Int. J. of Thermal & Environmental Engineering
Volume 16, No. 1 (2018) 51-58
*
Adriana Vargas-Martínez. Tel.: +5218119173592
E-mail: adriana.vargas@udem.edu
© 2018 International Association for Sharing Knowledge and Sustainability
DOI: 10.5383/ijtee.16.01.007
51
Study of an Electric Energy Generation System from
Exhaust Waste Recovery from an Internal Combustion Engine
Jorge de-J. Lozoya-Santos, Jonathan Rivas Torres, Adán Sáenz Herrera, Julio C. Salinas-Maldonado,
Eduardo Mariscal Hay, Adriana Vargas-Martínez
*
Universidad de Monterrey, San Pedro Garza García, México
Abstract
A conventional car engine uses at best about one-third of the fuel combustion energy, while the rest of the energy is lost
in friction and most in heat. In the face of the new emission regulations proposed by the government due to the high levels
of pollution, and with the aim of achieving cleaner and more efficient transportation, vehicle exhaust gas recovery is being
researched in the last years. It is of interest for the automotive industry to recover this wasted energy, thus increasing
engine efficiency, reducing fuel consumption and pollution. One way to achieve both objectives is the conversion of engine
waste heat to a more useful form of energy, either mechanical or electrical. This paper study a system prototype based on
Brayton´s thermodynamic cycle driving an Electrical Generator to recover energy from the exhaust gases from a
commercial internal combustion engine.
Keywords: Exhaust Gas Recovery, Turbocharging, Brayton Cycle Efficiency.
1. Introduction
In recent years, OEM’s have been put to a big challenge to
further reduce the CO2 emission from vehicles [1]. Along with
hybridization, improving efficiency and lowering fuel
consumption from vehicles equipped with internal combustion
engine (ICE) is the main way to achieve it. Since the early
beginnings of ICE, constructors have been aware that a big
portion of energy is wasted by throwing high enthalpy exhaust
gases to atmosphere [2], from a small percentage that could be
mostly useful to be used to improve powertrain efficiency. In a
typical energy flow path of an internal combustion engine, only
25% of the fuel combustion is utilized for vehicle operation,
whereas about 70% of the total fuel energy dissipates to the
environment as heat loss primarily through the vehicle exhaust
system and radiator [3]. Heat available in the exhaust gas of an
engine can be an important heat source [4].
2. Background
2.1. Waste Heat Recovery
Many researchers recognize that Waste Heat Recovery from
engine exhaust has the potential to decrease fuel consumption
without increasing emissions, and recent technological
advancements have made these systems viable and cost effective
[5], [6]. A waste heat recovery system has the potential to
convert some of this waste heat into electricity and consequently
reduce the fuel consumption of the car by driving the alternator
with exhaust gas energy, instead of doing it with the mechanical
output of the engine [7].
Given the importance of increasing energy conversion
efficiency for reducing both the fuel consumption and emissions
of engine, scientists and engineers have done lots of successful
research aimed to improve engine thermal efficiency, including
supercharge, lean mixture combustion, etc. However, in all the
energy saving technologies studied, engine exhaust heat
recovery is one of the most effective [7].