A national laboratory of the U.S. Department of Energy

Office of Energy Efficiency & Renewable Energy

National Renewable Energy Laboratory 

Innovation for Our Energy Future 

Santa Clara Valley Transportation 

Authority and San Mateo County 

Transit District 

Fuel Cell Transit Buses: 

Evaluation Results

Kevin Chandler 

Battelle 

Leslie Eudy 

National Renewable Energy Laboratory 

Technical Report 

NREL/TP-560-40615 

November 2006 

NREL is operated by Midwest Research Institute ● Battelle Contract No. DE-AC36-99-GO10337 
Santa Clara Valley 

Transportation Authority and 

San Mateo County Transit 

District 

Fuel Cell Transit Buses: 

Evaluation Results

Kevin Chandler 

Battelle 

Leslie Eudy 

National Renewable Energy Laboratory 

Prepared under Task No. HF65.8200 

Technical Report 

NREL/TP-560-40615 

November 2006 

National Renewable Energy Laboratory

1617 Cole Boulevard, Golden, Colorado 80401-3393 

303-275-3000 • www.nrel.gov 

Operated for the U.S. Department of Energy 

Office of Energy Efficiency and Renewable Energy 

by Midwest Research Institute • Battelle 

Contract No. DE-AC36-99-GO10337
NOTICE

This report was prepared as an account of work sponsored by an agency of the United States government. 

Neither the United States government nor any agency thereof, nor any of their employees, makes any 

warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or 

usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not 

infringe privately owned rights. Reference herein to any specific commercial product, process, or service by 

trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, 

recommendation, or favoring by the United States government or any agency thereof. The views and 

opinions of authors expressed herein do not necessarily state or reflect those of the United States 

government or any agency thereof. 

Available electronically at http://www.osti.gov/bridge

Available for a processing fee to U.S. Department of Energy 

and its contractors, in paper, from: 

U.S. Department of Energy 

Office of Scientific and Technical Information 

P.O. Box 62 

Oak Ridge, TN 37831-0062 

phone: 865.576.8401 

fax: 865.576.5728 

email: mailto:reports@adonis.osti.gov

Available for sale to the public, in paper, from: 

U.S. Department of Commerce 

National Technical Information Service 

5285 Port Royal Road 

Springfield, VA 22161 

phone: 800.553.6847 

fax: 703.605.6900 

email: orders@ntis.fedworld.gov

online ordering: http://www.ntis.gov/ordering.htm

Printed on paper containing at least 50% wastepaper, including 20% postconsumer waste
Acknowledgements 

This evaluation at Santa Clara Valley Transportation Authority (VTA) and San Mateo County 

Transit District (SamTrans) would not have been possible without the support and cooperation of 

many people. The authors thank the following: 

U.S. Department of Energy 

Sigmund Gronich 

John Garbak 

National Renewable Energy Laboratory 

Keith Wipke 

George Sverdrup 

Santa Clara Valley Transportation Authority 

Art Douwes 

Jerry Oxsen 

Sharon McElligott 

Ephraim Cadaing 

Bill Wilson 

Pat Smith 

Steve Maloon 

Jeff Flagg 

Cynthia Shephard 

Dwight Barnes 

Jim Wilhelm 

Craig Ferguson 

Charles Brown 

John Blase 

Kendall Whitson 

San Mateo County Transit District 

David Olmeda 

Ken Quijano 

Ballard Power Systems, Inc. 

Byron Somerville 

Bill Taylor 

TJ Lawy 

Gillig Corporation 

Chuck Koske 

Air Products and Chemicals, Inc. 

Steve Hoffman 

iii
Table of Contents 

Executive Summary........................................................................................................................ 1 

Infrastructure and Facilities ........................................................................................................ 1 

Early Experience......................................................................................................................... 3 

Evaluation Results ...................................................................................................................... 3 

What’s Next for the Demonstration? .......................................................................................... 6 

Overview......................................................................................................................................... 7 

Project Design and Data Collection............................................................................................ 8 

What Are Fuel Cells and Why Use Them in Transit Buses?...................................................... 9 

Zero Emissions Buses in California.......................................................................................... 10 

Host Site Profile........................................................................................................................ 12 

VTA/SamTrans ZEB Program.................................................................................................. 13 

Ballard Fuel Cell Development and Testing................................................................................. 17 

Infrastructure and Facilities .......................................................................................................... 21 

Compressed Hydrogen Dispensing Station .............................................................................. 21 

Hydrogen Bus Maintenance Facility ........................................................................................ 30 

Fuel Cell and Diesel Bus Descriptions ......................................................................................... 32 

VTA Fuel Cell Bus Operation .................................................................................................. 33 

Early Experience with VTA’s Fuel Cell Buses ........................................................................ 35 

Evaluation Results ........................................................................................................................ 40 

Route Descriptions.................................................................................................................... 40 

Bus Use and Availability .......................................................................................................... 41 

Fuel Economy and Cost............................................................................................................ 44 

Maintenance Analysis............................................................................................................... 45 

Roadcall Analysis ..................................................................................................................... 50 

Demonstration Achievements and Challenges ............................................................................. 52 

Achievements............................................................................................................................ 52 

Challenges................................................................................................................................. 53 

What’s Next for this Demonstration? ........................................................................................... 55 

Contacts......................................................................................................................................... 56 

Acronyms and Abbreviations ....................................................................................................... 58 

References and Related Reports ................................................................................................... 59 

Appendix: Fleet Summary Statistics............................................................................................. 62 

iv
Executive Summary 

This report provides evaluation results for prototype fuel cell transit buses operating at Santa 

Clara Valley Transportation Authority (VTA) in San Jose, California. San Mateo County Transit 

District (SamTrans) in San Carlos, California, is a partner with VTA in this fuel cell bus 

demonstration. VTA has been operating three fuel cell transit buses in extra revenue service 

since February 28, 2005. This report provides descriptions of the equipment used (buses and 

infrastructure), early experiences, and evaluation results from the operation of the buses and 

supporting hydrogen infrastructure from March 2005 through July 2006 (17 months). 

This evaluation of prototype fuel cell transit buses at VTA is a part of the U.S. Department of 

Energy’s (DOE) Hydrogen, Fuel Cells & Infrastructure Technologies Program, which integrates 

activities in hydrogen production, storage, and delivery with transportation and stationary fuel 

cell applications. 

VTA and SamTrans began planning their zero-emission bus (ZEB) demonstration in 2000. VTA 

is the lead agency in the operation of these buses; SamTrans shares in the demonstration’s 

planning and operation as well as the capital and operating costs. The goals of this 

demonstration project are to: 

• Determine the status of fuel cell technology in transit applications 

• Identify issues and challenges to overcome 

• Provide community outreach and educate the public on fuel cell and hydrogen 

technology. 

These low-floor fuel cell buses at VTA were built by Gillig with Ballard fuel cell propulsion 

systems and are considered prototype technology. The analysis in this report reflects the 

prototype status of these vehicles. There is no intent to consider the implementation of these 

fuel cell buses as commercial (or full revenue transit service). The evaluation focuses on 

documenting progress and opportunities for improving the vehicles, infrastructure, and 

procedures. 

Infrastructure and Facilities 

VTA has three bus operation depots: Cerone, Chaboya, and 

North. The Cerone operating division was selected as the 

home of the ZEB program primarily because of space 

availability. The infrastructure and facilities added for fuel 

cell bus operations at Cerone included a compressed 

hydrogen dispensing station, a stand-alone two-bay maintenance facility, and an upgraded bus 

wash to accommodate the taller fuel cell buses (Figure ES-1). 

The hydrogen dispensing station is leased from Air Products and Chemicals, Inc. (Air Products) 

with a three-year contract and an option for two additional years. The installation of the 

equipment was completed in May 2004; however, actual dispensing of hydrogen at the station 

did not start until November 2004. VTA also provided the concrete pad/foundation for the 

 1
station and performed additional work for the utility connections and other activities for the 

station at an additional cost. During initial use of the hydrogen fueling infrastructure, there were 

some significant challenges that had to be overcome. The process of building, permitting, and 

commissioning the station took longer than expected due in part to a general lack of experience 

and precedence with this application of hydrogen in the San Jose area as well as typical startup 

issues for a new fueling technology. 

Figure ES-1. Compressed hydrogen dispensing station, fuel cell bus, 

bus wash, and maintenance facility 

A separate maintenance facility was designed and built for the fuel cell bus demonstration. The 

two-bay building houses the equipment and some of the spare parts needed to maintain and 

repair fuel cell buses. This facility was designed for hydrogen requirements and, like the fueling 

station, the maintenance building is equipped with the necessary devices to enable safe operation 

and maintenance on hydrogen vehicles. This facility opened for operation in November 2005. 

Delays in completion of the building were caused by issues similar to those of the hydrogen 

dispensing station. These included issues of building codes and familiarity with hydrogen. The 

new bus wash was also designed and constructed to allow for the added height of the fuel cell 

buses and the hydrogen fuel on board the buses. The total cost for these three facilities—

designed to meet the operating requirements for the VTA hydrogen fuel cell buses—was $4.4 

million. 

The method for dispensing compressed hydrogen from the station into the buses has progressed. 

Until April 2005, it took approximately 18-24 minutes to fuel a fuel cell bus. Since April 2005, 

fueling time has been reduced to an average of 10-14 minutes. The hydrogen dispensing station 

has had 31,836 kg of liquid hydrogen delivered to it, and the station has delivered 14,024 kg of 

compressed hydrogen to the fuel cell buses. This station has delivered approximately 460 

fuelings at an average of 16 minutes/fill, 30.9 kg/fill, and 1.93 kg/min. 

 2
The hydrogen dispensing station was built to the original specifications to support a minimum of 

six fuel cell buses. This is double the current fleet size. If the station utilization is not high 

enough to overcome the liquid hydrogen storage tank boil-off rate, the tank will vent this 

hydrogen. The size of the station caused the loss of approximately 50% of the hydrogen fuel 

during this demonstration. Air Products reports that if the station throughput had been greater, 

the hydrogen losses would have been significantly reduced. 

Hydrogen fuel cost an average of $9.06 per kg throughout the evaluation period (March 2005 

through July 2006). This high cost is an indicator of the low volume use of hydrogen as a fuel. 

With the boil off of hydrogen taken into account, this cost would be double. Diesel fuel 

averaged $2.07 per gallon during the same evaluation period. 

Early Experience 

Familiarization training for hydrogen safety and general characteristics was a high priority for 

the fleet. Held at VTA, this training included all staff at Cerone as well as local emergency 

responders (fire and police). The two VTA mechanics assigned to the fuel cell buses also 

received training from Ballard on the fuel cell propulsion system and training from Air Products 

on the operation of the hydrogen dispensing station. The bus drivers were trained on the fuel cell 

vehicle systems and other items on the pre-trip inspection sheet. VTA continues to provide 

familiarization training for emergency responders. An emergency response card was prepared to 

provide emergency responders with a quick reference regarding the locations of fuel tanks, shutdown devices, high voltage lines, and other devices that would assist them in an emergency. 

VTA also accommodates requests for tours and brings the buses to events as time and resources 

allow. 

VTA controls which drivers are assigned to operate the fuel cell buses rather than train all drivers 

at Cerone. The number of trained drivers started at two and is now beyond 20. Comments from 

the VTA drivers and staff have been positive. To ensure safety, use of the hydrogen dispensing 

station is restricted to trained personnel including two VTA fuel cell bus mechanics, Ballard’s 

onsite mechanic, and Air Products’ staff. 

Evaluation Results 

VTA purchased three Gillig Corporation buses featuring fuel cell propulsion systems by Ballard 

Power Systems at a cost of $10.6 million ($3.5 million each)—a price that includes a two-year 

warranty, parts, training, and support from Gillig and Ballard. 

The evaluation results include both fuel cell (three buses) and diesel baseline (five buses) study 

groups of buses. Both bus groups are Gillig low-floor buses. The fuel cell buses are slightly 

newer than the diesel buses. The fuel cell buses are also 24 inches taller than the diesel buses, 

which caused some concerns about clearance. Additionally, the fuel cell buses are 6,800 lb 

heavier than the diesel buses. This restricted the maximum number of passengers to include all 

seats and five standees in the fuel cell buses (compared to all seats and 43 standees in the diesel 

buses). The fuel cell buses do not have a hybridized system and therefore do not have 

regenerative braking or additional energy storage. 

 3
VTA Routes—VTA operates 71 fixed bus routes, 11 of which are express service. Additionally, 

VTA operates one bus rapid transit line and 14 shuttle service routes. The weekly average bus 

speed at Cerone is 14.5 mph. All standard buses at Cerone are randomly dispatched on routes. 

For demonstrating this advanced technology, the fleet chose to use the three fuel cell buses as 

“extra” service on existing routes, meaning they are placed on routes between two regularly 

scheduled buses. The intent is to prevent passengers from being stranded for a long time in the 

event of a failure. Two fuel cell buses are operated during peak weekday hours with one 

available as a spare. VTA limits the use of the buses to times when a trained fuel cell bus 

mechanic is available. 

Bus Use and Availability—Bus use and availability are indicators of reliability. The lack of bus 

usage may indicate downtime for maintenance, repair, or purposeful reduction of planned work 

for the buses. Figure ES-2 shows mileage and fuel cell system operating hour accumulation 

from the start of hydrogen fueling in November 2004 through July 2006. As expected, usage 

accumulated faster after the buses went into revenue service at the end of February 2005. Usage 

of the fuel cell buses has been limited by running the buses only on weekdays for extra service as 

well as by maintenance issues and the availability of specially trained drivers and mechanics. 

