SYDNEY, Australia – Scientists at the Queensland University of Technology (QUT) have announced a significant advancement in renewable energy, developing an innovative material capable of converting waste heat into electricity with over 13% efficiency. This breakthrough, detailed in the journal Energy & Environmental Science and released on Thursday, September 18, 2025, represents a major step towards harnessing the vast amounts of energy currently lost as heat from industrial processes, vehicles, and power plants.
The research team, led by Professor Zhi-Gang Chen and Dr. Nan-Hai Li from QUT’s School of Chemistry and Physics, engineered a new thermoelectric material by incorporating manganese into silver copper telluride. This modification has resulted in a prototype device that delivers a conversion efficiency exceeding 13%, positioning it among the most effective technologies available for transforming thermal energy into usable electricity.
The Breakthrough Material: Manganese-Doped Silver Copper Telluride
The core of this achievement lies in the novel material developed by the QUT team. By adding manganese to a silver copper telluride compound, researchers observed a remarkable enhancement in its thermoelectric properties. This seemingly minor alteration created a material that outperforms previous candidates in its class.
Professor Chen highlighted the significance of the 13% conversion rate, explaining that for every 100 units of heat energy applied to the device, approximately 13 units are successfully converted into electricity. While this might not sound substantial to the uninitiated, it is a very high number for thermoelectric materials, which often achieve only a few percent efficiency.
Understanding Thermoelectric Conversion
Thermoelectric devices operate on the principle of the Seebeck effect, where a temperature difference across a material generates an electric voltage. Conversely, the Peltier effect describes how an electric current can create a temperature difference. The efficiency of these materials is crucial for practical applications, particularly in capturing and converting waste heat. A key challenge in developing efficient thermoelectric materials is finding substances that are simultaneously good electrical conductors and poor thermal conductors—a combination rarely found in nature.
The ability of a material to convert heat to electricity is often quantified by its dimensionless figure of merit, known as ZT. Higher ZT values indicate better performance. The QUT team’s success demonstrates an optimized balance of these properties in their new manganese-doped silver copper telluride.
Paving the Way for Greener Energy and Industrial Efficiency
The potential applications for this technology are far-reaching and critical for global sustainability efforts. Over 65% of the energy produced worldwide is lost as waste heat. By integrating this new thermoelectric material into existing systems, industries could reclaim energy that would otherwise be vented or dissipated, turning it into a valuable power source.
Key areas where this technology could have a transformative impact include:
- Industrial Processes: Factories and power plants generate immense amounts of waste heat. Efficient thermoelectric generators could capture this heat and convert it into electricity, significantly improving energy efficiency and reducing operational costs.
- Automotive and Transportation: Vehicle engines, ships, and tankers produce substantial waste heat. Thermoelectric devices could convert this heat into electrical power, boosting fuel efficiency and reducing emissions.
- Clean Energy Goals: Recovering waste heat contributes directly to reducing fossil fuel consumption and lowering carbon emissions, supporting global carbon neutrality targets. Because thermoelectric devices have no moving parts and produce no chemical reactions or emissions, they offer a clean and reliable source of energy.
Broader Advancements in Thermoelectrics
The QUT breakthrough is part of a broader wave of innovation in thermoelectric materials research globally:
- Record-Breaking Tin Selenide: In August 2021, researchers from Northwestern University in the U.S. and Seoul National University in Korea developed polycrystalline tin selenide, boasting a heat-to-electricity conversion efficiency of nearly 20%, achieving a ZT of 3.1 at 783 Kelvin. This material is considered highly promising for industrial waste heat recovery due to its high efficiency and good mechanical properties.
- High-Entropy Materials by Penn State: Scientists at Penn State, through a study published in Joule around September 2024, have created high-entropy materials that achieved 15% conversion efficiency in a prototype thermoelectric generator. Earlier, in April 2023, the team demonstrated 15.2% efficiency in a single-leg device, indicating that these new materials could make thermoelectric generators as efficient as other renewable energy sources like solar.
- CHESS Thin Films for Cooling: More recently, around September 2025, the Johns Hopkins Applied Physics Laboratory (APL) unveiled Controlled Hierarchically Engineered Superlattice Structures (CHESS) thin films that nearly double the refrigeration efficiency of traditional thermoelectric materials at room temperature. This development, published in Nature Communications, has significant implications for compact, reliable, and energy-efficient cooling technologies, as well as energy harvesting.
These parallel developments underscore a period of rapid progress in thermoelectric technology, moving closer to widespread commercial viability.
Challenges and Future Outlook
Despite these impressive gains in efficiency, challenges remain in bringing thermoelectric technology to widespread use. Factors such as cost-effectiveness, scalability of manufacturing, and long-term stability under harsh operating conditions are critical considerations. Current commercially available thermoelectric devices typically boast efficiencies of 5% to 6%. The advancements demonstrated by QUT, Penn State, and other institutions signify that thermoelectric materials are becoming increasingly competitive with conventional power generation technologies, especially at smaller scales or for specific waste heat recovery applications.
The ongoing research into novel materials, nanostructuring techniques, and improved device designs is continuously pushing the boundaries of what’s possible. As these efficiencies continue to climb, thermoelectric materials are poised to play an increasingly vital role in sustainable energy solutions and efficient thermal management systems, helping to realize a future where waste heat is no longer simply lost, but rather a valuable resource.
