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Low-GWP Refrigerants; Options and Issues



Piotr A. Domanski, Riccardo Brignoli, J S. Brown, Andrei F. Kazakov, Mark O. McLinden


This research explored the possibilities for refrigerants having low global warming potential (GWP) with a particular focus on high-pressure applications. The search for suitable refrigerants relied on screening of a comprehensive database using filters of environmental acceptance, chemical stability in the system, low toxicity, coefficient of performance (COP), volumetric capacity (Qvol), and flammability. Among different screening steps, the performance potential (COP and Qvol) of the candidate fluids was assessed using a simulation model that included both thermodynamic and transport properties, and heat exchangers with optimized refrigerant circuitry. The study showed that the low-GWP refrigerant options are very limited, particularly for fluids with volumetric capacities similar to those of R-410A and R-404A. The identified fluids with good COP and low toxicity are at least mildly flammable. Accepting the thermodynamic argument that viable refrigerants are restricted to small molecules, it is out contention that the screened database contained all suitable candidates and our screening process yielded a list of the 'best' low-GWP fluids. Refrigerant blends allow for tradeoffs between COP, volumetric capacity, flammability, and GWP. The probability of finding "ideal", better-performing low-GWP fluids is minimal.
Proceedings Title
Int. Conference on Cryogenics and Refrigeration 2018, April. 12-14, 2018, Shanghai.
Conference Dates
April 12-14, 2018
Conference Location
Shanghai, CN


Air conditioning, coefficient of performance, refrigeration, thermophysical properties, working fluids


Domanski, P. , Brignoli, R. , Brown, J. , Kazakov, A. and McLinden, M. (2018), Low-GWP Refrigerants; Options and Issues, Int. Conference on Cryogenics and Refrigeration 2018, April. 12-14, 2018, Shanghai., Shanghai, CN, [online], (Accessed June 12, 2024)


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Created April 11, 2018, Updated April 11, 2022