EPA-AA-TEB-EF-91-x
The MOBILE4 Fuel Consumption Model
April 1991
Mark A. Wolcott
U.S. Environmental Protection Agency
Ann Arbor, Michigan
Dennis F. Kahlbaum
Computer Sciences Corporation
Ann Arbor, Michigan
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NOTICE
This document has not been peer and administratively reviewed within EPA and is for internal
Agency use/distribution only.
NOTICE
Technical Reports do not necessarily represent final EPA decisions or positions. They are intended
to present technical analysis of issues using data which are currently available. The purpose in the
release of such reports is to facilitate the exchange of technical information and to inform the public
of technical developments that may form the basis for a final EPA decision, position or regulatory
action.
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Table of Contents
Page
I. Background 1
II. Inputs 2
A. Vehicle Stock 2
B. Registration Distributions 9
C. Vehicle Miles Traveled 10
D. Diesel Market Penetration 11
E. Fuel Economy 12
F. Total Emissions 13
III. Outputs 14
A. Fleet Fuel Consumption 15
B. Fleet Vehicle Miles Traveled 15
C. RoadMPG 15
D. Vehicle Registrations & Total Emissions 21
IV. Sensitivity 21
References R-l
Appendixes
A. Model Input-Tables A-l
B. Model Input-Figures B-l
C. Model Input-Prompts C-l
-i-
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The MOBILE4 Fuel Consumption Model
I. Background
The MOBELE4 Fuel Consumption (M4FC) model was developed to estimate gasoline and
diesel fuel used by motor vehicles. It is based on the MOBILE4 mobile source emissions model1
and predicts the amount of gasoline, diesel and alternative* fuels consumed for each of seven
vehicle classes.
M4FC is, in several respects, different from its predecessor, the MOBILES Fuel
Consumption model (M3FC). Both the registration and vehicle miles traveled distributions have
been updated to MOBILE4 levels. Separate city and highway fuel efficiencies have been included
and allowance is made for the gradual shift to urban driving. Also, the model now directly reads
output from the MOBILE4 emissions model and estimates tons of hydrocarbons (HC), carbon
monoxide (CO), oxides of nitrogen (NOX) and carbon dioxide (CO2).
Several different fuel consumption models have been developed over the years.2-3'4'5-6
None, however, is consistent with MOBILE4. Since MOBILE4 is the emission model used to
evaluate present and potential motor vehicle regulations, it is desirable to estimate the benefits from
those regulations with a fuel consumption model for which the underlying assumptions are the
same.
While the primary concern behind the Agency's regulations is the public's health and
welfare, these quantities are difficult to measure. Tons of pollutants eliminated and ambient
concentrations reduced tend to be easier to estimate. In the past, MOBILE4, in combination with
Rollback and EKMA,7 were sufficient to estimate the surrogates to health and welfare.
MOBILE4 itself estimates grams of carbon monoxide, hydrocarbons and oxides of
nitrogen emitted for each mile a vehicle travels. In general, these pollution estimates are not
particularly sensitive to fuel economy. This is particularly true with respect to light duty vehicles
(LDV) and light duty trucks (LDT).
Refueling emission losses as calculated in MOBILE4,** however, depend on total vehicle
miles traveled (VMT) and fuel economy (mpg), as well as many other factors. Further, the
benefits from controlling fuel volatility are, in part, a function of the total volume of gasoline
consumed. A fuel consumption model based on MOBILE4 lends itself to calculating the fuel
consumption benefits of controlling fuel volatility more readily than MOBILE4 used by itself.
The principle of computing fuel consumption is basically simple. Total fuel consumed is
a function of the total number of vehicles, the number of miles each vehicle travels, and each
vehicle's fuel economy. Therefore, the more vehicles there are and the more miles they travel, the
more fuel they will consume. On the other hand, the greater the fuel economy these vehicles
obtain, the less fuel they will consume.
Since the inputs for the alternative fuels sections of the model are undergoing internal EPA
review for the Alternative Motor Fuels report, the scenarios included in this report assume all
vehicles are powered by conventional fuels.
Actual refueling losses depend upon the number of refueling events.
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In the sections that follow a detailed description of each model input is presented.
Included are registrations, VMT, and mpg for each vehicle class. This discussion of inputs is
followed by a presentation of the model's outputs. These outputs include fleet fuel consumption
and vehicle miles traveled, road fuel economy, vehicle registrations and total emissions. Also
included is a sensitivity analysis that shows how gasoline consumption, vehicle miles traveled and
carbon dioxide emissions vary as one changes certain critical input assumptions. Finally, the
appendicies display the input data in both table and graphical form as well as explain the prompts
proffered by the model during its execution.
II. Inputs
As noted in the introduction, the principle of computing fuel consumption is basically
simple. Total fuel consumed is a function of the total number of vehicles, the number of miles
each vehicle travels and each vehicle's fuel economy. In mathematical notation it is represented by
the following equation:
Fuel Consumption=[Number of Vehicles] [VMT]/[Fuel Economy]
However, this equation assumes that all vehicles have the same age, VMT, and fuel
economy. In reality, the vehicles operating in any given calendar year are a mixture of model
years. Different model years have different fuel economy characteristics and vehicles of different
ages have different travel characteristics. Also, since diesel fuel has a higher heating value than
gasoline fuel, fuel type is a factor in fuel consumption estimates. Thus, a more accurate equation is
Fuel Consumption(i,j,k)=[Number of Vehicles(i,j,k)]
[VMT(i jJOMFuel Economy(ijjk)]
where i=age, j=fuel type, and k=vehicle class. This is the form of the equation used by the M4FC
model. In M4FC age (i) ranges from 1 to 30 years; fuel type (j) represents either gasoline, diesel
or one of several alternative fuels and vehicle class (k) represents one of seven vehicle classes.
Further, since M4FC is capable of computing fuel consumption estimates from 1982 to
2020 and, since at least a few vehicles are assumed to remain operational for up to 30 years, most
input data must be available from 1953 through 2020. Operationally this has often meant that the
time series of a variable remains constant at one level for some very early years and, in most cases,
remains constant at a different level for all years beyond the year 2000.
II.A. Vehicle Stock
The fkst element of the fuel consumption equation is referred to as the vehicle stock, the
total number of vehicles operating in a given calendar year. Vehicle stock estimates are required
for each vehicle class for every projection year.
The initial step of estimating vehicle stock is to obtain historical total stock estimates.
Historical estimates are available principally from two sources, the R.L. Polk Company8 and the
Federal Highway Administration (FHwA).9
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Although the truck stock estimates from these two sources are similar for all years, car
registrations differ markedly. Figures 1-2 show the vehicle stock estimates from these two
sources.
Figure 1
Car Registrations
B
o
a
s
c
o
00
u
02
150
140-
130-
120-
110 -
100-
90-;
80-
70-
60-
50 ;
40
30 -
20 :
10 :
0
Polk Cars
FHwACars
1950 1955 1960 1965 1970 1975 1980 1985 1990
Year
Figure2
Truck Registrations
150
140-
130-
120-
110 -
100-
90:
80-
70-
60 -
50-;
40-
30:
20-
10 :
0
Polk Trucks
FHwA Trucks
1950 1955 1960 1965 1970 1975 1980 1985 1990
Year
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According to Oak Ridge National Laboratories (ORNL),10 there are several reasons for
these differences:
1. The FHwA count includes all vehicles that have been registered throughout
the calendar year. Therefore, their number includes vehicles retired during
the year and double counts vehicles that have been registered twice in either
different or possibly the same states. The Polk count only includes vehicles
that are registered on July 1, thus factoring in scrappage, to some degree,
and avoiding double counting.
2. Beginning with the 1980 estimate, Polk counts vans as light trucks, rather
than passenger cars. The FHwA count includes vans as passenger cars or
trucks, depending on individual state classifications.
It is for these reasons that the Polk estimates appear to be a better indicator of the average
automobile stock during a calendar year than are the FHwA estimates.
While these same reasons apply to estimates of truck registrations, the two groups' truck
estimates are closer, since a truck is less likely to be re-registered within a given calendar year.
The M4FC model uses the Polk values as the basis for its historic car and truck vehicle stocks. It
also uses Polk values to project the future stock of cars and trucks.
Figure 3 shows that the average number of passenger vehicles per person steadily
increased between 1950 and 1979. In 1980 Polk classified 1,310,918 passenger cars as light
trucks.11
0.0
Figure 3
Cars per Person
Cars/Person = - 15.433 + Year*8.0359e-3
= 0.994
1950 1960 1970
i
1980
1990 2000 2010 2020
Year
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Classification of light vehicles as cars or trucks has always been difficult. To a certain
extent, some have always used light trucks in the same way that they use passenger cars; i.e. as
their principal means of personal transportation. This is clearly evident in the use of light pickup
trucks and mini-vans today. Since the frequency of this type of truck use may have begun to
increase with the introduction of emission standards as early as 1969, the 1960-1969 trends in
vehicle ownership are used in the projection methodology described below.
To allow for the shift from light duty vehicles to light duty trucks while at the same time
maintaining the historic increase in the number of passenger-type vehicles per person, the model
uses the product of expected population12 and the 1960-1969 trend in passenger vehicles per
person to calculate both the historic and the projected stock of cars and light trucks used as cars:
Historic Split (Pre-1990) - Polk registrations are used directly to estimate the total
stock of light duty vehicles while the difference between the estimated passenger
car stock based on the 1960-1969 trend in the number of passenger vehicles per
person and Polk light duty vehicle registrations is used to estimate the number of
light duty trucks that are used as light duty vehicles.
