PURPOSE: To reduce the amount of fossil fuel required to a great extent, and thereby enhance parability by increasing steam temperature at the outlet of a fossil fuel burning independent reheater up to the lowest temperature level required to keep the wetness of exhaust of a reheater turbine at an allowable value.

CONSTITUTION: Steam generated by a refuse incinerator 1 is led to a high pressure turbine 31 so as to allow the high pressure turbine 31 to be driven. Its exhaust is drained off by a wetness separator 33, it is overheated again at a fossil fuel burning independent reheater 34 so as to be led to a reheating turbine 35, so that the reheating turbine 35 is thereby driven. Steam temperature at the outlet of the fossil fuel burning independent reheater 34 is increased up to the lowest temperature level required to keep the exhaust wetness of the reheating turbine 35 at an allowable value, so that the reheating turbine 35 is thereby driven. In this way, the amount of fossil fuel consumed can be reduced to a great extent, and parability can thereby be enhanced.