Here are some numbers I worked up after a conversation with an idiot.
We use fewer resources than we did when we lived in a stick house even though our motor home gas mileage is 7 MPG. The Honda does good- about 26 MPG average and we put less than 4000 miles per year on it.
Our numbers:
12 gallons of water per day versus 160 to 200 gallons per day for two people - average use. (
http://ga.water.usgs.gov/edu/qahome.html#HDR3)
We use about 1500 gallons of gasoline per year.
Our sewage outflow (13 gallons per day) is a little more than our water useage versus 160 to 200 gallons per day for the average two couple household.
250 KWH of electricity per month versus 500 to 1000 KWH average for two people.
About 200 gallons of propane per year - would be less but we spend a couple of months in CO in the fall with family and use the furnace some there.
I used close to 1500 gallons of fuel oil per year to heat my 3600 square foot house in NH and at least 1500 KWHs of electricity per month. We now put about 4000 miles per year on the car versus 14,000 when we had the house.
The fuel and propane we use is offset by the fuel oil we used in the house. Water and electricity are quite a bit less, so it would seem to me that we are using considerably fewer resources in the motor home than we did in the house.