When critical decisions live in Word and Excel: lessons from the UK grid operator review

In 2026, Britain’s electricity system operator, NESO, was the subject of an independent investigation into whistleblower allegations about how it kept records during a period of grid stress. The investigation found no evidence to substantiate the core allegations, but it still identified governance and control issues worth addressing. The lesson travels well beyond the energy sector.

What was alleged

Whistleblowers told a former shadow minister that, during periods of system stress in June 2026, senior managers instructed control-room operators to keep “live documents” with no version history, and that this was intended to leave no audit trail available to Freedom of Information requests. Separate claims alleged that corporate affairs staff had interfered in operational decisions around a frequency incident on 23 June 2026 (NESO terms of reference, via LexisNexis).

What the investigation found

NESO commissioned the law firm Eversheds Sutherland to investigate independently, overseen by a panel that included representatives from Ofgem and UK Government Investments. The firm interviewed 36 witnesses across functions and seniority levels. It found no evidence of inappropriate influence over operational decisions, and no evidence that control-room records were altered, inappropriately managed or concealed to avoid public scrutiny (NESO).

The investigation did not stop there. It identified governance, cultural and control issues that NESO should still address — particularly how staff raise concerns, how those concerns are heard, and how feedback is given back to them. NESO said it accepted the recommendations in full and that its Board would oversee an implementation plan. Ofgem’s own, broader technical review of system conditions during the June 2026 events remained open at the time of writing, with conclusions due no later than 31 January 2027 (Ofgem).

To be accurate about what this case does and doesn’t show: the investigation did not find evidence of a cover-up. It found an organisation with record-keeping practices — “live documents” without version history — that could not, on their own, prove after the fact that nothing had been altered. That gap is the lesson.

The lesson for any critical process

Nobody has to be acting in bad faith for a lack of audit trail to become a liability. A shared working document with no version history can’t prove what it contained an hour ago, whether it’s a control-room log, a formulation sheet, or a month-end consolidation. The fix isn’t a new system managers have to learn under pressure — it’s a governed record on top of the document people already use:

• Every change recorded automatically — who, what and when — without relying on someone to remember to log it.
• No silent overwrites. A value is replaced, not erased; the previous value stays on record.
• Evidence ready before it’s requested, not reconstructed under pressure when an investigation starts.

This is the same control IT-TIDY applies to spreadsheets running finance, quality and operations processes. See how it works, or read how this compares to EUC risk tools built for banking compliance that stop at inventory instead of active control.