IN-24-C033 - A Practical Guide to Refrigerant Global Warming Potentials and Their Impacts

The global warming potentials (GWP) of refrigerants are published in multiple forms from various authoritative regulatory bodies led by the United Nation Intergovernmental Panel on Climate Change (IPCC). Unfortunately, GWP values of pure refrigerants have been published over a range of time periods with little understanding into why they have changed nor are they all published together and updated accordingly. New pure refrigerants are being developed constantly and their GWP values are not determined using previous historical methods which leads to further confusion. In addition, the user is left to understand how to calculate the GWP of the 100 plus R-400 (zeotropic) and R-500 (azeotropic) series blends using pure refrigerant data. Further contributing uncertainty is that GWP values are time horizon dependent based on their atmospheric life which leads to confusion of their impact on the environment. This paper will provide a summary of the various historically published GWP values for all pure refrigerants and their blends currently summarized in ASHRAE Standard 34. In addition, a general understanding of how GWPs of refrigerants are determined and their impacts on the environment will be provided in the paper.