Future Split (1990+) - The 1960-1969 trend in the number of passenger vehicles
per person is also used to estimate the future stock of light duty vehicles and light
duty trucks that are used as light duty vehicles.* The model splits the projected
total of passenger-type vehicles into its component parts (LDVs and LDTls that
operate like LDVs) by assuming that the sales fraction of personal vehicles that are
trucks remains constant at 1990 levels for all years after 1990.
The sales fraction of personal vehicles that are trucks is calculated in the following
manner. First, the 29.6 percent of the light duty fleet that are light duty trucks in
199Q13 is adjusted downward to 27.0 percent to account for the increase in freight
carried by trucks between 1969 and 1990.n Second, the difference between that
value and the imputed 1969 fraction of the light duty fleet that are light trucks is
. calculated. See Figures 4-5.
The total stock of commercial trucks** is projected in a similar fashion.
* Light duty trucks that are used as light duty vehicles are assumed to travel and be scrapped at
the same rate as light duty vehicles. They are also assumed to reflect the diesel penetration
rate of cars.
** Commercial trucks are defined for the purposes of this report as Class 1-8B trucks less those
Class 1 and 2 trucks used as passenger vehicles.
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§
u.
I
5
' Figure 4
LDT Market Fraction
0.4
0.3-
0.2-
0.1-
0.0
Market Fraction = - 15.572 + Year*7.9735e-3 R*2 = 0.683
1969 1972 1975 1978 1981 1984 1987 1990
Year
8
26
24 -
22
20 -
18 -
16 -
14 -
12 -
10-
8-
6-
4-
1-
0
Figure 5
Percent of Total Freight by Truck
Freight = - 179.81 + Year*0.10273 R*2 = 0.500
1960 1965 1970 1975 1980 1985 1990
Year
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In the case of commercial trucks, account is also taken of the increase in the proportion of
freight that is carried by trucks. Figure 5 shows that, since 1960, trucks have increased their share
of freight from 21.7% to 25.2%. The 1960-1969 trend in commercial truck stock shown in Figure
6 is expected to continue as the national economy continues to become more of a service economy
and as all industries try to reduce their inventory costs through just-in-time ordering techniques.
Figure 7 shows the number of commercial trucks per person estimated by this methodology.
X
8
ex
H
Figure 6
Commercial Trucks/(US Population * Freight Index)
0.04
1960
1965
1970
1990
1975 1980 1985
Year
Trucks/(Population*Index) = - 4.2714 + Year*2.2003e-3 RA2 = 0.900
§
5
0.8
0.7-
0.6-
0.5-
0.4-
0.3-
0.2-
0.1-
0.0
Figure 7
Estimated Commercial Trucks per Person
1950 1955 1960 1965 1970 1975 1980 1985 1990
Year
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The total stock of commercial trucks is distributed to the various weight classes by
projected sales according to the following recursive procedure:
1. Obtain the 1982* Truck Information and Use Survey (TIUS) class-specific
truck stocks.14-15
2. Scrap a constant 5.7 percent** of vehicles in each weight class.
3. Add 1983 Class 1 sales from MVMA Facts and Figures11 to obtain a
preliminary Class 1 stock estimate for 1983.
4. Subtract 1983 MVMA Class 1 sales from 1983 LOT (Class 1+2A) sales
from EPA's Fuel Economy Trends report13 to obtain 1983 Class 2A sales
estimates. Add these to the 2A stock estimate to obtain the preliminary 1983
stock estimate.
5. Subtract the Trends report LOT 1983 sales from the MVMA Class 1+2 sales
to obtain Class 2B sales. Add these to the 2B stock estimate to obtain the
preliminary 1983 stock estimate.
6. Add Classes 3-8B sales from the Heavy-Duty Vehicle Emission Conversion
Factors II report17 to obtain the preliminary 1983 stock estimates for these
classes.
7. After the scrapped vehicles are removed from the fleet and sales are added,
the number of light duty trucks that are used as passenger cars is subtracted
from Class 1 trucks and the resulting total number of commercial trucks is
compared to the projected Polk figures. These are then renormalized by
weight class to reflect not only the Polk figures but also follow the vehicle
stock trends assumed for MOBILE4.
8. This process is repeated for each subsequent year based on the following
sales assumptions:
0 Class 1, 2A and 2B sales estimates are calculated from
MVMA Facts and Figures11 and EPA's Fuel Economy
Trends13 through 1989. The 1982-1989 average class-
specific sales are grown at a two percent per year rate
thereafter in keeping with the assumption regarding
Classes 5-6 sales used in EPA's Conversion Factor
report.17
* These are the most recent available data. An updated survey is in the process of being
completed by the U.S. Department of Commerce.
** This scrappage rate is an average of the 1950 to 1989 calendar year estimates published in
Ward's Automotive Yearbook16 (Actual sales and scrappage rates are used for 1983-1989.
The constant 5.7 percent scrappage rate is used for calendar years 1990 and later.)
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Classes 3-8B sales estimates from the Conversion Factor
report17 are used for the 1982-2000 period. Thereafter, a
two percent per year growth rate is also assumed for these
classes.
Historical (1950-1988) stocks of both public and school buses were derived from FHwA
Highway Statistics9 Table MV-10. Future stocks were estimated by applying the trend in the
number of buses per capita to the expected population.12 See Figure 8.
Figure 8
Buses per Person
0.003
0.002-
0.001-
0.000
School/Person = - 7.1447e-2 + Year*3.7011e-5 RA2 = 0.983
Public/Person = 4.6511e-3 - Year*2.1203e-6 RA2 = 0.008
Public
School
11 !! I I I I I 1 I I 1 1 1 I I . I 111.,. . .
1950 1955 1960 1965 1970 1975 1980 1985 1990
Year
II.B. Registration Distributions
In any calendar year, the total vehicle stock consists of vehicles of different vintages.
Since each vintage has its own unique blend of fuel economy and VMT, it is necessary to know
how many vehicles there are of each age. The MOBILE4 registration distributions form the basis
upon which these estimates are made for M4FC. (For an explanation of these distributions, see
"MOBILE4 Travel Characteristics".18)
However, before the MOBILE4 distributions can be used in the fuel consumption model,
certain modifications are needed. The MOBILE4 registration estimates are assumed to be as of
July 1 of each year, before the first model year's sales are complete. In addition, all vehicles older.
than 19 years of age are added together and placed in the 20+ age group. To adjust for these
differences, the original MOBILE4 registration equations, covering ages 2 to 19 years, were
extrapolated forward to a full first year and extended backward to 30 years of age. The resulting
series was then renormalized so that the total adds up to 100 percent.
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Since there are eight vehicle class-fuel type combinations in MOBILE4 and many more
than that in the M4FC model, the mapping scheme shown in Table 1 is used:
Table 1
Registration Distributions
M4FC MOBILE4 Registration
Vehicle Distribution Used
Class Gas Diesel
LDV LDV LDV
LDT1 LDT LDT
LDT2 LDT LDT
Class 2B HDGV HDDV
Class 3 HDGV HDDV
Class 4 HDGV HDDV
Class 5 HDGV HDDV
Class 6 HDGV HDDV
Class 7 HDGV HDDV
Class 8A HDGV HDDV
Class 8B HDGV HDDV
School Buses
Public Buses
Off-Highway
To actually obtain the number of vehicles of a certain age, the calendar year dependent
vehicle stock is multiplied by the fraction of vehicles at that age:
Number of Vehicles (age)=[Vehicle Stock]
[Registration Distribution(age)]
where age ranges from 1 to 30.
With the exception of buses and off-highway vehicles,* this methodology is used for
each year and vehicle class analyzed by the model. The registration data for buses and off-
highway vehicles are calendar year dependent rather than age dependent and so do not require
registration distributions in their calculations.
II.C. Vehicle Miles Traveled
Total vehicle miles traveled per year is simply the product of the average number of miles
each vehicle travels and the total number of vehicles in the fleet. The number of miles traveled per
vehicle is dependent on age as well as class. M4FC uses the VMT age curves found in the
MOBILE4 model and shown in Table 2 below. (For further detail on these curves, see
"MOBILE4 Travel Characteristics".18) The mapping scheme is nearly the same as that used for
registration distributions.
10
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Table 2
Mileage Accumulation Distributions
M4FC MOBILE4 Mileage Accumulation
Vehicle Distribution Used
Class Gas Diesel
LDV LDGV LDDV
LDT1 LDGT1 LDDT
LDT2 LDGT2 LDDT
Class 2B HDGV LDGT2
Class 3 HDGV LHDDV
Class 4 HDGV LHDDV
Class 5 HDGV LHDDV
Class 6 HDGV MHDDV
Class 7 HDGV MHDDV
Class 8A HDGV MHDDV
Class 8B HDGV HHDDV
This scheme is fairly straightforward except for Class 2B. The LDGT2 distribution was
assigned to Class 2B because this class behaves more like the LDGT2 class than like any of the
other heavy duty classes.
For all distributions it is assumed that vehicles over 20 years of age travel annually the
same distance as age 20 vehicles.
