Overview
- The National Energy System Operator issued an electricity margin notice for Thursday evening between 6.30pm and 10.30pm, asking generators and flexibility providers to make extra capacity available.
- Neso warned its forecasts show tight margins for the peak period and reported a developing supply gap of roughly 1.2 gigawatts that it wants industry to close.
- The operator stressed the notice does not mean blackouts are imminent and that similar June callouts were cancelled once margins improved.
- Low wind output, reported around 6.6 percent of the mix, and reduced nuclear exports from France because cooling waters have warmed have increased reliance on gas, domestic nuclear and imports.
- The episode highlights a growing pattern of summer grid stress as extreme heat raises air‑conditioning use and reduces generation efficiency, a trend that could make short, targeted margin notices more common.