If it's cloudy AND your solar panels are covered with snow, how much energy is being generated?

Vail's energy efficiency sometimes hard to see | VailDaily.com

VAIL, Colorado — It’s a cloudy day, and Vail has gotten its first snowfall in weeks — it’s good for the skiing, but bad for the array of newly installed solar panels at the top of Eagle’s Nest.

Luke Cartin, Vail Mountain’s environmental manager, inspects the machines monitoring the panels and squints as he presses a few buttons. The panels, obscured from view by a layer of snow, aren’t producing much energy at the moment, he said.