Analysis of efficiency of 'zero-emission' oxy-type ultra-supercritical power unit based on high-temperature membranes

Oxy-combustion technology by eliminating, in the stage of preparation of oxidant, atmospheric nitrogen from combustion process is characterised by a high concentration of carbon dioxide in the exhaust gas, and thus, facilitates its sequestration. Power unit that operates in classic (air) combustion technology with a gross power output similar to the power of the investigated model is characterised by a CO₂ emission of 860 kg/MWh. The use of oxy-combustion allows to reduce the carbon dioxide emissions by more than 90%, so it is worth to present both thermodynamic and economic consequences of the introduction of this technology. Thermodynamic analysis of the model assumed investigation of the impact of changes in the oxygen recovery rate on the basic characteristics of the power unit. In the next stage of calculations the estimated capital expenditures and a break-even price of electricity under the assumption that NPV is equal to zero were determined.