Abstract: The invention relates to a fuel combustion device (1) for the combustion of fuels in an exothermic chemical reaction, comprising a device (2) for supplying the fuels, a combustion chamber for combustion of the supplied fuels in a flame (10) and at least two electrodes (5, 9) through which an electrical field (E) is applied to the flame (10) with the purpose of producing a reaction plasma in said flame (10), wherein the reaction plasma produced has a high degree of ionization.