0

10,000

20,000

30,000

40,000

50,000

60,000

Nov-04

Dec-04

Jan-05

Feb-05

Mar-05

Apr-05

May-05

Jun-05

Jul-05

Aug-05

Sep-05

Oct-05

Nov-05

Dec-05

Jan-06

Feb-06

Mar-06

Apr-06

May-06

Jun-06

Jul-06

Miles

0

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

FC Hours

Cumulative Miles Cumulative Fuel Cell Hours

Figure ES-2. Cumulative mileage and fuel cell hours for three fuel cell buses 

During the 17-month evaluation period, the three buses accumulated 40,429 miles and 3,219 

hours on the fuel cell systems. Average monthly mileage per fuel cell bus was 809 miles. The 

diesel study buses were operated in normal VTA service from Cerone and included weekend 

operation. The average monthly mileage per diesel bus during the evaluation period was 4,335 

miles (over five times higher than the FCBs). 

 4
Availability of a diesel bus was measured by the number of days it might be scheduled for 

service and the number of days it was unavailable for service due to maintenance issues. During 

the evaluation period, the diesel buses had an availability rate of 85%. VTA’s goal is 80% for 

diesel buses. During the evaluation period, the fuel cell buses had an average availability rate of 

58% for each weekday. VTA’s fuel cell bus schedule was designed for two of the three fuel cell 

buses to be in service on weekdays, except holidays. Based on VTA’s planned usage of the fuel 

cell buses, the availability goal was 67%. 

Fuel Economy—During the evaluation period, the fuel cell buses averaged 3.12 miles per kg of 

hydrogen, which translates into 3.52 miles per diesel equivalent gallons (or miles per gallon—

mpg). This fuel economy includes all hydrogen fuel added to the buses even if there was some 

venting for maintenance or testing during the evaluation period. The diesel study group had a 

fuel economy of 3.98 mpg. With the diesel buses as the baseline, the fuel cell buses had a fuel 

economy 12% lower on an energy equivalent basis. Note that the electric propulsion design of 

the fuel cell buses does not include regenerative braking. Figure ES-3 shows the monthly 

average fuel economies of the fuel cell and diesel buses. 

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

4.50

Mar-05

Apr-05

May-05

Jun-05

Jul-05

Aug-05

Sep-05

Oct-05

Nov-05

Dec-05

Jan-06

Feb-06

Mar-06

Apr-06

May-06

Jun-06

Jul-06

Miles per Gallon (Diesel Equivalent)

Fuel Cell Bus Diesel Bus

Figure ES-3. Average fuel economy (mpg) by month 

Maintenance Costs—The maintenance costs in this report pertain to only the evaluation period 

(March 2005 through July 2006) for the two study groups of buses. All work orders for the 

study buses were collected and analyzed for this evaluation. For this analysis, the labor rate for 

maintenance was set at a constant $50 per hour; this is not reflective of an average rate at VTA. 

Total maintenance costs were $3.55 per mile for the fuel cell buses and $0.54 per mile for the 

diesel buses. The total maintenance costs are much lower for the diesel buses compared to the 

fuel cell buses. This reflects the fact that the fuel cell buses are in the prototype development 

 5
stage for transit bus service, which caused a need for significant mechanic labor for 

troubleshooting. 

Warranty costs were collected but not accounted for in the cost-per-mile calculations. The fuel 

cell buses had nearly $540,000 in warranty parts replaced during the evaluation period (March 

2005 through July 2006). 

The propulsion-related vehicle systems in the buses include the exhaust, fuel, engine, electric 

propulsion, air intake, cooling, non-lighting electrical, and transmission systems. The fuel cell 

buses ($2.37 per mile) had significantly higher propulsion-related maintenance costs than the 

diesel buses ($0.20 per mile) for all these systems, except exhaust and transmission. 

Roadcalls—A roadcall (RC) is defined as a failure of an in-service bus that causes the bus to be 

replaced on route or a significant delay in schedule. If the problem with the bus can be repaired 

during a layover and the schedule is kept, it is not considered a RC. The analysis provided in 

this report includes RCs caused by “chargeable” failures. Chargeable RCs include problems 

with systems that can physically disable the bus from operating on route, such as interlocks 

(doors), engine, etc. They do not include problems with radios, destination signs, etc. The fuel 

cell buses had 898 miles between roadcalls (MBRC) for all roadcalls and 918 MBRC for 

propulsion-related roadcalls. The diesel buses had 8,189 MBRC for all roadcalls and 10,838 

MBRC for propulsion-related roadcalls. 

What’s Next for This Demonstration? 

This report covers VTA operation of the fuel cell buses through July 2006. This is the end of the 

two-year demonstration and the warranty/support period for the fuel cell buses, as defined by 

Ballard. VTA has continued to run the fuel cell buses beyond July 2006 and is paying for 

support by Ballard and parts on a month-to-month basis. VTA currently intends to attempt 

another full year of service; however, additional funding and level of support from Ballard and 

Air Products have not yet been finalized. 

There are ongoing discussions between VTA and Ballard to potentially upgrade the existing fuel 

cell buses to a hybrid propulsion system and Ballard’s newer model fuel cell modules. Issues yet 

to be resolved in these discussions include funding requirements and sources as well as 

expectations and design of operations for these new hybrid fuel cell buses. 

VTA’s current lease of the hydrogen fuel dispensing station runs through May 2007 with two 

one-year options available from Air Products. Continuation beyond this would require 

renegotiation of the lease rates with Air Products. Air Products indicates that it intends to 

support that station and continue its testing and development activities. 

Ballard intends to continue to be a supplier of fuel cell power plants to vehicle manufacturers. It 

also has a new model fuel cell module for transportation applications. Ballard’s plans are to 

have a potentially commercial fuel cell module product for the 2010-2015 timeframe. 

 6
Overview 

This report provides results from an evaluation of prototype fuel cell transit buses operating at 

Santa Clara Valley Transportation Authority (VTA) in San Jose, California. San Mateo County 

Transit District (SamTrans) in San Carlos, California, is a partner with VTA in this fuel cell bus 

demonstration. VTA has been operating three fuel cell transit buses in extra revenue service 

since February 28, 2005. This report describes the equipment used (buses and infrastructure) and 

provides early experience details, lessons learned, and results from the operation of the buses and 

supporting hydrogen fuel station through July 31, 2006 (evaluation period of 17 months). 

This evaluation is part of DOE’s Hydrogen, Fuel Cells & Infrastructure Technologies (HFCIT) 

Program, which integrates activities in hydrogen production, storage, and delivery with 

transportation and stationary fuel cell applications. DOE’s National Renewable Energy 

Laboratory (NREL) works with fleets and industry groups to test advanced technology, heavyduty vehicles in service and provides unbiased information resources for fleet managers 

considering these technologies. Information collected during vehicle performance and operation 

evaluations is fed back to research programs to help shape future work. 

In early 2003, DOE initiated the Controlled Hydrogen Fleet and Infrastructure Demonstration 

and Validation Project, which focuses on light-duty fuel cell vehicles and supporting 

infrastructure. The purpose of the project is to examine the impact and performance of fuel cell 

vehicles and supporting hydrogen infrastructure in real-world applications. The data collected 

and analyzed during this “learning demonstration” will be used to verify performance targets to 

assess technology readiness. To coordinate efforts, the fuel cell bus evaluation team is working 

closely with the light-duty demonstration project teams. The overall goal is to collect similar 

data for heavy-duty fuel cell vehicles that will enable a more complete picture of fuel cell 

performance over a wide range of vehicle applications. 

In addition to the light-duty demonstration project, DOE and NREL are also working with the 

Federal Transit Administration (FTA), an agency of the U.S. Department of Transportation, and 

heavy vehicle operators (mostly transit agencies) to demonstrate heavy fuel cell and hydrogen 

vehicles to collect operations experience data. This data collection and evaluation follows the 

DOE/NREL standardized evaluation protocol1

. A customized version of the General Evaluation 

Plan was created for fuel cell bus evaluations and is described in the draft Fuel Cell Transit Bus 

Evaluation Protocol, June 2005. Current heavy fuel cell vehicle evaluation sites are shown in 

Table 1. More information is available at 

www.eere.energy.gov/hydrogenandfuelcells/tech_validation/ca_transit_agencies.html. 

This data report examines evaluation results from the three prototype fuel cell buses and five 

diesel baseline buses operating from the same VTA bus depot. The evaluation period presented 

in this report is March 2005 through July 2006—17 months of operation. 

 

1

 General Evaluation Plan, Fleet Test & Evaluation Projects, July 2002, NREL/BR-540-32392, 

www.nrel.gov/vehiclesandfuels/fleettest/pdfs/32392.pdf. 

 7
Table 1. DOE/NREL Heavy Vehicle Fuel Cell/Hydrogen Evaluations 

Fleet Vehicle/Technology Evaluation Status 

SunLine Transit Agency 

(Thousand Palms, California) 

ISE Corp. ThunderPower hybrid fuel 

cell transit bus (one bus) Complete and reported 

Shuttle bus: Hydrogenics and Enova, 

battery-dominant fuel cell hybrid (one 

bus) 

Shuttle bus in operation, data 

U.S. Air Force/Hickam Air Force Base collection started 

(Honolulu, Hawaii) Delivery van: Hydrogenics and Enova, 

fuel cell hybrid (one van) Van just going into service 

VTA (San Jose, California) and 

SamTrans (San Carlos, California) 

Gillig/Ballard fuel cell transit bus (three 

buses) 

Evaluation complete, data report 

presented here 

Alameda-Contra Costa Transit District 

(AC Transit) and Golden Gate Bridge, 

Highway, and Transportation District 

(Oakland, California) 

Van Hool/UTC fuel cell hybrid transit 

bus integrated by ISE Corp. (three 

buses) 

Evaluation in process, all three 

buses in operation since March 

2006, full service started in April 

2006 

New Flyer ISE Corp. hydrogen internal 

combustion engine transit bus (one 

bus-HHICE) 

HHICE bus in service, data 

collection started SunLine Transit Agency 

(Thousand Palms, California) Van Hool/UTC fuel cell hybrid transit 

bus integrated by ISE Corp. (one busFCB) 

FCB evaluation in process, bus in 

operation since January 2006 

Project Design and Data Collection 

As mentioned earlier, DOE/NREL evaluation projects focus on using a standardized process for 

data collection and analysis, communicating results clearly, and providing an accurate and 

complete evaluation. The objectives of the data collection are to validate fuel cell and hydrogen 

technologies in bus applications to: 

• Determine the status of fuel cell systems for buses and corresponding hydrogen 

infrastructure 

• Provide feedback for DOE HFCIT Program research and development 

• Provide “lessons learned” on implementing next generation fuel cell systems into bus 

operations. 

This evaluation includes prototype fuel cell powered transit buses (40-foot) operating at VTA in 

San Jose, California (bus shown in Figure 1). Five diesel buses were selected from VTA’s 

newest order of Gillig diesel buses operating at the same depot (Cerone). Data have been 

collected in parallel to the three fuel cell buses for the evaluation period starting in March 2005. 

The diesel baseline data were collected and analyzed along side the prototype fuel cell transit 

buses to assess the progress of the fuel cell propulsion development for heavy vehicles and 

specifically in this application at VTA. 

 8
 

Figure 1. Fuel cell transit bus at VTA 

Data for this evaluation were taken from VTA’s data system. Data parameters included: 

• Diesel fuel and engine oil consumption by vehicle and fill 

• Hydrogen fuel consumption by vehicle and fill 

• Mileage data from every vehicle in the study 

• Preventive maintenance action work orders, parts lists, labor records, and related 

documents 

• Records of unscheduled maintenance, including roadcalls and warranty actions by 

vendors (when available in the data system). 

Additional information has been collected on the maintenance/operation experience, issues at the 

hydrogen fueling station and in VTA facilities, and lessons learned at the start-up and during 

operation of the prototype buses. 

What Are Fuel Cells and Why Use Them in Transit Buses? 

A fuel cell is an electrochemical device that uses hydrogen and oxygen to produce electricity. It 

is comprised of two electrodes (cathode and anode) and separated by an electrolyte. Proton 

exchange membrane (PEM) fuel cells are currently most commonly used for vehicle 

applications, because they offer high power density and can operate at low temperatures. There 

are also other promising fuel cell technologies. 

In the operation of a fuel cell, hydrogen is fed to the anode, where a catalyst-coated membrane 

separates the hydrogen electron from the proton. The proton passes through the membrane to the 

cathode side and combines with oxygen to form water. Because the electron cannot pass through 

the membrane, it is forced through an electrical circuit to create electricity. It then flows to the 

cathode where it is reunited with a proton in forming a water molecule. 

A single fuel cell generates a low voltage and must be combined in a series to power applications 

such as transit buses. These fuel cell stacks can consist of hundreds of individual fuel cells. 

Fuel cell propulsion provides an opportunity to reduce emissions from vehicles (and other 

equipment) to zero except for water vapor and some waste hydrogen. Transit bus 

demonstrations have typically been introduction points for new heavy-duty vehicle propulsion 

technologies (i.e., natural gas and hybrid electric). This is because: 

 9
• Transit buses are centrally fueled and maintained. 

• Transit buses are typically operated on fixed routes in urban stop-and-go duty cycles. 

• Transit bus size and weight can easily accommodate new technologies. 

• Capital purchases of transit buses and supporting infrastructure are federally supported 

(80% federal share and other funding programs). 

• Transit buses have high visibility and impact because they operate in densely populated 

areas2. 

