EU’s Tellurium-Free Thermoelectric Breakthrough Nears Market

According to Innovation News Network, the European START project has achieved breakthrough results in developing tellurium-free thermoelectric materials using tetrahedrite sourced from mining waste. The project produced a synthetic sample achieving a record figure of merit (zT) of 1.16 at 354°C, while mineral-derived samples from European mining waste reached zT=0.97, significantly outperforming typical literature values of 0.3-0.7. The team has processed over 40 kg of mineral concentrate using scalable High Energy Ball Milling and Upgraded-Field Assisted Sintering Technology, with the project now entering its final year and preparing to assemble its first prototype device. Life cycle assessment shows START’s modules generate only 63 kg CO2 equivalent compared to 329 kg for conventional BiTe modules, while also demonstrating dramatically lower human toxicity and mineral resource scarcity impacts. This progress marks a critical step toward establishing European leadership in sustainable thermoelectric technology.

The Critical Materials Revolution Europe Needs

The START project’s timing couldn’t be more strategic for European energy security. Tellurium, a key component in conventional thermoelectric materials, ranks among the most critical raw materials with China controlling approximately 70% of global production. This geopolitical concentration creates significant supply chain vulnerabilities for technologies ranging from waste heat recovery to specialized cooling applications. By leveraging tetrahedrite from mining waste, START addresses multiple strategic priorities simultaneously: reducing dependence on imported critical materials, valorizing industrial byproducts, and creating closed-loop material cycles that align with circular economy principles. The project’s success could establish a blueprint for how Europe approaches other material-critical technology domains.

Why the Performance Numbers Matter

The reported zT values of 1.16 for synthetic tetrahedrite and 0.97 for mineral-derived material represent more than incremental improvement—they cross critical performance thresholds that enable commercial viability. Most thermoelectric applications become economically feasible when zT exceeds 0.8-1.0, which START’s materials consistently achieve across both synthetic and waste-derived formulations. More importantly, the performance consistency between laboratory-scale production and processing 40 kg of material suggests the manufacturing approach is inherently scalable. The thermoelectric effect depends on complex material properties that often degrade when moving from gram to kilogram scales, making this demonstration of consistent performance particularly significant for industrial adoption.

The Manufacturing Innovation Behind the Breakthrough

START’s use of High Energy Ball Milling (HEBM) and Upgraded-Field Assisted Sintering Technology (U-FAST) represents a deliberate choice toward industrial scalability rather than laboratory optimization. Traditional thermoelectric material production often relies on processes like zone melting or spark plasma sintering that are energy-intensive and difficult to scale economically. HEBM enables efficient production of nanocrystalline powders with controlled composition, while U-FAST allows rapid consolidation without excessive grain growth that can degrade thermoelectric properties. The ability to produce 12 samples in a single sintering cycle demonstrates manufacturing efficiency that could translate to competitive production costs. This focus on scalable methods from the outset suggests the consortium understands that technical performance alone isn’t sufficient—commercial viability requires manufacturability.

The Environmental Case Beyond Carbon

While the carbon emission reductions are impressive—83% lower than BiTe modules—the broader environmental benefits may prove equally important for market adoption. The dramatically lower human toxicity (0.5 kg 1.4-DCB equivalent versus 12 kg for BiTe) addresses growing regulatory and consumer concerns about hazardous materials in energy technologies. Similarly, the mineral resource scarcity advantage (0.1 kg Cu equivalent versus 2 kg for BiTe) reflects better alignment with Europe’s resource efficiency goals. However, the Life Cycle Assessment also reveals important challenges: alumina substrates remain environmentally problematic due to energy-intensive production, and n-type legs still contribute significantly to mineral resource scarcity. These findings highlight that even breakthrough technologies require continued optimization across their entire material system.

The Road to Commercialization: Remaining Hurdles

Despite the impressive progress, significant challenges remain before START’s technology reaches widespread commercial deployment. The prototype assembly and testing phase will reveal crucial information about long-term stability, thermal cycling performance, and mechanical integrity under real operating conditions. Thermoelectric generators often face reliability issues at the interfaces between different materials, particularly under thermal stress—a challenge the COMSOL modeling attempts to address but which requires empirical validation. Additionally, while the environmental advantages are clear, economic competitiveness will depend on achieving production costs that can compete with established thermoelectric materials, despite their higher environmental impacts. The planned entity for matching European producers with end-users suggests recognition that technology push alone isn’t sufficient—market pull must be cultivated simultaneously.

Strategic Implications for European Industry

The START project represents a template for how Europe can leverage its research excellence to build strategic technology sovereignty. By developing alternatives to critical raw materials while simultaneously creating value from waste streams, the approach aligns with multiple European policy priorities. The follow-up COST Action (CA24120) indicates recognition that sustaining innovation requires ongoing community building and knowledge exchange beyond individual project timelines. Success could position European companies as leaders in sustainable thermoelectric technology for applications ranging from automotive waste heat recovery to industrial process optimization and even space power systems where reliability matters more than absolute cost. The project’s progress suggests Europe is developing a distinctive innovation model that combines technological excellence with circular economy principles and strategic autonomy.