Abstract: The present application provides a combined cycle system. The combined cycle system may include a number of gas turbine engines, a number of heat recovery steam generators with a selective catalyst reduction and/or oxidation catalyst system, and a catalyst heating system. The catalyst heating system directs an extraction from a first gas turbine engine of the number of gas turbine engines to the selective catalyst reduction and/or oxidation catalyst system of a second heat recovery steam generator of the number of heat recovery steam generators.

Abstract: The present application provides a combined cycle system. The combined cycle system may include a number of gas turbine engines, a number of heat recovery steam generators with a selective catalyst reduction and/or oxidation catalyst system, and a catalyst heating system. The catalyst heating system directs an extraction from a first gas turbine engine of the number of gas turbine engines to the selective catalyst reduction and/or oxidation catalyst system of a second heat recovery steam generator of the number of heat recovery steam generators.

Abstract: Embodiments of systems and methods described in this disclosure are directed to operating a combined cycle power plant. In certain embodiments, systems and methods can be provided for a combined cycle power plant incorporating a control system that uses a holistic approach to continuously and automatically adjust a heat rate of the combined cycle power plant and achieve a desired efficiency. In accordance with one embodiment of the disclosure, the control system can be used to dynamically control various operations of the combined cycle power plant, including addressing of certain conflicting requirements such as avoiding generation of superheated steam in an attemperator while concurrently maintaining exhaust emissions within allowable regulatory limits and maintaining exhaust gas temperatures within allowable material capability limits.