During the last 10 years, there have been several fuel cell transit bus demonstrations in the 

United States and Canada. These demonstrations have identified areas of development to 

prepare fuel cell propulsion systems for heavy-duty vehicle service. Examples include: 

• Reducing the size of the fuel cell stack 

• Increasing the power density of the fuel cell stack 

• Reducing the overall weight of the fuel cell and electric propulsion system 

• Developing hydrogen infrastructure for vehicle use 

• Optimizing electric motors and control systems for heavy-duty vehicles 

• Demonstrating that electric propulsion systems are safe for transit vehicles and perform 

well in environmental extremes (high and low temperatures and humidity). 

Table 2 provides a summary of all recent fuel cell transit bus demonstrations in the United 

States, Canada, and Europe. More details on Ballard fuel cell transit bus demonstrations are 

provided later in this report. 

Zero Emissions Buses in California 

In February 2000, the California Air Resources Board (CARB) established a new fleet rule to 

significantly reduce emissions of existing and new transit buses in California. A department of 

the California Environmental Protection Agency, CARB oversees all air pollution control efforts 

in the state. The rule set more stringent emissions standards for new urban bus engines and 

promoted advancement of the cleanest technologies—specifically, zero emission buses (ZEBs). 

The ruling required transit agencies to choose a compliance path—alternative fuel or diesel—for 

meeting emission standards. The selection determined the fuel type for new bus acquisitions 

through model year 2015. The alternative fuel path could include low-emission alternative fuels 

such as compressed or liquefied natural gas, propane, methanol, electricity, fuel cells, or other 

advanced technology (such as gasoline hybrid-electric). 

 

2

 Information excerpted from an FTA presentation at the American Public Transportation Association Bus and 

Paratransit Conference committee meeting in Milwaukee, Wisconsin, May 2003. 

 10
Table 2. Fuel Cell Transit Bus Demonstrations – Overview 

Project 

Dates Status Project Description 

1998 Complete FTA/Georgetown 40-ft FCB operating on methanol using 100 kW PAFC from 

UTC Fuel Cells 

1994-1995 Complete FTA/Georgetown Three 30-foot FCBs operating on methanol using 100 kW 

phosphoric acid fuel cell (PAFC) stacks from Fuji 

1998-2000 Complete Ballard Phase III 

Test program with six 40-foot fuel cell transit buses using 

205 kW PEM fuel cell stacks from Ballard that ran on 

compressed hydrogen; operated three at Chicago Transit 

Authority and three at Coast Mountain Bus (Vancouver) 

2000-2001 Complete Ballard Phase IV 

Test bus operating on compressed hydrogen using 200 kW 

PEM fuel cell stack from Ballard, which was tested at 

SunLine; the bus currently resides at SunLine 

2001 Development FTA/Georgetown 40-foot FCB operating on methanol using 100 kW PEM fuel 

cell stack from Ballard 

2002-2003 Complete ISE/UTC 

ThunderPower 

ThunderPower 30-foot FCB operating on compressed 

hydrogen using 60 kW PEM fuel cell stack from UTC Fuel 

Cells at SunLine and AC Transit 

2003-2005 Complete CUTE, ECTOS, 

STEP 

Demonstration project in Europe, Iceland, and Australia 

including 33 FCBs using Ballard PEM fuel cell stacks and 

compressed hydrogen in 40-foot buses 

2003-2006 In-service Hino/Toyota FCB - 

JHFC 

Demonstration project in Japan including eight hybrid FCBs 

with Toyota PEM fuel cell stacks 

2004-2006 In-service VTA 

Demonstration project in San Jose, California: three FCBs 

using Ballard fuel cell stacks and compressed hydrogen in 

40-foot buses 

2004-2006 In-service UNDP-GEF China 

Demonstration project in China: three FCBs using Ballard 

PEM fuel cell stacks and compressed hydrogen in 40-foot 

buses 

2004- In-service SunLine 

Demonstration project in Thousand Palms, California: one 

FCB using UTC fuel cell stack and compressed hydrogen in 

a 40-foot bus at SunLine Transit Agency 

2004- In-service Hickam AFB 

Demonstration project in Honolulu, Hawaii: one battery 

dominant, plug-in hybrid, FCB with Hydrogenics PEM fuel 

cell and Enova hybrid system 

2005-2007 In-service AC Transit 

Demonstration project in Oakland, California: three FCBs 

using UTC fuel cell stacks and compressed hydrogen in 40-

foot buses 

2006-2007 In-service HyFLEET CUTE 

One-year extension of the demonstration of the 

Citaro/Ballard FCBs in Europe, Iceland, China, and Australia 

and new demonstration of 14 hydrogen fueled internal 

combustion engine buses (MAN) in Berlin, Germany 

2006- In-service NRCan/Hydrogenics Demonstration of one hybrid FCB using Hydrogenics PEM 

fuel cells (Canada) 

2007-2010 Planning FTA NFCBP 

Demonstration of FCBs in the US to advance the 

commercialization of the technology. Competitive 

solicitation to award $49M over four years to a selection of 

projects. 

2007- Planning UNDP-GEF Brazil Demonstration of five hybrid FCBs in Sao Paolo, Brazil 

2008- Planning BC Transit Operation of 20 hybrid FCBs in British Columbia, Canada for 

the 2010 Olympics 

Fleets choosing the diesel path were required to reduce the fleet average emissions through 

methods such as purchasing the cleanest diesel engines and retrofitting existing diesel engines 

with emissions control devices (i.e., diesel particulate filters). All transit agencies with 200 or 

more buses were subject to demonstrate and eventually procure ZEBs as 15% of all new bus 

 11
purchases. Fleets choosing the diesel path were scheduled to meet these requirements on a more 

accelerated timeline than fleets on the alternative fuel path. From model year 2008 through 

2015, 15% of new bus purchases by diesel-path transit agencies (with fleets larger than 200 

buses) must be ZEBs. The transit agencies that chose the alternative-fuel path are not required to 

purchase ZEBs at the 15% rate until 2010 (through 2015). 

Transit bus fleets on the diesel path with more than 200 buses were required to demonstrate the 

use of zero emission bus (ZEB) technology in revenue service starting in July 2003. ZEB 

technology includes electric propulsion (battery or trolley buses) or fuel cell propulsion. 

In June 2004, the regulations for the ZEB demonstration were modified, adjusting the required 

dates for the demonstration sites and clarifying how multiple transit agencies could execute the 

demonstrations in joint transit agency projects (as long as the joint partners are within the same 

air basin). The legislation required demonstrations to commence by February 28, 2006, and 

demonstration partners to submit demonstration result reports by July 31, 2007. 

VTA and SamTrans represent one of these joint transit agency partnerships to demonstrate fuel 

cell buses. This demonstration started revenue service on February 28, 2005—one year ahead of 

the required date in the legislation. 

Since the FCB demonstrations began, CARB has gathered data and experiences from California 

fleets (including VTA) demonstrating FCBs. Based on the early results, the board is considering 

further modification of the rules concerning ZEBs3. Although progress has been made in 

developing and demonstrating ZEBs, this progress has not been as rapid as initially projected. 

For example, the current purchase price of fuel cell buses is more than five times that of diesel 

buses. Purchasing 15% ZEBs under the current requirements would severely impact transit 

agency operations and the ability to provide public transportation. 

CARB is proposing modifications to the rule including an advanced demonstration program for 

ZEBs and a delay of the 15% purchase requirement. The advanced demonstration would be 

required by fleets on the diesel path beginning in 2009. Fleets could use FCBs from the current 

demonstration programs to meet the requirements of this advanced demonstration, but only if 

they are upgraded with advanced fuel cell systems representing the latest state of the art. The 

requirement for purchasing ZEBs would begin in January 2011 for diesel path fleets and January 

2012 for alternative fuel path fleets. For more information on the ruling, go to 

www.arb.ca.gov/msprog/bus/zeb/zeb.htm. 

Host Site Profile 

VTA (www.vta.org) was created in 1972 to oversee the region’s transportation system with the 

primary responsibility of operating and maintaining Santa Clara County’s bus and light rail 

system. In 1995, VTA was also charged with managing the county program to reduce 

congestion and improve air quality. VTA’s annual budget exceeded $295 million in fiscal year 

2005. It is directed by a 12-member board of directors. VTA operates 427 buses (345 buses in 

peak demand) and 100 light rail vehicles. In fiscal year 2005, annual ridership exceeded 37 

 

3

 California Environmental Protection Agency Air Resources Board, Staff Report: Initial Statement of Reasons, 

Proposed Amendments to the Zero Emission Bus Regulations, September 1, 2006. 

 12
million in a service area covering approximately 326 square miles (see Figure 2). In December 

2000, the organization adopted a Clean Fuels Strategy that included a zero emission bus 

program. In 2002, VTA entered into a contract with Gillig Corporation and Ballard Power 

Systems to procure three low-floor zero-emission fuel cell buses. 

SamTrans (www.samtrans.com) provides transportation services to San Mateo County, which is 

directly south of San Francisco. Fixed-route service at SamTrans started in 1976, and the district 

provides daily paratransit service. SamTrans’ fleet of 321 buses, vans, and sedans covers 

approximately 446 square miles and serves a population of more than 707,000 (Figure 2). 

Annual ridership was nearly 17 million in fiscal year 2002. SamTrans also manages Caltrain 

operations (76 trains each weekday) for a three-county joint powers authority including San 

Francisco, San Mateo, and Santa Clara counties. 

Figure 2. VTA and SamTrans operating area in California 

VTA/SamTrans ZEB Program 

VTA and SamTrans started planning their zero-emission bus demonstration in 2000 after each 

agency chose to embark on the CARB diesel path. VTA is the lead agency in the operation of 

these buses, and SamTrans shared in the demonstration planning and operation as well as the 

 13
capital and operating costs. Table 3 provides descriptions of the equipment and facilities 

involved in this demonstration. The goals of this demonstration program are to: 

• Determine the status of fuel cell technology in transit applications 

• Identify issues and challenges to overcome 

• Provide community outreach and educate the public on fuel cell and hydrogen 

technologies. 

Table 3. General Equipment for the Fuel Cell Bus Demonstration 

General Equipment Description Project Partner 

Bus manufacturer Gillig Corporation 

Buses Fuel cell manufacturer Ballard Power Systems 

System integrator Ballard in conjunction with Gillig 

Fueling Facility Compressed hydrogen station and liquid 

fuel delivery Air Products and Chemicals, Inc. 

Maintenance Facility 

Two maintenance bays have been built 

to properly maintain the buses; they 

include hydrogen detection and other 

safety systems 

VTA 

The budget for this demonstration was $18.5 million for a two-year demonstration project and 

includes: 

• Buses and operations: $14.1 million includes bus purchase (warranty, parts, training, and 

support), maintenance time, and marketing. 

• Facilities: $4.4 million includes fueling, maintenance, and bus wash facilities; fuel and 

other miscellaneous facilities-related expenses. 

This ZEB program is supported by a variety of government and industry partners. The partners 

and their respective roles are described below. 

• VTA leads the ZEB program, providing funding and the demonstration site. VTA used 

$6 million from a 2000 Measure A Local Sales Tax funding for this project. 

• SamTrans is working in partnership with VTA to demonstrate fuel cell buses, providing 

funding and demonstration support. SamTrans provided $6 million in funding for this 

demonstration project. 

• FTA leads the development of fuel-efficient mass transportation systems across the 

United States through financial, technical, and planning assistance. In addition to 

providing funding ($5.1 million) for the purchase of the buses used in the demonstration, 

FTA provided guidance in the evaluation strategy. 

• DOE provided funding directly to VTA for this project and to NREL for data collection, 

analysis, and reporting. 

• California Energy Commission (CEC) is the primary energy policy and planning 

agency for California. One CEC role is to help advance energy-related science and 

technology through research, development, and demonstration. The CEC’s 

Transportation Technology Office is involved with assessing the market potential of new 

transportation technologies, including fuel cell transit buses. CEC provides funding for 

the development and demonstration of these buses, as well as leadership for the bus team 

 14
of the California Fuel Cell Partnership (CaFCP). CEC provided $300,000 for this 

demonstration project. 

• Bay Area Air Quality Management District (BAAQMD) is one of California’s 

regional agencies dealing with air quality in the state. The district’s jurisdiction includes 

all or a portion of nine counties around the San Francisco Bay. BAAQMD supports the 

demonstration of clean propulsion technologies by providing funding, specifically $1 

million for this project. 

• Ballard Power Systems designs, develops, and manufactures PEM fuel cells for 

transportation and stationary applications. Ballard designed and integrated the fuel cell 

system for this demonstration and provides technical support for maintaining the buses. 

• Gillig Corporation produces heavy-duty buses. The company built the chassis for the 

buses in this demonstration and worked closely with Ballard on the integration of the fuel 

cell systems. Gillig also provides technical support for these buses. 

• Air Products supports a variety of customers by providing a wide range of products, 

including atmospheric gases, specialty gases, and chemicals. Air Products designed and 

constructed the fueling infrastructure at VTA and supplies the liquid hydrogen fuel used 

in this project. Air Products also owns the VTA station and is responsible for its 

maintenance. 

• CaFCP is a collaborative effort between auto manufacturers, energy companies, fuel cell 

technology manufacturers, and government agencies. The partnership brings together a 

diverse group of interested parties to accomplish common goals that include 

demonstrating fuel cell vehicles and supporting fueling infrastructure in real-world 

service. VTA is an associate member of CaFCP. 

• CARB has a mission to “promote and protect public health, welfare, and ecological 

resources through the effective and efficient reduction of air pollutants, while recognizing 

and considering the effects on the economy of the state.” CARB established its 

commitment to fuel cell transportation technology by passing several rulings, including 

the Public Transit Fleet Rule for California fleets. 

