Prices touch zero overnight
Research notes
Figures are for London unless they say otherwise.
What happened
London's minimum was 0.0p at 04:30, with an average of 15.3p and a peak of 41.0p at 18:30. All 14 regions reached 0p, none went below it. Highest anywhere was 46.6p in Northern Scotland.
Likely causes
- Strong overnight wind against low early-morning demand. The broker report for 13 Mar says "Elevated wind generation outperformed seasonal expectations again on Thursday and provided a substantial share of the supply mix", with day-ahead baseload at £56.44/MWh, low for a month when the front-month contract was near £97/MWh. The following report says wind averaged about 15.2 GW that week, "nearly double the week before". (confirmed by source for the windy week; that wind caused the 04:30 zero is an inference) Prestige, 13 Mar 2026, Prestige, 16 Mar 2026
- A Met Office yellow wind warning was in force on Thu 12 Mar in north-west England, with south-westerly gales of 39 to 47 mph continuing into the night. No named storm. (confirmed by source, but a local council page) Cumberland Council, 12 Mar 2026
- The price stopped at exactly 0p rather than going negative. Before 1 Apr 2026 a wholesale price of zero gave an Agile price of zero, so the wholesale day-ahead price probably bottomed at about £0/MWh. (inference)
Wider context that week
- This was two weeks into the Iran war. Brent settled above $100/bbl on Thu 12 Mar for the first time since 2022, NBP gas was about 126p/therm and the Strait of Hormuz was closed with QatarEnergy's LNG production shut down. Prestige, 13 Mar 2026
- On Mon 9 Mar the GB day-ahead daily average had hit €150.24/MWh, the highest since 15 Feb 2025, and TTF gas hit €56.45/MWh. So the week ran from a 13-month high to zero in four days. AleaSoft, 16 Mar 2026
- Nuclear output was reduced by outages at Hartlepool 2, Torness 2 and units at Heysham 1 and 2. Prestige, 13 Mar 2026
Confidence
Medium. The windy week is sourced, but nothing found speaks to the early hours of 13 Mar specifically.
Gaps
- No wind output figure for the night of 12 to 13 Mar. No press coverage of a zero price that day.