Compact automotive thermoelectric generator with embedded heat pipes for thermal control

Abstract

Currently, the automotive industry faces challenges to implement solutions that provide reductions in energy consumption, pollutants and greenhouse-gas (GHG) emissions. Exhaust heat recovery employing Thermoelectric generators (TEGs) enables the direct conversion of heat into electric energy without moving parts and little to no maintenance. On-board electrical production is especially useful given the growing electrification trend of road vehicles. The present work assesses the performance of a novel temperature-controlled thermoelectric generator (TCTG) concept in a light duty vehicle and its impact on fuel economy and GHG emissions under realistic driving conditions. The novel exhaust heat exchanger (HE) concept consists of corrugated pipes embedded in a cast aluminium matrix along with variable conductance heat pipes (VCHPs) acting as spreaders of excess heat along the longitudinal direction. This concept seems to have a quite good potential for highly variable thermal load applications, as it is able to avoid overheating by spreading heat instead of wasting it through bypass systems. Furthermore, when compared to previous concepts by the group, it does not need gravity assistance and has a form factor similar to conventional generators. It also appears to be capable of delivering a breakthrough electric output for TEG systems in such light vehicles, with as much as 572 W and 1538 W of average and maximum electric powers during a driving cycle, respectively, and showing a quite promising reduction of 5.4% in fuel consumption and CO2 emissions.

Current and Future Trend Opportunities of Thermoelectric Generator Applications in Waste Heat Recovery

“…The electrical energy supplies are especially helpful to give the producing electrification trend in transport moving vehicles. A performance of a temperature-controlled TEG with embedded heat pipes concept in a light duty vehicle was tested in [69]. It showed that the greenhouse gases emission was reduced.…”

Complex Fluid Flow in Microchannels and Heat Pipes with Enhanced Surfaces for Advanced Heat Conversion and Recovery Systems

“…The concept of heat recovery systems is emerging in the design of internal combustion engines (ICE), particularly for heavy-duty vehicles, where different waste heat recovery techniques have been explored [1][2][3][4][5]. Thermoelectric generators (TEGs) are also clean, robust, modular, and a low-maintenance to maintenance-free solution if carefully designed, allowing for considerable heat recovery from internal combustion engines, namely from exhaust gases [5,6].…”

Research on Module Layout and Module Coverage of an Automobile Exhaust Thermoelectric Power Generation System

“…Marvão et al [30] studied three heat exchangers with plain fins, offset strip fins, and triangular fins and discovered that thinner fins can better increase the net power. Pacheco et al [31] artificially enhanced heat transfer by embedding a heat pipe in the channel, which caused a large pressure drop due to the small channel size. Fernández-Yañez et al [32] studied four internal structures of heat exchangers, including one type of long fins, two types of short fins, and one type of channel-arranged fins.…”