The energy saving opportunity of supermarket refrigeration systems using subcooler between the medium-temperature (MT) refrigeration system and the low-temperature (LT) refrigeration system has been identified in the previous work This paper presents a model-based comprehensive analysis on the subcooler design The optimal subcooling control is discussed as well With optimal subcooler size and subcooling control the maximum energy savings of integrated two-temperature supermarket refrigeration system using R404A or R134a as working fluid can achieve 27% or 20% respectively The load ratio of MT to LT system and the operating conditions have considerable impact on the energy savings (C) 2010 Elsevier B V All rights reserved