Behzad NJ

Hello guys Yesterday I was studying thermodynamics , now I've got this problem ! In the power plants we want to convert Q to W , in most cases at the end of cycle we uses some tools to reduce the amount of this Q , but why ? Why don't we use low amount of Q ? so that we don't need to reduce it at the end . And could you please let me know what books do you study in thermodynamics ? I'm studying Thermodynamics by Cengel . Best Regards