Negative prices (Storm Henk)
Mon 1 Jan · Tue 2 Jan
Research notes
Figures are for London unless they say otherwise.
What happened
- Mon 1 Jan: London was below zero for half an hour from 04:30, min −2.4p at 04:30; average 11.6p, peak 32.8p at 16:30; all 14 regions at 0p or below; lowest −2.9p in Northern Scotland.
- Tue 2 Jan: London was below zero for 1.5 hours (longest spell half an hour from 00:00), min −1.9p at 00:00; average 13.6p, peak 31.7p at 16:30; all 14 regions at 0p or below; lowest −2.3p in Northern Scotland.
Likely causes
- Storm Henk affected the UK on 2 Jan 2024, according to the Met Office's list of named storms for 2023/24. Source: Met Office, UK storm season 2023/24. (confirmed by source; its link to the prices is inference)
- Mon 1 Jan 2024 was the New Year's Day bank holiday. Source: GOV.UK bank holidays. (confirmed by source)
- Mon 1 Jan, 04:30 (London's lowest half-hour): wind 14.9GW (57% of supply), solar 0GW, gas 2.7GW (10%), imports 2.1GW, total supply 26.3GW. Over the day wind averaged 13.6GW; the 2024 average was 9.4GW (29%). Source: NESO historic generation mix. (figures confirmed by source; link to prices is inference)
- Tue 2 Jan, 00:00 (London's lowest half-hour): wind 18.5GW (64% of supply), solar 0GW, gas 2.6GW (9%), imports 1.4GW, total supply 29.1GW. Over the day wind averaged 13.3GW; the 2024 average was 9.4GW (29%). Source: NESO historic generation mix. (figures confirmed by source; link to prices is inference)
- Wind was well above its yearly average at the lowest half-hour on Tue 2 Jan (18.5GW, against 9.4GW for the year). (inference from NESO data)
- The low came overnight on Mon 1 Jan and Tue 2 Jan, when demand is at its lowest. (inference)
- Mon 1 Jan was a bank holiday (New Year’s Day), when demand is lower. (inference)
- Elexon market index: Mon 1 Jan averaged £51.68/MWh with a low of −£20.16 at 23:30; Tue 2 Jan averaged £49.17/MWh with a low of −£16.93 at 00:00. Source: Elexon market index, Mon 1 Jan. (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
High.
Gaps
- None beyond what is said above.