# Presentation: 040125

## Fuel Cell Bus Life Cycle Cost Model

| U.S. Department 
of Transportation |
| --- |
|  |

- Current Base Case & Future Cost Scenarios

## Outline

- Life Cycle Cost Model
- What is included?
- Required Inputs (assumptions)
- Format of Results
- Sources for “Base Case” Assumptions
- Base Case Results
- “Best Case” Future Cost Scenario

## Project Overview

-     This analysis was conducted using a spread-sheet based Life Cycle Cost Model developed for the Volpe National Transportation Systems Center by M.J. Bradley & Associates.   The model is designed to allow side-by-side analysis of multiple bus/technology types that operate on a range of liquid and gaseous fuels.  The model will support on-going fuel cell bus work at the Department of Transportation.

## Life Cycle Cost Model

- Developed specifically for this project
- Designed to be flexible
- Can analyze multiple liquid & gaseous fuels
- All major cost assumptions can be modified by user
- Can analyze buses with different useful lives
- Technology-specific cost elements included
- Up to 8 bus/technology types can be analyzed side-by-side

## Included Cost Elements

- Capital Costs:
- Bus purchase
- Infrastructure (fuel station, depot modifications, special tools)
- Annual Operating costs:
- Bus operator labor
- Bus maintenance
- Periodic bus overhaul
- Training
- Fuel station/depot systems O&M

## Spread Sheet Tool

- Six Input worksheets for required assumptions
-    -  Number of buses
-    -  Labor rates
-    -  Bus purchase costs, etc

- Four output worksheets for results of calculations
-    -  First year operating costs
-    -  Capital costs
-    -  Overhaul Costs
-    -  NPV of total life cycle costs

## Graphical Results

## Required Inputs

## Fuel Cell Bus “Base Case”

- Intended to evaluate current costs for Fuel Cell buses compared to other bus propulsion options
- Fuel cell technology is in its infancy while other technologies are mature (diesel, CNG) and maturing (hybrid)
- Five bus/technology options were analyzed, which use three different fuels
- Diesel Fuel:     Diesel & Diesel Hybrid buses
- Natural Gas:    CNG buses
- Hydrogen:        Fuel Cell & Fuel Cell Hybrid buses
- For all technologies, the base vehicle is assumed to be a 40-ft urban transit bus

## Technology Details

|  | 
Diesel | Diesel Hybrid | 
CNG | 
Fuel Cell | Fuel Cell Hybrid |
| --- | --- | --- | --- | --- | --- |
| Power Plant | Diesel Engine | Diesel 
Engine | Natural Gas Engine | PEM Fuel Cell Engine | PEM Fuel Cell Engine |
| 
Drive System | 
5-speed automatic transmission | Generator
Electric motor
Power electronics 
Energy storage  | 
5-speed automatic transmission | 
Electric motor 
Power electronics
 | 
Electric motor
Power electronics
Energy storage |
| Fuel System | 
Diesel tank | 
Diesel tank | 3,600 psi CNG storage | 5,000 psi
C-H2 Storage | 5,000 psi
C-H2 Storage |

- All other bus systems assumed to be the same for all bus types

## Sources of Base Case Assumptions

| SOURCE | ASSUMPTIONS |
| --- | --- |
| USDOT National Transit Database | Annual Bus Mileage
Average in-service speed
Average in-service Fuel Economy (Diesel, CNG) |
| USDOE Clean Cities Alternative Fuels Price Report (Mar 2007) | Diesel Fuel cost
CNG fuel cost |
| 2006 APTA Transit Vehicle Database | Bus Purchase costs (Diesel, CNG, Diesel Hybrid) |
| 30-yr T-Bill & TIPS Yields | Discount rate
Annual inflation rate |
| USDOE Transit Costs 1.0 Model | CNG fuel station & depot infrastructure costs |
| NREL Advanced Vehicle Testing Activity reports
 - 1 Fuel Cell bus report
 - 2 Fuel Cell Hybrid bus reports
 - 2 Natural Gas bus reports
 - 2 Diesel Hybrid bus reports | $/mi maintenance costs (all bus types)
Hydrogen fuel cost
Fuel Cell & Fuel Cell Hybrid bus purchase cost
Hydrogen fuel station purchase costs
Fuel Cell & Fuel Cell Hybrid bus fuel economy |
| Manufacturer literature/discussion with transit maintenance managers | Overhaul costs
Overhaul intervals |

