Appendix A

Appendix A

Excel

About This Life Cycle Cost Model

This Lifecycle 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.

Elements 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.

The 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.

The 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.

Some 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.

The 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.

Some 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 trolleys.

Outputs 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.

Instructions

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 or printed.

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.

Do not make any changes to worksheets O1 O4 or C1 C2.

Worksheet I1 - DEPOT BASELINE

Graphic Version

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 assumptions.

  • Up to five fuels can be specified two liquid fuels, two gaseous fuels, and electricity from the grid.
  • Up 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.
  • The user must input appropriate names for each fuel and for each vehicle/technology type that will be used by each fuel.
  • For 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
  • All 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

Graphic Version

This worksheet is used to specify the vehicle/technology types to be analyzed, and to input operating cost assumptions for each one.

  • On 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.
  • For 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.
  • In 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.
  • In 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.
  • The 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.
  • The 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)
  • For 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 Capital

Graphic Version

This 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.

  • Purchase 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.
  • On 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).
  • Using 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

Graphic Version

This 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.

  • Input 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.
  • Values 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.
  • DO 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 25.

Worksheet I5 - Infrastructure

Graphic Version

This worksheet is used to define the purchase cost and annual operating and maintenance cost of infrastructure investments required for each vehicle/technology type.

  • For 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

Graphic Version

This worksheet is used to define the initial and annual training requirements applicable to each vehicle/technology type.

  • For 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

The 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: