Methods and apparatus for electric power grid frequency stabilization

A method and apparatus for operating a combined-cycle power system (100) is provided. The system is coupled to an electric power grid (164). The system includes at least one electric power generator, at least one steam turbine (138) coupled to the generator (142), at least one combustion turbine (112) coupled to the generator (116), and at least one steam source (124) that is in flow communication with the steam turbine (138). The method includes operating the system at a first power output level with the steam turbine and the combustion turbine being synchronized to an operating frequency of the grid (164), so that the steam turbine (138), the combustion turbine (112), and the grid (164) are operating at a frequency substantially similar to a standardized grid frequency value. The method also includes sensing a grid frequency deviation away from the standardized grid frequency value. The method further includes accelerating or decelerating the turbines (138,112) and facilitating a predetermined rate of grid