Effects of Design Parameters on Fuel Economy and Output Power in an Automotive Thermoelectric Generator

Martí Comamala,Eduard Massaguer,Ivan Ruiz Cózar,Albert Massaguer,Toni Pujol

doi:10.3390/en11123274

Abstract

The need for more sustainable mobility promoted research into the use of waste heat to reduce emissions and fuel consumption. As such, thermoelectric generation is a promising technique thanks to its robustness and simplicity. Automotive thermoelectric generators (ATEGs) are installed in the tailpipe and convert heat directly into electricity. Previous works on ATEGs mainly focused on extracting the maximum amount of electrical power. However, the back pressure caused by the ATEG heavily influences fuel consumption. Here, an ATEG numerical model was first validated with experimental data and then applied to investigate the effects that modifying the main ATEG design parameters had on both fuel economy and output power. The cooling flow rate and the geometrical dimensions of the heat exchanger on the hot side and the cold side of the ATEG were varied. The design that produced the maximum output power differed from that which maximized fuel economy. Back pressure was the most limiting factor in attaining fuel savings. Back pressure values lower than 5 mbar led to a < 0.2% increase in fuel consumption. In the ATEG design analyzed here, the generation of electrical output power reduced fuel consumption by a maximum of 0.5%.

Highlights

60% of the primary energy consumed in an internal combustion engine (ICE)is dissipated through the exhaust gases and the cooling system [1]
Policies toward greener and more sustainable mobility are actively promoting research programs into increasing fuel savings through heat recuperation [3]. This strategy is especially important when dealing with heavy-duty vehicles because, for long-distance transport, ICEs will continue to be the main powertrain for the mid-term future
Our objective washas to investigate the performance of our Automotive thermoelectric generators (ATEGs) the effect the ATEG

Summary

Introduction

60% of the primary energy consumed in an internal combustion engine (ICE)is dissipated through the exhaust gases and the cooling system [1]. If 6% of the exhaust heat were converted into electricity, fuel consumption would be reduced by 10% [2]. Policies toward greener and more sustainable mobility are actively promoting research programs into increasing fuel savings through heat recuperation [3]. This strategy is especially important when dealing with heavy-duty vehicles because, for long-distance transport, ICEs will continue to be the main powertrain for the mid-term future. Among different waste heat recovery techniques, thermoelectric generators (TEGs) have many advantages: light weight, simple structure, high reliability, and quiet operation. The core of a TEG is composed of thermoelectric modules (TEMs) that directly convert heat flow rate into electric power

Objectives

Results

Conclusion