About This Life Cycle Cost Model
Cost Model was developed in order to allow users to evaluate, over their
useful lives, the total cost of ownership of vehicles with different types of
propulsion systems and/or that operate on different fuels (i.e. diesel versus
natural gas versus hydrogen fuel cell). The model is also designed to allow
analysis of different types of vehicles, including but not limited to, buses,
commercial trucks, and fork lifts.
of total cost included in the model are: vehicle purchase; purchase/installation
of required fueling infrastructure; purchase/installation of required depot
modifications, special tools, and special infrastructure; initial driver/operator,
mechanic and manager training; annual driver/operator labor costs; annual
vehicle maintenance costs; annual fuel costs; annual maintenance and operating
cost of required fueling infrastructure, depot modifications, special tools,
and special infrastructure; periodic vehicle overhaul costs, and annual
refresher training costs.
analysis does not include full overhead for management functions, except to the
extent that they are included in the hourly labor rates input by the user for
each employee type, or in per-mile vehicle maintenance costs.
model was designed to be dynamic, such that major assumptions about all of the
above cost elements can be changed as new information becomes available, or to
conduct what if and sensitivity analyses. It was also designed to be as flexible as possible so that it could be
used to evaluate a wide range of vehicle, fuel, and technology types.
vehicle propulsion technologies require significant investments in new fueling
infrastructure, depot modifications, and special tools. Other vehicle types require special
infrastructure. The model is set up to allow the user to include the cost of
this infrastructure as applicable, and to input an appropriate useful life for
each. In the model the cost of these
infrastructure investments are amortized over their entire useful lives, which
in many cases is longer than the useful life of the vehicles.
model is set up such that up to ten vehicle/technology types can be analyzed at
the same time: two vehicle/technology
types that operate on each of two different liquid fuels (i.e. diesel fuel and
gasoline), two vehicle/technology types that operate on each of two different
gaseous fuels (i.e. natural gas and hydrogen), and two vehicle types that
operate exclusively on electricity taken from the electric grid (i.e. battery
electric or trolley vehicles). For all vehicles that operate on liquid or
gaseous fuels the model also allows the user to designate them as plug-in
hybrid vehicles that derive some of their energy from the electrical grid and
some from the liquid or gaseous fuel.
of the fuel/technology combinations that can be analyzed using the model
include: standard gasoline or diesel vehicles; compressed natural gas, propane,
or hydrogen ICE vehicles; diesel, gasoline, or natural gas hybrid-electric
vehicles; diesel, gasoline, or natural gas plug-in hybrid-electric vehicles;
fuel cell or fuel-cell hybrid vehicles; battery-electric vehicles; and electric
include total life-cycle costs per fleet, total life-cycle costs per vehicle,
average annual vehicle costs per vehicle, and average costs per mile. Graphical outputs are detailed by expense
categories for each vehicle (capital costs, operator costs, overhaul costs,
maintenance costs, fuel costs and depot costs) and include separate graphs for
costs per mile, total lifecycle costs, average annual costs, and percent
distribution of total costs among the different expense categories.
This model was developed for the U.S.
Department of Transportation Research and Innovative Technology Administration
and the Federal Transit Administration by M.J. Bradley & Associates.
This Life Cycle Cost Model contains sixteen
worksheets. There are six data input worksheets (labeled I1 I6), four output
worksheets for the results of the calculations (labeled O1 O4), and four
output graphs which graphically summarize the results (labeled G1-G4). When running the model all of these
worksheets may be printed to document the results. The model also includes two
interim calculation worksheets (worksheets C1 and C2) that are not meant to be viewed
The user should input
all life cycle cost assumptions in the YELLOW BOXES on worksheets I1 I6. All results of the annual operating cost,
capital cost, overhaul cost, and life cycle cost calculations can be viewed on
worksheets O1 O4 and G1 G4.
not make any changes to worksheets O1 O4 or C1 C2.
Worksheet I1 - DEPOT BASELINE
This worksheet is used
to input assumptions about the number of vehicles, assigned personnel, the
fuels used by the different vehicle types to be analyzed, and to input financial
to five fuels can be specified two liquid fuels, two gaseous fuels, and
electricity from the grid.
to two different vehicle/technology types can be specified to operate on each fuel. For example: Liquid Fuel 1 = Diesel, Vehicle types = Diesel and Diesel hybrid; Gaseous
Fuel 1 = Compressed Hydrogen, Vehicle types = Fuel Cell and Fuel Cell Hybrid.
user must input appropriate names for each fuel and for each vehicle/technology
type that will be used by each fuel.
each fuel input the purchase cost of the fuel, in $/gallon for liquid fuels,
$/GJ for gaseous fuels, and $/kwh for electricity. For gaseous fuels the user may also specify a
separate cost of compression, in $/GJ
five fuels do not have to be used data boxes for one or more fuels may be
left blank. All other yellow boxes on the worksheet must be filled in.
Worksheet I2 Vehicle Tech Annual
This worksheet is used
to specify the vehicle/technology types to be analyzed, and to input operating
cost assumptions for each one.
