' I am curious to know how potent human fuel can be. How many miles per gallon do we get as our own engines of transportation? '
He finds, after accounting for the energy intensity of American agriculture, which uses ten units of energy to get one unit of food energy, walking consumes 18-34 MPG of oil equivalent, and biking comes in at 70-130 MPG.
Maybe if we switched to a more vegetarian diet, we could improve on this."
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