A novel operation approach for the energy efficiency improvement of the HVAC system in office spaces through real-time big data analytics

Since a traditional centralized control system (e.g., building energy management system) with a fixed schedule and manual control is not appropriate to irregularly occupied rooms, it is expected to have a large amount of energy saving potential in operating the HVAC system. To overcome this challenge, this study aimed to develop a novel operation approach for the energy efficiency improvement of the HVAC system in office spaces. The real-time indoor environmental indicators were collected and analyzed to evaluate the current operation status of the HVAC system as well as to propose a novel control strategy in two ways. The significant findings can be illustrated as follows. First, it could be stated that occupants would tend to establish a lower set-point temperature for a cooler indoor environment. To solve this issue, a basic control strategy was proposed to detect the anomaly detection of the HVAC system and to automatically adjust the indoor temperature within a preferred range. Second, it could be evaluated that the HVAC system would be kept operating since occupants would forget to turn off the HVAC system after the meetings. To solve this issue, an advanced control strategy was proposed to operate the automatic on/off control of the HVAC system by considering the indoor temperature and CO₂ concentration in real time. The proposed strategies can contribute to a large amount of energy savings in operating the HVAC system of irregularly occupied spaces.