II.D. Diesel Market Penetration
Each model year a certain number of gas and diesel vehicles are produced. The fraction
of diesel vehicles compared to the total number of vehicles produced for a given class is referred to
as the diesel market penetration rate. In M4FC, these rates are used to estimate the number of gas
and diesel vehicles operating in each model year. This is accomplished by using the following
formulas:
Number of Diesel Vehicles(year)=[Number of Vehicles(year)]
[Diesel Penetration(year)]
Number of Gas Vehicles(year)=[Number of Vehicles(year)]
[1-Diesel Penetration(year)]
The diesel penetration rates used in M4FC are the same as those in MOBILE4.1
The treatment of these vehicle categories is slightly different than the others. Only total VMT
and fleet mpg are available for buses. Therefore, individual model year distributions are not
included in the model.
11
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At present, the future dieselization of the LDV and LDT fleets is uncertain. To allow for
this uncertainty, the model has a provision to place a maximum limit on the LDV and LDT diesel
penetration rates after 1988. This rate can be set in the range of 0 to 5 percent for LDVs and from
0 to 15 percent for LDTs.* Operationally, this means that the diesel penetration rate assumed by
the MOBILE4 emissions model is replaced by the limit imposed by this option beginning in the
year specified.
^
II.E. Fuel Economy
Fuel economy estimates are derived from a variety of sources. An internal EPA
memorandum "Fuel Consumption Model Inputs"19 provides new vehicle fleet road mpg for LDVs
and LDTs for the 1962-1974 period.** EPA's Fuel Economy Trends report13 provides new
vehicle test mpg for LDVs and LDTs for the 1975-1990 period. Absent any changes in the
Corporate Average Fuel Economy (CAFE) standards, test fuel economy is assumed to remain
constant at 1990 levels for all projection years.
Since these estimates are not fuel type specific, a diesel advantage factor is included to
indicate the degree to which diesel fueled vehicles obtain a fuel economy greater than their gasoline
counterparts. These two estimates, along with the model year specific diesel penetration rates for
each model year, are combined to estimate separate gasoline and diesel fuel economies. See
Appendix A. The two equations used are:
Gas mpg=[Fleet mpg]«([l-Diesel Penetration]
+[Diesel Penetration]/[Diesel Advantage Factor])
Diesel mpg=[Gas mpg]»[Diesel Advantage Factor]
Test fuel economy is discounted to road fuel economy by applying a constant 0.90
multiplicative factor to city driving and a constant 0.78 factor to highway driving.20*** These are
weighted together using the calendar-year-specific proportion of urban driving listed in Highway
Statistics9 to arrive at a road fuel economy. See Figure 9. Actual values were used for the period
1968-1988. Beyond 1988, the 1968-1988 trend was linearly extrapolated. This gradual increase
in the proportion of all driving that is urban is referred to in this report as "urbanization".
* The 1988 diesel penetration rate for LDVs and LDTs was 0.0% and 0.2%, respectively.
** MPG values prior to 1962 are assumed to be the same as those in 1962.
*** No adjustment was made in this analysis for the CAFE allowance associated with changes in
EPA's test procedure. Historically, this has amounted to between 0.0010 and
0.0050.21'22-23-24-25
12
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e
o
a
&
70
60 -
50-
40 -
30-
20 -
10-
0
1965
Figure 9
Urban VMT Percentage
1970 1975 1980
Year
1985
1990
EPA's Conversion Factor report17 provided separate gas and diesel road mpg values for
1962 to 2000 model years for class 2B-8B trucks. As with the light duty classes, mpg values prior
to 1962 were assigned the 1962 values.
II.F. Total Emissions
Total highway vehicle hydrocarbon, carbon monoxide and oxides of nitrogen emissions
are estimated as simply a product of fleet VMT and MOBILE41 emission factors. Carbon dioxide
emissions are calculated by using a carbon balance method.26
The carbon balance method relies on the assumption that mass, in the form of carbon, is
conserved in the combustion process. Therefore, given the amount of carbon in the fuel, one can
determine the amount of CO2 released into the air as the difference between the total amount of
carbon in the fuel and the amounts of hydrocarbon and carbon monoxide released in the exhaust
and through evaporation.
Three sets of MOBILE4 emissions model input assumptions were used to calculate total
emissions:
Projection
Year
1975-1988
1989-1991
1992+
I/M
Program
No I/M
Standard I/M
Standard I/M
Gasoline
RVP
11.5 psi
10.5 psi
9.0 psi
13
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All other MOBILE4 inputs were left at their default settings, including temperature (75°F),
speed (19.6 mph) and vehicle operating condition (20.6% VMT in cold start mode, 27.3% VMT in
hot start mode and 52.1% VMT in stabilized operating mode). Thus, the HC, CO and NOX
inventories shown will not reflect the full range of input conditions used to model highway mobile
source emissions by more refined methods.27.28,29,30
Nevertheless, their inclusion in this report allows the model to project CO2 emissions
through the following two carbon balance equations:
Gasoline: CO2 = 2421 - mpg (0.866 HC + 0.429 CO)
0.273 mpg
Diesel: CO2 = 2778 - mpg (0.866 HC + 0.429 CO)
0.273 mpg
The CO2 emissions inventory is considerably less sensitive than the HC, CO or NOX
inventories to variations in MOBILE4 input assumptions.
III. Outputs
The M4FC model outputs fuel consumption estimates for seven different vehicle classes
and seven different fuel types. These classes and their composition are summarized in Tables 3-4.
Table 3
Vehicle Classes
Designation Description
LDV Light Duty Vehicles (passenger cars)
LDT Light Duty Trucks , 0-8500 Ibs GVW
Classes 2B-5 Light Heavy Duty Trucks, 8501-19500 Ibs GVW
Classes 6-8A Heavy Heavy Duty Trucks, 19501 -50000 Ibs GVW
Class 8B Heavy Heavy Duty Trucks, 50000+lbs GVW
School Buses
Public Buses
Off-Highway* Agricultural, industrial/commercial, construction and
marine/recreation vehicles
Only gasoline fuel consumed by off-highway motor vehicles, such as farm and construction
equipment, is estimated. Estimating diesel fuel consumed by off-highway motor vehicles is
beyond the scope of this report.
14
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Table 4
Fuel Types
Designation Description
Gasoline Gasoline+Gasohol (E10)
Diesel 100% Diesel
E85 85%Ethanol 15% Gasoline
El00 100% Ethanol
M85 85%Methanol 15% Gasoline
M100 100% Methanol
CNG 100% Compressed Natural Gas
Tables 5-9 are copies of the 1990 model output. Several tables are provided for each
projection year:
0 Fleet Fuel Consumption
0 Fleet Vehicle Miles Traveled
0 Road MPG
0 Vehicle Registrations
0 Total Emissions
III.A. Fleet Fuel Consumption
The top one-half of the table lists the diesel and gasoline fuel consumed by light duty
vehicles, light duty trucks and by three sets of heavy duty truck classes. Also listed is
consumption by school and commercial buses. Finally, off-highway gasoline consumption is
included.
Below the conventional fuel consumption estimates are the fuel consumption estimates for
alternatively fuel vehicles. These are vehicles designed to run on ethanol (E85 and E100),
methanol (M85 and M100) and compressed natural gas (CNG).*
III.B. Fleet Vehicle Miles Traveled
The fleet vehicle miles traveled estimate is formatted in a similar fashion. Diesel and
gasoline VMT is listed in the top half of the table while VMT estimates for alternatively fueled
vehicles are listed in the bottom half.
III.C. Road
The mpg table lists road mpg both for new vehicles and for the fleet as a whole.
Since the inputs for the alternative fuels sections of the model are undergoing internal EPA
review for the Alternative Motor Fuels report, the scenarios included in this report assume all
vehicles are powered by conventional fuels.
15
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TabkS
MOBILE4 Fuel Consumption Model
1990
Fleet Fuel Consumption
(x 109 Gallons/Year, x 106 Barrels/Day)
Diesel
Gasoline
Vehicle Class
LDV
LDT
Classes 2B-5
Classes 6-8A
Class SB
School Buses
Public Buses
Off-Highway
Total LDV+LDT
Total HDV
Total Highway
Grand Total
Gallons
0.713
0.568
1.177
4.989
15.383
0.264
0.682
0.000
1.281
22.494
23.774
23.774
BBL/Day Gallons
0.046 57.217
0.037 29.133
0.077 5.717
0.325 - 1.501
1.003 0.025
0.017 0.061
0.044 0.000
0.000 3.019
0.084 86.350
1.467 7.304
1.551 93.654
1.551 96.673
Alternative Fuels
Alcohols
LDV
LDT
Classcs2B-5
Classes 6-8A
ClassSB
School Buses
Public Buses
Off-Highway
Total LDV-tLDT
Total HDV
Total Highway
Grand Total
E85
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Ethanol
E100
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Total
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
M85
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Methanol
M100
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Total
Total
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Gallons
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
BBUDav
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
BBL/Day
3.732
1.900
0.373
0.098
0.002
0.004
0.000
0.197
5.633
0.476
6.109
6.306
Gases
CNG
CCF
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Gallons
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Total
CCF
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Gallons
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Grand Total
Gallons
57.930
29.701
6.894
6.489
15.407
0.325
0.682
3.019
87.631
29.797
117.428
120.448
BBL/D;
3.779
1.937
0.450
0.423
1.005
0.021
0.044
0.197
5.716
1.944
7.660
7.857
Note: This run assumes the following fuel economy adjustments:
Standard Shortfall,
Urbanization,
No CAFE Growth.
