Energy efficiency improvement solutions for supermarkets by low‐e glass door and digital semi‐hermetic compressor

Abstract

This research presents an energy efficiency improvement solution for supermarkets with the use of low‐E glass doors for open refrigerators and a digital semi‐hermetic compressor to fix the speed of semi‐hermetic compressors. The impact of a door’s installation causes its load to be re-duced by 40%, and the compressor shuts down frequently, which decreases its lifetime. In order to ensure that energy‐saving solutions do not affect maintenance costs, the installation of a digital semi‐hermetic compressor is proposed to lower costs and save energy. Our economic results from tests carried out at a 3000 square meter supermarket, which was open from 6:00 am to 12:00 am and in which we installed 82 doors on 15 open refrigerators, showed a 1.1‐year payback period with an energy saving rate of 192,220 kWh/year for store No.1 (R22) and in which we installed 80 doors on 15 open refrigerators, showed a 1.4‐year payback period with an energy saving rate of 171,185 kWh/year for store No.2 (R404A). The energy‐saving effects of the digital semi‐hermetic compres-sor, which fixes the speed of the semi‐compressor and solves the problem of impact from fridge door installation, showed a 2.9‐year payback period with an energy saving rate of 26,890 kWh/year for store No.1 (R22) and showed a 2.9‐year payback period with an energy saving rate of 26,571 kWh/year for store No.2 (R404A). The results of store No.1 (R22) and store No.2 (R404A) showed no differences. This research is an extension of an energy‐saving project that can be carried out on a continuous basis, increasing the efficiency of energy use and being a sustainable source of energy conservation.