From physics professor Tom Murphy on his blog "Do the Math" there is a post about calculating the energy efficiency of human powered transport, including cycling: "... depending on the mode of biking and how you want to do your accounting, we got about 290 MPG in town, 160 MPG on the open road. Converting to the more universal and useful measure of energy per unit distance, these numbers map to 5 kWh/100-mi, and 2.8 kWh/100-mi. For comparison, electric cars turn in performances around 30 kWh/100-mi, and a 40 MPG car uses 90 kWh/100-mi (but beware a direct comparison between these last two: if the electricity is derived from fossil fuels, the fossil fuel investment becomes similar for the two: we’ll get to this for food in a bit)."