The invention concerns a method for energy conversion of solid fuels in particular containing carbon comprising a first step which consists in reacting said fuels in a first energy conversion reactor (2, 20). The invention is characterized in that it comprises a second step which consists in injecting oxygen brought to the output of said reactor (2, 20), the reaction of the first step being carried out in at least a circulating fluidized bed (30, 31, 40) and in that the metal oxides circulate between two interconnected circulating fluidized beds (30, 31, 40) converting the fuel and oxidizing the oxides.