New HVAC Technologies Lower Energy Costs for Businesses

Energy-efficient building technologies play a critical role in helping American consumers and businesses lower their energy costs. 

With support from the Department of Energy’s (DOE’s) Better Buildings and Better Plants Initiative, Pacific Northwest National Laboratory (PNNL) partnered with several other national laboratories as well as multiple major heating, ventilation, and air conditioning (HVAC) companies to develop and validate a new generation of advanced HVAC units for commercial buildings that exceed the performance of existing product lines. These advanced, fuel-flexible rooftop units (RTUs) are designed to operate efficiently in sub-freezing temperatures and reduce HVAC costs by up to 50% compared to currently available systems. 

Advanced units are being deployed on commercial buildings to validate their performance in real-world conditions before commercial rollout. 

“By confirming performance before widescale rooftop installation—where a single crane lift can cost $30,000—PNNL is helping manufacturers and building owners de-risk investment in new technologies that can lower their energy bills,” said Michael Myer, project lead at PNNL.

Industry partners included HVAC manufacturers AAON, Bosch, Carrier, Daikin, Lennox, LG, Rheem, and Trane. The National Laboratory of the Rockies, Oak Ridge National Laboratory, and Argonne National Laboratory also contributed to the development of the next-generation RTUs.

Advancing RTUs for the real world

RTUs are one of the most common HVAC systems in commercial buildings, servicing more than 2.5 million buildings in the United States, so improving their performance could significantly reduce energy use and lower costs for businesses. But new technologies in any industry carry some inherent risks for business owners that can make them less likely to be used. 

DOE’s Better Buildings and Better Plants Initiative launched the Commercial Building HVAC Accelerator in 2024 to help reduce the costs of commercial HVAC. The challenge brought together manufacturers and commercial building owners representing over 500 million square feet of real estate, including Target, Amazon, and Lowe’s retail stores and facilities. PNNL played a key role in the challenge to de-risk new technology prototypes by rigorously testing them in environmental chambers that simulate rooftop conditions as cold as –10°F. 

National lab researchers developed a performance specification for next-generation RTUs with improved heating, fuel flexibility, and flexible load controls that allow consumers to optimize energy use throughout the day for greater savings, and manufacturers provided input on that specification. With this information, the team developed testing methods, defined performance criteria, and evaluated new prototypes from the manufacturers.

“This isn’t theoretical performance,” said Brent Stockton, Executive Director of Engineering at AAON. “Alpha Class EXTREME [AAON’s technology] is running in real buildings, in real climates. Passing lab verification simply confirms what our customers already see in the field.”

Now, the technologies are being tested in the real world—including at a Lowe’s in Zionsville, Indiana, and on PNNL’s own campus—with more than a dozen installations complete. Commercial rollouts by some industry partners, including domestic manufacturing of new systems, have already started.

“These field trials are the final step before launching a high-performance product designed to strengthen U.S. commercial buildings,” said Heidi Gehring, Managing Director of Light Commercial at Carrier. 

Low-cost thermostat improvements for RTUs

In addition to advancing new RTU technologies, PNNL is also supporting low-cost thermostat solutions for building owners who aren’t ready to replace their entire HVAC systems. There are readily-available retrofit options on the market—like advanced thermostat controls—that can lower energy bills for small building owners, but they haven’t gained much traction in the past 15 years. To understand why, researchers recently completed a three-year observational study of the human barriers to retrofits of existing RTUs. 

The team observed multiple installation teams perform retrofits of over 30 RTUs on different buildings to identify opportunities to improve performance and cost savings. With this information, they developed a set of recommendations for building owners, installers, manufacturers, and utilities that help streamline retrofits to improve RTU performance. 

“We found that regular maintenance by owners combined with installation best practices from installers and user-friendly configuration steps by manufacturers can prevent delays during retrofits,” said Meghan McNulty, PNNL project lead. “Faster and more successful retrofits benefit everyone. Owners can see lower energy bills, installers can see increased profit margins, and everyone’s confidence in the new technology increases.”    

This work was supported by DOE’s Office of Critical Minerals and Energy Innovation, Building Technologies Office.