1. Introduction
Managing over 480 buildings and nearly 450
miles of utility distribution, the IU Physical Plant
maintains the physical and natural environment of
the Bloomington campus. With over 640
employees that frequently are moving through
campus, transportation is a necessary part of the
job. The Physical Plant has a fleet of 140 trucks
that drive 1.2 million miles annually. The
~100,000 gallons of fuel consumed annually
represents a major source of pollution emissions
on campus.
This objective of this report is to consider
alternative fuel/transportation options to help
lessen the environmental impact of the Physical
Plant trucks in a safe, sustainable and cost
effective way. This report seeks to determine if
Propane, or Liquefied Petroleum Gas (LPG), is a
viable alternative fuel source for the Physical
Plant to pursue in order to decrease fuel costs and
reduce emissions.
Materials and Methods
We researched various alternative fuel sources
and environmentally friendly transportation
options. These alternatives were evaluated based
on cost, environmental impact, fuel efficiency and
time of implementation.
To find current vehicle statistics we conducted
interviews with the IU Physical Plant to inquire
about their vehicle statistics including fleet size,
fuel consumption, fuel costs, and overall
transportation costs. In the computation of fuel
costs the 2014 Indiana average fuel cost is used.
Statistics on Propane costs, efficiency and
emissions provided by the Alternative Fuels Data
Center of the US Department of Energy.
Acknowledgments
We would like to thank IU Motor Pool and Physical Plant services for
their fleet statistics. Also, we would like to thank Propane People, Inc.
for the use of their data. Finally, we would like to thank the
Alternative Fuels Data Center for providing information regarding
alternative fuel sources.
Results
Of all alternative fuel sources that we researched,
propane stands out as the most realistic fuel source
for the Physical Plant’s fleet. We analyzed
propane’s feasibility based on the following
criteria: Cost, Emissions, and Sustainability.
I. Conversion Cost
The first element of cost is the cost of conversion.
In order to run on propane engines must be
converted. The most logical conversion for the
Physical Plant would be a bi-fuel conversion which
allows for the engine to run on both LPG and
regular gasoline, which is more readily available at
gas stations. Figure 1 shows how the conversion
works with both fuel sources. Cost per truck to
convert is around $6500, however various credits
are available from propane companies to convert at
lower costs.
II. Fuel Cost
Using the fleet statistics provided by IU Physical
Plant and the AFDC, Table 1 calculates the annual
fuel costs for both LPG and gasoline using the
same amount of miles travelled and gallons
consumed.
While LPG fuel costs are significantly lower than
its fuel counterpart, there are some initial costs
associated with fueling stations. According to the
AFDC, a fueling station capable of supporting IU’s
Physical Plant fleet costs $400,000-$600,000.
Conclusions
After conducting our research and analyzing our
results we believe that propane conversion of the
IU Physical Plant truck fleet is a viable and eco-
friendly option to minimize the environmental
impact of the trucks. The $183,000 in annual fuel
savings would more than pay for the conversion
costs of 140 trucks and fueling station within the
first 5 years. The reduced emissions would help
reduce the overall footprint of a necessary service
that keeps IU running year-round.
Although propane is still derived from fossil
fuels, it is a step in the right direction in the
inevitable road to alternative fuel sources in order
to decrease fossil fuel dependency. The increased
efficiency combined with lower emissions and
fuel costs leads us to conclude that LPG
conversion of the Physical Plant fleet is a viable
alternative fuel source.
Walker Budwig-Scannell, Christiana Tsimouris, Logan Zuber
School of Public and Environmental Affairs, Indiana University, E272 Spring 2015
Literature cited
Alternative Fuels Data Center. (2015, Jan 1). Propane Basics. Retrieved from
http://www.afdc.energy.gov/fuels/propane_basics.html
Alternative Fuels Data Center. (2015, Jan 1). Propane Benefits & Considerations.
Retrieved from http://www.afdc.energy.gov/fuels/propane_benefits.html
Energy Information Administration (EIA). 2009. Energy Glossary (online). http://
www.eia.doe.gov/glossary/
The Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation
(GREET) Model, Version 1.8c. 2009. Argonne National Laboratory, Center
for Transportation Research. UChicago Argonne, LLC.
Indiana University shifting 50 jobs to temp agency. (2013, September 10). Retrieved
April 27, 2015, from http://www.theindychannel.com/news/local-news/
indiana-university-shifting-50-jobs-to-temp-agency
Propane Reduces Greenhouse Emissions: A comparative Analysis. (2009, January 1).
Retrieved April 27, 2015, from http://www.propanecouncil.org/
uploadedFiles/REP_15964 Propane Reduces GHG Emissions 2009.pdf
For further information
For further information please contact wfbudwig@indiana.edu,
ctsimour@indiana.edu or logzuber@indiana.edu. For further
information on propane, please visit www.afdc.energy.gov
III. Emissions & Safety
With high fuel efficiency and emission standards
of today’s automobile industry, it is important that
Propane emissions are lower than Gasoline in
order to make a LPG conversion viable and
within the ever increasing efficiency standards.
According to the AFDC, Propane emits:
● 60-70% less smog producing hydrocarbons
● 12% less CO2
● 20% less NOx
● 60% less CO
● 96% less Benzene and Toluene (GHGs)
Figure 2 shows the annual greenhouse gas
emissions of one Ford F-150 truck in kg CO2
equivalent per year.
Figure 2: Annual GHG emissions per unit (kg-CO2 equivalent)
Statistics provided by Propane Council
Propane reduces total GHG emissions by almost
15% versus gasoline per truck. Conversion of the
entire fleet would mean significant vehicle
emission reductions. For a fleet of 140 trucks, this
would be close to a 140,000 kg decrease in
emitted GHGs.
LPG also has an octane rating of 104, compared
to 87-92 for gasoline, which allows for a cleaner
burning of the fuel resulting in less emissions and
increased fuel efficiency.
Due to low carbon content and higher octane
resulting in a cleaner burning fuel, vehicles that
run on propane require less maintenance and
upkeep. If spilled, propane presents no risk to soil,
surface water or groundwater whereas gasoline is
a toxic and corrosive substance that can have
devastating effects on soil and water resources if a
spill is to occur.
Image courtesy of RTV6.com
Figure 1: Volvo’s Bi Fuel System
Image courtesy of Department of Energy
Propane Gasoline
MPG 10 11
$/G $1.59 $3.54
Annual Cost $189,655.20 $373,021.09
Table 1 : Annual Fuel Costs of Propane & Gasoline
Statistics provided by AFDC
Kg-CO2equivalentperunit
Propane as an Alternative Fuel Source
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
Ethanol Propane Gasoline