This last blackout appears to be under control.As always we will hear the official press release on MSM which will be a distance from the truth.
UK Power Networks tweeted on Friday evening: “We’re aware of a power cut affecting large parts of London and South East. We believe this is due to a failure on National Grid’s network, which is affecting our customers.”
Western Power Distribution (WPD), the electricity distribution network operator for the Midlands, south-west and Wales, said there was a “major incident”.
It said on Twitter: “We are currently experiencing a major incident on the national electricity infrastructure. We are in the process of restoring customers now and will provide further updates as soon as possible for specific areas. We are sorry for the inconvenience this is causing.”
Power outages in the UK today in the North: Live: 100,000 homes left without power following 'high voltage' incident
And also London and the South East: Major power cut hits large parts of England and Wales
“Our normal automatic response mechanisms came into help manage the event,” 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 was confident it had not been not a malicious or a cyber attack, he added.
While the system returned to normal on Friday night, disruption was expected to continue into Saturday with rail operators saying trains had not ended up in their correct destination meaning services would still be affected.
Ofgem’s powers under the Electricity Act, which it will use to conduct the investigation, allow it to impose penalties up to a maximum of 10% of the regulated companies UK turnover.
National Grid reported annual revenue, or turnover, of 14.9 billion pounds ($18 billion) for the year to March 31, 2019.
An hour-long outage on the evening of Aug. 9 cut off one million electricity customers, including homes, businesses, one hospital and Newcastle Airport and caused disruption on the rail network.
National Grid said the power cuts were the result of an unusual issue that led to the almost simultaneous loss of output from two generators - Orsted’s Hornsea off-shore windfarm and RWE’s Little Barford gas-fired plant.
There were many lightning strikes that hit the electricity grid that day, but only one had a significant impact - on a transmission line at 1652 local time, which returned to normal operation after around 20 seconds, the grid’s report said.
Around 500 megawatts of generation capacity was also disconnected - all of which is normal for such events.
However, immediately after the lightning strike and within seconds of each other, Hornsea and Little Barford reduced supply to the grid, disconnecting 1,378 MW of generation.
“As generation would not be expected to trip off or de-load in response to a lightning strike, this appears to represent an extremely rare and unexpected event,” National Grid said.
“This unexpected loss of generation meant that the frequency fell very quickly and went outside the normal range of 50.5Hz – 49.5Hz,” it added.
Back-up power and other tools were used but the size of the generation loss meant the frequency fell to 48.8Hz which is a level at which secondary backup systems were required to disconnect some demand to ensure the safety of the network.
This, along, with additional generation, returned the system to normal by 1706 and network operators started to returned supply to customers by 1737, the report said.
National Grid said it will deliver its final report to Ofgem by Sept. 6, in which it will examine the exact failure mechanisms at Little Barford and Hornsea, as well as demand side impacts and communication processes.
Separately, an emergency committee will also investigate the incident, the government said last week.