Comparison of Cooling Methods for a Thermoelectric Generator with Forced Convection

Abstract

A thermoelectric generator (TEG) is a clean electricity generator from a heat source, usually waste heat. However, it is not as widely utilized as other electricity generators due to low conversion efficiency from heat to electricity. One approach is a system-level net power optimization for a TEG system composed of TEGs, heat sink, and fans. In this paper, we propose airflow reuse after cooling preceding TEGs to maximize system net power. For the accurate system net power, we model the TEG system, air, and heat source with proper dimension and material characteristics, and simulate with a computational fluid dynamics program. Next, the TEG power generation and the fan power consumption are calculated in consideration of the Seebeck coefficient and internal electrical resistance varying with hot and cold side temperatures. Finally, we find the optimal number of TEGs and fan speed generating the most efficient system net power in various TEG systems. The results show that the system with a side fan with a specific number of TEGs provides a system net power up to 58.6% higher than when with a top fan. The most efficient system net power with the side fan increases up to four TEGs generating 1.907 W at 13,000 RPM.

Thermal, Energy and Exergy Analysis of Thermoelectric Generator System for Waste Heat Recovery Applications

“…A waste heat harvesting system containing an automotive exhaust pipe, copper thermal collector, single Bi 2 Te 3 -based TEG module and a liquid cooling system presented an open circuit voltage of 1.8 V at ΔT = 30 °C [25]. From Figure 5, we can see that the same U OC value was attained at ΔT = 27.5 °C, indicating an energy conversion system with similar performances under natural convective cooling of the heat sink (T C increased with only about 6 °C) at this low-temperature domain of T H , under 100 °C.…”

Review on Thermoelectric Generators (TEG) and their applications: Progress, Challenges, and future prospects

“…4(b), consists of TCs stacked vertically between the heat source and the heat sink. [30] As a result, heat flows vertically along the thermoelement arms and surfaces. This configuration is comparable to the Peltier-based refrigeration module.…”

Development, optimization, and testing of a hybrid solar panel concept with energy harvesting enhancement

“…Thermal harvesting is obtained by the use of thermal energy from the surrounding environment. The use of TEGs is one of the promising harvesting technologies, since it only requires a certain temperature difference across the thermoelectric element for producing electricity by the Seebeck effect [22]. Energy conversion efficiency of the TEG system depends on the temperature difference between the hot and cold side and the value of the figure of merit ZT of the TEG [22].…”