The VTA/SamTrans ZEB program was originally planned to include six or seven fuel cell buses 

at approximately $1.5 million each. However, the higher actual price of the fuel cell buses 

limited the demonstration to three vehicles. The first bus chassis was constructed by Gillig in 

April 2003 and shipped to Ballard for the installation of the fuel cell systems. This bus was run 

through a variety of tests prior to delivery to VTA in May 2004. The remaining two buses were 

entirely constructed at the Gillig facility in Hayward, California, and delivered to VTA in August 

2004. 

In September 2002, VTA awarded a lease contract to Air Products to install and maintain a 

hydrogen fueling facility at VTA’s Cerone Operations Division. Construction began in 

September 2003, and the station was completed by May 2004. VTA constructed a pad with the 

appropriate utilities including power and communication. Other demonstration-related 

construction projects included a new bus wash facility to accommodate the hydrogen fuel cell 

buses, which are 24 inches taller than the diesel buses, and a special two-bay maintenance 

facility that could accommodate hydrogen use inside the building. 

 15
The revenue service kick-off event for the VTA/SamTrans fuel cell bus demonstration was held 

at VTA’s Great Mall/Main Transit Center in Milpitas, California, on February 24, 2005—a few 

days prior to beginning revenue service on February 28, 2005. 

 16
Ballard Fuel Cell Development and Testing 

Ballard Power Systems, Inc. (www.ballard.com) is headquartered in Burnaby (near Vancouver), 

British Columbia, Canada, and was founded in 1979 as a research company investigating highenergy lithium batteries. Ballard started work on PEM fuel cells in 1983 and began 

demonstration of this fuel cell technology in transit buses in 1991 (Table 4). Ballard has been 

working to commercialize fuel cells for transportation applications as well as electrical 

equipment and portable power. Ballard reports that these fuel cell systems have evolved into 

pre-commercial prototypes and initial commercial products. Current work on fuel cells at 

Ballard focuses on reducing cost, increasing durability, improving freeze start, and increasing 

power density. 

Table 4. Ballard Fuel Cell Development Phases 

Phase Timeframe Bus/Fuel Cell 

Module No. of Buses 

Phase 1: Proof of Concept 1991-1992 Small bus/MK500, 

100kW One 

Phase 2: Commercial Prototype 1993-1995 Bus/MK513, 

200 kW One 

Phase 3: Fleet Demonstration –

Alpha Sites 1996-1999 Bus/MK513, 

200 kW 

Three in Chicago and 

three in Vancouver 

Phase 4: Fuel Cell Engines 1999-2002 Bus/MK705, 

200 kW One 

Phase 5: Serial Production 2002-2006 Bus/P5-2, 

300 kW 39 around the world 

 Source: Ballard presentation in Vancouver, 2005 

Phase 1: Proof of Concept—Ballard developed a proof-ofconcept bus with a working PEM fuel cell propulsion system 

using compressed hydrogen in the 1991-1992 timeframe. The 

vehicle was a small 20-passenger shuttle bus with a 100 kW fuel 

cell system. Range of the vehicle was reported as approximately 100 miles. 

Phase 2: Commercial Prototype—The next fuel cell bus from 

Ballard was a 40-foot New Flyer low-floor bus in the 1993-1995 

timeframe. This 60-passenger bus used 20 fuel cell stacks and 

had a range of 250 miles on compressed hydrogen and a power 

plant rated at 200 kW. The challenges for this bus were weight, fuel economy, and 

maintainability. Successes from this demonstration were reported to be significant work in 

systems integration and improved component selection for the fuel cell propulsion systems. 

Phase 3: Fleet Demonstration-Alpha Sites—Phase 3 was a much 

more ambitious demonstration: six fuel cell buses split between two 

transit agencies, Chicago Transit Authority and Coast Mountain Bus 

in Vancouver. These buses were essentially the same as the New 

Flyer bus in Phase 2 with some advances based on lessons learned in 

Phase 2. This development and demonstration effort spanned 1996-

1999. Phase 3 was a full-scale demonstration that included facility adaptation to the use of 

 17
hydrogen and the inclusion of transit agency personnel in operations and maintenance for the 

fuel cell buses. The following objectives for this phase were reported by Ballard: 

• Learn about fuel cell technology in real, everyday operation and transfer that knowledge 

to subsequent engine and component development phases 

• Gain an understanding of vehicle performance, failures, and operating costs 

• Better understand the infrastructure required for the operation of this technology 

• Prepare the market for the entrance of fuel cell vehicles 

• Educate the public on the safety and reliability of fuel cell vehicles 

• Prepare and train potential transit customers to work with fuel cell vehicles. 

Lessons learned in this phase included the need for additional work in durability of the 

propulsion systems and experience working within the two colder climate areas. Successes 

included learning about meeting the needs of working in two locations and creating training 

programs for transit personnel. Some revenue service was completed with these buses. A highlevel summary report for this demonstration can be found at 

www.cleanairnet.org/infopool/1411/articles-35634_cleaning_up.pdf. 

Phase 4: Fuel Cell Engines—Ballard focused on vehicle performance 

in Phase 4 with one New Flyer low-floor bus, called the zero emission 

bus (ZEbus). The fuel cell propulsion system was made smaller 

(higher power density) with eight fuel cell stacks instead of the 20 in 

the previous two phases. This 60-passenger bus had a range of 250 

miles on 48 kg of compressed hydrogen, and the power plant was rated at 200 kW. This bus was 

tested as a demonstration at SunLine Transit Agency in the 1999-2002 timeframe. SunLine 

operates in the desert in the Coachella Valley, near Palm Springs, California. This 

demonstration was an opportunity to test the fuel cell propulsion systems in high-temperature 

and low-humidity operations. 

Challenges in this phase were reported as temperature, weight, and cooling; successes were 

meeting the challenges and training collaboration with the Coachella Valley’s College of the 

Desert. These training materials are available at 

www.eere.energy.gov/hydrogenandfuelcells/tech_validation/h2_manual.html. Lessons learned 

from this phase were the need for cooling system improvement and fuel cell propulsion 

component improvements for inverter cooling and traction drive. A final summary report for 

this demonstration can be found at 

www.eere.energy.gov/hydrogenandfuelcells/tech_validation/pdfs/sunline_final_report1.pdf. 

Phase 5: Serial Production—Phase 5 has been the most ambitious 

demonstration to date. Under funding from the European Union (EU), 

DaimlerChrysler and Ballard embarked on an 11-city fuel cell bus 

implementation and demonstration program, which included 33 

Mercedes-Benz Citaro buses. The goals of the project included: 

• Demonstrate fuel cell buses and hydrogen infrastructure in parallel to provide regular 

transit service 

 18
• Investigate the potential of providing hydrogen mainly using renewable resources 

• Determine if the buses and infrastructure could meet availability rates of conventional 

technologies 

• Assess the level of acceptance of the technology in the general public and transit staff 

• Demonstrate the safe use of hydrogen fuel. 

 

The timeframe for this phase was 2002 through 2006. Each of the following 11 cities was part of 

the demonstration, operating three buses per site: 

• Clean Urban Transport for Europe (CUTE) 

o Amsterdam, Netherlands 

o Barcelona, Spain 

o Hamburg, Germany 

o London, England 

o Luxembourg, Luxembourg 

o Madrid, Spain 

o Porto, Portugal 

o Stockholm, Sweden 

o Stuttgart, Germany 

• Ecological City Transport System (ECTOS) 

o Reykjavik, Iceland 

• Sustainable Transport Energy for Perth (STEP) 

o Perth, Australia. 

The first of these FCBs was placed in service for the ECTOS project in Reykjavik, Iceland. The 

project partners presented the results of the two-year demonstration in April of 2005. (Project 

reports are posted online at http://newenergy.is/en/projects/finished_projects/ectos.) The results 

from the two-year CUTE demonstration were presented at a conference in Hamburg, Germany 

on May 10–11, 2006. The presentations from the conference are available online at www.cutehamburg.de/. A report detailing the achievements of the nine fleets in the CUTE project was 

published in late summer 2006. This report is located in the publications section of the CUTE 

Web site at www.fuel-cell-bus-club.com. During the CUTE project, the buses operated for over 

850,000 kilometers (over 526,000 miles) and 62,000 fuel cell system hours. The project partners 

learned many valuable lessons, which are outlined in the reports. 

An additional three Citaro fuel cell buses with the Ballard fuel cell system were 

placed into service in Beijing, China in June 2006. This project was co-funded 

by the United Nations Development Program/Global Environment Facility 

(UNDP-GEF). The buses in service are identical to the buses used for the 

CUTE project. The demonstration in China involves two cities, Beijing and 

Shanghai. The Beijing demonstration is Phase 1 of the project. The goals are t

accelerate the commercial application of FCBs in China and to promote a “Green 

Game” in Beijing in 2008. For Phase 2, a next generation FCB will be procured to opera

Shanghai. 

o 

Olympic 

te in 

 19
HyFLEET:CUTE—After the original two-year CUTE project, an extension of one year of 

operation was approved with continued funding from the EU. Ten cities on three continents are 

participating in this project to demonstrate hydrogen fueled buses. The demonstration includes 

hydrogen fueled internal combustion engine (ICE) buses as well as the FCBs introduced in the 

previous CUTE project. The additional year of operation for the existing FCBs has the general 

objectives of getting more operating experience and possibly taking the fuel cell propulsion 

system to failure. The fuel cell buses from two cities not participating in the additional operation 

were transferred to Hamburg, giving the fleet a total of nine buses. Participating cities include: 

• Fuel Cell Bus 

o Amsterdam, Netherlands 

o Barcelona, Spain 

o Beijing, China 

o Hamburg, Germany 

o London, England 

o Luxembourg, Luxembourg 

o Madrid, Spain 

o Perth, Australia 

o Reykjavik, Iceland 

• Hydrogen ICEs (manufactured by MAN) 

o Berlin, Germany. 

VTA Fuel Cell Bus Demonstration—The VTA fuel cell buses also have a fuel cell propulsion 

system that is essentially the same as the other buses in the Phase 5 programs. However, the 

VTA buses use the Gillig low-floor bus model. The packaging and integration for VTA’s three 

fuel cell buses are significantly different than the Mercedes-Benz Citaro buses used for the other 

Phase 5 sites. 

 20
Infrastructure and Facilities 

VTA has three depots for bus operations—Cerone, Chaboya, and North. The Cerone operating 

division was selected as the home of the fuel cell bus program primarily because of space 

availability. The Cerone operations 

include 137 buses operating seven days a

week plus the three ZEBs. The 

infrastructure and facilities added at 

Cerone for fuel cell bus operations 

included a compressed hydrogen fueling 

station, a stand-alone two-bay 

maintenance facility, and an upgraded 

bus wash to accommodate the taller 

hydrogen fueled buses. 

Compressed Hydrogen Dispensing Station 

VTA issued a request for proposal for the hydrogen dispensing station in January 2002 and 

awarded a contract to Air Products in September 2002 for the installation and lease of the fueling 

facility. Under the capital lease agreement for the facility (Figure 3), Air Products retains 

ownership of the equipment at the facility and is required to maintain the facility. VTA 

constructed the concrete pad with all the necessary utilities, including power, grounding, 

communications etc., in accordance with Air Products requirements. 

Figure 3. Compressed hydrogen dispensing station 

at VTA's Cerone Operations Division 

Construction of the station began in September 2003, and the station was completed in May 

2004; however, actual hydrogen dispensing at the station did not start until November 2004. For 

the installation and lease of the fueling station as well as applicable training, VTA paid Air 

Products approximately $480,000 up front and has monthly payments for three years (about 

$4,400 per month). This amounts to a grand total of approximately $640,000 for the station. 

 21
This does not include the cost of the hydrogen fuel delivered. The fueling facility was designed 

to operate six hydrogen fuel cell buses. Cost factors reduced the number of buses to three. 

The station features a 9,000 gallon cryogenic tank that stores liquid hydrogen. Prior to use, the 

liquid hydrogen is compressed to 6,000 psi and vaporized for secondary storage in a pressurized 

six-tank cascade. Air Products’ liquid compression system enables fast filling of the buses. The 

fueling island dispenses pressurized gaseous hydrogen into the fuel cell buses from the cascade, 

which acts as a buffer. The cascade holds enough hydrogen to begin the fueling process. When 

the hydrogen in the cascade tanks drops below a preset pressure, the compressor is activated and 

continues fueling the buses to the maximum fill level. The cascade tanks are also refilled during 

this process. 

The hydrogen dispenser (Figure 4) is equipped for a communications fill. The communications 

allow for monitoring tank pressure and temperature, and the cable also provides a connection to 

electrical ground. When using the communications cable, a full hydrogen bus fill can be 

performed in approximately 10 minutes. A non-communication fill can take upwards of 20 

minutes. Figure 5 shows the fueling hose and the communications connections on the bus during 

a fill. 

Figure 4. Hydrogen dispenser 

 22
Figure 5. Hydrogen fueling connection (left) and communications connection (right) on the FCB 

The station design includes two compressors to avoid downtime for the fleet. This allows the 

station to continue operation when one of the compressors undergoes scheduled maintenance or 

experiences a failure. As a newer and experimental Air Products design, one of the compressors 

can provide a fast fill in about eight minutes (designated as prototype compressor in the 

following discussion). The other compressor is a reliable, proven design that provides a full bus 

fill in less than 20 minutes (designated as the primary compressor). 

To ensure high reliability and safety, the station includes numerous devices to alert VTA and Air 

Products of potential problems. These devices include flame, earthquake, pressure, and 

temperature sensors; alarms; and emergency stop (E-stop) buttons (Figure 6) that are monitored 

on site by VTA and remotely by Air Products. When activated, these devices will shut down the 

system and close the liquid tank valves. 

