  Shortcuts to adiabaticity let a system reach the results of a slow adiabatic
process in a shorter time. We propose to quantify the "energy cost" of the
shortcut by the energy consumption of the system enlarged by including the
control device. A mechanical model where the dynamics of the system and control
device can be explicitly described illustrates that a broad range of possible
values for the consumption are possible, including zero (above the adiabatic
energy increment) when friction is negligible and the energy given away as
negative power is stored and recovered by perfect regenerative braking.
