I take it back, though I searched for a bit and couldn't find useful data. What I
did find, however, is that it's actually less energy-intensive to cool air (because basically you're moving hot air outside) then to heat air (because you have to, uh, heat air).
Anyway, back to the original question. While I expect heating costs to rise, the U.S. will probably be more insulated (sorry for the pun) than Europe because a) it produces almost all of the
natural gas it consumes and b) oil imports are mostly from Canada & OPEC.