Growing up in China, Zhiyao Yang remembers the unbearable summer heat as his city enforced “no electricity days” to counteract the heightened demand for air-conditioning. The immense energy consumption of air-conditioning systems made a lasting impression.

After obtaining a master’s degree in civil engineering from Purdue University, Yang applied to the Post-Master’s Research Associate Program at Oak Ridge National Laboratory (ORNL) to support projects promoting energy efficiency.

ORNL Post-Master's Research Profile: Zhiyao Yang

Zhiyao Yang, a participant in the Post-Master’s Research Associate Program at Oak Ridge National Laboratory, studied methods to increase the use of low-grade energy resources.

His master’s thesis involved collaboration between Purdue and ORNL, so he was familiar with the high caliber of research being conducted at the lab. “When I found this program that would allow me to learn alongside the best in the field and contribute to the exciting research at ORNL, I applied without hesitation,” Yang said.

Alongside his mentor, Xiaobing Liu, Ph.D., Yang evaluated the potential of several innovative thermal energy storage and transportation systems for air-conditioning applications. Currently, 24 percent of primary energy consumption in the United States is used for thermal application under 120 degrees Celsius, among which heating, ventilation and air-conditioning systems are major contributors.

“There is an enormous amount of low-grade thermal energy across the country, including heat from solar and geothermal resources, and waste heat from industrial processes,” Yang explained. “If we can come up with innovative thermal systems to utilize these otherwise abandoned energy sources, then we can alleviate the demand for fossil fuels, reduce the carbon footprint and promote energy efficiency and sustainability within our society.”

Yang designed, developed and evaluated various systems with the intention of creating systems that can economically bridge the gap between the remote low-grade energy resource and in-town thermal energy demand. After collecting data, his goal shifted to determining the energy-saving potentials and the technical challenges associated with these systems.

“Once applied, these systems are able to make use of the otherwise deserted renewable geothermal energy sources, saving thousands of dollars in electricity bills each year while cutting the primary energy consumption and carbon emissions from air-conditioning by more than one half,” Yang said.

With his team, Yang published conference papers detailing his research at the Stanford Geothermal Workshop and the Refrigeration and Air Conditioning Conference at Purdue University. Additionally, the research was presented during the Oak Ridge Postdoctoral Association Research Symposium at ORNL.

Upon entering the program, Yang was unsure of the career path he would follow after his participation. However, studying sustainable energy solutions at a national laboratory inspired Yang to continue his education in a doctoral program.

“The Post-Master’s program is an absolutely rewarding experience,” Yang said. “I’ve had the opportunity to contribute to challenging projects, discuss concepts with the brightest minds in the field and practice my presentation skills.”

The former Post-Master’s Research Associate Program was administered by the Oak Ridge Institute for Science and Education (ORISE) for the U.S. Department of Energy.