Optimization of HVAC Energy Efficiency through Minimum Diffuser Airflow Control in High-Ambient Regions
DOI:
https://doi.org/10.70917/jcc-2026-010Keywords:
HVAC energy savings, Variable air volume (VAV) systems, Diffuser airflow control, High ambient temperature, Energy efficiency, Building automation systems (BAS)Abstract
This study addresses the persistent issue of energy inefficiency in Variable Air Volume (VAV) HVAC systems operating in hot-arid climates, specifically focusing on the impact of reducing minimum diffuser airflow setpoints in commercial office buildings in Kuwait. To evaluate the feasibility of airflow rescheduling as a cost-effective energy-saving measure, a field intervention was implemented across six Air Handling Units (AHUs) serving over 200 VAV terminals in two government buildings. Using real-time energy metering, Building Automation System (BAS) control logic, and occupant thermal comfort surveys, the study measured system performance before and after the adjustment of minimum airflow rates to 30% and 25% of design capacity. Results showed energy savings of 18–25% across all monitored AHUs, with average chilled water and fan power consumption reduced by 21.4%. Indoor environmental conditions remained within ASHRAE comfort and air quality standards, with over 87% of occupants reporting satisfaction. Minimum diffuser airflow rescheduling offers a significant, low-investment opportunity for HVAC energy savings in commercial buildings located in hot climates. The measured energy reductions confirm the effectiveness of this strategy without major modifications to existing systems. Broader implementation across similar facilities could contribute substantially to energy conservation goals. This study demonstrates that significant HVAC energy savings, ranging from 15–20%, can be achieved through minimum diffuser airflow rescheduling, even in extreme high-ambient environments like Kuwait.
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Copyright (c) 2026 K J Sreekanth, Fotouh Al-Ragom, Sara Al-Osaimi, Ruba Al-Foraih, Aarthi Elumalai (Author)
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