LONDON • Energy regulators yesterday demanded an urgent report from the operator of Britain's electricity grid into what caused a power cut that led to chaos across the country, with trains brought to a standstill and traffic lights knocked out.
The outage on Friday evening left almost one million homes without power. Two of London's busiest train stations, Euston and Kings Cross, closed at rush hour because of overcrowding as services were cancelled or delayed.
A hospital in the eastern town of Ipswich said its back-up generator had failed, while the cut also hit the airport and metro system of the city of Newcastle in north-east England.
"Ofgem (the Office of Gas and Electricity Markets) has asked for an urgent detailed report from National Grid so we can understand what went wrong and decide what further steps need to be taken," the energy watchdog said in a statement. "This could include enforcement action."
National Grid, which owns the electricity transmission system in England and Wales, said there had been a rare and unusual issue which had led to the almost simultaneous loss of power from two generators.
"Our normal automatic response mechanisms came in to help manage the event," Mr Duncan Burt, National Grid's operations director, told BBC radio. "But the loss of power was so significant that it fell back to a set of secondary back-up systems which resulted in a proportion of electrical demand across the country being disconnected for a short period to help keep the rest of the system safe."
He said that action meant power to the vast bulk of the country had been maintained but he said they appreciated the disruption the outage had caused to others.
"We will want to look at that automatic chain of events," he said.
National Grid would provide Ofgem with a detailed, technical report into the incident, but is confident it had not been a malicious or a cyber attack, he added.
Industry experts believe the blackout was prompted by a gas-fired power station in Bedfordshire, north of London, and then an offshore wind farm in Yorkshire, northern England, both disconnecting from the grid.
The outage lasted for several hours, affecting around 300,000 customers in London and the south-east, and 500,000 in the Midlands, south-west England and Wales, according to regional power utilities.
Some 110,000 were affected in Yorkshire and north-east England.
RESTORATION PLANS CRUCIAL
This is perhaps a reminder that, even though we have never suffered a whole system blackout in Britain... restoration plans always need to be kept under review.
DR KEITH BELL, a professor of electronic and electrical engineering at the University of Strathclyde. He said the power cut was a "relatively small event" compared with blackouts seen elsewhere in the world.
It sparked rush-hour transportation misery, as some traffic lights faltered on the capital's streets and air traffic was disrupted at the airport in Newcastle.
"All the traffic lights were down, but there were no police present... It was like witnessing something out of an apocalyptic film," Ms Harriet Jackson told Britain's Press Association in south London.
Members of the public posted images on social media, which showed the Tube network in darkness and people having to use their mobile phones as torches.
The power cut added a moment of darkness to months of political drama over the country's exit from the European Union.
"Was that #powercut someone attempting to fix Britain by turning it off and on again?" joked Twitter user Emma Clarke.
"Country having a practice for no deal Brexit #powercut," joked another Twitter user, referring to the potential economic disruption if the country leaves the European Union at the end of October without a withdrawal deal.
Many trains were delayed or cancelled on Britain's national rail network, with efforts to return services to normal hampered by severe weather yesterday.
Dr Keith Bell, a professor of electronic and electrical engineering at the University of Strathclyde, said the power cut was a "relatively small event" compared with blackouts seen elsewhere around the world.
"This is perhaps a reminder that, even though we have never suffered a whole system blackout in Britain... restoration plans always need to be kept under review," he added.
REUTERS, AGENCE FRANCE-PRESSE