Appropriate indoor climate for environmentally sustainable Supermarkets – Measurements and Questionnaires

Half the electricity use in supermarkets derives from the display of refrigerated food. Climate influences the performance of the cabinets and their energy use as well as the thermal comfort of people and the temperature quality of the food. This work is an interdisciplinary study of perceived comfort in relation to measured local climate. The aim is to define an appropriate climate and to improve energy efficiency with maintained or even better climate for goods, staff and customers. Perceived comfort depends on thermal balance of the whole body. ISO7730 is valid only for situations where people spend a longer time. This study involves temporary situation of supermarket shopping. Perception data have been obtained by means of a questionnaire based on ISO10551. The results show that according to ISO7730 people should be dissatisfied with their thermal comfort. The questionnaires (ISO10551), however, indicate that the thermal conditions are acceptable