I know that this is a question more for the cold states.
But with us being pounded with energy saving ideas all the time
we sometimes get caught up in the hype.
I feel the biggest mis-information is the wood fireplace.
Unless set up right (with a cold outside air intake) they really are not efficient.
Once you get to about 0 degrees or so, there is not benefit and after that it actually can cost you money.
Without the outside air coming in, into the furnace area, the fireplace has to use house air which
goes up the chimney as the wood burns the oxygen. Thus it creates a vacuum and brings in cold air through any air leak in the home or every time the door is opened cold air rushes in.
So, before you have alternative heating sources put in, do some good research!
Cutting your own firewood like I do is great excersise!