Your body works overtime anytime its out of homeostasis, hot or cold. Cold generally more at rest because you are burning extra just to stay warm, but while exercising you are already stoking the furnace so the gains are less so.

I like this a little better. Huzzah photoshop.

Yeah. I think the headline is wrong.
It should say something like;
"Occupants Turn Greenest Skyscraper Into Total Energy Hog"