Energy efficiency evaluation of integrated CO 2 trans-critical system in supermarkets: A field measurements and modelling analysis

This paper investigates energy efficiency of an integrated CO 2 trans-critical booster system installed in a supermarket in Sweden. The supermarket has applied several features to improve energy efficiency including space and tap water heating, air conditioning (AC), and parallel compression. Using field measurements data, the system performance is evaluated in a warm and a cold month. Furthermore, this integrated energy system concept is modelled and compared with stand-alone HFC-based energy systems. The results show that the system provides the entire AC demands and recovers a great share of the available heat, both with high COP values. The comparative analysis shows that integrated CO 2 system uses about 11% less electricity than stand-alone HFC solutions for refrigeration (i.e. indirect HFC), heating and AC in North of Europe. Energy efficiency analysis of the integrated CO 2 system proves that this system is an environmentally friendly all-in-one energy efficient solution suitable for cold climate supermarkets.