The objective of this study was to investigate the cooling performance
characteristics of an electrical air conditioning system using R744 as an alternative of
R-134a for a fuel cell electric vehicle. In order to analyze the cooling performance
characteristics of the air conditioning system using R744 for a fuel cell electric vehicle, an
electrical air conditioning system using R744 was developed and tested under various
operating conditions according to both inlet air conditions of the gas cooler and evaporator
and compressor speed. The cooling capacity and coefficient of performance (COP) for
cooling of the tested air conditioning system were up to 6.4 kW and 2.5, respectively. In
addition, the electrical air conditioning system with R744 using an inverter driven
compressor showed better performance than the conventional air conditioning system with
R-134a under the same operating conditions. The observed cooling performance of the
developed electrical air conditioning system was found to be sufficient for cooling loads
under various real driving conditions for a fuel cell electric vehicle.