening.
“Now we will work with the airlines to repatriate passengers who have been diverted to other airports in Europe,” the airport officials said in a note. “We hope to perform a complete operation tomorrow.”
But even if Heathrow tries to return to normal operations, it remains a sense of uncertainty.
And Miliband, secretary of British energy, said in an interview on Friday soon with Sky News that the fire to the electrical substation that paralyzed Heathrow airport also eliminated at least one of the main backup systems designed to maintain energy in operation.
“There was a backup generator, but this was also influenced by the fire, which gives an idea of how unusual, unprecedented,” Miliband said.
The transformers convert the current from one voltage to another and are often filled with oil that acts both by insulating and refrigerant. The types of oil used can resist high temperatures, but they can turn on if they become quite hot.
In the case of the transformer near Heathrow, the experts said that he would turn 275,000 volts into 66,000 volts when apparently he was unable to. Jonathan Smith, vice commissioner for the London Fire Brigade, said that the fire involved “a transformer that includes 25,000 liters of cooling oil that was completely lit” to the following.
The inability of at least one backup system to quickly restore the power after such a serious interruption is probably at the center of the questions about the reliability of the British infrastructure in the aftermath of the fire and closure of the airport.
The British national infrastructure commission, which formulates the government recommendations on the main infrastructures, said that the fire had underlined the need for better preparation for shock and that operators build resilience in their systems and regularly lead stress tests.
“We clarified that the United Kingdom needs national resilience standards for our transport, energy, energy and water infrastructures,” said the president of the Commission, John Armitt, in a note. “These will clarify the operators and users on which levels of service should expect in the face of short and long term interruptions and we assure that regulators have a clear meter against which they can guarantee sufficient investments in resilience.”
In a post on social media, Willie Walsh, general manager of the Internazional Air Transport Association, a Global Trade Association of Airlines, wrote: “How it is that the critical infrastructure – of national and global importance – depends totally on a single source of energy without an alternative”.
“If so, as it seems,” he added, “then it’s a clear failure of the airport planning.”
In a statement, Heathrow airport said that the structure had “multiple sources of energy” but that there was no backup that would have provided enough energy to manage the entire airport, which said “uses the same energy as a small city”.
The declaration stated that the diesel backup generators and the little interruption power supplies have started that they would allow planes to land and passengers to land. But they would not have been enough to allow the airport to fully operate.
Simon Gallagher, a former manager of the largest British power supplier, said he believed that the subordination near Heathrow had been designed so that if the first transformer had a problem, a second could have quickly entered. “Basically, we have designed things so that something can fail” and the system can still continue working, he said.
But, he said, a number of things must have gone wrong, apparently allowing the fire to infuriate through the prevention systems and damage both transformers.
This is very unusual, said Gallagher, who is now the CEO of Uk Network Services, who advises customers the resilience of their electrical networks.
Gallagher said that the emergency generators systems mentioned in Heathrow’s declaration were designed to keep the track lights and the control tower systems operating even during an accident like the one that took place on Friday.
But he said it would have been impossible to continue on the ground, apart from an emergency, because there would have been no electricity to move the luggage, illuminate the terminals, manage doors and more. According to its estimate, doing all this would require at least 20 large diesel generators of the size of the 40 -foot shipping containers, each capable of generating a megawatt of power.
Heathrow does not have such a system, which would have been able to maintain power for the entire airport that flows for about six hours before having to be supplied with fuel, he said. But he added that other important energy customers, such as data centers, had installed large backup generators to guarantee energy in the event of an emergency.
“I think things will change,” Gallagher said. “I think Heathrow and other airports will install the backup generation.”