Experience with industrial refrigerating systems for southern climate.

For the northern climate, nobody doubts the advantages of CO2 as a refrigerant, especially in retail applications and food processing plants. For the southern climate however, there are still some doubts in terms of efficiency. There are more and more CO2-installations in operation, equipped with efficiency increasing technology such as parallel compression or ejectors. The increasing number of CO2-installations and growing experience allows proving the predictions in terms of efficiency that optimised CO2- installations can outclass state of the art refrigerating systems, even in southern climate. In summer 2017, two transcritical CO2 racks with multi-ejector and parallel compression have been commissioned near to Valencia, Spain. The two racks are installed in a fish processing plant and replace a previous installation with R507A. The CO2-system is designed to maintain ultra-low temperature at -40°C, low temperature at -20°C and medium temperature at +2°C. The total cooling capacity of the systems is 764 kW. This paper highlights the main issues, why CO2 has been the preferred refrigerant by the end user compared to traditional ammonia systems.