R600A refrigerant has a higher refrigerating coefficient than R-12; the use of R-600a isobutane reduces energy consumption; ozone depletion potential ODR=0; global warming potential of R600A refrigerant - GWP=0,001. R-600a refrigerant is a very promising freon for household refrigerators to replace R-12 refrigerant Compared to R12 and R134a refrigerants, isobutane has significant environmental advantages. This natural gas does not destroy ozone layer (ODP = 0) and does not contribute to greenhouse effect (GWP = 0,001). The mass of refrigerant circulating in the refrigeration unit when using isobutane is significantly reduced (by about 30%), for example, in a 130-liter refrigerator there are only 20 g of Isobutane, with 12 g dissolved in the refrigeration oil. Of course, small changes would be required in the refrigerator designs. But the compressors work on mineral oils using typical electrical insulation, sealing materials and pipes of the same diameter as when the compressor works, for example, on R-12! Besides, refrigeration units with freon R-600a are characterized by lower noise level due to low pressure in the working circuit.
The specific mass of isobutane is 2 times higher than the specific mass of air, so in case of leakage, gaseous refrigerant R-600A flows on the ground. Isobutane dissolves well in mineral oil and has a higher refrigeration coefficient than R-12, which reduces energy consumption. Despite the fact that isobutane is flammable (Refrigerant Class 3 - It/DIN 8975), easily flammable and explosive, BUT only when
combination with air at volume fraction of refrigerant 1,3 - 8,5% (lower limit of explosion hazard - 31 g of R-600a per 1 m3 of air (ignition temperature - 460оС), it is allowed for use in household refrigerators. The European international standard Amendment 1 to IEC 60335-2-24, Ed.4, authorizing the use of flammable refrigerants in domestic refrigerators, stipulates requirements to the design and tests ensuring the safety of their operation. At present Italian and German companies widely apply R-600a in household refrigerating equipment. In particular, companies Necci compressori and Zanussi of the international concern Electrolux compressors, AEG, Liebherr, Foton, Bosch and others produce compressors operating on Isobutane. More than 15 million household refrigerators have been produced, the dynamics of expansion of this market is more than 10% per year. De'Longhi (Italy) and AEG (Germany) produce portable air-conditioners powered by Isobutane and plan to use them in commercial and industrial air-conditioning systems, including automobile air-conditioners. The main obstacle to the use of hydrocarbons in automobiles is the following.