Transforming wasted heat into electricity - and in a sustainable way? Yes, it's possible.

This is stated by Beatriz Santos, a PhD student in Materials Engineering at Técnico in the Technological and Nuclear Campus (CTN) in Loures, who participated in the congress "MATERIAIS 2025", held from July 1 to 3 at the Congress Center of the Instituto Superior Técnico. With the theme "Thermoelectric magnesium-based materials: exploring synthesis routes and outcomes", Beatriz's oral presentation, given on July 2, aimed to demonstrate that rare and toxic materials, such as tellurium, can be replaced by more abundant and sustainable compounds — like magnesium — capable of converting wasted heat into electrical energy.

According to Beatriz, it is estimated that "over 50% of global energy is wasted in the form of heat." The research work she presented shows that it is possible to recover some of these losses through thermoelectrics synthesized with "induction melting" — an approach that reduces the synthesis time from 8 hours to just 6 minutes, facilitating the transition from the laboratory to industrial scale, without compromising performance.

Beatriz has been developing her PhD at CTN under the co-supervision of researchers António Pereira Gonçalves from the Center for Nuclear Science and Technology, and Johannes de Boor from the German Aerospace Center, DLR.

The study presented brings science closer to its practical application, making energy-efficient solutions more accessible, both for industry and for the end consumer. «Details matter when we try to explain a phenomenon or achieve the best possible outcome. But, in the face of the urgency to find solutions to global energy challenges, I believe it is more important to focus on something functional and useful today», emphasizes Beatriz Santos.

Learn more about the congress here: https://congressomateriais.pt/