Adaptive and distributed operation of HVAC systems: Energy and comfort implications of active diffusers as new adaptation capacities. (December 2020)

• Record Type: Journal Article
• Authors: Jazizadeh, Farrokh; Joshi, Vedant; Battaglia, Francine
• Is Part Of: Building and environment. Volume 186(2020)
• Publication Date: 2020-12
• Subjects: Adaptive operations -- HVAC systems -- Load flexibility -- Energy efficiency -- Smart buildings -- Adaptive diffuser -- Robotic diffuser -- Comfort-driven HVAC operations; Buildings -- Environmental engineering -- Periodicals; Building -- Research -- Periodicals; Constructions -- Technique de l'environnement -- Périodiques; Electronic journals; 696
• DOI: 10.1016/j.buildenv.2020.107089
• Languages: English
• ISSNs: 0360-1323

Abstract

Abstract: Human-aware HAVC operations have been shown to be effective in improving energy efficiency, which is constrained by the HVAC system configuration and operational logic. These constraints can result in a lack of operational flexibility, which in turn reduces the adaptation capacity for energy efficiency. Therefore, in this study, we investigated the energy efficiency implications of novel adaptive capacities for HVAC including the use of proposed active diffusers, which add to the dynamics of the HAVC systems by adjusting the behavior of diffusers using two modalities of (1) binary actuation of air flow (turning flow on and off), and (2) adjusting the flow direction to target individual needs in an environment. Computational fluid dynamics was used to model and simulate the behavior of a "real-world" thermal zone to evaluate five scenarios of adaptive operations using distributed feedback from the environment, as well as active diffusers. Three scenarios used binary actuation at the thermal zone (collection of rooms) level, and two examined the adaptive operations at the diffusers level. Moreover, we examined the integration of distributed feedback at occupant locations into the control loop using averaged temperatures (in the first three scenarios) and individual-level feedback (in scenarios with diffuser level actuation). The coupling of distributed feedback and independent directional flow at the diffuser level considerably improved thermal comfort while reducing energy demands by ~25%—reflecting a considerable impact on improved energy efficiency. These findings demonstrate the potentials that artificial intelligence frameworks could bring about by enabling autonomous adaptive operations. Highlights: Investigated the energy efficiency implications of novel adaptive HVAC operations. Introduced the concept of active diffusers that increase diffuser flexibility. Expanded flexibility by directional flow, binary actuation, and distributed sensing. Binary-controlled directional flow with distributed feedback was the most effective. Improved the thermal comfort and reduced energy demands by almost 25%.