Dunkelflaute: the weeks the wind forgot Germany

The Wind Delivered 111 Megawatts

On the evening of Wednesday 6 November 2024, between five and six o'clock, electricity for delivery in Germany cost €820.11 per megawatt-hour. The price had been set the previous lunchtime, in the ordinary course of the day-ahead auction, and nobody who had looked at a weather forecast was surprised by it. Germany's wind fleet (63.6 GW onshore and 9.2 GW offshore, some 72.8 GW of nameplate capacity accumulated over a quarter of a century of energy transition) delivered, in that hour, 111 megawatts. Not gigawatts: megawatts. Roughly 0.15% of what the fleet could produce with the wind blowing, or about what eight modern offshore turbines manage on a good day. Solar contributed 40 MW; the sun had set an hour earlier. Demand was 66.4 GW, and essentially all of it, 99.8%, had to come from something other than wind and sun.

The hour barely made the German front pages, because the same evening produced a larger story: at around nine o'clock, Chancellor Olaf Scholz fired his finance minister, Christian Lindner, and the three-party coalition that had governed Germany since 2021 collapsed. The country's most expensive electricity hour in years and the end of its government arrived on the same November evening, and, as we shall see, the coincidence was not entirely without consequence, because among the legislative casualties of the collapse was the very law that had been written to deal with hours like this one.

Five weeks later the weather did it again, and this time everyone was watching. On Thursday 12 December 2024, the hour from five to six in the evening cleared at €936.28/MWh: the highest German day-ahead price in eighteen years, as Fortune noted, worse than anything seen even in the panic winter of 2022. The whole day averaged €395/MWh against a 2024 mean of about €79. Montel's analysts had forecast German wind output dropping to 2.8 GW against a seasonal norm of around 19 GW; the reality at the evening peak was 1.3 GW. And this time the price did not stay inside Germany. It travelled up the cables to southern Norway and southern Sweden, arrived in the spot bills of Norwegian households at levels not seen since 2009, and set off a political chain reaction that is still running.