  A quantum heat engine (QHE) based on the interaction driving of a
many-particle working medium is introduced. The cycle alternates isochoric
heating and cooling strokes with both interaction-driven processes that are
simultaneously isochoric and isentropic. When the working substance is confined
in a tight waveguide, the efficiency of the cycle becomes universal at low
temperatures and governed by the ratio of velocities of a Luttinger liquid. We
demonstrate the performance of the engine with an interacting Bose gas as a
working medium and show that the average work per particle is maximum at
criticality. We further discuss a work outcoupling mechanism based on the
dependence of the interaction strength on the external spin degrees of freedom.
