Thermodynamic analysis of low-GWP blends to replace R410A for residential building air conditioning applications

The Kyoto Protocol has stipulated array of national policies to combat the climate change. To tackle the global warming, governments embraced Paris Agreement and Kigali Amendment which deal with the reduction of greenhouse gas emission. For example, the European F-gas regulation and the Japan METI now enforce refrigerants below 150 GWP for automobile industry and below 750 GWP for the residential air-conditioning applications. To invent a perfect refrigerant that meets performance requirement, environmental requirements, and safety standards is considered extremely difficult. On the other hand, some existing refrigerants exhibit excellent performance with safe operation but record high-GWP while refrigerants such as R1234yf and R744 possess almost 0 GWP. Thus, these refrigerant blends might serve as urgent solutions with minimum performance compromise. This paper evaluates the performance of binary and ternary blends using several promising refrigerants. Exploiting the excellent performance of R32 as the base refrigerant, R1123, R1234yf, R1234ze(E), and R744 are utilized in the blends. The performance indicators employed here are (i) GWP, (ii) temperature glide, (iii) volumetric capacity, and (iv) coefficient of performance. The advantages to reduce the irreversible heat loss by glide matching and energy saving potential for the blends are also discussed. Results showed that some refrigerant blends considering GWP 200 and 300 could successfully replace the widely used R410A in a residential air conditioner. [Figure not available: see fulltext.].