 

Figure 6. Flame sensors (left and top) and emergency shut-off (right) 

at the hydrogen dispensing facility 

 23
VTA uses its two assigned fuel cell bus mechanics to dispense hydrogen into the buses. To 

ensure safety, only trained personnel are authorized to dispense hydrogen from the station. The 

Ballard assigned mechanic and Air Products staff can also work with the hydrogen dispensing 

equipment. VTA's facility maintenance staff is also familiar with the facility and can respond to 

trouble notification, as required. 

Early Experience with Hydrogen Dispensing—Operating and maintaining the requisite 

hydrogen fueling infrastructure for the fuel cell bus demonstration was an early challenge. VTA 

experienced several problems and delays in the process of building and commissioning the 

fueling station. Because hydrogen infrastructure is in the early stage of development, precedent 

for building stations has not yet been set—except in a few locations. Each station installation is 

unique, with various approaches to producing and dispensing hydrogen. When planning its 

station, VTA staff cited the need for a uniform approach to codes and standards as well as 

standardized interfaces and fueling connectors. Some of the early issues encountered by VTA 

are summarized below. 

During the commissioning of the station in May 2004, the discharge thermocouple on the 

primary compressor failed, causing a liquid hydrogen leak that subsequently ignited. This 

thermocouple monitors the discharge temperature and controls the compressor. The system was 

going through checkout and commissioning at the time of the leak, and the E-stop was activated 

within seconds. In addition, system safety controls automatically activated the liquid tank’s 

emergency shutoff valves. Damage was minimal and limited to the immediate area where the 

leak and fire occurred. There were no injuries. Air Products determined that the failure was the 

result of a design defect in the thermocouple. All thermocouples of that type and manufacturing 

batch were replaced, including units installed at two other facilities. Although no major damage 

resulted from the fire, the station was shut down for investigation, repair, and inspections by 

local fire officials. This ultimately delayed the start of full operation of the dispensing station 

until November 2004. 

Multiple false alarms, which triggered calls to the local fire department, also caused delays to 

VTA’s station operation. Procedures in place required the fire department to be directly 

contacted in the case of a fire alarm without independent alarm verification by personnel. This 

revealed issues that could be avoided at future stations by modifying the standard procedure. 

The majority of the alarms were traced to one of the following causes: 

• Power Loss: In the case of a power loss, safety systems at the VTA facilities are placed 

on a back up power supply. Originally, when power was restored, the system would 

remain on the back up power supply, including the safety systems, until they were 

manually reset to the standard grid power supply. As this was unknown by VTA and Air 

Products personnel on site, a temporary power loss occurred, but the system wasn’t 

manually reset. This condition caused the back up power supply to be drained and the 

fail-safe safety system to alarm. On two occasions, false alarms were determined to be 

caused by temporary power losses at the fueling station. This has been changed so that 

when power is restored, the safety system is automatically returned to grid power and the 

back up power supply is recharged. 

 24
• Detector Sensitivity: Safety systems are in place to detect conditions that may pose a 

danger or signal an incident. Sensors and detectors are extremely sensitive and were 

triggered by events such as maintenance work in the area. Investigation of events at VTA 

showed that maintenance work, including grinding or welding as far as 400 feet away, 

most likely caused the false alarms. This experience resulted in the development and 

installation of improved flame detectors as well as the implementation of new 

procedures. 

• Detector Failure: The detectors were replaced due to a manufacturing defect. 

Because most of the false alarms occurred during or shortly after maintenance work was 

performed, VTA now requires advanced notification of work on or near the hydrogen facilities. 

During this time, the systems are placed in test mode. Valuable experience was gained on the 

flame detectors during the initial operation of the station. As a result of the numerous problems 

experienced with the ultra-violet flame detector, a new and improved infra-red flame detector 

was installed. This new detector greatly improved reliability and reduced the number of false 

alarms.

Several incidents occurred at the VTA station that resulted in excessive venting or hydrogen 

leaks. On at least three separate occasions, vapor clouds were detected by VTA personnel at the 

hydrogen fueling facility. 

The first incident occurred in October 2004. It involved a small leak and vapor cloud at the front 

of the liquid hydrogen storage tank. The leak occurred at the stem packing of a cryogenic valve. 

VTA personnel signaled for an evacuation and pulled the fire alarm to notify the fire department. 

An Air Products technician diagnosed the problem and stopped the leak by tightening the 

packing vent valve. Although the repair was simple and quick, the incident involved the San 

Jose fire and police departments and resulted in a temporary evacuation of the facility. Several 

training issues were discovered during the incident. The local E-stop, or remote shut down 

using the electrical breaker, was not activated by personnel on site; however, this would not have 

stopped the leak. Additionally, a faulty fire alarm pull box did not signal the fire department. 

The second incident, which occurred in February 2005, involved a small leak and vapor cloud at 

the fueling facility. The leak occurred at the prototype cryogenic compressor. VTA personnel 

activated the E-stop at the dispenser to shut down the system and notified Air Products. The leak 

was isolated and the system was placed back into service with the primary cryogenic 

compressor. Repairs were made to fix the leak and the prototype cryogenic compressor was 

returned to service. 

The third incident occurred during a bus fueling at the station in May 2005. The prototype 

cryogenic compressor continued to operate, but was not providing any hydrogen flow into the 

system or the fuel cell bus. The system was venting excessively and continuously. The bus 

fueling was stopped and VTA staff notified Air Products. The prototype compressor kept 

running even though the cascade tanks were not filling and venting continued. When the 

prototype compressor shut down, the primary system came online as back up. VTA personnel 

then noticed a leak and vapor cloud at the primary compressor. VTA personnel shut down the 

entire system using the E-stop button. An Air Products technician corrected the primary 

 25
compressor leak to get the system back online. The prototype compressor needed more 

extensive repairs, necessitating the continued use of the primary compressor. 

Although these issues were addressed and resolved, use and operation of the hydrogen station 

caused challenges for the fleet. Multiple problems with the various systems at the station caused 

delays that directly affected VTA’s ability to provide service to its customers. Many of the 

alarms resulted in calls to the San Jose fire department, which dispatched fire trucks that were 

not technically needed. VTA staff members cited concerns that repeated false alarms could 

erode the company’s relationship with the local fire department. VTA continues to work with 

project partners to prevent future problems from occurring and to fully train onsite personnel, 

fire officials, and emergency responders to handle hydrogen-related incidents. 

By the time the buses were placed in service, many of the early issues and problems had been 

resolved. Hardware modifications, software updates, and changes to procedures for operating 

and maintaining the station helped resolve many of the issues. Since February 2005, there have 

been several other minor incidents involving leaks or excessive venting; however, many of those 

incidents were isolated to the newer design (prototype) compressor. Because the primary 

compressor was not affected, the fueling station was still operational. In all, there were seven 

events classified as leaks in the system from station commissioning through July 2006. Only 

four of these incidents occurred after the buses went into service. The system experienced only 

four shutdowns during this time, resulting in a combined total of four days when the station was 

not available for fueling the three fuel cell buses. Of the total 11 false alarms at the station, only 

five occurred after the buses went into service. 

It is important to recognize that this is a demonstration project and that some of the technology 

used in the hydrogen dispensing station is in early deployment and use. As with any 

demonstration project, problems should be expected, especially during the first months of 

operation. While the prototype compressor has had multiple issues resulting in failures and 

major downtime, the primary compressor has proven to be extremely reliable. The prototype 

(newer design) compressor is in testing by Air Products. The early experience with this 

prototype compressor has provided them with valuable data to enable further optimization and 

design modifications. 

Hydrogen Fuel Dispensing Analysis—The first liquid hydrogen fuel shipment occurred in May 

2004. This fuel was used to test the fuel station systems. Actual bus fueling did not start until 

November 2004. Through July 2006, the fueling station had 31,836 kg of hydrogen delivered; 

14,024 kg of hydrogen were dispensed into buses. Originally designed for the operation of six 

fuel cell buses, with only 3 buses, station use has been less than anticipated with the original 

design. This has potentially affected hydrogen loss due to boil-off. With the buses operating 

since late February 2005, vent and boil-off losses have been at 50%. Air Products reports that if 

the station throughput had been greater, the hydrogen losses would have been significantly 

reduced. 

Figure 7 shows average hydrogen dispensing amounts and times per fueling. As mentioned 

earlier, fuelings at the beginning of the station operation took an average of about 20 minutes. 

Since April 2005, the fueling times improved considerably, with fill times averaging between 12 

 26
and 18 minutes. During the 17-month evaluation period, the hydrogen dispensing station 

provided 460 fuelings with an overall average fill at 16 minutes, 30.9 kg/fill, and 1.93 kg/min. 

According to Air Products, further optimization of the station could result in reductions in 

fueling time. Figure 8 shows a histogram of fueling rates for the buses since the station began 

operation in November 2004. 

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

45.0

Nov-04

Dec-04

Jan-05

Feb-05

Mar-05

Apr-05

May-05

Jun-05

Jul-05

Aug-05

Sep-05

Oct-05

Nov-05

Dec-05

Jan-06

Feb-06

Mar-06

Apr-06

May-06

Jun-06

Jul-06

Average kg per Fueling Average Fueling Time (min)

Figure 7. Average hydrogen fueling amounts and average fueling time 

Figure 9 shows average hydrogen fuel cost over time. For most of the period shown, the 

hydrogen cost was between $8 and $9 per kg of hydrogen. The price increased considerably in 

October 2005 and November 2005 to $10.39 per kg of hydrogen, but came back down again in 

March 2006. The average hydrogen cost delivered to the station during the evaluation period 

was $9.06 per kg. This equates to an approximate cost of $10.24 per diesel equivalent gallon. 

Based on the loss of hydrogen due to venting and boil-off, the cost of hydrogen fuel might be 

considered to be double ($18.19 per kg). 

 27
Figure 8. Fueling rate histogram for VTA hydrogen station 

Diesel Fuel Cost—During the evaluation period, the diesel fuel cost at VTA was tracked as a 

monthly average cost per gallon, as shown in Figure 10. The diesel fuel at VTA is ultra low 

sulfur diesel with a sulfur content of less than 15 parts per million (ppm). The diesel fuel cost 

started out well below $2 per gallon and increased in August 2005 (as it did in the rest of the 

country). The average diesel fuel cost per gallon for the evaluation period was $2.07. 

 28
0.00

2.00

4.00

6.00

8.00

10.00

12.00

Nov-04

Dec-04

Jan-05

Feb-05

Mar-05

Apr-05

May-05

Jun-05

Jul-05

Aug-05

Sep-05

Oct-05

Nov-05

Dec-05

Jan-06

Feb-06

Mar-06

Apr-06

May-06

Jun-06

Jul-06

Hydrogen Cost ($) per kg

Figure 9. Average fuel cost ($/kg) for liquid hydrogen delivered to VTA station 

0.00

0.50

1.00

1.50

2.00

2.50

3.00

Mar-05

Apr-05

May-05

Jun-05

Jul-05

Aug-05

Sep-05

Oct-05

Nov-05

Dec-05

Jan-06

Feb-06

Mar-06

Apr-06

May-06

Jun-06

Jul-06

Diesel Fuel Cost ($) per Gallon

Overall Diesel Fuel Cost

Figure 10. Average diesel fuel cost ($/gallon) at VTA (March 2005 through July 2006) 

 29
Hydrogen Bus Maintenance Facility 

A separate maintenance facility was designed and built for the ZEB demonstration. The new 

facility was required in order to accommodate the hydrogen rating for the maintenance of the 

hydrogen fuel cell buses, without the requirement for de-fueling or purging, in accordance with 

building codes and the fire marshal’s requirements. This two-bay facility, shown in Figure 11, 

houses the equipment and spare parts needed to maintain and repair hydrogen fuel cell buses. 

Like the fueling station, the maintenance building is equipped with the necessary devices to 

enable safe operation and maintenance of hydrogen vehicles. The building is equipped with 

Class I Div. II electrical fixtures, a hot water heating system, hydrogen and flame sensors, and an 

anti-static coating on the doors. When sensors detect significant amounts of hydrogen, alarms 

are triggered. At a lower flammability limit (LFL) of 15% (0.6% hydrogen in air), the doors 

open and fans are automatically activated to clear the air in the building. At 50% LFL (2% 

hydrogen in air), electrical systems (except safety systems) are shut down and evacuation is 

required. It should be noted that the only source of hydrogen in this facility is the fuel cell bus. 

Therefore, if no bus is in the building, an activation of a hydrogen alarm would be a false alarm. 

The new bus wash (Figure 12), planned as part of the Cerone improvement program, was also 

designed and constructed to allow for the added height of the fuel cell buses due to the hydrogen 

fuel storage tanks on the roof. This included higher brushes and rinse arches as well as a fire 

sprinkler system. The roof design also allows for proper ventilation and any hydrogen release to 

escape safely. 

Figure 11. Maintenance facility used for the fuel cell buses at VTA 

Control panels for the wash operation within the bus wash facility were required to have an 

active nitrogen purge within the panel to keep any hydrogen away from the electronics within the 

sealed control panel. One of the control panels was moved outside of the bus wash facility to 

remove the need for the nitrogen purge. The total cost for adding these three facilities to meet 

the requirements of operating the hydrogen fuel cell buses was $4.4 million. 

