ACR Journal

CMYK / .ai CMYK / .ai CMYK / .ai acrjournal.uk 25 REFRIGERATION Adoption of doors on chilled display cases Adopting doors on chilled display cases is a relatively simple innovation, but it presents two significant energy reduction benefits. Firstly, they reduce the refrigeration system energy consumption and secondly, reduce a store’s heating demand due to the reduction in cold aisle air spillage. To measure the positive impact of doors, the graph below assesses the energy consumption of chilled open fronted display cases versus doored cases. Both the plant side and the direct electrical consumption (DEC) is included in the overall energy consumption modelling. Owing to the reduction in cold aisle spillage, the positive impact on a reduction in heating demand can be quantified. The graph below assesses the resulting di erence in refrigeration and heating energy consumption associated with the display cases; it has a profound e ect on the total energy consumption. Bringing HFO technology to market ASDA commenced an initial trial of HFO refrigerants in 2017. R454A was selected due to its similar capacity and P-to-T properties to HFC dominated synthetic refrigerants such as R407F and R448A. Along with possessing a GWP of 238, improved system performance has been achieved along with an energy saving of 4 per cent through the high isentropic e ciency of R454A. Alongside providing technical support in safely implementing HFO technology, WAVE also supported ASDA in determining the energy and wider environmental benefits of HFO refrigerants. The table below identifies the respective energy consumption and carbon emission of HFC, CO 2 and HFO refrigeration systems on a linear meter basis. The resultant e ect is that HFO refrigeration systems when considering ASDA’s low refrigerant leak rate has the lowest Total Environmental Warming Impact (TEWI). Respective energy consumption and carbon emission of HFC, CO 2 and HFO refrigeration systems on a linear meter basis ASDA is an advocate of all new technologies and selects its requirements based on a matrix of environmental, performance and safety based measures. Alongside stakeholders, it is currently replacing the CO 2 refrigeration systems with direct expansion HFO (R454A) systems at its store in Bootle. It is believed that Bootle will be the world’s first supermarket that will operate fully on HFO refrigeration technology. Reducing the impact