R744 ejector system case: Italian supermarket, Spiazzo.

According to IPCC/TEAP the annual refrigerant leaks from commercial refrigeration units related to the total charge are between 15 and 20 % in Europe and ~30 % outside Europe. Phasing out the current H(C)FC systems in the near future with efficient systems applying natural working fluids would result in a significant reduction of the environmental impact of commercial refrigeration. Special R&D effort has been given to the development of high efficient R744 commercial refrigeration systems. The utilisation of expansion work in combination with overfed evaporators has shown to be the key to outperform current H(C)FC systems even in high ambient temperature climates as in the current case of Spiazzo. A new supermarket located in the Trento province in Italy was commissioned in September 2014. The supermarket is equipped with an ejector supported R744 parallel compression unit. The refrigeration pack is also able to perform 100% of the AC load supplied with the ventilation system. Between 15 and 30% of energy saving was achieved when expansion work recovery was utilized to unload the MT compressors by high efficient vapour ejectors implemented in a Mulitjet arrangement.