Default M4FC
-------
Table 6
MOBILE4 Fuel Consumption Model
1990
Fleet Vehicle Miles Traveled
(xlO9 Maes/Year)
Total VMT
Diesel Gasoline
LDV 18.68 1173.31
LET 14.22 481.24
Classes 2B-5 17.25 58.93
Classes 6-8A 34.46 8.71
Class SB 83.81 0.09
School Buses 3.11 0.50
Public Buses 3.72 0.00
Total LDV+LDT 32.90 1654.55
Total HDV 142.35 68.23
Grand Total 175.25 1722.77
Total VMT
Alternative Fuels
Alcohols
Ethanol Metbanol Gases
E85 E100 Total M85 M100 Total Total CNG Total Total Total
LDV 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1191.99
LOT 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 495.45
Classes 2B-5 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 76.18
Classes6-8A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 43.17
Class 8B 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 83.90
School Buses 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3.61
Public Buses 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3.72
Total LDV-iLDT 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1687.44
Total HDV 0.00 0.00 0.00 0.00 0.00 0.00 ' 0.00 0.00 0.00 0.00 210.58
Grand Total 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1898.02
Default M4FC
-------
Table?
MOBILE4 Fuel Consumption Model
1990
RoadMPG
New Vehicle
Ethanol
Methanol
LDV
LOT
Classes 2B-5
Classes 6-8A
Class SB
School Buses
Public Buses
Total LDV+LDT
Total HDV
Grand Total
Diesel
27.63
24.95
14.55
7.01
5.49
11.79
5.45
26.13
6.52
7.24
23.03
17.26
10.62
5.93
0.00
8.20
0.00
20.89
9.65
19.67
ESS
0.00
0.00
.0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
E100
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
M85
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
M100
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
CNG
MPCCF
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Fleet
LDV
LOT
Classes 2B-5
Classes 6-8A
Class SB
School Buses
Public Buses
Total LDV-fLDT
Total HDV
Grand Total
Ethanol
Methanol
Diesel
26.21
25.02
14.66
6.91
5.45
11.79
5.45
25.68
6.33
7.37
_£as
20.51
16.52
10.31
5.80
3.46
8.20
0.00
19.16
934
18.40
_ES5
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
E100
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
M85
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
M100
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
CNG
MPCCP
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Note: This run assumes the following fuel economy adjustments:
Standard Shortfall
Urbanization,
No CAFE Growth.
Default M4PC
-------
TableS
Diesel
MOBILE4 Fuel Consumption Model
1990
Vehicle Registrations
(xl^Vefaides)
Ethanol
Methanol
Gas
E85
E100
M85
M100
Total
LDV
Lin-
Classes 2B-5
Classes 6-8A
Class SB
School Buses
Public Buses
Total LDV+LDT
Total HDV
Grand Total
1.968
1.247
1.156
1.396
1.386
0.454
0.118
3.215
4.510
7.725
122.690
43384
5.102
0.797
0.021
0.073
0.000
166.074
5.992
172.066
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
. 0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
124.658
44.631
6.258
2.193
1.407
0.527
0.118
169.289
10.503
179.791
-------
Tabfc9
MobUe4 Fuel Consumption Model
Total Emissions
(x 106 Metric Tons/Year)
HC
LDV
LET
Classes 2B-5
Classes 6-8A
Class SB
School Buses
Public Buses
Total LDV+ LOT
Total HDV
Grand Total
3.058
1.575
0.243
0.148
0.218
0.011
0.010
4.634
0.630
5.263
19.208
10.912
1.602
0.955
1.014
0.069
0.045
30.120
3.685
33.804
1.889
0.940
0.165
0.683
1.541
0.060
0.068
2.829
2.517
5.346
WJ
474.777
241.990
59383
62.104
154.465
3.082
6.841
716.766
285.874
1002.638
Default M4PC
MOBILE4 RUN: 1975-1988: no IM 11.5 RVP/1989-1991: std IM 10.5 RVP/1992-2020:
stdIM9.0RVP
-------
III.D. Vehicle Registrations and Total Emissions
The top half of last table lists total registrations by vehicle and fuel type. Total HC, CO,
NOX and CO2 emissions are listed in the second half of the table.
IV. Sensitivity
Figures 10-12 show the sensitivity gasoline consumption, VMT and CC>2 emissions to
two of the most significant MOBILE4 input assumptions: diesel penetration and VMT per
vehicle.31
The "Limited Diesel" case shows the difference in gasoline consumption that would result
by assuming that the fractions of new model year light duty vehicles and trucks that are diesel
powered remain constant at 1988 levels (0.0%, 0.2%).13
The "VMT Growth" case shows the difference in consumption that would result by
assuming that VMT per vehicle increases at 1.0% per year for light duty vehicles and light duty
trucks that operate as passenger vehicles.
Finally, "Diesel & Growth" case shows the effect of combining the two assumptions, of
constant diesel penetration rates and increasing VMT per passenger-type vehicle.
As can be seen from the figures, gasoline consumption increases as diesel penetration
declines and as VMT per vehicle increases. Both VMT and CO2 increase as VMT per vehicle
increases.
o
c
o
1990
Figure 10
Gasoline Consumption
Default
Limited Diesel
VMT Growth
Diesel & Growth
2020
21
-------
3
£
VH
8.
§
Figure 11
Total VMT
5000
4000 -
3000-
2000 -
1000-
Default
Limited Diesel
VMT Growth
Diesel & Growth
1990
1995
2000
2005
Year
2010
2015
2020
8.
H
I
s
c
o
g
w
Figure 12
Carbon Dioxide Emissions
3000
2000 -
1000
Default
Limited Diesel
VMT Growth
Diesel & Growth
0-
1990
i
1995
2000
2005
Year
2010
2015
2020
22
-------
References
-------
References
1 U.S. Environmental Protection Agency, Office of Mobile Sources, User's Guide to
MOBILE4. EPA-AA-TEB-89-01, February, 1989.
2 Energy and Environmental Analysis, Inc., The Motor Fuel Consumption Model.
Fourteenth Periodical Report, prepared for the U.S. Department of Energy,
December, 1988.
3 U.S. Environmental Protection Agency, Office of Policy Analysis, Costs and
Benefits of Reducing Lead in Gasoline. EPA-230-03 -84-005, May 1984.
4 U.S. Department of Energy, Energy Information Administration, Annual Energy
Outlook 1990. "Transportation Spreadsheet Model" (Transportation Energy Demand,
February, 1990).
5 U.S. Department of Energy, Oakridge National Laboratory, Alternative Motor Fuel
Use Model. Model Theory and Design and Users Guide. March, 1990.
6 Data Resources, Inc., U.S. Oil Outlook: A Methodological Investigation of the
Transportation Sector. Spring, 1989.
7 U.S. Environmental Protection Agency, Office of Air Quality, Planning and
Standards, User's Manual for Modified Rollback/EKMA Strategy Assessment
Model. EPA-450/4-8 1-025, July, 1981.
8 R.L. Polk and Company, Detroit, MI.
9 U.S. Department of Transportation, Federal Highway Administration, Highway
Statistics. 1985 - 1988. Table VM-1.
10 U.S. Department of Energy, Oak Ridge National Laboratory, Transportation Energy
Data Book: Edition 9. ORNL-6325, April, 1987.
1 1 Motor Vehicle Manufacturers Association of the United States, Inc., Facts & Figures
1990.
1 2 U.S. Department of Commerce, Bureau of Economic Analysis, 1985 OBERS BEA
Regional Projections. Volume 2. Metropolitan Statistical Area Projections to 2035.
13 U.S. Environmental Protection Agency, Office of Mobile Sources, Light-Duty
Automotive Technology and Fuel Economy Trends Through 1990.
EPA/AA/CTAB/90-03 , June, 1 990.
R-l
-------
References (continued)
14 U.S. Department of Commerce, Bureau of the Census, Truck Inventory and Use
Survey. 1982.
15 Energy and Environmental Analysis, Inc., Analysis of the 1982 Truck Inventory and
Use Survey. December, 1986.
16 Wards Automotive Yearbook. 52 Edition. 1990.
17 U.S. Environmental Protection Agency, Office of Mobile Sources, Heavy-Duty
Vehicle Emission Conversion Factors II 1962-2000. EPA-AA-SDSB-89-01,
October, 1988.
18 U.S. Environmental Protection Agency, Office of Mobile Sources, MOBILE4 Travel
Characteristics. July, 1990.
19 U.S. Environmental Protection Agency, Office of Mobile Sources, "Fuel
Consumption Model Inputs", Note from Karl Hellman to Ralph Stahman, October
17, 1984!
20 U.S. Environmental Protection Agency, Office of Mobile Sources, "On the Stability
of the EPA MPG Adjustment Factors", SAE 851216,1986.
21 U.S. Environmental Protection Agency, Office of Mobile Sources, "1986 Model
Year Passenger Automobile CAFE Adjustment Coefficient", May 21,1986.
22 U.S. Environmental Protection Agency, Office of Mobile Sources, "CAFE
Adjustment Coefficient for 1987 Model Year Passenger Automobiles", April 7,
1987.
