Master thesis Efficiency analysis of cement plant is based on the work of Koromačno cement factory. The thesis is divided into nine chapters. At the beginning of the thesis, the history of cement production in Croatia and in the world is described, as well as the process of cement production. The technological process of cement production at the Koromačno factory is presented in detail, from the extraction of mineral ore to the shipment of the finished product. The next part of the thesis describes the way to increase the thermodynamic efficiency of the cement industry. Three different types of processes are presented on how to generate electricity from the waste heat of the cement industry, which is released into the environment during most processes. In the further course of the thesis, two different models that can use waste heat were created using the program Ebsilon Professional. Based on the parameters obtained, a technical and economic analysis of the cost-effectiveness of these systems was carried out. The comparison of the two models is provided to the potential investor to consider which system to use. In the last part of the thesis, the models were tested for three different temperatures of the exhaust gasses and hot cooling air. The temperatures chosen are in the range that can be expected in practice in the cement industry. A graphical comparison of these temperatures for the power generated and the overall efficiency of the system is presented.