- Ofgem has promised anonymity to whistleblowers in an investigation into claims of near-miss blackouts on the grid.
- It is alleged that senior officials at the National Energy System Operator (Neso) attempted to cover up the blackout risk during last month’s heatwaves.
- On June 23, the grid fell below safe operating limits for multiple periods, leading to significant operational challenges.
- Internal reports indicate that five safety limits on Britain’s electricity grid were breached during the heatwave, with the largest breach reaching 700MW.
- Neso has engaged Eversheds Sutherland to conduct an internal investigation into the claims of a near-miss blackout.
- Ofgem will provide active regulatory oversight of the independent investigation and has ordered a separate regulatory review.
- On June 23, the grid's frequency fell as low as 49.67Hz and repeatedly dropped below operational limits due to high demand and low wind generation.
- Neso issued an emergency instruction to stop exporting 800MW of electricity to the Netherlands and requested 500MW of emergency assistance from France.
- A whistleblower claimed that during the incident, there was no available pre or post-action mitigation options, leading to a critical situation.
Ofgem is investigating the National Energy System Operator (Neso) for allegedly covering up blackout risks during a heatwave in June, where safety limits were breached multiple times. The regulator has promised anonymity to whistleblowers, allowing them to report concerns without fear of reprisal.1256
Reports indicate that on June 23, the grid fell below safe operating limits for “multiple periods,” with five safety limits breached, compromising system security. A whistleblower stated, “We had not 1MW left to instruct, frequency response was depleted due to the prolonged unsafe low frequency and one fault on the transmission network or generation side would then cause a full blackout. It was unprecedented.”347
Neso has engaged independent investigators from Eversheds Sutherland to conduct the inquiry, which Ofgem will oversee. An Ofgem spokesman emphasized the importance of transparency, stating, “Confidence in the operation of Great Britain’s electricity system depends not only on the resilience of the system itself but also on confidence that serious concerns are investigated rigorously and independently.”
Despite the allegations, Ofgem maintains that the electricity system operated reliably throughout the heatwave. However, internal reports contradict this, revealing that system constraints were breached, with one report noting a breach of up to 700MW. The frequency fell as low as 49.67Hz, prompting emergency measures including halting exports to the Netherlands and requesting assistance from France.
Ofgem is also commissioning a separate review to assess whether any rules were broken during the incident, highlighting the need for accountability and improved system security.
“Ofgem has also ordered a separate post-event regulatory review to determine if rules were broken. A whistleblower claimed the grid had no megawatt left in reserve and a single fault could have caused a full blackout, while internal reports show five constraint breaches up to 700MW.”
GB News
The Times
