Ofgem has ordered two investigations into the operation of Britain’s electricity system during June’s extreme heat, including a separate independent inquiry into whistleblowing allegations involving the National Energy System Operator.
The regulator said NESO managed periods of high demand and lower generation during record temperatures, with no disruption to customer supplies and no concern over whether electricity demand could be met.
However, Ofgem said allegations about operational decision making and record keeping must be examined fully to maintain confidence in the way the power system is run.
It has used its regulatory powers to commission NESO to carry out an in-depth review of operational activity during the heatwave.
The analysis will examine weather conditions, the state of the electricity system and the decisions taken by operators during the period of extreme heat.
It will also assess whether NESO complied with relevant security standards and identify any lessons that could strengthen system resilience in future periods of high demand, or constrained generation.
Alongside that work, Ofgem will oversee a separate independent investigation into specific whistleblowing concerns raised about operational decision making and record keeping at NESO.
The regulator said both reviews must be carried out thoroughly, objectively and transparently.
Recent heatwaves have placed additional pressure on Britain’s energy system, with higher temperatures increasing electricity demand while also affecting the availability and performance of some generating assets.
NESO is responsible for balancing supply and demand across Great Britain in real time and ensuring the electricity system continues to operate securely.
Ofgem stressed that Britain’s security of supply remained strong throughout June and the system operated reliably as designed.
It said there was no disruption to customers and no point at which officials were concerned that electricity demand could not be met.
The investigations will instead focus on how the system was operated, whether all procedures and standards were followed and whether concerns raised by whistleblowers were properly recorded and addressed.
Ofgem said confidence in Britain’s electricity system depends not only on its physical resilience but also on trust that serious operational concerns are investigated independently.
The regulator added that reviewing incidents and operational decisions is essential to improving security as extreme weather places increasing pressure on the energy system.
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