A field study of space heating control using acceptable set-point temperature estimation: Winter experiment in Japan office

Abstract

Energy conservation for space heating is important because a large portion of total energy consumption is used for space heating in cold regions. For example, space heating accounts for 40% and 18% of energy consumption in non-residential buildings in the EU and Japan, respectively. We have recently proposed a new space-heating control method that estimates acceptable set-point temperature based on survival analysis of historical data on set-point temperature adjustments by occupants in a space. By using survival analysis to estimate acceptable set-point temperatures, the proposed method adjusts the set-point temperature of the space to the estimated minimum acceptable value. We present the results of a field study of the proposed method which was performed in winter 2017-2018 in Japan. In this study, we applied the proposed method in two office rooms and assessed energy savings and occupant acceptance ratios for the proposed method. Performance evaluation experiments were carried out twice in the winter. The energy-saving rate was from 3% to 45%, and the occupant acceptance ratio exceeded 80% in both experiments. The results obtained in this study confirm that the proposed method is acceptable to occupants, while having a possibility of energy-saving.