Negative prices (Storm Jocelyn)
Research notes
Figures are for London unless they say otherwise.
What happened
- Wed 24 Jan: London was below zero for 1 hour from 03:30, min −1.9p at 03:30; average 12.3p, peak 29.3p at 17:30; all 14 regions at 0p or below; lowest −2.2p in Northern Scotland.
Likely causes
- Storm Jocelyn affected the UK on 23 and 24 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)
- Wed 24 Jan, 03:30 (London's lowest half-hour): wind 18.8GW (62% of supply), solar 0GW, gas 4.6GW (15%), imports 1.7GW, total supply 30.1GW. Over the day wind averaged 17.1GW; 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 Wed 24 Jan (18.8GW, against 9.4GW for the year). (inference from NESO data)
- The low came overnight on Wed 24 Jan, when demand is at its lowest. (inference)
- Elexon market index: Wed 24 Jan averaged £52.81/MWh with a low of £6.24 at 03:30. Source: Elexon market index, Wed 24 Jan. (confirmed by source; a short-term index, not the day-ahead auction Agile follows)
Wider context that week
- Electric Insights: wind produced more than seven-tenths of demand for the first time on 26 Jan 2024. Source: Electric Insights, Power system records (Q1 2024). (confirmed by source)
- Storm Isha (Sun 21 Jan to Mon 22 Jan) was within a few days of it. Source: Met Office, UK storm season 2023/24. (confirmed by source; its effect on these prices is inference)
Confidence
High.
Gaps
- None beyond what is said above.