Energy was last better‑than‑free: yesterday Next

On the Agile Octopus tariff, customers get paid to use electricity when there’s too much in the grid.

That’s cheaper than Octopus Energy paying to store it.

The price changes every half-hour.

Period

Region

Negative prices (overnight)

Sat 1 Feb · Mon 3 Feb

Figures are for London unless they say otherwise.

Sat 1 Feb: London was below zero for half an hour from 03:30, min −0.1p at 03:30; average 7.0p, peak 23.5p at 18:00; all 14 regions at 0p or below; lowest −0.1p in Merseyside and Northern Wales.
Mon 3 Feb: London reached 0p at 03:30; average 7.6p, peak 24.1p at 17:30; all 14 regions at 0p or below; lowest 0.0p in Eastern England.

Sat 1 Feb, 03:30 (London's lowest half-hour): wind 13.1GW (48% of supply), solar 0GW, gas 3.9GW (14%), imports 1.5GW, total supply 27.4GW. Over the day wind averaged 12.6GW; the 2020 average was 7.8GW (25%). Source: NESO historic generation mix. (figures confirmed by source; link to prices is inference)
Mon 3 Feb, 03:30 (London's lowest half-hour): wind 13.6GW (49% of supply), solar 0GW, gas 2.7GW (10%), imports 0.8GW, total supply 27.6GW. Over the day wind averaged 13.9GW; 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 Sat 1 Feb and Mon 3 Feb, when demand is at its lowest. (inference)
Sat 1 Feb was at the weekend, when demand is lower. (inference)
Elexon market index: Sat 1 Feb averaged £21.14/MWh with a low of −£23.15 at 11:00; Mon 3 Feb averaged £24.48/MWh with a low of −£11.00 at 04:00. Source: Elexon market index, Sat 1 Feb. (confirmed by source; a short-term index, not the day-ahead auction Agile follows)

Storm Ciara followed on 8 and 9 Feb 2020. Source: Met Office, UK storm season 2019/20.
Electric Insights says wind farms averaged a record 12.3GW through February 2020. Source: Electric Insights, Power system records (Q1 2020). (confirmed by source)

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

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.

Saturday 1 Feb 2020 · half-hourly prices

South Eastern England

−0.1p

Cheapest half-hour 3.30am – 4am

24.6p

Dearest half-hour 6pm – 6.30pm

0.5 hours

Negative prices 3.30am – 4am

0.4p avg

Cheapest 3 hours 2.30am – 5.30am

7.5p

Average price on 1 Feb 2020

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