Critical Pressure: 7.377 MPa, Critical Temperature
Ideal Gas Constant of Carbon Dioxide: R = 0.1889 kJ/kg.K
Source of data: NIST Chemistry WebBook - accessed March 2007
Note: The current refrigerant R134a has a Global Warming Potential (GWP) of 1300 with respect to CO2. There is currently serious consideration of replacing it with R744 (Carbon Dioxide) in refrigeration and heat pump applications, as well as automotive air conditionong systems..
A typical home heat pump system is shown below, followed by the P-h plot. Notice how the transcritical cycle conveniently allows hot water heating together with space heating and air conditioning.
Engineering Thermodynamics by Israel Urieli is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License