Photo of Grant Wheeler.

Grant Wheeler

Researcher IV-Mechanical Engineering

Orcid ID

Grant joined NREL in November 2016 and works in the Building Energy Science Group. His expertise is in evaluation of heating, ventilating, air-conditioning, and refrigeration (HVAC&R) systems in the lab and field, development of advanced controls for HVAC&R systems, and determination of building load flexibility using HVAC&R systems. He most recently was the principle investigator for the design and construction of the Commercial Buildings Research Infrastructure within NREL’s Energy Systems Integration Facility, where he leads projects researching load flexibility of commercial buildings. He has also fully characterized two advanced commercial rooftop units and developed unique control strategies for a novel supply fan motor. Furthermore, he has experience with field evaluations, analyzing energy efficiency measures for variable refrigerant flow systems, commercial rooftop units, commercial refrigeration, and various chillers.

Grant started early in his career with laboratory experimentation of HVAC&R equipment, beginning with his graduate degree at Texas A&M University, where he developed an alternative test method for accurately and reliably measuring static pressure for HVAC equipment through a project with ASHRAE. He further developed his HVAC&R experience working at Carrier in Indianapolis, Indiana, where he developed residential air conditioners and heat pumps from ideation to assembly line. He also led a team to create universal quality metrics for all Carrier psychrometric rooms.

Grant has also held various other jobs, including commercial fisherman and commercial whitewater rafting guide, both of which gave him further appreciation for the outdoors and the role engineers play in reducing our impact on the environment.

Research Interests

Building load flexibility and grid interaction

Advanced HVAC&R


M.S. Mechanical Engineering, Texas A&M University

B.S. Mechanical Engineering, Montana State University

Featured Work

Evaluation of High Rotor Pole Switched Reluctance Motors to Control Condenser Fans in a Commercial Refrigeration System, NREL Technical Report (2019)

Experimental Design and Laboratory Characterization of a Medium- and High-Efficiency Rooftop Unit for use in Building Energy Simulations, International Refrigeration and Air Conditioning Conference (2018)

An alternative method for measuring air-handling unit static pressure following ASHRAE Standard 37: Scenario 1—horizontal ducts with elbows (RP-1581), Science and Technology for the Built Environment (2016)