[readingistuff]

Electric bicycles are actually more efficient than bicycles (which are themselves more efficient than walking). The combination of human power and electric assist uses less total energy than human power alone!

[rpozarickij]

I wonder how is it possible to use less total energy? If you need to apply an amount of energy to travel a given distance, the amount can't be that different whether the energy comes from muscles or from an electric motor (or a combination of both). These are different sources of energy, but it's still energy.

I'd imagine the movement of the legs while pedalling would affect the aerodynamics, but is there something else happening?

[rhn_mk1]

It requires looking farther back into where the energy comes from. Humans are rather inefficient at converting calories in carbohydrates into movement. Electric motors are comparatively better at turning electric potential energy stored in batteries to kinetic energy.

Keep going this way and you'll eventually reach the efficiency of converting solar power to movement, which is again directly comparable, and electrical systems win compared to biological systems.

[r00fus]

Wouldn't recharging an electric battery be more efficient than cooking the calories to fuel the human?

[hoerensagen]

I would imagine that the efficiency of a human peddling depends on the speed. So maybe it's more efficient if the motor does most of the work to get you up to speed?

[rsynnott]

I would suspect regenerative braking (assuming that this is actually true).