This paper presents the simulation modelling of thermodynamic model of 120MW coal fired power plant of that use as a thermal power generation to calculate the electrical output of a coal-fired power plant. Initially, a detailed model of a coal-fired power plant is designed to calculate energy and efficiency of the plant. This model predicts useful heat input and thermal losses that occur in the power plant. Thermodynamic models are working on the first law of thermodynamics using balance equations for each component. The power plant making some assumption performance is evaluated in design conditions. Every component is modelled as a single control volume at steady-state conditions. The pressure drops on the lines are not considered and gland steam is neglected. Trivial changes in fluid state between the outlet of one component and the inlet of the next are assumed and also the potential energy and the kinetic energy are neglected.