Energy was last better‑than‑free: yesterday Next

Research notes

Figures are for London unless they say otherwise.

What happened

• Mon 29 Aug: London peaked at 78.0p at 00:00 (Agile's 78p cap), average 78.0p, lowest 77.7p at 03:30; highest anywhere 78.0p in Eastern England.
• Tue 30 Aug: London peaked at 78.0p at 00:00 (Agile's 78p cap), average 78.0p, lowest 78.0p at 00:00; highest anywhere 78.0p in Eastern England.
• Wed 31 Aug: London peaked at 78.0p at 06:30 (Agile's 78p cap), average 72.0p, lowest 56.1p at 23:30; highest anywhere 78.0p in Eastern England.
• Thu 1 Sep: London peaked at 78.0p at 06:00 (Agile's 78p cap), average 72.2p, lowest 55.7p at 00:30; highest anywhere 78.0p in Eastern England.

Likely causes

• From 29 Aug 2022 new Agile customers were on a version capped at 78p (AGILE-22-08-31), and on Mon 29 and Tue 30 Aug every half-hour was at that cap. (confirmed by data; see src/lib/products.mjs)
• Electric Insights: "August was by far the most expensive month ever for generating electricity", with the average wholesale price "over £350/MWh, smashing the previous record of £230/MWh set back in March", and gas peaking at £194/MWh in August. Sources: Electric Insights, Power system records (Q3 2022), Electric Insights, Power prices ease going into winter (Q3 2022). (confirmed by source)
• Mon 29 Aug 2022 was the summer bank holiday. Source: GOV.UK bank holidays. (confirmed by source)
• Mon 29 Aug, 00:00 (London's peak): wind 3GW (12% of supply), solar 0GW, gas 14.8GW (62%), imports 0.4GW, total supply 24GW. Over the day wind averaged 4GW; the 2022 average was 8.8GW (27%). Source: NESO historic generation mix. (figures confirmed by source; link to prices is inference)
• Tue 30 Aug, 00:00 (London's peak): wind 5.6GW (20% of supply), solar 0GW, gas 14.9GW (54%), imports 0.2GW, total supply 27.5GW. Over the day wind averaged 5.5GW; the 2022 average was 8.8GW (27%). Source: NESO historic generation mix. (figures confirmed by source; link to prices is inference)
• Wed 31 Aug, 06:30 (London's peak): wind 6.3GW (20% of supply), solar 0.2GW, gas 16.7GW (54%), imports 0.4GW, total supply 31.1GW. Over the day wind averaged 7GW; the 2022 average was 8.8GW (27%). Source: NESO historic generation mix. (figures confirmed by source; link to prices is inference)
• Thu 1 Sep, 06:00 (London's peak): wind 6GW (21% of supply), solar 0GW, gas 14.9GW (51%), imports 0.4GW, total supply 29GW. Over the day wind averaged 6.3GW; the 2022 average was 8.8GW (27%). 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 Mon 29 Aug (3GW, against 8.8GW for the year), so gas made up the gap. (inference from NESO data)
• Mon 29 Aug was a bank holiday (Summer bank holiday), when demand is usually lower, so high prices then are less expected. (inference)
• Elexon market index: Mon 29 Aug averaged £441.16/MWh with a high of £591.77 at 19:00; Tue 30 Aug averaged £365.17/MWh with a high of £476.99 at 17:30; Wed 31 Aug averaged £305.24/MWh with a high of £452.60 at 17:30; Thu 1 Sep averaged £371.54/MWh with a high of £527.03 at 18:30. Source: Elexon market index, Mon 29 Aug. (confirmed by source; a short-term index, not the day-ahead auction Agile follows)

Wider context that week

• Electric Insights: Russia's invasion of Ukraine on 24 Feb 2022 "had dire consequences for energy geopolitics and security". Source: Electric Insights, The cost of energy crisis (Q2 2022). (confirmed by source)

Confidence

High. The record monthly wholesale price, and every half-hour at the cap on two of the days.

Gaps

• Elexon's system warnings feed has no entries before mid-2023, so warnings for these days couldn't be checked there.