Berlin

GERMANY has spent US$200 billion over the past two decades to promote cleaner sources of electricity. That enormous investment is now having an unexpected impact - consumers are now actually paid to use power on occasion, as was the case over the weekend.

Power prices plunged below zero for much of Sunday and the early hours of Christmas Day on the EPEX Spot, a large European power trading exchange, the result of low demand, unseasonably warm weather and strong breezes that provided an abundance of wind power on the grid.