This paper describes a portion of a study, which investigated the reduction of energy consumption in grocery stores in a hot and humid climate. Thefirst part of the study investigated the maximum possible savings that can be obtained on implementing energy efficiency measures in a grocery store.The second part of the study took a step further and examined the option of combined heat and power (CHP) technologies to power the grocerystore and a portion of the community to further reduce the energy consumption of the grocery store and the community. This paper presents thedevelopment of a base-case simulation model for a grocery store and the procedure developed to calibrate this model. The simulation model was thenused in the assessment of energy efficiency measures in the grocery store. The simulation model was developed using a whole building energysimulation program with capabilities for modeling commercial refrigeration equipment, and information from a case-study grocery store situated ina hot and humid climate. The calibration process was conducted using both statistical and graphical indices using data obtained from monthlyutility bills as well as data available from an on-site monitoring system implemented in the case-study store. The simulation model was calibratedto a RSME of 32.15, CV(RMSE) of 0.07 and MBE of 0.84.