Price spike (low wind)
Mon 2 Sep · Tue 3 Sep
Research notes
Figures are for London unless they say otherwise.
What happened
- Mon 2 Sep: London peaked at 38.6p at 18:00, average 21.1p, lowest 15.3p at 03:30; highest anywhere 43.8p in Northern Scotland.
- Tue 3 Sep: London peaked at 36.1p at 18:30, average 20.7p, lowest 15.2p at 02:30; highest anywhere 40.8p in Northern Scotland.
Likely causes
- Mon 2 Sep, 18:00 (London's peak): wind 8.1GW (22% of supply), solar 0.6GW, gas 14.7GW (40%), imports 3.3GW, total supply 36.5GW. Over the day wind averaged 4.8GW; the 2024 average was 9.4GW (29%). Source: NESO historic generation mix. (figures confirmed by source; link to prices is inference)
- Tue 3 Sep, 18:30 (London's peak): wind 3.8GW (11% of supply), solar 0.6GW, gas 16.6GW (47%), imports 4.3GW, total supply 35.7GW. Over the day wind averaged 3.9GW; the 2024 average was 9.4GW (29%). Source: NESO historic generation mix. (figures confirmed by source; link to prices is inference)
- Wind was less than half its yearly average at the peak on Tue 3 Sep (3.8GW, against 9.4GW for the year), so gas made up the gap. (inference from NESO data)
- The peak came in the early evening on Mon 2 Sep and Tue 3 Sep, when demand is highest and there is no solar. (inference)
- Elexon market index: Mon 2 Sep averaged £93.39/MWh with a high of £123.04 at 06:30; Tue 3 Sep averaged £86.41/MWh with a high of £105.44 at 07:30. Source: Elexon market index, Mon 2 Sep. (confirmed by source; a short-term index, not the day-ahead auction Agile follows)
Wider context that week
- Nothing notable found for that week.
Confidence
Medium. The grid figures fit the prices, but no report found names a cause for this date.
Gaps
- No news report or official write-up found that ties this date to a cause; the causes above are from the data.