One half-hour at zero
Research notes
Figures are for London unless they say otherwise.
What happened
- London touched -0.0p for a single half-hour at 08:00. Avg 13.2p, max 31.5p at 18:00. All 14 regions at or just below zero for that slot. A marginal event; the day's average was close to normal for the month.
Likely causes
- A Sunday morning with wind at about 10GW from 06:00 to 08:00 and gas down to about 2.7 to 2.9GW. Wind then faded through the day (7.3GW by midday), which fits the price recovering. Day average wind 7.7GW, peak 10.9GW. (confirmed by source) Elexon FUELHH 8 Jun
- NESO says it needed trades "for Downward Regulation" that day, which is what the operator does when there is too much generation for the demand. Balancing cost £9.11m, lower than the other event days. (confirmed by source) NESO daily balancing costs, Jun 2025
- Early Sunday morning is the lowest-demand part of the week, so 10GW of wind was enough to bring the price to zero briefly before solar had even ramped up. (inference)
Wider context that week
- Israel began strikes on Iran on 13 Jun, five days later, which pushed gas prices up for the following fortnight (see the 22 to 23 Jun section). Nothing of that kind was in play on 8 Jun.
Confidence
Medium. The data fits, but this was a one-slot event and nothing was written about it.
Gaps
- No news coverage or Met Office article found for this date.