 30
Figure 12. Bus wash 

Experience with Maintenance and Bus Wash Facilities – VTA encountered several challenges 

in adding these new buildings to the site. The maintenance building was one year behind 

schedule and it took much longer to get the building approved for use by safety officials. The 

majority of the building construction was completed in June 2005; however, the fleet did not get 

approval for use until November of that year. Early issues with the fueling station caused 

officials to be extra cautious regarding safety in the maintenance facility. VTA also had 

difficulties getting the required hydrogen sensors delivered and installed in the building. Once 

the system was installed, there were additional difficulties with communications between the 

sensors and control panel, causing further delays. 

There have been several incidents (through July 2006) in the maintenance facility since it was 

approved for use. In one incident, the 15% LFL alarm was triggered during a preventive 

maintenance (PM) inspection of a fuel cell bus. The 7,500 mile PM for the FCB requires a test 

of the purge system on each fuel cell. During the test, the bus is operated while the purge valve 

is open. To expedite the process, the maintenance staff purged both fuel cell stacks 

simultaneously. This continuous purging of both stacks proved to be in excess of what the 

hydrogen diffuser on the bus could handle, allowing the hydrogen level to rise above the 15% 

threshold for the sensors. (In this case, the bus was parked such that the diffuser was almost 

directly under a hydrogen sensor.) An alarm was activated, which triggered the doors to open 

and facility ventilation to increase. Maintenance staff turned the bus off and checked the 

monitors for hydrogen level, which dropped from 13% LFL to zero in seconds. The safety 

systems in the maintenance facility worked as designed. The staff alerted the authorities that no 

emergency response was necessary and continued the PM. For future tests of the purge system, 

each fuel cell was tested separately. There have been several other incidents where the 15% LFL 

alarm was triggered. It was found that these were false alarms and were caused by faulty 

sensors. The sensors have been replaced. 

 31
Fuel Cell and Diesel Bus Descriptions 

In June 2002, VTA awarded a contract to Gillig Corporation to build three buses featuring fuel 

cell propulsion systems by Ballard Power Systems. The first bus chassis was constructed by 

Gillig in April 2003 and shipped to Ballard’s Canadian headquarters in Burnaby (near 

Vancouver), British Columbia, for the installation of the fuel cell system. This bus was run 

through a variety of tests, and the integration was finalized prior to delivery to VTA in May 

2004. The remaining two buses were entirely constructed at the Gillig facility in Hayward, 

California, with Ballard staff support and delivered to the fleet in August 2004. The buses cost 

$10.6 million ($3.5 million each). This price includes system integration engineering, a two-year 

warranty, parts, training, and support from Gillig and Ballard. 

Table 5 shows a summary of vehicle system descriptions for the fuel cell and diesel baseline 

study groups of buses. Figure 13 shows both types of buses. Both bus groups are Gillig lowfloor buses; however, the fuel cell buses are slightly newer than the diesel buses. The fuel cell 

buses are 24 inches taller than the diesel buses, which caused some concerns at VTA about 

clearance. Issues such as low-hanging tree limbs were taken into account. Additionally, the fuel 

cell buses are 6,800 lb heavier than the diesel buses. This restricted the maximum number of 

passengers to include all seats and five standees in the fuel cell buses (compared to all seats and 

43 standees in diesel buses). Both groups of buses have a transit bus transmission with an 

integral retarder. Neither the diesel nor the fuel cell buses have hybridized systems, and 

therefore do not have regenerative braking or additional energy storage. Table 6 provides more 

information on the fuel cell propulsion system. 

Table 5. Fuel Cell and Diesel Bus System Descriptions 

Operation from Cerone Depot Vehicle System Fuel Cell Buses Diesel Buses 

Number of Buses 3 5 

Bus Manufacturer and Model Gillig low-floor Gillig low-floor 

Model Year 2004 2002 

Length/Width/Height 40 feet/102 in/144 in 40 feet/102 in/120 in 

GVWR/Curb Weight 40,600 lb/34,100 lb 39,600 lb/27,300 lb 

Wheelbase 284 in 284 in 

Passenger Capacity 37 seated or 

29 seated and two wheelchairs 

five standing 

38 seated or 

31 seated and two wheelchairs 

43 standing 

Engine Manufacturer and Model Two Ballard fuel cell modules P5-2 Cummins ISL (8.9 liter) 

 Rated Power 150 kW each (300 kW total) 280 bhp @ 2,200 rpm 

 Rated Torque 790 lb-ft @ 1,350 rpm (1250 Nm) 900 lb-ft @ 1,300 rpm 

Accessories Mechanical Mechanical 

Emissions Equipment None Diesel oxidation catalyst 

Transmission/Retarder ZF transmission/integrated retarder Voith transmission/integrated retarder

Fuel Capacity Approx. 55 kg hydrogen 

at 5,000 psi 

115 gallons 

Bus Purchase Cost $3.5 million (average) $316,000 

 32
Figure 13. Fuel cell bus (left) and diesel bus (right) 

Table 6. Additional Fuel Cell Propulsion System Descriptions 

Propulsion Systems Fuel Cell Buses 

Manufacturer/Integrator Gillig/Ballard 

Drive System Fuel cell power plant, inverter, one electric propulsion motor, six-speed transmission 

Propulsion Motor Reuland Electric, three-phase induction motor rated at 225 kW 

Energy Storage None (not hybrid) 

Fuel Storage Eleven, roof mounted, Dynetek Dynecell carbon fiber-wrapped tanks 

VTA conducted some performance testing of the fuel cell buses. Testing was completed on fuel 

cell bus 4002 in May 2005. The maximum speed was demonstrated as 70 mph. Fuel efficiency 

testing was completed on a test route to maximize operation near 55 mph. This testing included 

105 miles of operation and a fuel efficiency of 5.3 miles per kg of hydrogen, which indicated a 

maximum range of 275 miles. 

Acceleration testing (based on the APTA Standard Bus Procurement Guidelines requirement) 

was completed on all three fuel cell buses in March 2006. This testing was done at gross vehicle 

weight for the buses. Table 7 shows the expected times to reach 20, 30, and 40 mph along with 

the actual average times to reach those speeds. These average times for fuel cell bus acceleration 

were better than the requirement for all three speed milestones. 

Table 7. Fuel Cell Bus Acceleration Testing Results (March 2006)

Speed (mph) Target Time (sec) Tested Average Time (sec) 

20 11.0 9.1 

30 20.0 16.5 

40 31.0 28.0 

VTA Fuel Cell Bus Operation 

VTA has two mechanics assigned to the fuel cell bus project that were trained at Ballard to work 

on the fuel cell modules and propulsion system. Ballard also had a mechanic on site at VTA 

since the buses were delivered through the end of warranty support in July 2006. The VTA FCB 

mechanics maintain and support all aspects of the FCB operation including: 

• Vehicle, fuel cell module, and fuel system inspections 

• Hydrogen fueling 

• Bus cleaning 

• All vehicle maintenance (also supported by the Ballard technician) 

• Parts management 

• Coordination and troubleshooting with Ballard technical support (in Canada) 

• Coordinating with visitors and fire department personnel. 

 33
VTA’s procedure for operating the fuel cell buses includes a pre-trip inspection by a VTA FCB 

mechanic while the fuel cell systems are “warming up.” The fuel cell bus system enters a startup mode when the key is turned on. This initiates: 

• The electric motor going into idle mode 

• The air compressor starting airflow to the cathode side of the fuel cell 

• The hydrogen pressure regulator starting the hydrogen flow to the anode side of the fuel 

cell. 

The inverter is switched on when the power from the fuel cell reaches a minimum operating 

voltage for the motor and inverter. Once conditions are stabilized, the bus is ready to drive. The 

bus can be driven immediately; however, full power operation typically takes 15 to 20 minutes. 

During driving, the electricity from the fuel cell feeds the motor to provide traction for the bus 

and power for the auxiliaries (air compressor, air conditioning, alternator, etc.) and inverter. As 

the driver presses the accelerator pedal, air flow and hydrogen pressure are increased to provide 

the requested power. The system uses valves and regulators to strictly control the air and 

hydrogen flow. 

At the end of operation, the fuel cell propulsion system goes through a shut-down procedure, 

which is triggered by the driver (key-off) or safety system. The valves for each hydrogen fuel 

cylinder/tank are closed while any hydrogen remaining in the lines is evacuated through the 

purge diffuser. The traction motor stops turning and the electrical systems are disconnected. 

At the end of the work day for a FCB, the VTA FCB mechanics take the bus and fill it up with 

hydrogen at the dispensing station and then re-park the buses in their specified parking spots near 

the hydrogen maintenance facility (Figure 14). 

Figure 14. Fuel cell buses parked at the maintenance facility 

 34
Early Experience with VTA’s Fuel Cell Buses 

Because fuel cell bus technology is new to the transit industry and this fleet, VTA took a 

conservative approach to the demonstration. Once hydrogen fuel was available, the fleet 

operated the buses in test mode for several months (November 2004 through February 2005). 

This test mode operation was conducted to identify problems and allow drivers and maintenance 

staff to become familiar with the differences between the fuel cell and conventional buses. 

During this time, VTA made the fuel cell buses available for training VTA staff and conducting 

familiarization classes for local fire officials and first responders. After an official kick-off event 

in late February 2005, the buses began extra revenue service. 

VTA has experienced several issues and challenges demonstrating fuel cell buses. Some 

comments regarding early experience with the fuel cell buses are summarized below. 

 

• Sensor Defect: Due to a materials compatibility issue, a pressure-sensing device on the 

fuel cell system was determined to be faulty. At that time, VTA had received only one of 

the three buses. At the recommendation of the bus manufacturer, VTA did not operate 

the bus until the issue was resolved. The sensor manufacturer developed a new pressure 

sensor using materials appropriate for high-pressure hydrogen applications. The sensors 

were replaced on the first bus at VTA and installed on the remaining buses at the Gillig 

manufacturing facility prior to delivery. 

• Bus Height: The compressed hydrogen cylinders roof-mounted on the fuel cell buses add 

24 inches to the height of a standard bus. The added height meant the buses did not fit 

through VTA’s existing bus wash. A new bus wash was designed and constructed to 

allow for the washing of the hydrogen fuel cell buses. The added height also necessitated 

extra precautions when placing the buses on specific routes. The buses were designed 

with crash sensors on the roof that shut down the buses (and isolate the fuel tanks) if a 

collision occurs. VTA inspected routes for obstacles, such as low hanging tree branches, 

to avoid potential shut down of the bus while in service. 

• Bus Weight: Because fuel cell buses are heavier than typical 40-foot buses, the fleet has 

to limit the number of standing passengers to meet weight requirements. This could be 

an issue when operating on higher-use routes where standing passengers are common. 

• Range: The lower range of the buses also limited the routes and schedules that the buses 

could operate. The range of a standard diesel bus is approximately 400 miles in revenue 

service as compared to approximately 140 miles for the fuel cell buses. 

• Parts Availability: VTA’s contract for purchasing the buses includes a certain number 

and type of replacement parts for bus repair. Transit agencies typically stock a large 

selection of parts for each type of bus they operate. This enables quick repairs of most 

failures and reduces downtime. While standard bus parts are readily available from 

Gillig, parts for the advanced fuel cell propulsion system were not always easy to obtain. 

Waiting for these replacement parts can potentially increase downtime for the fuel cell 

buses. Ballard carefully monitored the minimum/maximum numbers of many high-cost 

parts for the fuel cell bus system. Many of these parts are produced by second-tier 

suppliers, making this a challenge. VTA and Ballard worked together to successfully 

minimize this potential downtime due to parts availability during the evaluation period. 

 35
• Hydrogen release: VTA restricted operation of the buses on several routes that traveled 

under a shopping mall and included a stop under the mall. The concern was the release 

of hydrogen (caused by a PRD) while at that location. 

VTA controls which drivers are assigned to operate the fuel cell buses rather than train all drivers 

at Cerone. The number of trained drivers started at two and has grown to more than 20. Based 

on several discussions with VTA staff, the following comments reflect impressions from VTA 

fuel cell bus drivers: 

• “Operating the fuel cell buses has been fun; the bus has smooth acceleration (probably 

because it’s heavier than a diesel bus).” 

• “I like the fact that it’s a new bus.” 

• “The bus is really quiet. The loudest noise is the air conditioning fan; it’s a lot quieter 

than the diesel buses.” 

• “I’m a little concerned about ‘hurting’ the bus.” 

• “The bus gets attention from the public while on the street.” 

• “The bus is a little slower from stop than a diesel bus, but it tops out at a higher speed.” 

• “The bus is a little top heavy. I can feel a little lean during turns.” 

• “The braking and retarder feel better than the diesel buses.” 

 36
Training and Public Awareness 

As previously mentioned, familiarization training for hydrogen safety and general characteristics 

was held at VTA for all staff at Cerone and for local emergency responders. Training groups 

included: 

• Bus operators 

• Bus technicians/mechanics 

• Cleaners 

• General personnel 

• Operations control center 

• Facility maintenance personnel 

• VTA emergency response personnel 

• Emergency responders outside of VTA. 

The VTA mechanics assigned to the fuel cell buses received training from Ballard on the fuel 

cell propulsion system and training from Air Products on the hydrogen dispensing station 

operation. The drivers of the fuel cell buses were also trained on vehicle systems and additional 

items on the pre-trip inspection sheet. VTA continues to provide familiarization training for 

emergency responders (fire and police). A quick reference card was produced for emergency 

responders showing the locations of specific equipment and places where it would be dangerous 

to cut into the bus. 

VTA accommodates requests for tours and brings the buses to events as time and resources 

allow. Such events, tours, and presentations include: 

• March 14, 2005: VTA hosted a tour for the Chinese Fuel Cell Bus program. 

• March 17, 2005: VTA participated in the Santa Clara Valley Science and Engineering 

Fair Association; one fuel cell bus was on display. 

