A decentralized method for energy conservation of an HVAC system

Building, heating, ventilation, and air-conditioning (HVAC) consumes nearly 48% of the entire building energy of the world. Improvement in the control strategy of an HVAC system can result in substantial energy savings, which is the motivation behind this research. In this study, a decentralized method is proposed to search for a good-enough control strategy to reduce the energy consumption of a typical HVAC system consisting of cooling towers, chillers, pumps, and air handling units (AHUs). The method is then compared to a centralized method. In addition to energy consumption, indoor environmental factors such as temperature and humidity are considered in the new method to meet the requirements of human comfort. We introduce experimental conditions for feasibility and the crude energy index in the decentralized method to reduce the computational time. The improved HVAC system was able to save 34% (per 12 h) on energy consumption and the average computational time was reduced to 1247.5 s, which proves the efficiency and effectiveness of the decentralized method and the performance of the proposed control strategy.