Just read in this interesting post at www.theoildrum.com that Americans in 2004 consumed about 342,700,000 Btu (British thermal units, the standard measure of energy), per capita, per year. That converts to about 230,000 nutritional calories per day. Only two or three thousand of those calories are consumed in the form of food; the rest of the energy--well over 200,000 calories' worth per day--is used to heat and cool our homes, transport us from place to place, etc.
Obviously, that's a lot of energy. I wonder how much of it is used needlessly? I know I use more than I need to just for foolish reasons; for instance, making multiple grocery shopping trips per week, when a minimum of foresight would enable me to get everything in one trip. Each shopping trip uses about a gallon of gas, which contains energy equivalent to about 31,000 calories. Plus it uses other resources, like my time--forty minutes of driving alone, plus the time spent in the store. I think I need to try to be more conservative (with resources). :)
I recommend the www.oildrum.com site--very interesting, especially today's post on windmills. :)