Another thought:

Behavior trumps virtue signaling. If you choose to be efficient, you will, even in less than ideal circumstances. 

This calls to mind the video from the old Top Gear where Clarkson drove the piss out of a Prius and then dawdle around the track at the same average speed in a BMW. Beating on the Prius yielded a worse average fuel consumption than just driving well under the performance envelope of the BMW. 

I find myself doing these calculation often in my own living situation, especially since I want to be able to sustain living off-grid for a while.