Temperature Periodic Modulation Doubles the Power Output of Thermoelectric Generators

Dario Narducci; Antonio Mazzacua; Federico Giulio

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arXiv · 2609.33425

Temperature Periodic Modulation Doubles the Power Output of Thermoelectric Generators

Dario Narducci·Antonio Mazzacua·Federico Giulio

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Abstract

Thermoelectric heat harvesting provides in principle a flexible, reliable way to convert heat into electric energy, thus recovering waste heat and powering off-net devices. However, thermoelectricity conversion efficiency is still low, despite the major efforts deployed over the last two decades to improve materials performances. A largely unexplored opportunity to increase harvesting efficiency is offered by converting heat flux dynamically. It was shown [D. Narducci et al., Mater. Today Phys. 54, 101713 (2025)] that when the temperature of the heat source is sinusoidally modulated, this leads to an increase of the maximum power by up to 50 %. In this paper we show how this approach can be further and significantly enhanced. We found that sinusoidal modulation can be outperformed by a different periodic modulation, leading to an increase of the power output by up to 100 % compared to the stationary case. Furthermore, we extended our analyses beyond the constant-property approximation, showing that the power output enhancement is robust, applying to any real material where the temperature dependence of all phenomenological coefficients is accounted for. This major power output enhancement offers a novel, immediately applicable pathway to overcome the efficiency limits of thermoelectric devices.

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Dario Narducci, Antonio Mazzacua, Federico Giulio. 2026-09-27. Temperature Periodic Modulation Doubles the Power Output of Thermoelectric Generators. https://arxiv.org/abs/2609.33425

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