Die Dunkelflaute or dark lulls have drawn attention to the need for dispatchable power (typically from gas turbines or coal-fired power plants) when the weather isn’t cooperating.
The massive power outage in Spain and Portugal on Monday may be the result of the opposite challenge – a surge in solar power supply greatly exceeding demand (dark line in chart below).
Note that no extreme weather events were reported in Spain on April 28, 2025. The Portuguese grid operator mentioned “extreme temperature variations” in Spain’s interior, possibly causing grid oscillations, but no storms or heatwaves were noted. Weather was typical for April, with mild temperatures (8-19°C) and some rain.
Meanwhile, the political focus in the US (chart below), and perhaps more so in Europe, had been on “clean” rather than reliable power.
Bottom line: Over-reliance on highly variable wind and solar power challenges grid management, putting supply reliability at risk.
Bud's Offshore Energy (BOE) 