Negative prices
Sat 25 Jul · Sun 26 Jul
Research notes
Figures are for London unless they say otherwise.
What happened. Sat: London down to −6.6p at 12:00 (the lowest price of the whole period), below zero 8 hours from 08:00. Sun: −5.2p at 13:30, below zero 5 hours.
Likely causes
- A breezy, sunny weekend after a calm fortnight. Wind averaged 8.8 GW and 8.7 GW (it had been 3.5 to 5.5 GW on 20 to 24 Jul); solar peaked at 13.4 GW and 11.1 GW. At Saturday's low point wind was 11.5 GW, solar 12.9 GW, gas plant 1.9 GW. On Sunday gas plant never rose above 2.6 GW all day (confirmed by data) Elexon FUELHH 25 to 26 Jul, PV_Live 25 to 26 Jul
- Weekend demand (inference).
Wider context that week. Gas hit its Jul high (about 150p) on 23 Jul as Brent went back over $100 after attacks on Middle East shipping Catalyst 24 Jul. So these negative prices came with gas near its most expensive of the month, which shows up in the evening peaks (38.2p and 35.0p). On Mon 27 Jul Trump called off a strike on Iran and oil fell $8 Catalyst weekly, 27 to 31 Jul. The long Jul heatwave ended on 26 Jul.
Confidence. Medium to high, on data alone.
Gaps. Catalyst published no dailies between 24 Jul and 3 Aug, and nothing else found mentions this weekend.