Three variants of an oxy-type power plant were analyzed in this paper. Oxy-type plant is composed of: a boiler island (hard-coal fired pulverized-fuel boiler, electrostatic precipitator and flue gas drying installation, steam turbine unit, air separation unit with ion transport membrane and carbon dioxide capture and compression unit. Supercritical steam parameters (live steam - 650 °C/30 MPa; reheated steam - 670 °C/6.5 MPa) were used in the first variant (W1) of oxy-type power plant. In the second variant (W2) the ultracritical steam parameters (live steam - 700 °C/35 MPa; reheated steam - 720 °C/ 7.5 MPa) were used. Additionally, in this variant, the fifth low pressure regenerative water heater was added. In the last variant (W3) of oxy-type power plant, compared to the W2 variant, the second reheated steam super heater was added with steam parameters of 720 °C/1.4 MPa. It was assumed that the gross power of all these variants is 600 MW. The methodology and the results of thermodynamic analysis is presented in this paper. In addition, a method of using waste heat to partially or completely replace regenerative water heaters is presented. For this method such quantities as an increase of electrical power and increase of net efficiency of power plant were determined. The results were compared with the analogous quantities designated for a reference power plant (with the corresponding variants of the steam turbine unit).
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