Combined cycle power plants (CCPP) are very important to the global power generation industry. The thermodynamic behavior of these cycles is usually studied to determine the optimal configuration and optimal design conditions for any cycle arrangement. In a combined rotary power plant, many factors affect the cycle efficiency and output power. The temperature of the turbine exhaust gas greatly affects the optimal design and configuration of the heat recovery generator. In fact, when the exhaust gas temperature drops, if the number of pressure levels increases, the energy output and heat recovery will increase sharply another important parameter is the ambient temperature. When the ambient temperature increases, the density of the inlet air decreases, so the mass flow through the turbine decreases, and the output power also decreases. In addition, the energy demand for compressing the air in the compressor increases, so the net electrical energy produced by the compressor ranks first in the reduction cycles.