Developing low-GWP refrigerant blends of R32/R152a/R1270 for improved energy efficiency in HVAC systems

Abstract

This study evaluates low-GWP refrigerant blends of R32, R152a and R1270 as potential replacements for high-global warming potential (GWP) refrigerants like R410A and R32, aiming to achieve environmental sustainability, energy efficiency and retrofit feasibility in HVAC systems. Seventy blends were analysed through thermodynamic modelling, assessing environmental impact, safety considerations and thermodynamic performance, with key indicators including coefficient of performance (COP), cooling capacity and compressor discharge temperature (CDT). The results identify six optimal blends–RA1, RB5, RB9, RC2, RC6 and RC8–each with a GWP below 750 while maintaining performance comparable to R410A and R32. RA1 demonstrated the highest COP and cooling capacity but exhibited an elevated CDT, necessitating improved thermal management. RB9 provided the lowest temperature glide, enhancing system stability, while RC8 exhibited the highest mass flow rate and lowest CDT, making it suitable for retrofitting existing systems. These findings highlight the potential of next-generation refrigerants that align with global regulatory requirements while offering practical benefits for system integration.