This study investigated the cooling performance characteristics of the electrical air conditioning
system using R744 for a fuel cell electric vehicle. In this investigation, the inlet air conditions of both
gas cooler and evaporator and the compressor speed were varied. Experimental results showed that the
cooling capacity and cooling COP of the electrical air conditioning system using R744 were sufficient
to cover the cooling load of the fuel cell electric vehicle under hot weather conditions and the cooling
capacity and the cooling COP of the tested system increased up to 6.4 kW and 2.5, respectively. As a
result, the developed electrical air conditioning system could be very helpful for improving the driving
efficiency of the fuel cell electric vehicle because it would consume less electric energy from the high
voltage battery system and provide higher cooling COP. 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