• March 29, 2005: VTA hosted a tour of the hydrogen dispensing station for the 

Hazardous Materials Subcommittee of the Northern California Fire Prevention Officers. 

• April 21, 2005: VTA participated at San Jose State University’s Earth Day; one fuel cell 

bus was on display. 

• May 6, 2005: VTA and CaFCP made a presentation at a Santa Clara County Fuel Cell 

Working Group workshop. The group was given a ride in a fuel cell bus. 

• May 10-12, 2005: VTA provided training for Milpitas Fire Department with CaFCP; one 

of the fuel cell buses was used in the training. 

• May 24, 2005: VTA took a fuel cell bus to Sheppard Middle School as a community 

outreach event; 34 students and teachers took a ride on the bus. 

• June 1-2, 2005: VTA participated in United Nations World Environment Day in San 

Francisco by displaying the ZEB and providing related information. International VIPs, 

environmental experts, and media representatives rode the ZEB on pre-scheduled routes. 

• July 12, 2005: VTA hosted a tour for Ron Dodsworth, assistant general manager of 

Denver RTD, and several RTD board members at VTA’s Cerone Operations Division. 

 37
• July 14, 2005: VTA provided a ZEB presentation to the Risk and Insurance Management 

Society. 

• July 15, 2005: Representatives from DaimlerChrysler and Matt Nauman of the Mercury 

News visited VTA’s Cerone facility to fill a DaimlerChrysler fuel cell vehicle at the 

hydrogen fueling station. 

• September 30, 2005: Staff participated in the CaFCP Road Rally 2005 at San Jose State 

University. The ZEB was on display and program materials were provided to attendees. 

• September 30, 2005: The Road Rally caravan vehicles were fueled at VTA’s hydrogen 

fueling station. The media was invited to attend. 

• September 30, 2005: Staff participated in the Road Rally VIP event at the Doubletree 

Hotel in San Jose. The ZEB was on display and program materials were provided to 

attendees. 

• October 4, 2005: VTA hosted a tour for representatives of the Swedish Broadcasting 

Company who visited VTA's Cerone facility to learn about ZEBs. 

• October 26, 2005: Staff participated in the Fuel Cell Workshop at West Valley College 

in Saratoga, California. The ZEB was on display and program materials were provided to 

attendees. 

• November 2, 2005: Staff participated in the California Transit Association Conference 

by hosting the ZEB Technical Tour, which included a ride on the ZEB and a visit to the 

hydrogen fueling station and maintenance facility. VTA staff gave a presentation on the 

ZEB program and provided related materials. 

• November 8, 2005: VTA hosted a tour for Emilio Hoffmann, director of Brazil H2 Fuel 

Cell Energy, which is devoted to spreading information on the hydrogen and fuel cell 

economy in Brazil. 

• November 9, 2005: VTA hosted a tour for Nick Bagly of "Drive Around the World." 

Bagly visited VTA's Cerone facility to learn about ZEBs. 

• February 27, 2006: VTA hosted fire fighter training for the San Jose Fire Department. 

The training provided a refresher to a number of fire fighters and familiarization to others 

recently assigned to local departments. Ballard and Air Products personnel were also on 

hand to answer questions. 

• March 8, 2006: VTA hosted a tour and presentation for BC Transit. The transit agency 

is gathering information on FCBs as they prepare to procure and operate up to 20 FCBs 

in the Vancouver/Whistler area in time for the 2010 Winter Olympics. 

• March 13, 2006: VTA hosted a visit by “Drive Around the World” as they prepared for a 

trip to the South Pole using a fuel cell Hummer. The team took pictures of the ZEB and 

fuel cell systems and discussed the design plans for the fuel cell vehicle. 

• March 23, 2006: A GMC fuel cell vehicle and a Marine Corps fuel cell truck were fueled 

at the VTA station. 

• April 22, 2006: VTA provided a ZEB for display during President Bush’s visit to the 

California Fuel Cell Partnership. 

• April 18, 2006: VTA staff participated in Earth Day celebration at San Jose State 

University. 

• May 24, 2006: VTA staff participated in the official opening of Highway 85 and 1.01 

interchange. A ZEB was used for shuttle service and display. 

• June 6, 2006: VTA hosted a tour and presentation for Air Products Management. 

 38
• June 8, 2006: VTA staff provided a ZEB progress report and tour to the Technical 

Advisory Committee to the VTA board. 

• July 13, 2006: VTA hosted a tour for representatives from the Mineta Institute for 

Transportation. 

• August 9, 2006: VTA hosted a tour for Transmetics. 

• August 29, 2006: VTA hosted a tour and bus review for the Federal Motor Carrier Safety 

Administration. 

• October 10, 2006: VTA hosted a tour for participants at the APTA Annual Meeting in 

San Jose. 

• October 10, 2006: VTA hosted a tour for EU delegates, former Secretary Norman 

Mineta, Mayor Gonzales, EU Ambassador Angelos Pangratis, and other dignitaries. 

 39
Evaluation Results 

In this evaluation, the starting point was chosen by VTA as February 28, 2005, the day that the 

agency’s fuel cell buses first went into extra revenue service from the Cerone Operating 

Division. This report provides analysis and discussion focused on a data period including March 

2005 through July 2006. Some results and discussion presented in this report include 

information and data results prior to March 2005. The data period used is provided in each case. 

In this evaluation, the fuel cell buses at VTA are considered prototype technology, and the 

analysis and comparison discussions with standard diesel buses reflects this status. The intent of 

this analysis is to determine the status of this implementation and improvements that have been 

made over time at VTA. There is no intent to consider this implementation of fuel cell buses as 

commercial (or full revenue transit service). The evaluation focuses on documenting progress 

and opportunities for improvement of the vehicles, infrastructure, and procedures. 

Route Descriptions 

VTA operates 71 fixed bus routes, 11 of which are express service. VTA also operates one bus 

rapid transit line and 14 shuttle service routes. Cerone is one of three bus operating divisions at 

VTA and provides 140 buses for standard weekday service. The weekly average mileage and 

speed for buses operating from Cerone is shown in Table 8. All standard buses at Cerone are 

randomly dispatched on routes. 

Table 8. Summary of Total Weekly Bus Usage from Cerone 

Day of Week Total Miles Hours Avg. Speed 

Weekday 22,061 1,527 14.4 

Saturday 11,294 776 14.6 

Sunday 9,600 667 14.4 

Weekly Total 131,200 9,078 14.5 

 

For demonstrating this advanced technology, the fleet chose to use the three fuel cell buses for 

“extra” service on existing routes, meaning they are placed on routes between two regularly 

scheduled buses. This is meant to prevent a situation where passengers are stranded for a long 

time in the event of a fuel cell bus failure. The three fuel cell buses are operated during peak 

weekday hours with two buses in service and one as a spare. This allows for service 

interruptions if a bus needs maintenance or is scheduled for a public event. VTA also limits the 

use of the buses to times when a trained ZEB mechanic is available. 

The scheduling department created two blocks of work for the fuel cell buses. These blocks 

have changed over time to enable the fuel cell buses to operate on several VTA routes and 

experience different types of operation. VTA’s strategy for testing the overall bus performance 

was to select shorter routes close to the Cerone base to start and gradually introduce the buses to 

longer routes that cover more ground. A summary of these assignments is shown in Table 9. 

The fuel cell buses have generally been used at an average speed (approximately 12.6 mph 

during the evaluation period) that is slightly less than the fleet average for the diesel buses at 

Cerone. 

 40
Table 9. Route Block Assignments for the Fuel Cell Buses 

Routes Pull Out 

Time 

Pull In 

Time 

Total 

Time 

Total 

Miles 

Average 

Speed 

32 8:00 a.m. 2:21 p.m. 6:21 85.5 13.5 

33 8:00 a.m. 2:30 p.m. 6:30 86.5 13.3 

45 8:03 a.m. 2:00 p.m. 5:57 52.0 8.7 

46 8:00 a.m. 2:23 p.m. 6:23 84.0 13.2 

47 8:00 a.m. 2:14 p.m. 6:14 71.5 11.5 

53 8:00 a.m. 2:22 p.m. 6:22 61.0 9.6 

62 6:42 a.m. 2:23 p.m. 7:41 88.0 11.5 

102/22/71 6:42 a.m. 2:27 p.m. 7:45 114.7 14.8 

Bus Use and Availability 

Bus use and availability are indicators of reliability. The lack of bus usage may be an indication 

of downtime for maintenance or purposeful reduction of planned work for the buses. This 

section provides a summary of bus usage and availability for the two study groups of buses. 

Figure 15 shows mileage and fuel cell system operating hour accumulation from the start of 

hydrogen fueling in November 2004 through July 2006. As would be expected, usage began to 

accumulate faster after the buses went into revenue service at the end of February 2005. Use of 

the fuel cell buses was limited to weekdays and extra service within an 8-hour shift. Other 

limiting factors included maintenance issues and the availability of trained drivers and mechanics 

for the fuel cell buses. 

Table 10 summarizes average monthly mileage accumulation by bus and study group for the 

evaluation period. The three fuel cell buses accumulated 40,429 miles in the 17-month 

evaluation period and 3,219 hours on the fuel cell systems. This equates to an average operating 

speed for the fuel cell buses of 12.6 mph, which is slightly slower than the overall (diesel bus) 

average speed for Cerone buses (14.5 mph). Average monthly mileage per fuel cell bus was 809 

miles during the evaluation period. 

The diesel study buses were operated in normal VTA service from Cerone, including weekend 

operation. The average monthly mileage per bus during the evaluation period was 4,335 miles. 

In calendar year 2004, these five buses had an average monthly mileage per bus of 4,027 miles; 

however, bus 2230 was out of service for significant maintenance. With bus 2230 removed from 

this average, the diesel buses had an average monthly mileage per bus of 4,273 miles, which is 

similar to that experienced during the evaluation period. 

 41
0

10,000

20,000

30,000

40,000

50,000

60,000

Nov-04

Dec-04

Jan-05

Feb-05

Mar-05

Apr-05

May-05

Jun-05

Jul-05

Aug-05

Sep-05

Oct-05

Nov-05

Dec-05

Jan-06

Feb-06

Mar-06

Apr-06

May-06

Jun-06

Jul-06

Miles

0

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

FC Hours

Cumulative Miles Cumulative Fuel Cell Hours

Figure 15. Cumulative mileage and fuel cell hours for three fuel cell buses 

Table 10. Average Monthly Mileage (Evaluation Period) 

Bus Starting 

Hubodometer 

Ending 

Hubodometer 

Total 

Mileage Months Monthly Average 

Mileage 

Fuel Cell 

System Hours 

4001 7,930 21,469 13,539 17 796 1,109 

4002 959 14,514 13,560 16 848 1,075 

4003 954 14,284 13,330 17 784 1,035 

Fuel Cell 40,429 50 809 3,219 

2229 134,738 203,719 72,275 17 4,251 N/A 

2230 115,857 191,778 75,921 17 4,466 N/A 

2231 130,452 205,917 77,688 17 4,570 N/A 

2232 122,086 195,148 73,062 17 4,298 N/A 

2233 134,142 203,690 69,548 17 4,091 N/A 

Diesel 368,494 85 4,335 N/A 

Availability of a diesel bus was measured by the number of days it might be scheduled for 

service and the number of days it was unavailable for service due to any maintenance issues 

(weekends were included in the calculation). During the evaluation period, the diesel buses had 

an availability rate of 85%. VTA’s goal is 80% for diesel buses. 

During the evaluation period, the fuel cell buses had an availability rate of 58% for each 

weekday, with a goal of 67%. VTA’s schedule was designed for two of the three fuel cell buses 

to be in service on weekdays, except holidays. This would generally indicate that the fuel cell 

buses met the goal 87% of the time. Figure 16 shows monthly average availability for the fuel 

cell buses. Figure 17 shows a breakdown of the general causes of the fuel cell buses being 

unavailable for service. As shown in Figure 16, the fuel cell buses met (or nearly met) the VTA 

availability target of 67% during seven of the 16 evaluation months. Each of the fuel cell buses 

 42
had a similar availability rate, which averaged between 57% and 59% during the evaluation 

period. This is an indication of VTA’s intent to use all three fuel cell buses in a similar manner 

and as much as possible. 

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Mar-05

Apr-05

May-05

Jun-05

Jul-05

Aug-05

Sep-05

Oct-05

Nov-05

Dec-05

Jan-06

Feb-06

Mar-06

Apr-06

May-06

Jun-06

Jul-06

Percent (%) Availability

VTA FCB Availabililty Target 

Figure 16. Fuel cell bus monthly average availability 

Propulsion

Non-Propulsion 65%

4%

Roadcalls

9%

Preventive 

Maintenance

22%

Figure 17. Breakdown of causes for fuel cell buses being unavailable for service 

 43
Fuel Economy and Cost 

As previously mentioned, hydrogen fuel was trucked as a liquid from near Sacramento, 

California, to San Jose and added to the fuel dispensing station at Cerone. For trucking 

commerce, the liquid hydrogen was tracked as mass (kg) of fuel delivered to the hydrogen 

dispensing station. Fueling records for the fuel cell buses were tracked as mass (kg) of hydrogen 

dispensed for each fuel fill. To compare the hydrogen fuel dispensed and fuel economy to diesel, 

the hydrogen dispensed was also calculated into diesel energy equivalent gallons. The general 

energy conversions used in this report are shown at the end of the Appendix. 

