Balancing energy consumption and thermal comfort in buildings: a multi-criteria framework

The present study proposes a multi-criteria framework that focuses on two conflicting objectives typically encountered in building energy management systems: energy consumption of the air handling units (AHU) and thermal comfort of the occupants. In particular, an adaptive control of set points to AHU controllers is crucial to balance these objectives. This study, therefore, formulates the selection of set points as an optimization problem wherein the objectives are to balance thermal comfort with energy consumption while accommodating the distinct preferences of the decision maker (DM). Two multi-criteria decision-making formulations are considered to aggregate the objectives per the DM's preferences, i.e., conventional weight aggregation and epsilon-constraint. Finally, an online particle swarm optimization is used to solve such aggregated formulations and adapt the set points in real time as per the prevailing ambient conditions. The performance of the proposed framework is assessed by considering an experimentally validated model of an AHU plant and the real-time weather data of Auckland, New Zealand. The results of this investigation show that the proposed framework can successfully optimize the energy performance of an AHU plant while meeting the thermal comfort requirements specified by the DM.