Groundbreaking Eco-Friendly Cooling Device Sets New Performance Benchmark
eco friendly cooling device performance record
HKUST unveils a groundbreaking cooling device that achieves a world-record 75 K temperature lift and a 48% increase in efficiency, utilizing sustainable materials. Researchers from the Hong Kong University of Science and Technology’s School of Engineering have engineered an innovative, environmentally-conscious refrigeration system that sets new benchmarks in cooling performance.
With a significant 48% enhancement in efficiency, this novel elastocaloric cooling technology holds immense potential for accelerating its commercialization and tackling the environmental challenges posed by conventional cooling systems.
Innovations and Challenges in Cooling Technology
Conventional vapor compression refrigeration relies heavily on refrigerants with high global warming potential. In contrast, solid-state elastocaloric refrigeration, which harnesses latent heat through the cyclic phase transition of shape memory alloys (SMAs), offers a sustainable alternative.
These SMAs are not only free from greenhouse gases but are also 100% recyclable and energy-efficient. However, a significant hurdle in commercializing this emerging technology has been its relatively modest temperature lift, ranging between 20 and 50 K—a crucial performance metric indicating the device’s ability to transfer heat from a cooler source to a warmer sink.
A World Record in Cooling Efficiency
Addressing this challenge, a research team led by Professors Sun Qingping and Yao Shuhuai from the Department of Mechanical and Aerospace Engineering has developed a multi-material cascading elastocaloric cooling device. Constructed from nickel-titanium (NiTi) shape memory alloys, this device has shattered previous world records in cooling performance.
The team carefully selected three distinct NiTi alloys, each with unique phase transition temperatures, to function at the cold, intermediate, and hot ends of the device.
By aligning the operational temperatures of each segment with its respective phase transition temperature, they successfully expanded the device’s superelastic temperature window to over 100 K. Consequently, each NiTi unit functioned within its optimal temperature range, markedly improving the device’s cooling efficiency.
The multi-material cascading elastocaloric cooling device achieved an unprecedented 75 K temperature lift on the water side, eclipsing the former world record of 50.6 K. Their groundbreaking research was recently published in Nature Energy.
Future Prospects and Environmental Impact
Building on their success in developing elastocaloric cooling materials and systems—bolstered by numerous patents and publications in leading scientific journals—the research team aims to further advance high-performance shape memory alloys and devices.
Their future endeavors will focus on sub-zero elastocaloric cooling and high-temperature heat pumping applications. They are committed to refining material properties and creating highly energy-efficient refrigeration systems, driving the commercialization of this cutting-edge technology.
As space cooling and heating account for 20% of the world’s total electricity consumption—and are projected to become the second-largest source of global electricity demand by 2050—this innovation arrives at a critical juncture.
“With ongoing advancements in materials science and mechanical engineering, we are optimistic that elastocaloric refrigeration will emerge as the next-generation solution for green and energy-efficient cooling and heating, meeting the vast global demand for refrigeration while addressing the pressing need for decarbonization and climate change mitigation,” stated Professor Sun.
Reference
“A multi-material cascade elastocaloric cooling device for large temperature lift” by Guoan Zhou, Zexi Li, Qiuhong Wang, Yuxiang Zhu, Peng Hua, Shuhuai Yao, and Qingping Sun, 23 May 2024, Nature Energy. DOI: 10.1038/s41560-024-01537-3.
