Barium Calcium Zirconium Titanate Thin Film-Based Capacitive Thermoelectric Converter for Low-Grade Waste Heat

TL;DR

This paper introduces a novel capacitive thermoelectric converter using specific thin film dielectric materials, demonstrating potential for low-grade waste heat energy harvesting with improved efficiency over existing solutions.

Contribution

The study proposes new thin film dielectric materials for capacitive thermoelectric devices, addressing previous limitations and showing promising power output in practical microprocessor applications.

Findings

Materials exhibit sharp permittivity changes with temperature

Device can generate electricity from fluctuating thermal conditions

Potential application in waste heat recovery from electronics

Abstract

A capacitive thermoelectric device can harvest thermal energy and convert it to electrical energy by employing a temperature-dependent dielectric material whose permittivity sharply changes with temperature. Electricity can be generated by fluctuating the temperature of the capacitor. Currently, capacitive thermoelectric devices are not broadly used, which can be attributed to the low efficiency of the existing solutions, the lack of dielectric materials with suitable temperature non-linearity of the dielectric permittivity, and the complexity of modulating heat flux on the dielectric material. Here, we propose a device based on (Ba0.85Ca0.15)(Ti0.92Zr0.08)O3 and (Ba0.73Ca0.27)(Ti0.98Zr0.02)O3 thin films. The estimated power output under different operation conditions and dynamic workload of an Intel E5-2630 microprocessor show that these thin film materials are promising and can potentially be used for a capacitive thermoelectric converter.