A new environment-friendly refrigerant

CFCs and HCFCs, widely used in refrigeration and air-conditioning equipment , have been or will be phased out according to the revisions of the Montrea l Protocol because they deplete the ozone layer. Many substitutes have been proposed, but no one has perfectly replaced the CFC and HCFC refrigerants. New generation alternatives are being investigated worldwide. According to the industrial and environmental requirements, many factors should be cons idered in the screening and evaluation of refrigerant alternatives. A new m ethod is proposed using the soft algebra method-fuzzy multiple evaluation. The weights for different factors are determined mathematically and criteri a values for all the objects are made dimensionless to quantitatively compa re the different alternatives. A new long-term drop-in mixture alternative THR02 is developed and evaluated in a series of theoretical and experimenta l evaluations. THR02 is proved to be an environment-friendly, nontoxic, inf lammable, drop-in alternative to CFC-12 and HFC-134a. The thermal performan ce of the compressors and refrigerators with THR02 as a drop-in is equal to or higher than with CFC-12 and HFC-134a. The compressor and refrigerator u sing THR02 perform reliably after long-period running.