UK blackout: MPs to question energy regulator's role

Official documents show Ofgem has known for 10 years that new safeguards are needed


The energy industry regulator is to be hauled before a committee of MPs to face questions over its role in last month’s blackout after official documents revealed it has known for a decade that new safeguards are needed.


A select committee plans to hold a hearing to press Ofgem on whether it has done enough update its regulation, which might have avoided last month’s “huge and widespread disruption”.


The business, energy and industrial strategy (BEIS) committee expects to hold the evidence hearing soon after parliament returns from prorogation in October.


Rachel Reeves, the chair of the committee, said: “Keeping the lights on and the country running is an essential job of government, and the business, energy and industrial strategy committee plans on pressing Ofgem, as well as ministers and the National Grid, to find out what went wrong.”


After years of industry talks Ofgem implemented some of its new rules three weeks after the blackout but others will not take effect until 2022.


The regulator’s archived consultation records show it has known since 2009 that thousands of small power stations may have “oversensitive” shutdown settings, which pose a serious risk to the energy system.


The UK’s highly attuned fleet of mini-generators, including renewable projects and diesel farms, played a key role last month in Britain’s biggest blackout in a decade, and in the last widespread outage in 2008.


The settings used to protect the equipment from electrical disturbances on the grid also make the plants more likely to shut down when there is a fault detected on the system. This makes it harder for National Grid, the network operator, to rebalance the system when there is an unplanned outage.


The unexpected shutdown of a gas power station and a windfarm last month triggered a domino effect of mini-outages which made it near-impossible to stabilise the grid, according to National Grid. In a report to Ofgem it suggested accelerating plans to update blackout safeguards.


Richard Black, the director of the Energy and Climate Intelligence Unit, said: “The industry has been aware of this for at least 10 years, and yet under current plans it won’t be fixed until 2022.


“What [the report] doesn’t say – because it’s a report to Ofgem – is that Ofgem as regulator has final responsibility for having allowed this fault to persist,” he said.


Reeves said the committee plans to “make sure that lessons have been learned” and that Ofgem is doing enough “to ensure the future resilience of the UK’s electricity grid, particularly given the changes coming about from the transition to a low-carbon energy system”.


Ofgem raised concerns over the smaller, “embedded” generators after the 2008 blackout and again in late 2017. It said that one power station fault could cause a cascade of outages at small-scale stations which automatically shut down if there are sudden changes to energy currents in the grid.


It warned that National Grid would be “potentially unable to protect against such a large loss”.


Britain is becoming more vulnerable to nuisance tripping from mini-generators because the frequency of energy currents running through the grid is becoming more volatile.


The Guardian reported last month that the grid’s frequency, which should remain at about 50Hz, fell to within 0.1% of its legal limit of 49.5 Hz three times in the three months before the blackout, for the first time in years.


The string of near-misses took place less than a year after a senior National Grid executive admitted the system operator is “walking blind” into the risk of blackouts because it cannot measure the energy system’s stability in real time.


An Ofgem spokeswoman said new regulations for small-scale power generators were being brought in this month.

“Significant changes have been made by industry and Ofgem to improve the resilience of Britain’s energy system following the power cuts of 2008. The causes of last month’s power cuts are complex. Ofgem and government will continue their investigations and will take any action necessary, alongside industry, to further improve the system’s resilience,” she said.


A government spokesman said: “The disruption caused to people and businesses by last month’s very rare power cut was unacceptable. That is why the secretary of state immediately ordered an investigation by the energy emergencies executive committee, which will report back imminently with its initial findings.”