PURPOSE: To reduce a quantity of steam released in the atmosphere from a steam power generating equipment having an exhaust heat boiler of a cogeneration power generating system and a garbage burning heat recovering boiler.
CONSTITUTION: When there is a surplus in total electric power generated from a cogeneration power generating system G and a steam power generating equipment, the fact that steam is released from a steam release valve 9 is detected by a steam pressure regualtor 6 to control the steam release valve 9 arranged in a steam header 5 to supply the steam from an exhaust heat boiler to recover heat energy of exhaust gas of the cogeneration power generating system G and a garbage buring heat recovering boiler 2 to a steam turbine T. When a fuel supply quantity is reduced by controlling a fuel supply device Cf to supply fuel to a gas turbine Tg according to this detected signal, since a quantity of the steam generated from the exhaust heat boiler 1 is decreased, necessary electric power can be supplied, and release of the steam from the steam release valve 9 can be also prevented.
