THE amount of back-up electricity National Grid stores must be reviewed to avoid the type of power cut that hit 1.1million customers on August 9, the company itself has reported.
The energy operator said its systems had worked ‘in line with their design’ by automatically disconnecting some customers to save the network from complete collapse.
But it said the list of facilities hooked up to the disconnection systems must also be reviewed to ensure that no critical infrastructure or services are put at risk of an outage.
The blackout not only left more than a million households powerless for up to 45 minutes but caused chaos on some rail lines. Critical facilities affected included Newcastle Airport and Ipswich Hospital, which had a problem with its own back-up system.
National Grid said the failure arose after a lightning strike on a transmission circuit was followed by ‘almost simultaneous unexpected power losses’ at two plants. The level of back-up required by regulations did not cover the outage, so five per cent of users were cut off to protect the rest.
HOW CUT CHAOS UNFOLDED
Lightning strikes a transmission circuit at 4.52pm but systems operate correctly and normality is restored in around 20 seconds, with a loss of 150 megawatts.
Hornsea and Little Barford stations both immediately trip, causing the grid to lose another 981MW.
The lack of supply triggers a rapid fall in the frequency of the grid, causing another 350MW to disconnect in a defence mechanism to stop a collapse.
The back-up power of 1,000MW can’t cope with the extra pressure.
Just as the system seems to be righting itself, Little Barford trips again — bringing the total generation loss to 1,691MW.
The system cuts off five per cent of demand before another failure at Little Barford means the total loss is now 1,878MW.
Some 1.1million customers are without power for up to 45 minutes after the system disconnects 1,000MW of demand.
The system returns to normal by 4.57pm and all customers have their power back by 5.37pm.
Old Virgin uniforms to keep ruff sleepers cosy
OLD uniforms once worn by Virgin Trains staff have been turned into coats for dogs belonging to homeless people.
The rail operator donated the unwanted garments to be upcycled by prisoners in the textile factory at HMP Northumberland.
Coats, shell jackets, shirts and trousers have also been used to make blankets and scarves for human rough sleepers.
Items will be distributed by Virgin staff at London Euston, Birmingham New Street, Manchester Piccadilly, Liverpool Lime Street and Glasgow Central.
Charities will also be given them to pass on to the homeless.
Jo Buckley, Virgin’s community manager, said: ‘We set ourselves the challenge to be creative and socially responsible with disposing of these old uniforms. It’s a smart way to handle our waste.
‘It’s so rewarding to see the repurposed uniform benefiting those who really need a little warmth and comfort during the winter months.’
Employment at record high as wages surge
THE number of people in work has hit a record high, as wages increase at their fastest level in 11 years, new data shows.
The UK employment rate rose 31,000 to 32.78million in the three months to the end of July, the Office for National Statistics said. And the jobless rate hit a 45-year low of 3.8 per cent — falling 11,000 to 1.29million.
But the number of available jobs was at its lowest level since November 2017, dropping by 23,000 to 812,000. The ONS said it was being driven by fewer openings at small businesses.Wages rose 2.1 per cent year on year, taking account of inflation.
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