[IIAOPSW]

Well actually, "reversible driving" is perfectly apt in the sense of acceleration being a reversible process. It means that in theory the net energy needed to drive anywhere is zero because all the energy spent on acceleration is gained back on braking. Yes I know in practice there's always friction loss, but the point is there isn't a theoretical minimum amount of friction that has to be there. In principle a car with reversible driving can get anywhere with asymptotically close to zero energy spent.

Put another way, there is no way around the fact that a "non-reversible car" has to have friction loss because the brakes work on friction. But there is no theoretical limit to how far you can reduce friction in reversible driving.

[nine_k]

Cars specifically dissipate energy on deformation of the tires; this loss is irreversible at any speed, even if all the bearings have effectively zero losses (e.g. using magnetic levitation).

A train spends much less on that because the rails and the wheels are very firm. A maglev train likely recuperates nearly 100% of its kinetic energy during deceleration, less the aerodynamic losses; it's like a superconducting reversible circuit.

[immibis]

Actually, a non-reversible car also has no lower energy limit, as long as you drive on a flat surface (same for a reversible one) and can get to the answer arbitrarily slowly.

An ideal reversible computer also works arbitrarily slowly. To make it go faster, you need to put energy in. You can make it go arbitrarily slowly with arbitrarily little energy, just like a non-reversible car.

[EncomLab]

This is glorious.