Researchers at the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, have developed a revolutionary solid-state thermoelectric refrigeration technology that significantly outperforms current systems. Using nano-engineered materials called Controlled Hierarchically Engineered Superlattice Structures (CHESS), the team has achieved twice the efficiency of traditional bulk thermoelectric materials—offering a scalable, energy-efficient alternative to conventional compressor-based cooling systems.
As the global demand for compact, reliable, and eco-friendly refrigeration solutions increases—driven by population growth, urbanization, and expanding digital infrastructure—this advancement could redefine the cooling industry.
Published in Nature Communications, the work represents a collaboration between APL researchers and refrigeration engineers from Samsung Electronics. The CHESS material is the result of more than ten years of research at APL. Originally developed for national security applications, it has since found use in prosthetic cooling therapies and earned an R&D 100 award in 2023.
“This real-world demonstration of refrigeration using new thermoelectric materials showcases the capabilities of nano-engineered CHESS thin films,” said Rama Venkatasubramanian, principal investigator and chief technologist for thermoelectrics at APL. “It marks a significant leap in cooling technology and sets the stage for large-scale, energy-efficient applications.”
Unlike conventional refrigeration, which relies on bulky, mechanical systems and environmentally harmful chemical refrigerants, thermoelectric cooling transfers heat using electrons in semiconductors. The benefits? No moving parts, no refrigerants, and a compact, silent design.
However, traditional bulk thermoelectric materials—often used in small gadgets like mini-fridges—have long struggled with efficiency, limited heat-pumping capacity, and scalability. The CHESS materials overcome these barriers with precisely engineered nano-structures that boost performance and enable semiconductor-style manufacturing.
In standardized refrigerator testing, APL’s CHESS-based modules demonstrated:
- 100% improvement in material-level efficiency at room temperature (25°C)
- 75% boost in device-level efficiency
- 70% gain in full-system refrigeration efficiency
These results represent a dramatic leap forward and were validated by Samsung’s team through rigorous modeling and thermal performance analysis.
Another key advantage of CHESS technology is its ultra-thin profile—just 0.003 cubic centimeters per refrigeration unit, about the size of a grain of sand. This minimal material usage allows for mass production using established semiconductor tools, enabling cost-effective scaling.
“This thin-film technology has the potential to evolve like lithium-ion batteries did—from powering handheld devices to large-scale infrastructure,” said Venkatasubramanian.
The CHESS materials were fabricated using metal-organic chemical vapor deposition (MOCVD), a method widely employed in producing commercial solar cells and LEDs. According to Jon Pierce, who leads MOCVD operations at APL, this approach is not only proven but ideally suited for high-volume, low-cost manufacturing.
Beyond advanced cooling, CHESS thermoelectric materials show promise in energy harvesting and thermal management for electronics. APL plans to expand partnerships to optimize the materials further—aiming to match or surpass the performance of conventional mechanical refrigeration systems.
With this milestone, the future of efficient, solid-state cooling—and potentially greener HVAC systems—looks closer than ever.
By Impact Lab