23 U.S. Environmental Protection Agency, Office of Mobile Sources, "CAFE
Adjustment Coefficient for 1988 Model Year Passenger Automobiles", February 8,
1988.
24 U.S. Environmental Protection Agency, Office of Mobile Sources, "CAFE
Adjustment Coefficient for 1989 Model Year Passenger Automobiles", March 15,
1989.
25 U.S. Environmental Protection Agency, Office of Mobile Sources, "CAFE
Adjustment Coefficient for 1990 Model Year Passenger Automobiles", May 15,
1990.
26 Title 40 Code of Federal Regulations Part 600.113-88.
R-2
-------
References (continued)
27 U.S. Environmental Protection Agency, Office of Air Quality Planning and
Standards, National Air Pollutant Emission Estimates 1940-1988. March, 1990.
28 U.S. Environmental Protection Agency, Office of Air Quality Planning and
Standards, National Air Quality and Emission Trends Report 1988. March, 1990.
29 U.S. Environmental Protection Agency, Office of Mobile Sources, Volatility
Regulations for Gasoline and Alcohol Blends Sold in Calendar Years 1992 and
Beyond. Air Quality Analysis. 1990.
30 U.S. Environmental Protection Agency, Office of Mobile Sources, Interim
Regulations For Cold Temperature Carbon Monoxide Emissions Air Quality
Analysis. 1990.
31 U.S. Environmental Protection Agency, Office of Mobile Sources, "Rationale for
Estimating Possible Increase in VMT/Vehicle", December 11,1990.
R-3
-------
Appendix A
Model Input Tables
-------
Historical and Predicted Vehicle Stock
(millions of vehicles)
Year
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
Polk
Cars
35.924
38.516
39.770
42.202
44.387
47.378
49.804
51.432
52.493
55.087
57.103
58.854
60.920
63.493
66.051
68.940
71.264
72.968
75.358
78.495
80.448
83.137
86.439
89.805
92.608
95.241
97.818
99.904
102.957
104.677
104.564
105.839
106.867
108.961
112.019
114.662
FHwA M4FC
Cars Cars
40.339
42.688
43.823
46.429
48.468
52.145
54.211
55.918
56.891
59.454
61.671
63.421
66.085
69.038
71.995
75.258
78.125
80.414
83.693
86.861
89.280
92.799
96.860
101.762
104.856
106.713
110.189
113.696
116.575
120.248
121.724
123.291
123.746 106.867
126.138 108.961
128.271 112.019
131.864 114.662
Polk
Trucks
7.577
8.065
8.420
8.693
8.800
9.162
9.544
9.776
10.057
10.532
10.803
11.043
11.463
11.902
12.445
13.127
14.357
14.988
15.685
16.586
17.688
18.462
19.773
21.412
23.312
24.813
26.560
28.222
30.565
33.894
35.268
36.069
36.986
38.144
40.144
42.389
FHwA
Trucks
8.457
8.847
9.049
9.375
9.610
10.101
10.476
10.711
10.878
11.343
11.601
11.919
12.406
12.957
13.588
14.340
15.029
16.531
17.347
18.235
19.127
20.200
21.646
23.233
25.077
26.238
28.257
30.054
32.203
33.870
34.166
34.995
35.703
37.671
37.978
39.790
M4FC
Trucks
36.986
38.144
40.144
42.389
Polk FHwA
Year Cars Cars
1986 117.268 135.431
1987 119.849 137.208
1988 121.519 141.252
1989 122.758
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
M4FC
Cars
117.268
119.849
121.519
122.758
124.658
126.556
128.535
130.591
132.720
134.918
137.031
139.203
141.431
143.712
146.044
148.353
150.707
153.104
155.542
158.020
160.496
163.007
165.554
168.133
170.745
173.389
176.062
178.765
181.497
184.257
186.638
189.037
191.454
193.887
196.338
Polk
Trucks
44.827
47.343
50.223
53.201
54.937
57.490
60,018
62.524
65.014
67.487-
69.865
72.228
74.588
76.940
79.291
81.597
83.907
86.220
88.539
90.860
93.166
95.484
97.808
100.146
102.494
104.857
107.236
109.631
112.040
114.468
116.656
118.853
121.065
123.287
125.525
FHwA M4FC
Trucks Trucks
40.663 44.827
41.747 47.343
43.145 50.223
53.201
A-l
-------
Vehicle Stock
(millions of vehicles)
Year
* ^"***
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
LDV
106.867
108.961
112.019
114.662
117.268
119.849
121.519
122.758
124.658
126.556
128.535
130.591
132.720
134.918
137.031
139.203
141.431
143.712
146.044
148.353
150.707
153.104
155.542
158.020
160.496
163.007
165.554
168.133
170.745
173.389
176.062
178.765
181.497
184.257
186.638
189.037
191.454
193.887
196.338
Car-Like
LDT1
7.598
8.563
8.492
8.871
9.322
9.832
11.289
13.211
14.507
15.732
16.907
18.036
19.125
20.175
21.161
22.115
23.040
23.938
24.812
25.650
26.468
27.268
28.051
28.820
29.567
30.302
31.026
31.741
32.447
33.145
33.837
34.523
35.203
35.879
36.470
37.055
37.636
38.213
38.788
Commrcl
LDT1
13.063
12.286
13.229
14.010
15.009
15.915
15.911
15.809
15.831
16.222
16.622
17.031
17.450
17.877
18.313
18.759
19.218
19.688
20.171
20.666
21.174
21.696
22.232
22.782
23.346
23.926
24.521
25.131
25.758
26.401
27.061
27.737
28.431
29.142
29.859
30.594
31.349
32.122
32.916
LPT2
10.299
10.622
11.151
11.428
12.129
12.636
13.632
14.184
14.293
14.713
15.141
15.578
16.022
16.474
16.903
17.337
17.778
18.224
18.677
19.120
19.569
20.022
20.481
20.943
21.402
21.865
22.331
22.801
23.275
23.752
24.232
24.716
25.202
25.692
26.099
26.505
26.911
27.316
27.720
Class
2B
2.471
3.042
3.436
4.053
4.195
4.601
4.808
5.219
5.464
5.827
6.191
6.557
6.925
7.295
7.652
8.011
8.372
8.733
9.096
9.453
9.812
10.171
10.531
10.892
11.250
11.609
11.968
12.328
12.688
13.049
13.411
13.773
14.136
14.499
14.814
15.127
15.439
15.748
16.056
Class
3
0.092
0.090
0.088
0.105
0.102
0.101
0.100
0.098
0.094
0.091
0.088
0.086
0.084
0.081
0.079
0.077
0.074
0.072
0.070
0.068
0.066
0.064
0.062
0.060
0.058
0.057
0.055
0.053
0.051
0.050
0.048
0.047
0.045
0.044
0.042
0.041
0.039
0.038
0.036
Class
4
0.237
0.231
0.227
0.221
0.216
0.213
0.212
0.208
0.198
0.192
0.187
0.182
0.177
0.172
0.167
0.162
0.158
0.153
0.149
0.144
0.140
0.136
0.132
0.128
0.124
0.120
0.116
0.112
0.109
0.105
0.102
0.099
0.096
0.092
0.089
0.086
0.083
0.080
'0.077
Class
5
0.407
0.399
0.396
0.392
0.388
0.388
0.392
0.391
0.379
0.375
0.371
0.367
0.364
0.361
0.358
0.354
0.351
0.349
0.346
0.344
0.341
0.339
0.337
0.335
0.334
0.332
0.331
0.329
0.328
0.327
0.326
0.326
0.325
0.325
0.323
0.322
0.321
0.320
0.319
Class
6
0.639
0.649
0.666
0.676
0.679
0.695
0.717
0.733
0.727
0.736
0.746
0.758
0.769
0.782
0.793
0.805
0.818
0.832
0.847
0.861
0.876
0.892
0.907
0.923
0.938
0.954
0.970
0.987
1.003
1.020
1.037
1.054
1.071
1.088
1.102
1.116
1.130
1.144
1.158
Class
7
0.359
0.401
0.467
0.536
0.600
0.677
0.764
0.851
0.912
0.995
1.079
1.165
1.253
1.341
1.428
1.514
1.600
1.686
1.771
1.854
1.938
2.022
2.106
2.190
2.273
