To obtain a combination engine of a diesel engine, a gas turbine, and a steam turbine with the best thermal efficiency, by mounting a plurality of gas generators each in which a reciprocating type supercharger is directly connected to a crankshaft of a diesel engine and guiding emission gas which has a pressure and a temperature to one exhaust turbine.

A reciprocating type supercharger 2 is directly connected to and driven by a crankshaft of a diesel engine 1, thereby completing a so-called gas generator in which all output of the engine is consumed. The effective output becomes gas of a certain pressure and temperature. A plurality of these gas generators are mounted, and gas is collected and guided to one exhaust turbine 8, whereby a large output is obtained. Further, steam generated from a cylinder and supercharger low-pressure steam jackets 11, 15 is guided to a low-pressure stage of a steam turbine 9, and steam generated from a cylinder and piston head high-pressure steam jackets 12, 13 is guided to the steam turbine through a heater 10, whereby power is recovered. A waste-heat boiler 14 uses waste heat of the exhaust turbine 8 to generate steam and recover power.