High ambient energy efficient CO₂ supermarket showcases

CO₂ is thought to provide lower system efficiency for commercial refrigeration systems when compared with R404A.The reason for this is that the cooling capacity of the gas cooler is often under estimated, with the same outlet refrigerant temperature is assumed for both the gas cooler and condenser. Sanyo’s field test results on the other hand, show that the CO₂ direct expansion refrigeration system consumes less electricity than an equivalent R404A system. This is because we calculated the gas cooler capacity based on the measured gas cooler outlet temperature, after which we calculated the cycle efficiency. As a result CO₂ split cycle efficiency is as same as R404A cycle when in refrigerator mode, and actually higher when in the freezer mode.