A combustor/coil assembly for direct electromagnetic induction from a detonation wave comprises an annular combustor, a magnetic field source and a port. The annular combustor comprises an inner liner and a coaxial outer liner. The outer liner is electrically insulated from the inner liner. The magnetic field source generates a substantially axial magnetic field inside the annular combustor. The port introduces reactants into the annular combustor to form the detonation wave. The detonation wave induces a voltage between the inner liner and the outer liner by forming a current loop between the inner liner and the outer liner.