Energy was last better‑than‑free: yesterday Next

Research notes

Figures are for London unless they say otherwise.

What happened

• Mon 2 Nov: London was below zero for 2 hours (longest spell 1 hour from 02:00), min −1.4p at 02:30; average 8.5p, peak 29.0p at 17:30; all 14 regions at 0p or below; lowest −1.7p in Northern Scotland.

Likely causes

• Mon 2 Nov, 02:30 (London's lowest half-hour): wind 11.7GW (49% of supply), solar 0GW, gas 4.2GW (18%), imports 0.5GW, total supply 24GW. Over the day wind averaged 12.7GW; the 2020 average was 7.8GW (25%). Source: NESO historic generation mix. (figures confirmed by source; link to prices is inference)
• The low came overnight on Mon 2 Nov, when demand is at its lowest (total supply as low as 24GW, against a 2020 average of 31.4GW). (inference)

Wider context that week

• Storm Aiden affected the UK on 31 Oct 2020. Source: Met Office, UK storm season 2020/21.
• England's second lockdown ran from 5 Nov to 2 Dec 2020. Source: GOV.UK, timeline of COVID-19 restrictions in 2020 (PDF). (confirmed by source)

Confidence

Low. Neither the grid figures nor any report found clearly explain this date.

Gaps

• No news report or official write-up found that ties this date to a cause; the causes above are from the data.
• Elexon's system warnings feed has no entries before mid-2023, so warnings for these days couldn't be checked there.