2.356
2.439
2.523
2.606
2.689
2.772
2.855
2.938
3.022
3.095
3.167
3.239
3.311
3.382
Class
8A
0.404
0.410
0.425
0.438
0.456
0.467
0.483
0.495
0.491
0.498
0.506
0.514
0.523
0.532
0.541
0.550
0.559
0.568
0.578
0.587
0.597
0.607
0.617
0.627
0.637
0.648
0.658
0.669
0.679
0.690
0.701
0.712
0.723
0.735
0.744
0.753
0.762
0.771
0.780
Class
8B
0.858
0.904
1.006
1.085
1.143
1.217
1.299
1.372
1.396
1.451
1.507
1.563
1.621
1.681
1.740
1.801
1.862
1.925
1.988
2.050
2.112
2.175
2.239
2.302
2.365
2.428
2.492
2.556
2.620
2.684
2.749
2.814
2.879
2.944
3.000
3.055
3.110
3.165
3.220
School
Buses
0.446
0.433
0.446
0.459
0.472
0.485
0.499
0.513
0.527
0.540
0.554
0.568
0.582
0.596
0.610
0.623
0.637
0.651
0.665
0.679
0.693
0.707
0.722
0.736
0.750
0.765
0.779
0.794
0.808
0.823
0.838
0.853
0.868
0.883
0.897
0.910
0.924
0.937
0.951
Public
Buses
0.113
0.114
0.115
0.115
0.116
0.116
0.117
0.117
0.118
0.118
0.119
0.119
0.119
0.120
0.120
0.120
0.121
0.121
0.121
0.121
0.121
0.121
0.122
0.122
0.122
0.122
0.122
0.122
0.122
0.122
0.122
0.122
0.123
0.123
0.122
0.122
0.122
0.122
0.122
A-2
-------
Registration Distributions
Classes 2B-8B
Age
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
LEV
0.084
0.080
0.077
0.073
0.069
0.066
0.062
0.058
0.055
0.051
0.047
0.043
0.040
0.036
0.032
0.029
0.025
0.021
0.018
0.014
0.010
0.007
0.003
0.000
0.000
0.000
0.000
0.000
0.000
0.000
LPT
0.100
0.095
0.089
0.084
0.079
0.074
0.068
0.063
0.058
0.053
0.047
0.042
0.037
0.032
0.026
0.021
0.016
0.011
0.005
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Gas
0.140
0.120
0.104
0.090
0.077
0.066
0.057
0.049
0.043
0.037
0.032
0.027
0.024
0.020
0.017
0.015
0.013
0.011
0.010
0.008
0.007
0.006
0.005
0.005
0.004
0.003
0.003
0.003
0.002
0.002
Diesel
0.179
0.147
0.121
0.099
0.082
0.067
0.055
0.045
0.037
0.031
0.025
0.021
0.017
0.014
0.011
0.009
0.008
0.006
0.005
0.004
0.003
0.003
0.002
0.002
0.002
0.001
0.001
0.001
0.001
0.001
A-3
-------
LJDVand
Car-Like LDT1
Commrcl LDT1
VMT Distributions
(thousands of miles/year)
LDT2
Class 2B
Age Gas
Diesel
Classes 3-5
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
13.118
12.408
11.737
11.103
10.503
9.935
9.398
8.889
8.409
7.954
7.524
7.117
6.733
6.369
6.024
5.698
5.390
5.099
4.823
4.562
4.562
4.562
4.562
4.562
4.562
4.562
4.562 '
4.562
4.562
4.562
17.825
16.478
15.233
14.081
13.017
12.033
11.124
10.283
9.506
8.788
8.123
7.509
6.942
6.417
5.932
5.484
5.069
4.686
4.332
4.005
4.005
4.005
4.005
4.005
4.005
4.005
4.005
4.005
4.005
4.005
15.640
14.590
13.610
12.696
11.843
11.048
10.306
9.614
8.968
8.366
7.804
7.280
6.791
6.335
5.909
5.512
5.142
4.797
4.475
4.174
4.174
4.174
4.174
4.174
4.174
4.174
4.174
4.174
4.174
4.174
20.140
17.572
15.432
13.639
12.133
10.863
9.788
8.877
8.103
7.444
6.883
6.405
5.999
5.655
5.365
5.123
4.924
4.763
4.637
4.543
4.543
4.543
4.543
4.543
4.543
4.543
4.543
4.543
4.543
4.543
17.608
16.217
14.937
13.758
12.671
11.671
10.749
9.901
9.119
8.399
7.736
7.125
6.562
6.044
5.567
5.127
4.723
4.350
4.006
3.690
3.690
3.690
3.690
3.690
3.690
3.690
3.690
3.690
3.690
3.690
20.140
17.572
15.432
13.639
12.133
10.863
9.788
8.877
8.103
7.444
6.883
6.405
5.999
5.655
5.365
5.123
4.924
4.763
4.637
4.543
4.543
4.543
4.543
4.543
4.543
4.543
4.543
4.543
4.543
4.543
18.211
16.767
15.437
14.213
13.086
12.048
11.093
10.213
9.403
8.657
7.971
7.339
6.757
6.221
5.728
5.273
4.855
4.470
4.116
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
17.608
16.217
14.937
13.758
12.671
11.671
10.749
9.901
9.119
8.399
7.736
7.125
6.562
6.044
5.567
5.127
4.723
4.350
4.006
3.690
3.690
3.690
3.690
3.690
3.690
3.690
3.690
3.690
3.690
3.690
18.211
16.767
15.437
14.213
13.086
12.048
11.093
10.213
9.403
8.657
7.971
7.339
6.757
6.221
5.728
5.273
4.855
4.470 '
4.116
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
23.611
20.947
18.583
16.486
14.625
12.975
11.511
10.212
9.059
8.037
7.130
6.325
5.612
4.978
4.416
3.918
3.476
3.084
2.736
2.427
2:427
2.427
2.427
2.427
2.427
2.427
2.427
2.427
2.427
2.427
A-4
-------
VMT Distributions
(thousands of miles/year)
Buses
Age
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
Cl
Gas
18.211
16.767
15.437
14.213
13.086
12.048
11.093
10.213
9.403
8.657
7.971
7.339
6.757
6.221
5.728
5.273
4 85S
*T.O JJ
4.470
4.116
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
ass 6
Diesel
43.946
40.504
37.332
34.408
31.713
29.229
26.939
24.829
22.885
21.092
19.440
17.918
16.514
15.221
14.029
12.930
U917
. " 1 1
10.984
10.123
9.331
9.331
9.331
9.331
9.331
9.331
9.331
9.331
9.331
9.331
9.331
Cla
Gas
18.211
16.767
15.437
14.213
13.086
12.048
11.093
10.213
9.403
8.657
7.971
7.339
6.757
6.221
5.728
5.273
48SS
.0 JJ
4.470
4.116
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
ss7
Diesel
43.946
40.504
37.332
34.408
31.713
29.229
26.939
24.829
22.885
21.092
19.440
17.918
16.514
15.221
14.029
12.930
U017
*y i /
10.984
10.123
9.331
9.331
9.331
9.331
9.331
9.331
9.331
9.331
9.331
9.331
9.331
Clas
Gas
18.211
16.767
15.437
14.213
13.086
12.048
11.093
10.213
9.403
8.657
7.971
7.339
6.757
6.221
5.728
5.273
/I 85S
H.OJ J
4.470
4.116
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
s8A
Diesel
43.946
40.504
37.332
34.408
31.713
29.229
26.939
24.829
22.885
21.092
19.440
17.918
16.514
15.221
14.029
12.930
UO1 1
,y i i
10.984
10.123
9.331
9.331
9.331
9.331
9.331
9.331
9.331
9.331
9.331
9.331
9.331
Clasi
Gas
18.211
16.767
15.437
14.213
13.086
12.048
11.093
10.213
9.403
8.657
7.971
7.339
6.757
6.221
5.728
5.273
A RSS
H.O JJ
4.470
4.116
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
3.789
s 8B School
Diesel Gas Diesel
86.375 6.853 6.853
79.434
73.051
67.181
61.782
56.817
52.252
48.053
44.191
40.640
37.374
34.371
31.609
29.069
26.733
24.585
)) /;no
££,v\Jy
20.792
19.121
17.585
17.585
17.585
17.585
17.585
17.585
nsss
. J o J ~
17.585
17.585
17.585
17.585
Public
Gas Diesel
31.525 31.525
A-5
-------
Diesel Penetration Rates
Year
1962-
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000+
LDV&
Car-Like
LDT1
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.025
0.048
0.062
0.032
0.012
0.016
0.001
0.000
0.009
0.017
0.014
0.022
0.020
0.037
0.035
0.042
0.050
0.050
0.050
0.050
0.050
0.050
Commrcl
LDT1&
LPT2
0.000
0.000
0.000.
