A combined cycle power plant that includes a first gas turbine engine including a first turbine section, a second gas turbine engine including a second turbine section having an aft outlet configured to discharge an exhaust gas stream, an emissions reduction system configured to receive the exhaust gas stream discharged from the second gas turbine engine, and configured to remove oxides of nitrogen from the exhaust gas stream, and an interstage extraction system communicatively coupled with the first turbine section. The interstage extraction system is configured to selectively extract turbine extraction air from the first turbine section for providing heat to the emissions reduction system.