Price spike (three days, cap hit twice)
Mon 20 Jan · Tue 21 Jan · Wed 22 Jan
Research notes
Figures are for London unless they say otherwise.
What happened
London hit the 100p cap at 16:30 on both 20 Jan and 22 Jan; 21 Jan peaked at 81.1p (94.9p in Northern Scotland). Daily averages 38.5p, 33.1p and 45.2p. Overnight lows never fell below about 19p, so these were expensive all day.
Likely causes
- A wind drought. Transmission-metered wind averaged 2.5GW on 20 Jan, 3.2GW on 21 Jan and just 0.6GW on 22 Jan, touching 86MW at 08:30 that morning. Gas averaged 23 to 24GW on all three days and peaked at 26.7GW. (confirmed by source: grid data) Elexon FUELHH 20 to 22 Jan 2025
- Bloomberg, 21 Jan: UK day-ahead power hit £241.49/MWh, the highest in more than two years, with wind forecast to average 0.9GW on Wed 22 Jan, the lowest since Sep 2023, and record imports from Europe. (confirmed by source; article is paywalled, details taken from its headline, search summary and the syndicated report below) Bloomberg, 21 Jan 2025
- The same report gave a peak evening hourly price of £620/MWh and said low wind was pushing up prices across north-west Europe too. (confirmed by source) OilPrice.com, 21 Jan 2025
- Which day the £241.49 applies to: OilPrice words it as Tuesday's price, while Smart Energy UK's monthly report lists £241.49 on 22 Jan as January's highest. The auction was held on Tue 21 for delivery on Wed 22, and 22 Jan is the dearest of the three days in the Agile data, so it is almost certainly the 22 Jan delivery price. (inference, sources worded inconsistently) Smart Energy UK January 2025 report
- Nuclear output was down as well: about 3.5GW on 20 Jan against about 5.0GW on 8 Jan, so roughly 1.5GW of steady supply was missing. (confirmed by source: grid data; which reactors were off was not established) Elexon FUELHH 20 Jan 2025
- On 20 and 21 Jan GB was exporting nearly 3GW in the early hours despite having almost no wind, which suggests continental prices were even higher overnight. It fits the reports of a Europe-wide still, cold spell, and means GB could not lean on cheap imports. (inference from grid data)
- Drax describes Dec 2024 and Jan 2025 as two spells of "dunkelflaute" (cold, dark, still weather). Its write-up names 12 Dec and 8 Jan; it does not mention 20 to 22 Jan specifically. (confirmed by source, general context) Drax Electric Insights Q4 2024
Wider context that week
- European gas was dear: TTF rose through January on "cold and windless weather" and storage draws, on its way to a peak above €57/MWh on 11 Feb. NBP's January high was 133.9p/therm on 31 Jan. Elenger Q1 2025 gas market overview · Smart Energy UK
- Donald Trump was inaugurated on 20 Jan and signed the "Unleashing American Energy" order, which restarted US LNG export approvals, and declared a national energy emergency. S&P Global, 21 Jan 2025 · Congressional Research Service
- The calm ended abruptly: Storm Éowyn hit on Fri 24 Jan with record gusts in Ireland and 100mph-plus gusts in Scotland. Useful contrast for a post. Wikipedia: Storm Éowyn · Met Office Storm Éowyn summary (PDF)
Confidence
High for 21 and 22 Jan (Bloomberg plus grid data). Medium to high for 20 Jan: grid data shows the same conditions, but no report was found about that day by name.
Gaps
No NESO margin or capacity notice found for these dates. No weather-service write-up of the high pressure over the UK on 20 to 22 Jan was found; the "still, cold" description rests on the grid data and market reports. The reason for the lower nuclear output was not found. The Bloomberg article itself could not be opened.