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Comparative life cycle assessment of sport utility vehicles with different fuel options

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Purpose Sport utility vehicles typically have lower fuel economy due to their high curb weights and payload capacities as well as their potential to cause serious environmental impacts. In light of this fact, a life cycle assessment is carried out in this study to assess their cradle-to-grave environmental impacts for life cycle phases ranging from manufacturing to end-of-life recycling. Methods A hybrid economic input-output life cycle assessment (EIO-LCA) method is used in this research paper to estimate the environmental impacts (greenhouse gas emissions, energy consumption, and water withdrawal) of sport utility vehicles. This life cycle assessment is also supplemented with a sensitivity analysis, using a Monte Carlo simulation to estimate the possible ranges for total mileage of operation and fuel economy, and to account for the sensitivity of the EIO-LCA output. Results and discussion The operation phase is the major contributor to the overall life cycle impact of sport utility vehicles in each fuel/power category. Furthermore, among the selected vehicles in this study, the battery electric vehicle has the lowest greenhouse gas emissions (77.2 tonnes) and the lowest energy consumption (1046.8 GJ) even though the environmental impact indicators for the battery manufacturing process are significantly large. The plug-in hybrid vehicle, on the other hand, demonstrates an optimal performance between energy use and water withdrawal (1172.9 GJ of energy consumption and 1370 kgal of water withdrawal). In addition, all of the fuel-powered vehicles demonstrated similar environmental performances in terms of greenhouse gas emissions, which ranged between 100 and 110 tonnes, but the hydrogen fuel cell vehicle had a significantly large water withdrawal (2253.2 kgal). Conclusions Since the majority of the overall impact stems from the operation of the vehicle in question, their complete elimination of tailpipe emissions and their high energy efficiency levels make battery electric vehicles a viable green option for sport utility vehicles. However, there are certain uncertainties beyond the scope of this study that can be considered in future studies to improve upon this assessment, including (but not limited to) regional differences in source of electricity generation and socio-economic impacts.
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ROADWAYS AND INFRASTRUCTURE
Comparative life cycle assessment of sport utility vehicles
with different fuel options
Enes Karaaslan
1
&Yang Zhao
1
&Omer Tatari
1
Received: 28 April 2016 /Accepted: 30 March 2017 /Published online: 10 April 2017
#Springer-Verlag Berlin Heidelberg 2017
Abstract
Purpose Sport utility vehicles typically have lower fuel econ-
omy due to their high curb weights and payload capacities as
well as their potential to cause serious environmental impacts.
In light of this fact, a life cycle assessment is carried out in this
study to assess their cradle-to-grave environmental impacts
for life cycle phases ranging from manufacturing to end-of-
life recycling.
Methods A hybrid economic input-output life cycle assess-
ment (EIO-LCA) method is used in this research paper to
estimate the environmental impacts (greenhouse gas emis-
sions, energy consumption, and water withdrawal) of sport
utility vehicles. This life cycle assessment is also supplement-
ed with a sensitivity analysis, using a Monte Carlo simulation
to estimate the possible ranges for total mileage of operation
and fuel economy, and to account for the sensitivity of the
EIO-LCA output.
Results and discussion The operation phase is the major con-
tributor to the overall life cycle impact of sport utility vehicles
in each fuel/power category. Furthermore, among the selected
vehicles in this study, the battery electric vehicle has the low-
est greenhouse gas emissions (77.2 tonnes) and the lowest
energy consumption (1046.8 GJ) even though the environ-
mental impact indicators for the battery manufacturing pro-
cess are significantly large. The plug-in hybrid vehicle, on the
other hand, demonstrates an optimal performance between
energy use and water withdrawal (1172.9 GJ of energy
consumption and 1370 kgal of water withdrawal). In addition,
all of the fuel-powered vehicles demonstrated similar environ-
mental performances in terms of greenhouse gas emissions,
which ranged between 100 and 110 tonnes, but the hydrogen
fuel cell vehicle had a significantly large water withdrawal
(2253.2 kgal).
Conclusions Since the majority of the overall impact stems
from the operation of the vehicle in question, their complete
elimination of tailpipe emissions and their high energy effi-
ciency levels make battery electric vehicles a viable green
option for sport utility vehicles. However, there are certain
uncertainties beyond the scope of this study that can be con-
sidered in future studies to improve upon this assessment,
including (but not limited to) regional differences in source
of electricity generation and socio-economic impacts.
Keywords Battery electric SUV .Hybrid EIO-LCA .
Hydrogen fuel stack SUV .Light-duty trucks .Sensitivity
analysis .Sport utility vehicle
1 Introduction
According to the US Environmental Protection Agencysre-
port on the 2014 greenhouse gas inventories for each indus-
trial sector (U.S. EPA 2016), road transportation alone is re-
sponsible for approximately 20% of the total greenhouse gas
emissions on earth, and light-duty trucks (sport utility vehi-
cles, minivans, and pickup trucks) account for 1% of global
energy use and greenhouse gas (GHG) emissions. As a type of
light truck, sport utility vehicles (SUVs) have recently gained
a great deal of popularity and currently constitute a significant
percentage of the number of personal passenger cars currently
in use in the USA. The term sport utility vehicle (SUV) is used
to describe a large vehicle designed to be used in rugged
Responsible editor: Wulf-Peter Schmidt
*Omer Tatari
tatari@ucf.edu
1
Department of Civil, Environmental, and Construction Engineering,
University of Central Florida, Orlando, FL 32816, USA
Int J Life Cycle Assess (2018) 23:333347
DOI 10.1007/s11367-017-1315-x
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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