Three energy companies will pay a combined £10.5m for failing to prevent a power cut after a lightning strike last summer that left more than 1 million customers in the dark and led to travel problems across large parts of the UK.
The energy regulator, Ofgem, said Hornsea One, a windfarm company part-owned by Ørsted, and RWE, the owner of a gas power station, had each agreed to pay £4.5m for not remaining connected after the lightning strike.
UK Power Networks, a Hong Kong-owned company that runs distribution networks in the east of England, south-east England and London, will pay £1.5m for not following correct procedures. The money will go into Ofgem’s consumer redress fund.
Large parts of England and Wales were affected by the power cut on the evening of 9 August, which caused massive disruption during rush hour as railway stations fell into darkness and traffic lights turned off.
A lightning strike on that Friday evening caused the Hornsea windfarm off the coast of Yorkshire and RWE’s Little Barford gas power station in Bedfordshire to stop generating electricity because of “unforeseen technical issues”. The strike also put offline about 150MW of smaller generation, known as distributed generation. National Grid electricity system operator (ESO), which manages the distribution of power in the UK, activated backups but there was not enough available, meaning local network operators were forced to cut off customers.
Power was restored within 45 minutes but the disruption on the railway network lasted well into 11 August.
The Office of Rail and Road, a separate government regulator, found train operating companies had also contributed to the disruption, which resulted in King’s Cross and Euston stations in London being closed. Software flaws on some trains caused extended delays for many commuters.
ORR’s report criticised Govia Thameslink Railway and the train manufacturer Siemens, but said there was no breach of regulations that would warrant a fine. Twenty-two GTR trains required technicians to restart them after shutting down automatically when the power failed. There were too few technicians on standby to handle the number of stranded trains, while Siemens admitted the software on the trains was flawed.
Ofgem also said it would review the structure and governance of National Grid ESO after raising concerns about its response. A National Grid ESO spokesman said the report confirmed there was “no link between our actions and the power cut of 9 August”, and said many of Ofgem’s recommendations were contained in its own review.
However, Jonathan Brearley, Ofgem’s executive director for systems and networks, said the investigation had “raised important questions” about National Grid ESO.
He added that it was right the energy companies had paid up because of the “disruption and distress” the power cut had caused.
The government-backed energy emergencies executive committee also published plans on Friday to reduce the chances of similar blackouts happening again. The business secretary, Andrea Leadsom, confirmed its action plan would be implemented in full and described the power cut as “unacceptable”.
Plans include reviewing the benefits and drawbacks of requiring National Grid ESO to hold additional backup generation, and supporting essential service owners and operators to put in place more robust business continuity plans.
Ørsted, RWE and UK Power Networks said they had all taken steps to rectify the problems.
Steve White, the chief operating officer of GTR, said: “Passengers are now protected from this rare but disruptive event because, following a full review with GTR, Siemens Mobility has modified all the trains so that none of them now need a technician to restart.”
