The invention relates to an energy converting device comprising a gas generator (6) for the production of a hydrogen-oxygen mixture and/or brown gas, comprising a reaction chamber (19) wherein electrodes (29) are arranged. Said reaction chamber (19) is rotationally-symmetrical with respect to an axis (18). Internal defining surfaces (20) of the reaction chamber (19) are formed in the region of thejacket (21) of the reaction chamber (19) at least in certain areas by internal electrode surfaces (30, 31) of the electrodes (29) of the gas generator (6).