Scarcity at sunset

The Hour the Sun Let Go

At 20:00 CEST on 23 June 2026 (the hottest day France had measured since national records began in 1947) the German bidding zone's day-ahead hour delivered at €548.75 per megawatt-hour. Seven hours earlier the same auction had sold the 13:00 hour, same zone, same day, for €53.53. Ten times the price, one rotation of the same summer afternoon, and nothing broken anywhere: no plant tripped between lunch and dinner, no cable failed, no market malfunctioned. The most expensive electricity of the European summer was sold at sunset, on days when midday power was nearly free.

It got worse the next evening, and it got worse in a very specific way. On 24 June the Dutch zone's 21:00 hour cleared at €799.36; the German 20:00 hour at €683.99; and Belgium (a zone our own database does not carry, so the number is Montel's, not ours) paid €1,038.25 for the fifteen minutes between 20:45 and 21:00, the highest price in the short life of its quarter-hour day-ahead product. This editorial is about why a heatwave now does this: why the third summer of the solar age put its record prices at dusk, what the water then did to France's reactors and Germany's coal barges, and why a stress test that began with a Météo-France bulletin on 23 June was still generating regulatory filings in London on 17 July. The numbers, unless attributed otherwise, are measured, most of them from our own database.

Because this is the part worth paying for: the June 2026 heat dome was not a repeat of the stress Europe already knows. It was the first full-dress rehearsal of a different one: the stress of a system that has solved its middays and not its evenings, run at 44 °C.