Peterhead power station, paid to guarantee it can help keep the lights on, fails to function properly during testing
Britain’s plans to keep the lights on this winter have been thrown into fresh doubt after a power plant supposed to provide back-up electricity supplies failed during testing.
The Peterhead gas-fired station in northern Scotland was unable to generate power as expected during a test last week, it has emerged.
The plant, owned by energy giant SSE, was one of three power stations handed a contract last month by National Grid to be paid to guarantee they could fire up if needed, as part of emergency measures to prevent blackouts.
The plans were drawn up after a series of power plant closures eroded Britain’s spare electricity generation capacity – the safety buffer between peak supply and demand – to wafer-thin levels.
The three back-up power plants recruited under the emergency plans were supposed to guarantee they would be available if required between 6am and 8pm on weekdays from November to February.
But Peterhead, a 32-year old plant with 780-megawatt capacity, unexpectedly failed to produce required power levels last Thursday during a monthly “proving” test.
“We are in the process of discussing what did go wrong,” a spokesman for National Grid said.
Both SSE and National Grid declined to disclose details of the fault or to confirm whether it had now been fixed.
Dan Lewis, senior energy policy adviser at the Institute of Directors, said the failure was “worrying”.
“There’s just no margin for error,” he said. “When we are up against tighter and tighter margins inevitably things start to trip up. You don’t need many cold days to put yourself in a difficult position.”
One industry source claimed Peterhead had simply failed to generate power at all during the test, while Utility Week, which first disclosed the failure, reported that power unexpectedly dropped from 780MW to zero, citing National Grid data.
“They should have awarded the contract to a more reliable plant,” one UK power trader told the publication.
National Grid’s spokesman said the company did not recognise the specific power output figures cited by Utility Week.
But they added: “The reason to do tests is to ensure this kind of thing doesn’t happen when you actually need them.”
National Grid’s spokesman added that SSE could face penalty charges if Peterhead “doesn’t function as it should”.
The disclosure of the problem at Peterhead highlights the fragility of Britain’s energy system heading into this winter as its ageing power plant fleet suffers unexpected shutdowns.
Peter Atherton, energy analyst at Liberum Capital, described the test failure as “embarrassing”.
Britain’s tight capacity margins mean “you can’t have many things go wrong,” he said.
Peterhead had functioned as expected in a previous test earlier this month. The two other power plants recruited to the scheme have also both been functioning in recent weeks.
As well as the back-up power plants, National Grid has also brought in emergency measures to pay industrial businesses to power down or switch to diesel generators from 4pm to 8pm on winter weekdays.
Fires at Ferrybridge and Ironbridge power plants had already eroded Britain’s spare capacity more than had been expected this winter and safety outages at four nuclear reactors worsened the situation.
However, two of the four nuclear reactors have now resumed operation with a third due to do so in coming days.
A spokesman for the Department of Energy and Climate Change said: “This Government has a plan to keep the lights on now, and into the future, thanks to the new powers we have given to National Grid and investment in the UK’s energy infrastructure.
“National Grid undertakes these proving tests in order to be certain that plants are able to provide extra generating capacity when called upon.
“Peterhead is one of three plants who have been contracted to provide extra generation over the winter months if needed, while a number of other power units which were previously out of service have also begun the process of resuming generation.”