Abstract
This part of the study investigates the performance of HFC refrigeration systems for supermarkets and compares the performance with alternative CO2 trans-critical solutions. The investigated HFC system solutions are typical in supermarkets in Sweden. The analysis in this study is based on field measurements which were carried out in three supermarkets in Sweden. The results are compared to the findings from Part I of this study where five CO2 trans-critical systems were analyzed.Using the field measurements, low and medium temperature level cooling demands and COP’s are calculated for five-minute intervals, filtered and averaged to monthly values. The different refrigeration systems are made comparable by looking at the different COP’s versus condensing temperatures. The field measurement analysis is combined with theoretical modelling where the annual energy use of the HFC and CO2 trans-critical refrigeration systems is calculated.Comparing the field measurement and modelling results of COP’s for HFC and CO2 systems, the new CO2 systems have higher total COP than HFC systems for outdoor temperatures lower than about 24°C. The modelling is used to calculate the annual energy use of HFC and new CO2 system in an average size supermarket in Stockholm, new CO2 systems use about 20% less energy than a typical HFC system.The detailed analysis done in this study (Part I and Part II) proves that new CO2 trans-critical refrigeration systems are more energy efficient solutions for supermarkets than typical HFC systems in Sweden.
Highlights
Supermarkets are known as one of the largest emitters of high GWP refrigerants in Europe according to the Intergovernmental Panel for Climate Change special report [1] and European Partnership for Energy and the Environment report [2]
The study showed the effect certain improvements have on increasing the efficiency of CO2 systems, old and new system solutions were compared in details; up to 40% increase in total COP was observed in the new systems compared to the old ones
Five supermarket refrigeration systems working with CO2 as refrigerant have been studied in details in the first part of this study [21]
Summary
Supermarkets are known as one of the largest emitters of high GWP refrigerants in Europe according to the Intergovernmental Panel for Climate Change special report [1] and European Partnership for Energy and the Environment report [2]. The amount of refrigerant charge in mediumand large-size supermarkets is in the range of hundreds to few thousands of kilograms and due to the long pipe runs and numerous piping connections, the leakage rate is reported to be 3–22% by different researches [1] The work presented in both papers (Parts I and II) is a comprehensive study with high level of details that facilitates drawing concrete conclusions on the performance of CO2 trans-critical versus conventional HFC systems in field installations. The work is combined with computer modelling which allows for annual energy use calculations that can be applied in different climates
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
