Britain’s electricity system operator has been cleared of allegations that senior figures improperly influenced control room decisions or manipulated records – but an independent investigation has exposed deep concern among engineers about whether the grid can be managed securely as the power system changes.
The Eversheds Sutherland investigation found no evidence that National Energy System Operator staff altered or concealed control room records to avoid scrutiny and no evidence that corporate affairs staff improperly interfered with operational decisions.
NESO has seized on those conclusions, saying the central allegations made against the organisation were unsubstantiated.
But the same report paints a much more uncomfortable picture of life inside the control room, including high levels of stress, a significant disconnect between engineers and senior management and concern among some staff that operational warnings are not always being heard strongly enough.
Former Shadow Energy Secretary Claire Coutinho, who is now Shadow Business Secretary, said NESO still had serious questions to answer despite being cleared of the specific misconduct allegations.
She commented:
It is extraordinary that NESO’s takeaway is that the core allegations made by the whistleblowers are unsubstantiated.
“As I’ve always said, the core allegation is that the electricity grid is not being run securely. In that respect, the Eversheds report is utterly damning.”
Fragmented culture
Eversheds found “high levels of stress and concern” within the Electricity National Control Centre about the future ability to keep supply and demand balanced, as the system becomes more dependent on renewable generation.
The report also identified what it called a “significant disconnect” between control room staff and NESO’s executive leadership, with some engineers feeling senior managers did not fully understand the realities and pressures of operating the system.
Those concerns became particularly acute during the extreme heat of 23 June.
NESO publicly maintained at the time that the electricity system was not at risk but Eversheds heard evidence that some control room staff felt this did not reflect their experience inside the control centre.
The report records concerns from engineers that the system had been outside normal operational limits for several hours while staff worked continuously to restore balance. That is not the same though, as saying statutory security limits were breached or that blackouts were imminent.
Ofgem scrutiny
The separate preliminary technical review commissioned by Ofgem found system frequency remained within the statutory range of 49.5Hz to 50.5Hz throughout the June event and no customers were disconnected.
Ofgem is now looking into the whole incident and has not yet reached its final judgement on whether the system remained secure, or whether all operational requirements were followed.
Its inquiry is continuing into system security, forecasting, operational decision-making, inter-connector flows, generation availability and the response of balancing services and the wider market.
Ms Coutinho said the cultural findings meant the report should not be read simply as a clean bill of health.
She said: “There are multiple serious problems highlighted – from a culture of managers only wanting to hear ‘good news’, to poor record keeping and, most concerningly, a reluctance to action complaints from engineers because of the need to ‘keep stakeholders happy’.”
Eversheds did not substantiate allegations that management deliberately altered records or directed operational decisions for political or reputational reasons.
It did, however, identify a culture of what it described as reputational sensitivity and recommended changes to the way concerns are escalated, recorded and dealt with.
NESO response
The investigation has cleared individuals and the organisation of the specific allegations it was asked to examine – but it has also found enough concern about culture, communication and record keeping, for NESO to accept every recommendation – and commit to an improvement plan overseen by its board.
NESO Chair Paul Golby said: “The investigation’s findings are clear that there was no evidence to substantiate any of the allegations around inappropriate influence over decision making or inappropriate record keeping processes.
“The Board will oversee the development of plans to address the issues raised in the report and ensure these are implemented as a matter of urgency.”
Chief Executive Fintan Slye also accepted the need for change, saying: “It is constructive in identifying areas where we could improve how colleagues can raise concerns and how we respond to them. I want all colleagues at NESO to feel heard.”
Heatwave highlights weakness
The June event remains the bigger unresolved question.
Extreme heat increased electricity demand while parts of Europe were also experiencing difficult system conditions. NESO had to manage tight margins, changes in interconnector flows and periods when operational limits were under pressure.
Its own preliminary technical report says frequency remained within statutory limits, while Chief Operating Officer Kayte O’Neill said control room engineers did an “outstanding job” and ensured no customers were disconnected.
There is therefore an important difference between what has now been settled and what has not. The allegation that records were deliberately manipulated or that corporate affairs staff improperly overruled engineers has not been substantiated.
But whether Britain’s electricity system was operated securely throughout the June heatwave, whether the current framework is robust enough for a system increasingly dependent on renewables – and whether control room engineers are being listened to when they raise concerns, remain important questions.
Ofgem’s final technical conclusions will now carry considerably more weight than NESO’s internal response.
Until those are published, the Eversheds report closes one part of the controversy but it does not close the wider debate – about how securely Britain’s rapidly changing electricity system is being run.
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