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.010
0.015
0.048
0.082
0.092
0.042
0.026
0.011
0.020
0.009
0.027
0.044
0.062
0.080
0.097
0.115
0.132
0.150
0.150
0.150
0.150
0.150
0.150
Buses
Class
2B
0.000
.0.001
0.001
0.002
0.003
0.002
0.001
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.001
0.000
0.041
0.081
0.122
0.162
0.184
0.198
0.216
0.232
0.250
0.260
0.270
0.280
0.290
0.300
0.300
0.300
0.300
0.300
0.300
0.300
0.300
0.300
Q asses
3-5
0.014
0.018
0.022
0.026
0.029
0.031
0.022
0.012
0.003
0.003
0.003
0.004
0.004
0.005
0.003
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Class
6
0.042
0.063
0.084
0.105
0.100
0.094
0.088
0.082
0.076
0.054
0.031
0.034
0.038
0.041
0.071
0.100
0.106
0.174
0.242
0.309
0.377
0.399
0.493
0.579
0.527
0.590
0.610
0.626
0.642
0.656
0.668
0.679
0.688
0.695
0.699
0.700
0.700
0.700
0.700
Class
7
0.421
0.436
0.442
0.447
0.413
0.379
0.364
0.348
0.333
0.341
0.348
0.382
0.415
0.449
0.514
0.578
0.615
0.606
0.598
0.589
0.580
0.617
0.589
0.627
0.617
0.635
0.646
0.655
0.662
0.670
0.677
0.684
0.689
0.694
0.698
0.700
0.700
0.700
0.700
Class
8A
0.600
0.616
0.624
0.632
0.583
0.535
0.514
0.492
0.470
0.482
0.492
0.540
0.586
0.634
0.726
0.770
0.794
0.818
0.841
0.865
0.899
0.962
0.962
0.973
0.981
0.989
0.994
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
Class
8B
0.547
0.595
0.642
0.690
0.721
0.751
0.809
0.867
0.925
0.923
0.923
0.921
0.920
0.920
0.960
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
School
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.001
0.011
0.051
0.116
0.291
0.316
0.342
0.350
0.589
0.690
0.745
0.794
0.830
0.861
0.886
0.910
0.929
0.946
0.961
0.972
0.983
0.994
1.000
1.000
Public
0.547
0.595
0.642
0.690
0.721
0.751
0.809
0.867
0.925
0.923
0.923
0.921
0.920
0.914
0.919
0.943
0.943
0.965
0.979
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
A-6
-------
LDV
Fuel Economies and Diesel Advantage Factors
1JDT
Year
1962-
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000+
City
Gas
13.01
13.01
13.01
13.01
13.01
13.01
12.81
12.91
12.91
12.50
12.60
12.40
12.40
13.70
15.20
16.00
17.20
17.70
20.30
21.70
22.30
22.10
22.40
23.00
23.70
23.90
24.20
23.70
23.40
23.40
23.40
23.40
23.40
23.40
23.40
23.40
23.40
23.40
23.40
Hwy
Gas
18.52
18.52
18.52
18.52
18.52
18.52
18.23
18.37
18.37
17.80
17.94
17.65
17.65
19.50
21.30
22.30
24.50
24.60
29.00
31.10
32.70
32.70
33.30
34.30
35.50
35.90
36.60
36.30
36.00
36.00
36.00
36.00
36.00
36.00
36.00
36.00
36.00
36.00
36.00
Dsl
Fctr
1.73
1.73
1.73
1.73
1.73
1.73
1.73
1.73
1.73
1.73
1.73
1.73
1.73
1.73
1.62
1.51
1.42
1.35
1.26
1.23
1.22
1.21
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
City
Gas
11.67
11.67
11.67
11.67
11.67
11.67
11.46
11.57
11.57
11.15
11.25
11.05
11.05
12.10
12.80
14.00
13.80
13.40
16.50
17.80
18.10
18.30
17.90
18.00
18.80
18.80
18.30
18.10
18.10
18.10
18.10
18.10
18.10
18.10
18.10
18.10
18.10
18.10
18.10
Hwy
Gas
15.63
15.63
15.63
15.63
15.63
15.63
15.35
15.49
15.49
14.93
15.07
14.79
14.79
16.20
16.90
18.10
17.50
16.80
21.90
23.90
24.40
25.20
24.80
24.90
25.90
26.50
26.20
25.70
26.10
26.10
26.10
26.10
26.10
26.10
26.10
26.10
26.10
26.10
26.10
Dsl
^Fctr
1.73
1.73
1.73
1.73
1.73
1.73
1.73
1.73
1.73
1.73
1.73
1.73
1.73
.73
.62
.51
.42
.35
.26
1.23
1.22
1.21
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
1.20
Clas
Gas
10.76
10.76
10.76
10.76
10.76
10.76
10.76
10.76
10.76
10.76
10.76
10.76
11.02
11.27
11.54
11.79
12.05
12.30
12.56
12.81
13.07
13.08
13.09
13.12
13.16
13.16
13.16
13.16
13.16
13.16
13.16
13.16
13.16
13.16
13.16
13.16
13.16
13.16
13.16
s2B
£sl
^_
16.61
16.94
16.95
16.98
17.42
17.05
17.05
17.05
17.05
17.05
17.05
17.05
17.05
17.05
17.05
17.05
17.05
17.05
17.05
17.05
Classe
.Gas
7.64
7.64
7.64
7.64
7.64
7.64
7.64
7.64
7.64
7.64
7.64
7.64
7.66
7.69
7.71
7.73
7.76
7.78
7.81
7.83
7.85
7.86
7.86
7.88
7.90
7.90
7.90
7.90
7.90
7.90
7.90
7.90
7.90
7.90
7.90
7.90
7.90
7.90
7.90
s 3-4
Dsl
7.66
7.66
7.66
7.66
7.66
7.66
7.66
7.66
7.66
7.66
7.66
7.66
8.24
8.82
9.40
Class
Gas
7.64
7.64
7.64
7.64
7.64
7.64
7.64
7.64
7.64
7.64
7.64
7.64
7.66
7.69
7.71
7.73
7.76
7.81
7.81
7.83
7.85
7.86
7.88
7.90
7.94
7.94
7.94
7.94
7.94
7.94
7.94
7.94
7.94
7.94
7.94
7.94
7.94
7.94
7.94
5
Dsl
7.66
7.66
7.66
7.66
7.66
7.66
7.66
7.66
7.66
7.66
7.66
7.66
8.24
8.82
9.40
A-7
-------
Fuel Economies and Diesel Advantage Factors
Class 6 Class 7 Class 8A Class 8B School Bus Public Bus
Year Gas Dsl Gas Dsl Gas Dsl Gas Dsl Gas Dsl Gas Dsl
1962-
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000+
6.83
6.83
6.83
6.83
6.83
6.83
6.83
6.83
6.83
6.83
6.83
6.83
6.71
6.65
6.66
6.72
6.81
6.93
7.12
7.39
7.72
7.78
7.84
7.90
7.96
7.96
7.96
7.96
7.96
7.96
7.96
7.96
7.96
7.96
7.96
7.96
7.96
7.96
7.96
6.89
6.89
6.89
6.89
6.89
6.89
6.89
6.89
6.89
6.89
6.89
6.89
7.20
7.52
7.84
8.15
8.47
8.79
9.11
9.42
9.74
9.83
9.92
10.00
10.06
10.06
10.06
10.06
10.06
10.06
10.06
10.06
10.06
10.06
10.06
10.06
10.06
10.06
10.06
5.44
5.44
5.44
5.44
5.44
5.44
5.44
5.44
5.44
5.44
5.44
5.44
5.46
5.48
5.50
5.55
5.70
5.90
6.06
6.13
6.12
6.17
6.20
6.25
6.28
6.28
6.28
6.28
6.28
6.28
6.28
6.28
6.28
6.28
6.28
6.28
6.28
6.28
6.28
6.65
6.65
6.65
6.65
6.65
6.65
6.65
6.65
6.65
6.65
6.65
6.65
6.62
6.61
6.65
6.82
7.18
7.78
8.33
8.61
8.76
8.83
8.89
8.96
9.03
9.03
9.03
9.03
9.03
9.03
9.03
9.03
9.03
9.03
9.03
9.03
9.03
9.03
9.03
5.04
5.04
5.04
5.04
5.04
5.04
5.04
5.04
5.04
5.04
5.04
5.04
5.19
5.33
5.24
5.62
5.77
5.92
6.06
6.20
6.36
6.40
6.44
6.49
6.53
6.53
6.53
6.53
6.53
6.53
6.53
6.53
6.53
6.53
6.53
6.53
6.53
6.53
6.53
6.06
6.06
6.06
6.06
6.06
6.06
6.06
6.06
6.06
6.06
6.06
6.06
6.05
6.06
6.08
6.18
6.28
6.37
6.42
6.47
6.51
6.57
6.63
6.68
6.74
6.74
6.74
6.74
6.74
6.74
6.74
6.74
6.74
6.74
6.74
6.74
6.74
6.74
6.74
3.98
3.98
3.98
3.98
3.98
3.98
3.98
3.98
3.98
3.98
3.98
3.98
4.16
4.32
4.50
5.12
5.14
5.18
5.20
5.24
5.26
5.29
5.30
5.32
5.35
5.37
5.38
5.41
5.42
5.44
5.46
5.48
5.50
5.61
5.61
5.61
5.61
5.61
5.61
5.61
5.61
5.61
5.61
5.61
5.61
5.64
5.69
5.73
5.77
5.85
5.94
6.04
6.18
6.38
6.38
6.40
6.40
6.43
6.43
6.43
6.43
6.43
6.43
6.43
6.43
6.43
6.43
6.43
6.43
6.43
6.43
6.43
-_
8.68
8.72
8.73
8.73
8.74
9.08
9.09
9.12
9.18
9.24
9.30
9.36
9.43
9.49
9.55
9.61
9.67
9.73
9.79
9.85
9.91
9.98
10.04
10.10
10.16
10.22
12.62
12.77
12.91
13.07
13.22
13.37
13.52
13.67
13.82
13.97
14.13
14.27
14.42
14.58
14.72
14.87
15.03
15.17
15.33
5.69
6.00
5.99
5.96
6.01
5.98
5.92
5.89
5.95
6.01
6.08
6.14
6.20
6.26
6.33
6.39
6.45
6.51
6.57
6.64
6.70
6.76
6.82
6.89
6.95
7.01
A-8
-------
Appendix B
Model Input Figures
-------
MOBILE4 Fuel Consumption Model
LDV Registration Distributions
Ol
to
18 -
17 -_
16
15 -
14-
13
12 -
11
10-
9-
8-
7-
6-
5-
4-
3-
2-
1-
0-
0
10
15
20
25
30
Age
L.
-------
MOBILE4 Fuel Consumption Model
Classes 2B-8B Registration Distributions
u.