Line 8 choose up to two vehicle/technology types to operate on each fuel, from
the drop-down boxes in Columns F X. The names that appear in the drop-down menu in each column are those
that were input on Worksheet I1 for the different fuels.
each vehicle/technology type chosen, fill in appropriate operating cost
assumptions in the yellow boxes on Lines 10 29 in the appropriate
column. If no vehicle/technology type
is chosen for a particular column leave the cells in that column blank.
this model annual maintenance costs are calculated based on $/mi cost factors,
which are specified for non-propulsion and propulsion-related vehicle
systems. Propulsion-related costs can be
specified separately for the engine/power plant, the transmissions/drive
system, and the fuel system.
this model the costs for brake relines are separated from other non-propulsion
maintenance in order to be able to capture the benefits of hybrid propulsion
system regenerative braking.
model also allows the user to specify up to three different technology-specific
maintenance items separate from the basic $/mi cost factors. For each one the cost factors can be
specified as $/yr, $/mi, or labor hr/yr.
user must also specify the in-service fuel economy for each vehicle/technology
type on Line 32. For liquid fuels the fuel
economy should be specified as miles per gallon (MPG). For gaseous fuels the fuel economy should be
specified as miles per diesel-equivalent gallon (MPDEG). One diesel-equivalent gallon contains 128,400
btu or 0.1355 GJ of energy (i.e. 1 MPDEG = 7.38 mi/GJ; 1 mi/GJ = 0.1355 MPDEG)
any vehicle that will derive some or all of its energy from the electric grid,
the vehicle's electricity use should be input on Line 37. Electricity use should be input as
kilowatt-hours per mile (kwh/mi). If a
vehicle is a plug-in hybrid the user should specify both the fuel economy on
the liquid of gaseous fuel (MPG or MPDEG) and the amount of electricity drawn
from the grid (kwh/mi).
Worksheet I3 - Vehicle Tech
worksheet is used to specify the purchase cost of each vehicle/technology type,
as well as the overhaul intervals and costs for various vehicle sub-systems.
price for each vehicle type is input on line 10 in the correct column. On line 11 the user can also input the value
of any local, state, or federal credits for the purchase of a particular vehicle/technology
type. If a value is input on line 11 the
model will use the net purchase cost (line 12) in life cycle cost calculations.
lines 14 19 the user must input appropriate costs and intervals for overhaul
of the vehicle' engine/powerplant, transmission/drive system, and base vehicle
(non-propulsion systems). The user may
also specify up to three technology-specific overhaul items on lines 20
25. These lines might be used to
highlight items such as hybrid battery system replacements. For each overhaul category the interval
between overhauls can be specified as miles operated or hours
operated. Hours operated is calculated
by the model as: miles operated
average speed (i.e. 30,000 mi/yr 12 mph = 2,500 hr/yr).
the interval assumptions input by the user, and annual mileage and average
speed assumptions input on worksheet I2, the model will place overhaul costs in
the correct years throughout the useful life of each vehicle/technology type.
THE MODEL ASSUMES THAT OVERHAUL INTERVALS INPUT ON Worksheet I3 ARE CONSTANT
THROUGHOUT A VEHICLE' LIFE. It also
assumes that overhaul costs are constant (except for defined inflation). If overhaul intervals or costs for any vehicle
sub-system will vary over time leave the relevant boxes on worksheet I3 blank
and input variable overhaul costs on worksheet I4. For example, fuel cell technology is still
maturing and one might assume that the cost of fuel cell powerplant overhauls
(i.e. fuel cell stack replacement) will actually decrease for successive
overhauls on any particular vehicle. If
so one would leave line 14 and 15 blank in the Fuel Cell vehicle column, and
input the costs of fuel cell stack replacements on worksheet I4.
Worksheet I4 - Variable Overhaul Intervals
worksheet is used to input assumptions about overhaul costs for sub-systems for
which the cost of the overhauls and/or the overhaul interval will vary
throughout a vehicle' life.
the TOTAL OVERHAUL COSTS for systems with variable costs/intervals on the
appropriate lines representing each year in a vehicle' life. Note the accumulated miles and hours at the
end of each year, as a guide for when overhauls are required.
entered in each year should represent INFLATED DOLLAR values. When calculating total costs the model will
not apply any inflation to the values entered on worksheet I4.
NOT INCLUDE in the values entered any costs related to overhaul of vehicle
sub-systems for which intervals and costs are defined on worksheet I3, lines 14
Worksheet I5 - Infrastructure
worksheet is used to define the purchase cost and annual operating and maintenance
cost of infrastructure investments required for each vehicle/technology type.
each type of infrastructure investment the user must define a useful life
(years). In many cases this useful life
will be longer than the useful life of the vehicles being analyzed. The model will amortize each infrastructure
investment over its defined useful life.
Worksheet I6 - Training
worksheet is used to define the initial and annual training requirements
applicable to each vehicle/technology type.
each employee type (vehicle operator, vehicle mechanic, manager) the user must
input the number of hours of training required per employee. The model will use
the number of employees and the hourly labor rates input on worksheets I1 and
I2 to calculate total initial and annual training costs.
Results: Worksheets O1 O4, G1 G4
model uses all of the assumptions input by the user on worksheets I1 – I6 to
calculate First Year Annual Operating Costs, Total Capital Costs, Overhaul
Costs, and Total Life Cycle Costs.
This data is displayed in tabular form on worksheets:
and graphically in worksheets: