Nesco Faces Heatwave Cover-Up Allegations
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- Claire Coutinho, the shadow energy secretary, told parliament that Neso whistleblowers accused senior managers of ordering control room staff to skip normal note-keeping during the late June heatwave to avoid creating a full audit trail of grid strain.
- Neso spent almost £800,000 on payments to consumers to cut electricity use between mid-April and mid-July, per the Financial Times, after issuing summer emergency measures for the first time in the operator's history.
- Grid frequency fell to 49.66Hz on 23 June — below the 50Hz target but still above the 49.5Hz statutory limit — and hovered near the operational floor for nearly an hour, per data cited in the article.
- Neso issued an emergency call for 500MW of additional capacity from the Netherlands through the BritNed cable on 24 June and made a similar request to France, and was said to have breached normal limits on interconnector trading 'several times' that week.
- Eversheds Sutherland has been brought in to independently examine the allegations; Neso CEO Fintan Slye wrote to Ofgem saying the operator has "policies and procedures" to prevent such influence and would share findings with the regulator.
- National Grid sold Neso to the government for £630m in late 2024, a former employee noted, meaning engineers who once worried about a listed company's share price now face political pressure to balance a greener grid without 'a hiccup.'
Why it matters: If the cover-up claims hold up, the episode suggests Britain's state-owned grid operator prioritized political optics over operational transparency during the first ever summer emergency event — undermining the audit trail regulators rely on to prevent failure just as the country races toward Labour's 2030 clean energy target.
