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Possibilities and Tradeoffs for Low-GWP Refrigerants



Mark O. McLinden


presentation at ASHRAE Winter Conference: We explore the possibilities for refrigerants having low global warming potential (GWP) through two distinct, but complementary, approaches. In an “exploration of thermodynamic space” we define the limits of what is allowed by thermodynamics, without being constrained by the set of presently known fluids. In the second approach, we screen 56 000 small molecules considering GWP, flammability, stability, toxicity, and critical temperature. We also calculate the COP in several different refrigeration cycles and apply efficiency as an additional screening criteria. The end result is not thousands of low-GWP candidates, but a handful. And even this limited number presents tradeoffs.
ASHRAE (Americal Society of Heating, Refrigerating and Air-Conditioning Engineers)


refrigerants, global warming potential, vapor compression cycle, efficiency


McLinden, M. (2014), Possibilities and Tradeoffs for Low-GWP Refrigerants, ASHRAE (Americal Society of Heating, Refrigerating and Air-Conditioning Engineers), [online], (Accessed July 23, 2024)


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Created January 19, 2014, Updated February 19, 2017