Abstract: A method for the simultaneous generation of electrical energy and heat for heating purposes uses a combustion gas consisting mainly of one or more hydrocarbons as well as a gas mixture containing oxygen. The method is carried out by means of at least one gas burner and at least one stack of fuel cells, with an oxygen surplus having a stoichiometric ratio greater than about 3 being provided in the battery. In the battery less than half of the combustion gas is converted for the generation of electricity while producing a first exhaust gas. The remainder of the combustion gas is burned in the burner while producing a second exhaust gas, and the first exhaust gas is used at least partially as an oxygen source for the combustion. Heat energy is won from the exhaust gases, with at least about half of the water contained in the exhaust gases being condensed out.