Experimental evaluation of the desuperheater influence in a CO2 booster refrigeration facility

Commercial refrigeration has undergone significant changes in recent years. In the European market, this is mainly due to the F-Gas Regulation (EU 517/2014). F-Gas affects in great measure to commercial centralized refrigeration systems for supermarkets with cooling load higher than 40 kW, where the use of refrigerants with GWP higher than 150 will be banned in 2022. As a long-term solution, CO2 has been adopted as unique refrigerant in almost all Europe overcoming the main technology hurdles. The use of booster systems in supermarkets allow covering simultaneously the medium and the low temperature services with different cycle configurations depending on the environmental conditions. The use of the desuperheater between both compression stages is a simple method to reduce the temperature at the suction port of the medium-temperature compressors improving its efficiency and therefore reducing its power consumption. The benefits of using this arrangement in terms of power consumption, discharge temperature, optimum pressure and COP, are experimentally evaluated and discussed in this work with increments in COP up to 7.05%.