Reduction of energy consumption by applying a new generation of CO2 compressors.

The development of transcritical CO2 systems in commercial refrigeration can be considered to be in a transition phase from cutting edge to state-of-the-art technology. However, the stress field of new developments is strong and characterized by challenging demands from the market: Further improvement of the annual energy efficiency, reduced system complexity and a decreased cost of ownership. One key to success in commercial refrigeration is the application of a new generation of energy efficient CO2 compressors in a so-called baseline system. The features of this highly efficient compressor range, which is called ECOLINE+, is explained in this paper. The European standard EN13215 is considered as the standard method for the evaluation of the annual energy efficiencies. A more complex and time consuming method to calculate the annual energy efficiency is to consider the prevailing climate, more specific load profiles, the system configuration, operating times and resulting operating conditions of the compressors applied. This work provides an analytical study of different methods to calculate the annual energy efficiency for the new compressor generation compared to the standard compressor range and discusses the results of the comparison.