Bio
Dr. Joseph Rendall is an R&D associate staff member in the Multifunctional Equipment Integration Group at the U.S. Department of Energy’s Oak Ridge National Laboratory (ORNL). Dr. Rendall is the research advisor for the Building Technologies Research and Integration Center’s Residential Water Heating and Appliance Laboratory. His patents include: State of Charge Sensor for Phase Change Material Thermal Energy Storage (US20240310082A1), Hydraulically Opened Cone Vertical Tube Diffuser with Slanted Anti‑Siphon Hole (US11768012B2), and Density Controlled Phase Change Capsules, (US20230082570A1). He has also developed a heat exchanger technology that was a finalist for an R&D 100 award.
Dr. Rendall is an expert in thermally stratified water and its impact on water heating, specifically regarding heat pump water heater efficiency. He develops new water heating and appliance technologies that use vapor and non-vapor compression technologies to reduce energy consumption, carbon footprint, and costs. His skills include experimental prototype evaluations, 1D and 3D modeling, and innovation in thermal energy systems, fluid systems and heat pump design. He has authored 15 publications in water heating, heat pumps and thermal energy storage.
Dr. Rendall also has extensive volunteer experience, including with Engineers Without Borders in Bolivia and as a Peace Corps volunteer in Uganda. In Uganda he taught thermodynamics, heat transfer, and experimental physics to future secondary physics teachers.
Dr. Rendall received his PhD in sustainable energy systems engineering from Texas A&M University – Kingsville and his MS and BS in Architectural Engineering from the University of Kansas.
Trademarks and Patents
Hydraulically opened cone vertical tube diffuser with slanted anti-siphon hole [US11768012B2]
Density controlled phase-changing material (pcm) spheres for increased heating power and optimal delivery temperature in hot-water tanks [US20230082570A1]
State of charge sensor for phase change material thermal energy storage [application recently submitted]