17 October 2006

Development of automatic drink vending machines with CO2 refrigerant

The authors have developed a technology for applying carbon dioxide as refrigerant to refrigerating system
(unit) of vending machines of cold(and hot) drinks in order to reduce greenhouse gas emissions and power
consumption. In the refrigeration system carbon dioxide becomes supercritical at high ambient temperatures,
resulting in lower operation effi ciency. The authors therefore optimized the refrigerating cycle by employing
two stage compressor, and developed a new fi n-shaped evaporator, thus increasing operation effi ciency and
reducing power consumption by 9%. Moreover, the authors have confi rmed that simultaneous heating and
cooling of cans and bottles with heat pump mode can signifi cantly reduce power consumption.