“Dynamic controls for hybrid and efficient RTUs”
This paper examines the use of dynamic control systems to optimize operating costs and reduce emissions in commercial hybrid (dual-fuel) rooftop units (hRTUs), while also highlighting the energy savings delivered by efficient rooftop units (eRTUs). Hybrid RTUs can switch between electric heat pump and gas furnace modes, providing operational flexibility that supports either economic or environmental goals. eRTUs further enhance efficient energy delivery through advanced design features. To evaluate the performance of dynamic controls using real-time utility tariff data and regional emission factors via cloud integration, four hRTUs were installed in Virginia, USA for baseline and demonstration monitoring from August 2024 to August 2025. The study compares dynamic control strategies and energy delivery with conventional static switchover methods and gas-only furnace baselines, focusing on cost savings and emissions reduction. The paper will present the outcomes of implementing dynamic control systems and efficient design elements, emphasizing improvements in cost-effectiveness and environmental impact through real-time, data-driven decision-making. It also addresses limitations encountered during the study and offers recommendations for enhancing the feasibility and performance of such systems in future commercial HVAC applications. This research supports the advancement of smarter, more adaptive HVAC technologies aligned with variable energy pricing and evolving emissions standards.