Solar chimney power plants (SCPPs) attract attention with their simple structure and 24-hour power output. Following the first prototype Manzanares, the sensitivity of the system to climatic and geometric parameters is evaluated in detail. It is clear that solar radiation intensity is an important parameter in power output. However, changes in geometric dimensioning will cause different effects on system performance. Another way to increase system performance is to provide hybrid systems that provide more energy input. In this study, the waste heat of a gas power plant is evaluated with the piping system to be integrated into the base of the solar chimney power plant. By utilizing waste heat at the base of the system, more power output is aimed at with more heat input. Simulations are made with the 3D CFD model created for this purpose. In the reference case, the performance of the system, which gives a power output of 54.141 kW under 1000 W/m2 solar radiation and 293 K constant climate conditions, increases by 138% in system performance with the application of waste heat under the ground. The aim of the study is to show that SCPPs will produce electricity even when there is no sun. As long as this continuity is ensured, the aim is to obtain power output from the system. By applying 250°C waste heat during hours when there is no sun, 101.524 kW power output can be obtained from the system.