Abstract:
Environmental concerns and enactments of Montreal and Kyoto Protocol for sustainable growth is a welcome impetus for researchers towards a quest for ecologically safe and natural refrigerants and cost effective designs of refrigeration systems. Carbon dioxide (CO2) is one such natural refrigerants that, although was abandoned once due techno-economic reason, has been receiving tremendous attention and is viewed as a strong candidate for long term alternative of synthetic refrigerants. The commercial success of CO2 as a refrigerant and its universal acceptance, however demands cost effective and widely accepted technology operable under various environmental conditions. In this chapter, the use of CO2 as refrigerant in trans-critical vapor compression system is discussed in detail along with its unique challenges associated with operating in tropical region. Further the opportunities for using these systems in tropical region with specific systematic modification are explored. Discussions on component design and system level performance analysis are also included in the chapter.