## NREL Data – Fuel Cell Buses

## NREL Data – NG & Hybrid Buses

## Major Base Case Assumptions

|  |  
Diesel | Diesel Hybrid |  |  | 
CNG | Fuel Cell | FC
Hybrid |
| --- | --- | --- | --- | --- | --- | --- | --- |
| Number of Buses | 100 |  |  |  |  |  |  |
| Useful Life | 12 years |  |  |  |  |  |  |
| Annual Mileage | 32,600 |  |  |  |  |  |  |
| Average Speed | 12.4 MPH |  |  |  |  |  |  |
| Labor Cost | $50/hr |  |  |  |  |  |  |
| Fuel Costs | Diesel = $2.63/gal     CNG = $2.17/DEG     H2 = $6.70/kg |  |  |  |  |  |  |
| Maintenance ($/mi) | $0.55 |  | $0.56 | $0.56 |  | $1.40 | $1.40 |
| Fuel Economy (MPDEG) | 3.2 |  | 4.0 | 2.4 |  | 2.8 | 5.1 |
| Bus Purchase | $327,000 |  | $502,000 | $377,000 |  | $3.2 mill | $3.2 mill |
| Fuel Station Purchase | $180,000 |  | $180,000 | $1.8 mill |  | $3.5-$7.0 mill | $1.7-$4.0 mill |
| Other Infrastructure | $0 |  | $45,000 | $450,000 |  | $875,000 | $895,000 |

## Hydrogen Fuel Station Costs

- Published sources used for projections

## Base Case – First Year Costs

**PER BUS COSTS**

**ADDITIONAL DEPOT COSTS**

## Base Case – Capital Costs

## Base Case – Total Life Cycle $/mi

## Base Case – Local* Life Cycle $/mi

- * Does not include the portion of capital costs paid with federal funds

## Base Case – Total Life Cycle $/bus

## Base Case – Cost Distribution

**TOTAL LIFE CYCLE COSTS**

**LOCAL LIFE CYCLE COSTS**

- The distribution of costs for CNG and Diesel Hybrid buses is similar to Diesel buses

## Base Case Summary

- Total Life Cycle Costs for Fuel Cell buses are currently 3 times higher than costs for Diesel, CNG, and Diesel Hybrid buses
- If only local costs are included, current fuel cell buses still cost 60-90% more per mile to operate than Diesel buses
- All cost elements are higher for Fuel Cell buses
- Capital costs 10x higher
- Overhaul costs 3x higher
- Annual Maintenance costs 2x higher
- Fuel Costs 2 -3 x higher
- Capital amortization accounts for 15% of total costs with Diesel buses, but over 50% with Fuel Cell buses

## Near Term Future Costs – “Best Case” 

- The “Best Case” Scenario is based on meeting FTA’s near-term National Fuel Cell Bus performance objectives...
- Bus Purchase Cost ≤ 5x Diesel bus = $1.6 mill
- Fuel Cell stack durability 20,000 - 30,000 hrs
- Double fuel economy of Diesel bus = 6.4 MPDEG
-        ... and DOE’s 2015 goal for hydrogen cost
- <$3/kg (untaxed) in 2005 dollars = $3.39/DEG

## Other “Best Case” Assumptions

- To meet fuel economy goal, assume that Fuel Cell buses must use hybrid propulsion
- Other Major assumptions:
-  $/mi propulsion maintenance costs ≤ 2x Diesel
-             = $0.20 - $0.40/mi
- Hydrogen fuel station cost ≤ 2x cost of similar capacity CNG station
-             = $1.8 mill (for station approx 1⁄2 size of CNG station)
- Fuel cell stack replacement cost 1⁄2 of base case cost
-             = $50,000
- Hybrid battery replacement cost 2/3 of base case cost
-             =$20,000

## Best Case – Total Life Cycle $/mi

## Best Case – Local* Life Cycle $/mi

- * Does not include the portion of capital costs paid with federal funds

## Best Case – Total Life Cycle $/bus

## Best Case – Local* Life Cycle $/bus

- * Does not include the portion of capital costs paid with federal funds

## Effect of Hydrogen Price

## Best Case Summary

- Under the “Best Case” near-term scenario, if all FTA and DOE cost targets are met, total life cycle costs for Fuel Cell Hybrid buses fall by 40% compared to the base case, but
- Total per-mile costs will still be $3.30/mi more than total costs for Diesel buses
- Local per-mile costs will still be $0.58/mi more than local costs for Diesel buses
- Under the Best Case scenario the greatest contributor to increased life cycle costs for Fuel Cell Hybrid buses is still the bus purchase price

## Best Case Summary (cont.)

- With all other best case assumptions held constant the purchase price of a Fuel Cell Hybrid bus would have to fall significantly for life cycle costs to match those of a diesel bus:
- $500,000/bus to match diesel local life cycle costs (~ equivalent to current Hybrid Diesel bus price)
- $350,000/bus to match diesel total life cycle costs (less than the price of a current CNG bus)
- Even if hydrogen fuel was free, life time fuel cost savings from a Fuel Cell Hybrid bus would not exceed the Best Case assumed bus purchase price premium compared to Diesel buses