Abstract

It is estimated that building energy consumption (BEC) accounts for one-third of the total global energy consumption, and Heating, Cooling, and Air-conditioning (HVAC) accounts for almost half of the energy consumption of buildings. To efficiently achieve more energy saving from the HVAC systems, narrowing the gap between the actual energy consumed and the demanded heating and cooling loads is found to be a promising strategy. Therefore, occupancy-driven HVAC management is attracting great attention. On the other hand, future smart buildings will have the ability to detect and locate the occupants, and adjust the HVAC system accordingly, which is expected to result in considerable energy savings. This research proposes a local climate control strategy in open space, such as shared offices, by dividing the space into zones according to the number of HVAC terminal units and adjusting the operation of each terminal unit based on occupants’ preferences and presence in the zone. To evaluate the performance regarding energy consumption and occupancy thermal comfort, and the feasibility of the proposed local climate control, three case studies are implemented. The occupancy presence pattern is captured by a Bluetooth Low Energy (BLE)-based tracking system. Based on a four-week test carried out in a graduate laboratory in Concordia University, the occupancy profiles and different HVAC operation scenarios are created as the inputs of the building energy simulation. The simulation is run for three months for cooling and the results show that, with the adoption of the proposed local climate control strategy, 15% or 36% of the energy consumption can be saved compared with applying a dynamic schedule using a motion detector or a fixed schedule, respectively. In addition, the occupants’ comfort level can be increased by an average of 6%. In addition, sensitivity analysis is conducted with respect to the factors affecting the effectiveness of the proposed climate control strategy and the HVAC setpoint temperature. It is concluded that the proposed local climate control strategy is effective in reducing the energy consumption and improving occupancy thermal comfort, however, the extent of the effectiveness depends on factors of building properties, occupancy attributes, and HVAC operation.