SUNDAY June 16th this year was a Goldilocks sort of day across Germany, not too hot but not too cool, with bright sunshine and a reasonable offshore breeze. Just right for Germany’s solar panels and wind turbines to produce, at their peak, a record 60% of Germany’s electricity on a slow weekend. But France and Belgium also had lots of nuclear power that could not easily be cranked down. So for several hours, generating companies had to pay customers to take their surplus power.

Negative wholesale prices have become more common as European countries turn to renewables—particularly Germany, with its forced march away from nuclear power, known as the Energiewende. If at times Germany has too much of a good thing, at others it must suck power from nuclear plants across the border in France. And German ministers still worry about the risk of blackouts when the weather is cold, the sun does not shine and the wind does not blow.

Read full article on The Economist