Ofgem reviews electricity system performance following June extreme heat events
The energy regulator is examining how the electricity network performed during a period of high temperatures earlier this year to ensure future system security and stability.
Key points
- Ofgem is investigating electricity system operations and decision-making during the extreme heat experienced in late June 2026.
- A separate independent report into working culture and record-keeping at the National Energy System Operator (NESO) has also been published.
- Final conclusions from the regulator regarding system security standards are expected to be published by the end of January 2027.
Ofgem has received a preliminary report from the National Energy System Operator (NESO) detailing electricity network events that took place during the week beginning 22 June 2026. This review follows a period of extreme heat and aims to assess whether the system functioned as required.
The regulator is now examining operational planning, demand forecasting, and market responses. This process will involve technical analysis and further discussions with industry stakeholders over the coming months to determine if security standards were properly maintained during the heatwave.
Scope of the investigation
Ofgem’s inquiry is currently focused on how the electricity system was managed during the heatwave. The review will look at balancing services, the availability of power generation, and how interconnectors flowed during the period. The regulator has stated that it has not yet reached any formal conclusions or regulatory judgements regarding the actions taken at that time.
Whistleblowing and culture review
Alongside the technical system review, the findings of an independent investigation by Eversheds Sutherland have been released. This report addresses whistleblowing allegations regarding operational decision-making and record-keeping practices at NESO. Ofgem participated in the panel that oversaw this investigation to ensure it remained independent and objective.
The NESO Board is now considering the findings of this separate investigation and will develop a plan to address the issues raised about its working culture.
Next steps for the regulator
Ofgem expects to release its final conclusions on the security of the electricity system no later than 31 January 2027. Following this, the regulator intends to publish a plan of action by 31 March 2027. If the inquiry identifies any failures to meet regulatory obligations, Ofgem may consider opening formal enforcement investigations into those involved.
What it means for you
- There is currently no change to your energy supply or service as a result of these investigations.
- Households do not need to take any action regarding these regulatory reviews.
Sources
We compared these reports before writing and checked every figure, date and name in this story against them. Read them for the full detail.
- Ofgem: Update on the Independent Eversheds investigation and Ofgem’s technical review of energy system operations during extreme heat (19 Oct)
Spotted a mistake? Email [email protected]. This story is based on the reports above and its facts were checked against them; it is not financial advice.
