Center for the Built Environment

Multi-zone variable air volume (MZ VAV) heating, ventilation, and air conditioning (HVAC) systems are commonly used in commercial buildings, but their performance varies widely, leading to a significant performance gap between best practice and typical operation. The supply air temperature (SAT) reset strategy significantly influences the energy efficiency of VAV systems. This paper presents the field implementation and validation of a novel SAT control method, Cost-Optimized Reset (CORE) in three commercial buildings in California. To evaluate the real-world performance of CORE, we conducted a measurement and verification (M&V) analysis using a randomized crossover trial approach over the course of the monitoring period. Energy consumption, HVAC operational parameters, and utility rates were analyzed and showed 5-22% energy savings in combined heating, cooling and fan energy, and 1-20% savings in related energy cost for CORE compared to the existing SAT reset strategy with no reported compromise to occupant comfort or system stability. The work also highlights implementation challenges and solutions and provides practical insights for scaling advanced control strategies across broader building portfolios. Through this field validation, CORE demonstrates its potential to serve as a cost-effective and scalable control strategy that aligns with the goals of improving energy efficiency and reducing carbon emissions in commercial buildings.