Overview
- The National Energy System Operator issued an electricity margin notice for Friday evening requesting 700 megawatts of extra generation between 7pm and 10pm as a precautionary buffer.
- Neso said forecasts show tight margins because very high temperatures across Britain and Europe are raising demand for cooling and constraining some generation.
- The Met Office reported a provisional June high of 36.7°C in Merryfield, Somerset and warned parts of the southeast could reach about 40°C, with rare red heat warnings in force.
- Market intervention has already been used this week, with analysis from Kraken showing Neso paid roughly £11 million on Tuesday to balance gas flows into the system.
- Extreme heat reduces output at some plants, cuts imports from strained continental supplies, and raises operating costs, which could increase short‑term generation payments and pressure on services like hospitals and transport.