  We investigate the performance of a quantum thermal machine operating in
finite time based on shortcut-to-adiabaticity techniques. We compute efficiency
and power for a quantum harmonic Otto engine by taking the energetic cost of
the superadiabatic driving explicitly into account. We further derive generic
upper bounds on both quantities, valid for any heat engine cycle, using the
notion of quantum speed limits for driven systems. We demonstrate that these
quantum bounds are tighter than those stemming from the second law of
thermodynamics.
