Drop-in and retrofit refrigerants as replacement possibilities of R134a in domestic/commercial refrigeration and automobile air conditioner applications

Abstract

According to the EU F-gas Regulation, the phase-out of the high global warming potential (GWP) refrigerants (with higher than 150 GWP value) had been established. The most currently existing household and commercial refrigerators and automobile air conditioners applications based on single-stage vapour compression systems operate with R134a as working fluid. The present paper aims, to review and evaluate the performance of a set of eco-friendly alternatives refrigerants to replace R134a, without change or with minor modifications in refrigeration equipment. The theoretical and experimental studies performed in this field of research were reviewed for this objective. These alternative refrigerants are some of HFCs, HFOs and HCs and their mixtures, which are expected to be an excellent candidates in many refrigeration applications. There are Many replacement possibilities had been proposed viz. drop-in replacement, retrofit refrigerant, and new systems. The results exhibited that the most suitable refrigerants as R134a drop-in substitutes are R1234yf, R152a, R450A, and R513A. The pure R1234ze and its mixtures are not suitable drop-in replacements of R134a but can be a good alternative to R134a only in new refrigeration systems. In terms of hydrocarbon refrigerants R290, R600, and R600a could replace R134a with some modifications to existing refrigeration systems to overcome the flammability issue. We should be using certain HFC and HC mixtures with the lowest TEWI index.

Performance Evaluation of Split Air Conditioner with Consideration of Pressure Drop in Evaporator and Condenser

“…The ratio of COP of the system under consideration to COP of the system operated reversibly (Carnot COP) is known as energetic efficiency, ... (7) Exergy destruction ratio (EDR) is ratio of irreversibility associated with a component to the exergy of fuel supplied. 10 ... (8) The efficiency defect (δ i ) is an indicator that gives the information about the fraction of energy (input) destroyed in a specific component so that one can find the component which performs worst in the system.…”

“…Refrigerator freezers and air conditioners were shown to be responsible for 21% and 12% of total exergy loss, respectively. HMOOD et al 8 reported that R1234yf could be a better drop in alternative to high GWP refrigerant R134a. Tarish et al 9 perform the exergy analysis using R161 operated in split air conditioner to find an alternative to R134a and R22 in different Iraq climate and find that the exergy efficiency of R161 operated system is 8.6% and COP is 7.3% higher than the R134a and R22 operated systems.…”

Teorijska analiza niskozapaljivih i ekološki prihvatljivih smjesa ukapljenog naftnog plina i tetrafluoretana kao hladila

“…Halogenated refrigerants, especially chlorofluorocarbons (CFCs) and hydrochloroflurocarbons (HCFC), are the commonly used refrigerants in vapour compression refrigeration systems over the past century, Because of their outstanding thermodynamic and thermo-physical qualities. However, they possess poor environmental qualities due to their undesirable contributions to the ozone layer destruction and climate change by reason of their high global warming potential (GWP) (Hmood et al, 2021). In 1987, Montreal Protocol regulated the use of both the partially and fully halogenated chemicals including hydro-chlorofluorocarbons (HCFCs) and CFCs in air-conditioning and refrigeration systems as a result of their high ozone depletion potential (ODP) (Bolaji, 2014).…”

Experimental study on refrigerant mixing as a drop-in substitute for R134a in a domestic refrigerator

“…The refrigerant mass charge of R290/R600a was nearly 50%, with refrigeration effect higher by 35.29 percent and 12.5 percent, compressor operation lower by 9.12 percent and 14.68 percent, COP larger by 46.92 percent and 31.91 percent, and discharge compressor temperature lower by 8K and 5K than R134a, respectively. R134a/R1234yf (10:90, by weight) was used in an experimental study by Hmood et al [12] to replace R134a in a refrigerator. The electrical energy consumption was reduced by 7.5 percent, and the pull-down time was reduced by 14 percent in the binary mixture R134a/R1234yf.…”