To improve a ratio output as well as heat efficiency of a gas turbine effectively utilizing compressed air by driving a steam turbine and the like by superheated steam obtained by carrying out heat exchange so as to set a combustion gas temperature to a turbine heat resistance limit temperature or less.

Compressed air 15 is supplied to a device which serves as both a combustor and a heat exchanger, fuel is burnt together with stoichiometric air-fuel ratio fuel, and all superheated steam 5 generated by carrying out heat exchange without exceeding a heat resistance limit temperature of a turbine in a temperature of combustion gas 10, is individually used through respective steam regulating valve 7, and it is used for various kinds of steam turbine including all moving blades for necessitating superheated steam 5. All combustion gas is supplied to the most upstream part of various kinds of gas turbines so as to generate rotating force. An electric power generator and/or an electric motor are/is arranged as various kinds of gas turbine and various kinds of steam turbine having output shafts 12 respectively, a steam gas turbine integrated engine is arranged as a large power generation facility and/or a start device so as to utilize rotational force.