5
«*
«
u
IIIIIIIIIIIIIIII
Gas
Diesel
30
Age
-------
in
O
o
3
O
H
s
90
80-
70-
60 -
50-
40-
30
20
10
MOBILE4 Fuel Consumption Model
LDV VMT
" Diesel
0
10
15
20
25
30
Age
09
V
01
O
>
90-
80-
70-
60-
50-
40-
30-
20-
10-
0-
MOBILE4 Fuel Consumption Model
LDT1 VMT
I "
10
Illlllllllllllll
Gas
Diesel
15
20
25
30
Age
-------
L.
OJ
O
l/i
o
3
O
a
H
s
90
80
70-
60-
50-
40-
30-
20-
10-
0'
MOBILE4 Fuel Consumption Model
LDT2 VMT
0
10
15
20
25
30
Age
a
V
O
a
Wl
3
O
H
s
90- -
80-
70-
60-
50-
40-
30-
20-
10-
0- -
0
MOBILE4 Fuel Consumption Model
Class 2B VMT
Gas
Diesel
10
15
20
25
30
Age
-------
O
a
a
90
80-
70-
60-
50-
40
30-
20-
10-
0-
MOBILE4 Fuel Consumption Model
Classes 3-5 VMT
Illlllllllllllll
Gas
Diesel
0
10
15
20
25
30
Age
09
41
o
a
>
MOBILE4 Fuel Consumption Model
Classes 6-8A VMT
Gas
Diesel
25
30
Age
-------
MOBILE4 Fuel Consumption Model
Class 8B VMT
90
a
a
3
O
-C
m*m*^m
niiiiiiii
Gas
"" Diesel
10
15
20
25
30
Age
-------
o
a,
S
ft
a
a.
Ed
MOBILE4 Fuel Consumption Model
LDV City and Highway Fuel Economy
20
10-
................
City Gas
City Diesel
Hwy Gas
Hwy Diesel
1960
1970
1980
1990
2000
Model Year
|
V
.a
tt.
W
MOBILE4 Fuel Consumption Model
LDT1-LDT2 City and Highway Fuel Economy
City Gas
City Diesel
^~"^~ Hwy Gas
Hwy Diesel
1960 1965 1970 1975 1980 1985 1990 1995 2000
Model Year
-------
MOBILE4 Fuel Consumption Model
Class 2B Fuel Economy
o
Q.
-
at
a,
w
a.
eu
w
1960 1965 1970 1975 1980 1985 1990 1995 2000
MOBILE4 Fuel Consumption Model
Classes 3-5 Fuel Economy
40-
30-
20
10-
Gas
Diesel
0
1960 1965 1970 1975 1980 1985 1990 1995 2000
Model Year
-------
u
eu
S
eg
eu
w
MOBILE4 Fuel Consumption Model
Class 6 Fuel Economy
50
40-
30-
20-
10 -
«II«IBII»I«IIIIII»HII*MIIIBMIIM«I
Illlllllllllllll
Gas
Diesel
0
1960 1965 1970 1975 1980 1985 1990 1995 2000
Model Year
EL,
.o
eu
a
50
40-
30-
20-
10-
MOBILE4 Fuel Consumption Model
Class 7 Fuel Economy
Illlllllllllllll
Gas
Diesel
1960 1965 1970 1975 1980 1985 1990 1995 2000
Model Year
-------
o
a.
a
a,
u
MOBILE4 Fuel Consumption Model
Class 8A Fuel Economy
50
40-
30-
20-
10-
Illlllllllllllll
Gas
Diesel
0
1960 1965 1970 1975 1980 1985 1990 1995 2000
Model Year
O
Pu
S
"3
.0
=8
eu
td
50
40-
30-
20-
10-
MOBILE4 Fuel Consumption Model
Class SB Fuel Economy
Gas
1111 Diesel
0
1960 1965 1970 1975 1980 1985 1990 1995 2000
Model Year
-------
o
a.
S
ca
MOBILE4 Fuel Consumption Model
Bus Fuel Economy
50
40 H
30 H
20 H
10 H
1975
,. in iiii>m» iinii»i»»»"
1980
1985
1990
Illllllllllllllt
School Gas
School Diesel
Commercial Diesel
1995
2000
Calendar Year
-------
-------
o
o
o
V
a
-------
MOBILE4 Fuel Consumpt on Model
Class 6 Diesel Penetration
o
e
V
a.
0
1960 1965 1970 1975 1980 1985 1990 1995 2000
Model Year
MOBILE4 Fuel Consumption Model
Class 7 Diesel Penetration
eg
i.
*-»
-------
MOBILE4 Fuel Consumption Model
Class 8A Diesel Penetration
01
c
O)
ft.
Ol
5
0
1960 1965 1970 1975 1980 1985 1990 1995 2000
Model Year
MOBILE4 Fuel Consumption Model
Class SB Diesel Penetration
a
u
-------
MOBILE4 Fuel Consumption Model
Bus Diesel Penetration
c
o
-------
Appendix C
Model Input Prompts
-------
Input Prompts
The MOBILE4 Fuel Consumption model interactively asks for the following inputs
pertaining to the scenario being run:
Prompt: PLEASE ENTER THE SCENARIO DESCRIPTION
s
Response: Enter an 80-character description of the scenario being run.
Prompt: PLEASE ENTER THE START YEAR AS A 2-DIGIT NUMBER
Response: Enter the beginning year of the run. Enter only the last two digits of the year.
Thus, "10" will be interpreted as 2010. .
Any year between 1982 and 2020 may be entered.
Prompt: PLEASE ENTER THE 2-DIGIT ENDING YEAR
Response: Enter the ending year of the run. As before, enter only the last two digits of the
year.
Any year between 1982 and 2020 may be entered. However, the ending year
must be equal to or greater than the starting year.
Prompt: PLEASE ENTER THE INCREMENT YEAR FACTOR AS INTEGER VALUE
Response: Enter the yearly increment. This value is the step size, in years, between the
beginning and ending years.
For example, if the increment is 1, then every year between the starting and
ending year, inclusive, is output. If the increment is 5, then every fifth year is
produced.
Prompt: DO YOU WANT TO REPLACE THE LDV AND/OR LOT DIESELIZATION
RATES? (1=YES, 2=NO)
Response: The model is asking whether to override the MOB1LE4 emissions model diesel
penetration rates.
If answered affirmatively, the model will produce the following prompts.
Otherwise, it will skip to the VMT ADJUSTMENT prompt below.
Prompt: PLEASE ENTER THE NEW LDV & CAR-
LIKE LDT1 DIESELIZATION RATE (.000-
.005)
Response: Enter a constant, replacement diesel
penetration rate for LDVs and car-like
LDTls. The rate must lie in the range .00-
.05 (0-5%), inclusive.
C-l
-------
Prompt: PLEASE ENTER THE 2-DIGIT
STARTING YEAR FOR THE NEW LDV &
CAR-LIKE LDT1 DIESELIZATION RATE
(82+)
Response: Input the year in which the new diesel
penetration rate becomes effective. The rate
will become effective that year and continue
at a constant value thereafter. As before, enter
only the last 2 digits of the year.
The year must be no earlier than 1982.
Prompt: PLEASE ENTER THE COMMERCIAL
LDT1-LDT2 DIESELIZATION RATE (.000-
.150)
Response: Enter the replacement diesel penetration rate
for commercial LDTl and LDT2. The rate
must lie in the range .00-.15 (0-15%),
inclusive.
Prompt: PLEASE ENTER THE 2-DIGIT
STARTING YEAR FOR THE
COMMERCIAL LDT1-LDT2
DIESELIZATION RATE (82+)
This input is analogous to that entered for
LDV & car-like LDTl.
Prompt: PLEASE SELECT THE VMT ADJUSTMENT METHOD
1 - NO ADJUSTMENT
2 - VMT/VEH GROWTH RATE
Response: This prompt asks whether you want to increase the amount of miles vehicles
travel per year. If answered affirmatively, the following prompts are displayed.
Otherwise, the CHANGE SCENARIO prompt will appear next.
Prompt: PLEASE ENTER THE LDV & CAR-LIKE
LDTl VMT/VEH GROWTH RATE
(%/YEAR)
Response: Enter the VMT growth rate, in percent per
year, for LDV and car-like LDTl.
The rate can be any decimal value, positive or
negative; (e.g., 1.0).
C-2
-------
Prompt: PLEASE ENTER THE TRUCK VMT/VEH
GROWTH RATE (%/YEAR)
Response: Enter the VMT growth rate, in percent per
year, for all remaining trucks (commercial
LDT1 and heavier).
The rate can be any decimal value, positive or
negative; (e.g., 1.0).
Prompt: PLEASE ENTER THE 2-DIGIT VMT
ADJUSTMENT BASE YEAR
Response: Enter the base year for the VMT per vehicle
growth calculations is entered in the usual
digit fashion. Any year from 1982 through
2020 is allowed.
Only those years after the base year are
affected.
Prompt: DO YOU WANT TO CHANGE SCENARIO PARAMETERS? (1=YES,
2=NO)
Response: If a mistake was made in entering the scenario input values, this prompt allows
you to abort the run and re-enter the correct values.
Prompt: DO YOU WANT TO RUN ANOTHER SCENARIO? (1=YES, 2=NO)
Response: This prompt allows you to run multiple scenarios. If answered affirmatively,
you will be returned to the SCENARIO DESCRIPTION prompt. Otherwise the
run will end.
C-3
------- |