NESO Chief Executive Fintan Slye will no longer receive progress updates from the legal investigation into allegations surrounding the operation of Britain’s electricity system during June’s heatwave.
The change follows criticism that the inquiry could not be considered fully independent while senior executives were kept informed about an investigation involving claims against the organisation’s leadership.
The Times reports that revised terms of reference have removed Mr Slye from the process, despite an earlier version stating he and NESO Chairman Paul Golby, would receive regular progress updates unless a conflict arose.
NESO now says no member of its executive team will see the investigation’s findings until the work has been completed.
Law firm Eversheds Sutherland is examining allegations that operational records were altered or handled in a way designed to avoid freedom of information rules.
It is also investigating claims that members of NESO’s corporate affairs team interfered with control-room decisions as engineers worked to keep the electricity system stable during extreme heat on 23 June.
The allegations remain unproven and NESO has repeatedly said the system remained secure, customer supplies were not interrupted and all operational decisions were taken by authorised staff.
However, internal reports recorded five transmission safety limits being breached, with the largest exceeded by around 700MW.
A preliminary report written after the event stated that system constraints had been breached and system security compromised. NESO said the documents were genuine but represented an early assessment rather than its final conclusion.
The revised investigation process will allow staff to contact the legal team directly through a confidential email address and telephone line.
Whistleblowers have been told their identities will not be shared with NESO and the terms instruct staff not to alter, delete or overwrite records, including Microsoft Teams conversations and document histories.
Oversight will sit with a three-person panel including NESO Audit Committee Chair Jayne Scott, Ofgem Infrastructure and Security of Supply Director Akshay Kaul and Siobhán Duffy of UK Government Investments.
Mr Golby may still receive updates but only where the panel believes it is appropriate.
Shadow Energy Secretary Claire Coutinho had questioned the inquiry’s independence, after NESO publicly said employees would not be involved in, or updated on the investigation while its published terms allowed progress reports to senior leaders.
The issue has now moved beyond whether Britain came close to blackouts during the heatwave.
It is also testing whether the publicly owned system operator can demonstrate that allegations about its own management, record keeping and operational culture are being investigated without executive influence.
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