The National Energy System Operator (NESO) has commissioned an independent investigation into whistleblower allegations that staff were instructed to hide evidence of system failures during June’s heatwave.
The move follows concerns raised in Parliament by Shadow Energy Secretary Claire Coutinho amid claims operational decisions were influenced to protect the organisation’s reputation.
Coutinho has alleged grid bosses were “risking blackouts to protect Neso’s reputation”.
The allegations include claims that staff were told to stop recording how key operational decisions were made during periods of system stress and that corporate affairs staff sought to influence control room decisions.
While welcoming the inquiry, Ms Coutinho questioned its independence, saying: "I'm glad Neso have launched an investigation. However, why is this not being run by Ofgem or the Department for Energy (who we've heard nothing from throughout)?"
She added: "Who is setting the terms of reference? If it is Neso leadership and, for example, they restrict who is spoken to as part of the investigation, then that is deeply problematic."
NESO said the investigation would be carried out by an external law firm reporting to the chair of its audit and risk committee.
It also stressed that the electricity system "operated securely" throughout the heatwave, adding: "No customer demand was disconnected, frequency and voltage remained within statutory limits, and no lines or cables were overloaded."
The organisation said it is also carrying out a routine review of system and market operations during the period. It added that an independent investigation into the allegations around decision-making and record-keeping had been commissioned and that "Its conclusions will be published."