Back-up systems on Britain’s electricity network “worked well” in response to the major power cut that brought widespread disruption to the country, National Grid has said.
Almost one million people in England and Wales were cut off from electricity on Friday after issues with two generators.
Traffic lights stopped working, Newcastle Airport fell into darkness and Ipswich Airport was affected by the power loss incident.
Major disruption also hit the country’s railways during the busy Friday night commute.
Frustrated travellers continued to experience disruption to services at London’s Kings Cross station on Saturday.
Speaking to the BBC Radio 4 Today programme on Saturday morning, Duncan Burt, operations director at National Grid, said the power cut was an “incredibly rare event”.
Following the incident, the system was secured, and the Electricity System Operator gave the all clear to the Distribution Network Operators (DNOs), power companies who are responsible for supply at a local level, within 15mins, so that they could start to restore demand.
— National Grid ESO (@ng_eso) August 10, 2019
He explained that the two power stations disconnected from the grid “near simultaneously”.
Mr Burt said: “What happened then is our normal automatic response mechanisms came in to help manage the event, 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 added: “Those events happened very, very quickly, in a matter of a few seconds, maybe a couple of minutes maximum.
“That sequence of events is entirely automatic, we think that worked well, we think the safety protection systems across the industry on generators and on the network work well to secure and keep the grid safe.”
Professor Tim Green, co-director of the Energy Futures Laboratory, Imperial College London, previously said that he believed the two disconnected generators were at Little Barford and Hornsea.
He said: “This event does not appear to be due to wind generation reducing owing to reduced wind speed.
“If that were the case there’d be reduction across many wind farms in [the] same area.
“The first generator to disconnect was a gas fired plant at Little Barford at 16:58. Two minutes later Hornsea Offshore wind farm seems to have disconnected.”
Speaking to the BBC, Mr Burt said the power cut had “nothing” to do with changes in wind speed or the variability of wind.
He also said National Grid was “very confident” there was “no malicious intent or cyber attack involved” in the incident.
Mr Burt said National Grid is due to provide a “a detailed technical report” to Ofgem, which has already urgently demanded information as to what went wrong.
He added: “This will require careful study to make sure that we do learn any lessons that come out of it and that the next time this happens disruption is minimised and hopefully a lot less than it was last night.”
Around 300,000 UK Power Networks customers were affected in London and the South East, a spokeswoman previously said, and Western Power Distribution said around 500,000 people were affected in the Midlands, South West and Wales, with power restored to them all shortly after 6pm.
A spokeswoman for Northern Powergrid, which serves Yorkshire and the North East, said 110,000 of its customers lost power, while at least 26,000 people were without power in the North West of England, Electricity North West said.
Writing on Twitter on Saturday, the National Grid Electricity System Operator account said all demand had been reconnected by 5.40pm.
It added: “We appreciate the disruption caused and will continue to investigate, with the generators involved and wider stakeholders, to understand the lessons learnt.”
We appreciate the disruption caused by yesterday’s power outage and investigations have continued overnight to better understand the situation. As the Electricity System Operator we do not generate power directly, but use the power made available by industry to manage the system
— National Grid ESO (@ng_eso) August 10, 2019
In central London, trains began to run out of King’s Cross late on Friday night after the station was shut down amid “apocalyptic” rush-hour scenes across England.
Passengers were filmed forcing their ways through the barriers in an attempt to get themselves on to the first northbound service after services were halted for several hours.
One transport union leader has called on the Government to be be held to account for the power cut “fiasco”.
Manuel Cortes, general secretary of the Transport Salaried Staffs Association, said: “Having our rail network brought to a standstill in this way is totally unacceptable.
“We’ve seen thousands of passengers stranded, unable to board trains and a number of cancellations; others have been taken off trains and onto the tracks. We need to know why this occurred and the lessons to be learned.”