METHOD FOR OPERATING A COMBINED CYCLE POWER PLANT WITH COGENERATION AND A COMBINED CYCLE POWER PLANT FOR CARRYING OUT THE METHOD

摘要

The invention relates to a method for operating a combined cycle power plant (10) with cogeneration in which method combustion air is inducted in at least one gas turbine (11) is compressed and is fed to at least one combustion chamber (19) for combustion of a fuel and the resultant exhaust gas is expanded in at least one turbine (20) producing work and in which method the exhaust gas which emerges from the at least one turbine (20) is fed through a heat recovery steam generator (13) in order to generate steam which heat recovery steam generator (13) is part of a water steam circuit (12) with at least one steam turbine (14) a condenser (32) a feedwater tank (28) and a feedwater pump (P2) wherein heat is produced by extraction of steam from the at least one steam turbine (14). In a method such as this simple decoupling of heat and electricity production which is advantageous for operation is achieved in that the steam can be selectively extracted from the at least one steam turbine (14) as low pressure steam or intermediate pressure steam and in that the steam extraction is switched from low pressure steam to intermediate pressure steam in order to restrict the electricity production.