Heat storage thermoelectric generator as an electrical power source for wireless Iot sensing systems

Abstract

This article demonstrates a new approach using a thermoelectric generator (TEG), which converts thermal energy from ambient temperature fluctuations into electricity for the power source of portable devices. Using TEGs with heat storage material on one side of the TEG, a temperature difference can be created at both sides of the TEG from ambient temperature variations. In this work, the electric power generation and its storage to a capacitor are evaluated for the TEG-heat storage device. Two kinds of TEGs (#1 and #2) with different sizes have been evaluated. Maximum output power densities of TEGs #1 and #2 are 0.27 and 0.45 mW/cm 2 at temperature difference ΔT = 7 C, respectively. The electric power from the TEG can be stored in a capacitor via a DC-DC converter. The temperature difference dependences of the electronic conversion efficiency for the DC-DC booster are evaluated for both TEGs. A charge stored in the capacitor is 113 μAh under ΔT = 3 C. The maximum output power and the storable energy in the capacitor are 30 μW and 500 mJ, respectively, under ambient temperature fluctuations in near room temperature. The investigation in this work could possibly lead to high potential for battery-free wireless sensing systems. K E Y W O R D Sambient temperature fluctuations, phase-change material, thermoelectric generator, wireless internet of things sensing system

Low-power Renewable Possibilities for Geothermal IoT Monitoring Systems

“…In recent years, many researchers published their work in this field, due to the advantages of using geothermal energy or other heat sources as a source of power for supplying IoT devices [1], [3]- [15]. It is necessary to first consider the possibilities of available geothermal energy and choose the appropriate procedure and IoT equipment accordingly.…”

“…It is possible to use a geothermal or heat-based energy generator, which does not depend on the sun, or weather, due to source discontinuities. The occurrence of usable water resources is also limited [3].…”

“…There is no problem with the discontinuity of the geothermal heat source and ideally, it can last forever. The amount of harvested energy strongly depends on the performance of thermoelectric materials and the source of heat [3], [4]. Another big advantage of geothermal energy is energy generation without the need for moving parts such as turbines, which eliminates maintenance and extra cost [5].…”

Thermoelectric properties of La1.96Sr0.04CuO4 for energy harvesting and storage applications

“…Furthermore, the energy harvested from waste heat can also be stored by integrating the thermoelectric generators (TEG) with energy storage devices viz. battery, capacitor, etc 2 . In order to address the requirement of power at peak time, L. Talluri et al 3 have suggested a system based on thermo‐electric energy storage (TEES) and analysed the different parameters affecting the cost of power produced.…”

“…battery, capacitor, etc. 2 In order to address the requirement of power at peak time, L. Talluri et al 3 have suggested a system based on thermo-electric energy storage (TEES) and analysed the different parameters affecting the cost of power produced. J. Wang et al 4 developed a thermoelectric-based system to convert waste heat into electric energy.…”