RT Journal Article SR Electronic A1 Sikora, Kamil T1 Study of the Consequences of Changes in the Composition of Natural Gas JF Acta Mechanica Slovaca YR 2022 VO 26 IS 2 SP 48 OP 51 DO 10.21496/ams.2023.001 UL https://www.actamechanica.sk/artkey/ams-202202-0008.php AB The following study deals with the consequences of the change of some components of natural gas due to a change of supplier. This is mainly an increase in the amount of ethane, at the expense of methane. This is associated not only with a change in higher calorific value and lower calorific value, but also with a changed ratio of flue gas components, is the amount of CO<sub>2 </sub>generated. The heat released during combustion can be expressed either by higher calorific value (HCV) or lower calorific value (LCV). HCV is higher than the LCV by the condensation heat of the water vapor contained in the flue gas.