Table 11 shows hydrogen and diesel fuel consumption and fuel economy for the two study 

groups during the evaluation period. The fuel cell buses averaged 3.12 miles per kg of hydrogen, 

which translates into 3.52 miles per diesel equivalent gallon (mpg). This fuel economy includes 

all hydrogen fuel added to the buses even if there was some venting for maintenance or testing 

during the evaluation period. The diesel study group had a fuel economy of 3.98 mpg. With 

diesel as the baseline, the fuel cell buses had a fuel economy that was 12% lower on an energy 

equivalent basis (note that these fuel cell buses do not use a hybrid propulsion configuration). 

Figure 18 shows average monthly energy equivalent fuel economies throughout the evaluation 

period for the fuel cell and diesel buses. 

Table 11. Fuel Use and Economy (Evaluation Period) 

Bus Mileage 

(Fuel Base) 

Hydrogen 

(kg) 

Miles per 

kg 

Diesel Equivalent 

Amount (Gallon) 

Miles per 

Gallon 

4001 13,539 4,528 2.99 4,007 3.38 

4002 13,339 4,232 3.15 3,745 3.56 

4003 13,330 4,144 3.22 3,668 3.63 

Fuel Cell 40,208 12,904 3.12 11,420 3.52 

2229 67,717 16,762 4.04 

2230 75,760 19,329 3.92 

2231 74,360 18,444 4.03 

2232 73,062 18,751 3.90 

2233 69,548 17,217 4.04 

Diesel 360,447 90,503 3.98 

As reported earlier, the average cost of hydrogen during the evaluation period was $9.06 per kg 

of hydrogen and the average cost of diesel fuel was $2.07 per gallon. These average fuel costs 

translate into a fuel cost per mile of $2.91 for the fuel cell buses and $0.52 per mile for the diesel 

buses. If hydrogen fuel losses at the station are taken into account, the fuel cost per mile for the 

fuel cell buses would essentially double. 

 44
0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

4.50

Mar-05

Apr-05

May-05

Jun-05

Jul-05

Aug-05

Sep-05

Oct-05

Nov-05

Dec-05

Jan-06

Feb-06

Mar-06

Apr-06

May-06

Jun-06

Jul-06

Miles per Gallon (Diesel Equivalent)

Fuel Cell Bus Diesel Bus

Figure 18. Average fuel economy (mpg) by month 

Maintenance Analysis 

The maintenance cost analysis in this section is only for the evaluation period (March 2005 

through July 2006) for the two study groups of buses. Warranty costs are not included in the 

cost-per-mile calculations, but are shown separately. All work orders for the study buses were 

collected and analyzed for this evaluation. The labor rate for maintenance was kept at a constant 

$50 per hour; this is not reflective of an average rate at VTA. This section first covers total 

maintenance costs, then maintenance costs broken down by bus system. 

Total Maintenance Costs—Total maintenance costs include the price of parts and hourly labor 

rates of $50 per hour; they do not include warranty costs. Cost per mile is calculated as follows: 

 Cost per mile = ((labor hours * 50) + parts cost) / mileage 

Table 12 shows total maintenance costs for the fuel cell and diesel buses. Warranty costs are 

shown in the table, but not included in the cost-per-mile calculation shown. For the fuel cell 

buses, bus 4001 has the lowest cost per mile and the other two have similar costs per mile. This 

most likely occurred because of the testing and shakedown of bus 4001 done at Ballard before 

the bus was delivered to VTA. The other two buses have had ongoing work to sort out 

integration issues. The warranty cost by bus also supports this hypothesis. 

Bus 4002 had some significant repairs on the fuel cell modules and fuel system in September 

2005 and October 2005. This bus had lower mileage than the other two because of these 

ongoing troubleshooting activities; however, since then, bus 4002 has had usage increased up to 

the same level as the other two for the evaluation period. The overall average maintenance cost 

per mile for the fuel cell buses was $3.55. 

 45
Table 12. Total Maintenance Costs (Evaluation Period) 

Bus Mileage Warranty 

Parts ($) Parts ($) Labor 

Hours 

Cost per 

Mile ($) 

4001 13,539 96,128.21 295.61 832.2 3.10 

4002 13,560 190,566.36 1,179.43 986.3 3.72 

4003 13,330 250,767.74 183.14 1,018.9 3.84 

Total Fuel Cell 40,429 537,462.31 1,658.18 2,837.4 3.55 

Avg. per Bus 13,476 179,154.10 552.73 945.8 -- 

2229 72,275 1,238.75 12,359.35 669.7 0.63 

2230 75,921 7,156.86 9,705.95 540.3 0.48 

2231 77,688 1,981.25 11,414.94 536.5 0.49 

2232 73,062 3,909.44 11,919.28 541.8 0.53 

2233 69,548 1,059.14 13,202.74 540.8 0.58 

Total Diesel 368,494 15,345.14 58,602.26 2,829.1 0.54 

Avg. per Bus 73,699 3,069.03 11,720.45 565.8 -- 

Warranty costs listed are those that were available for the data collection and evaluation. 

Warranty parts costs for the fuel cell propulsion systems were expected to be expensive 

(compared to mature diesel technology) because of the developmental nature of the technology 

and relatively low volume production of these systems. Figure 19 shows monthly total warranty 

costs for parts over the evaluation period. The three peaks (October 2005, April 2006, and June 

2006) in this chart are almost entirely costs for replacing fuel cell rows. This will be discussed 

more in the propulsion-related maintenance section below. VTA reports that some of the 

warranty parts costs may not be accounted for in this chart, but the vast majority are. 

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

160,000

Mar-05

Apr-05

May-05

Jun-05

Jul-05

Aug-05

Sep-05

Oct-05

Nov-05

Dec-05

Jan-06

Feb-06

Mar-06

Apr-06

May-06

Jun-06

Jul-06

Warranty Parts Cost ($)

Figure 19. Monthly total warranty parts costs ($) for fuel cell buses (evaluation period) 

 46
The diesel buses had similar maintenance costs per mile for four of the five buses. The overall 

average maintenance cost per mile for the diesel group was $0.54. Bus 2229 had a slightly 

higher maintenance cost, which was caused by major repairs for the transmission, air 

compressor, and exhaust systems. 

The total maintenance costs, without warranty costs, are much lower for the diesel buses. The 

per-bus results for the fuel cell buses compared to the diesel buses are as follows: 

• Usage/Mileage – 82% lower 

• Warranty Parts Costs – much higher 

• Parts Costs – 95% lower (many parts costs covered in warranty for fuel cell buses) 

• Labor Hours – 67% higher 

• Cost per Mile (without warranty costs) – 6.6 times higher. 

This reflects the stage of development for the fuel cell buses and the fact that they are in the 

prototype development stage for transit bus service. 

Maintenance Cost Broken Down by System—Table 13 shows maintenance costs by vehicle 

system and bus study group (without warranty costs included). The vehicle systems shown in 

the table include the following: 

• Cab, Body, and Accessories: Includes body, glass, and paint repairs following accidents; 

cab and sheet metal repairs on seats and doors; and accessory repairs such as 

hubodometers and radios 

• Propulsion-Related Systems: Repairs for exhaust, fuel, engine, electric motors, fuel cell 

modules, propulsion control, non-lighting electrical (charging, cranking, and ignition), air 

intake, cooling, and transmission 

• Preventive Maintenance Inspections (PMI): Labor for inspections during preventive 

maintenance 

• Brakes 

• Frame, Steering, and Suspension 

• Heating, Ventilation, and Air Conditioning (HVAC) 

• Lighting 

• Air System, General 

• Axles, Wheels, and Drive Shaft 

• Tires.

The systems with the highest percentage of maintenance costs for the fuel cell buses were 

propulsion-related; PMI; and cab, body, and accessories. These three systems, along with the 

frame, steering, and suspension system, were also the highest maintenance cost systems for the 

diesel buses. The additional category of frame, steering, and suspension reflects the higher use 

of the diesel buses compared to the fuel cell buses. 

 47
Table 13. Breakdown of Vehicle System Maintenance Cost per Mile (Evaluation Period) 

Fuel Cell Diesel 

System Cost per 

Mile ($) 

Percent of 

Total (%) 

Cost per 

Mile ($) 

Percent of 

Total (%) 

Cab, Body, and 

Accessories 0.31 9 0.13 24 

Propulsion-Related 2.38 67 0.20 37 

PMI 0.61 17 0.09 16 

Brakes 0.06 2 0.02 4 

Frame, Steering, and 

Suspension 0.02 1 0.05 9 

HVAC 0.10 3 0.02 4 

Lighting 0.01 0 0.02 4 

Air, General 0.04 1 0.01 2 

Axles, Wheels, and 

Drive Shaft 0.01 0 0.00 0 

Tires 0.01 0 0.00 0 

Total 3.55 100 0.54 100 

Preventive maintenance for the fuel cell and diesel buses was nearly the same percent portion of 

total maintenance cost. The diesel buses have a preventive maintenance schedule of 6,000 miles. 

The fuel cell buses have preventive maintenance inspections scheduled for 160 hours and 320 

hours based on fuel cell module operation, and every 3,700 miles (7,500 miles and 15,000 miles) 

for coach and drive train components based on bus operation in addition to the 6,000 mile 

interval for the remainder of the bus. These preventive maintenance schedules for the fuel cell 

buses do not necessarily overlap. At times, the fuel cell buses may be in for preventive 

maintenance for one schedule one week and another the following week. The mileage-based 

schedules were essentially converted from the European schedules that were based on 

kilometers. Ballard has been working to harmonize these mileage and fuel cell system hour PM 

schedules. A daily pre-trip inspection of the ZEBs is also required by maintenance personnel. 

Propulsion-Related Maintenance Costs—The propulsion-related vehicle systems include the 

exhaust, fuel, engine, electric propulsion, air intake, cooling, non-lighting electrical, and 

transmission systems. Table 14 shows a breakdown of the propulsion-related system repairs for 

the two study groups during the evaluation period (no warranty costs). The fuel cell buses had 

significantly higher maintenance costs for all of the systems shown in the table except for the 

exhaust and transmission systems. 

Several maintenance issues for the fuel cell buses arose during the evaluation period. The major 

issues are listed below with some comments as to resolution. All parts replacements discussed 

here were covered under warranty; only mechanic labor for these repairs is included in the 

maintenance cost analysis. 

• Fuel cell row replacement – There were a total of 15 fuel cell row replacements on the 

three buses during the evaluation period. For reference, there are six fuel cell rows in 

each of the two fuel cell modules on each bus. The cell rows required replacements due 

to low output voltage of a number of individual cells. These replacements were typically 

due to single cell issues within the row caused by blockage/contaminants. According to 

Ballard, the cell rows required repair, but did not indicate end of life failure. 

 48
• Sensor for air intake pressure differentiation – There were several failures early on 

because of a specification issue. This problem continues, but at a much lower rate of 

failure. 

Table 14. Propulsion-Related Maintenance Costs by System (Evaluation Period) 

Maintenance System Costs Fuel Cell Diesel 

Mileage 40,429 368,494 

Total Propulsion-Related Systems (Roll-up) 

Parts cost ($) 243.23 26,538.65 

Labor hours 1914.8 969.8 

Total cost ($) 95,983.23 75,030.15 

Total cost ($) per mile 2.37 0.20 

Exhaust System Repairs 

Parts cost ($) 0.00 7,079.25 

Labor hours 0.0 275.3 

Total cost ($) 0.00 20,844.75 

Total cost ($) per mile 0.00 0.06 

Fuel System Repairs 

Parts cost ($) 0.00 3,469.40 

Labor hours 385.6 44.6 

Total cost ($) 19,280.00 5,696.90 

Total cost ($) per mile 0.48 0.02 

Engine System Repairs 

Parts cost ($) 151.34 6,585.60 

Labor hours 691.7 268.0 

Total cost ($) 34,736.34 19,983.60 

Total cost ($) per mile 0.86 0.05 

Electric Motor and Fuel Cell Module Repairs 

Parts cost ($) 0.00 0.00 

Labor hours 267.2 0.0 

Total cost ($) 13,360.00 0.00 

Total cost ($) per mile 0.33 0.000 

Non-Lighting Electrical System Repairs (General Electrical, Charging, 

Cranking, Ignition) 

Parts cost ($) 1.50 1,691.77 

Labor hours 188.1 82.4 

Total cost ($) 9,406.50 5,811.77 

Total cost ($) per mile 0.23 0.02 

Air Intake System Repairs 

Parts cost ($) 0.00 845.14 

Labor hours 153.8 4.1 

Total cost ($) 7,690.00 1,050.14 

Total cost ($) per mile 0.19 0.00 

Cooling System Repairs 

Parts cost ($) 0.00 3,988.62 

Labor hours 200.4 174.6 

Total cost ($) 10,020.00 12,716.12 

Total cost ($) per mile 0.25 0.03 

Transmission Repairs 

Parts cost ($) 90.44 2,878.87 

Labor hours 26.0 120.6 

Total cost ($) 1.390.44 8,906.87 

Total cost ($) per mile 0.03 0.02 

 49
• CVM board – This board is used to monitor each fuel cell within the modules. There is 

one board for each of the six fuel cell rows as well as a master board. Several early 

failures of this board were due to moisture getting into the board and components. This 

has essentially been resolved by using a different sealant coating for the boards. 

• Coolant (glycol and deionized water) level switch – The coolant reservoir is on the roof 

of the bus and there is a level switch to monitor the amount of coolant. This switch was 

problematic during the evaluation period with several failures, but appeared to be 

essentially resolved after November 2005. 

• Fuel system regulator – This is the main fuel pressure regulator to take the high pressure 

hydrogen from storage down to working pressure for the fuel cells. There were some 

issues of contaminants causing the needle and seat design to not reseat in some cases. 

The manufacturer provided a redesign that appeared to be working before the end of the 

evaluation period. 

• Pressure relief devices and solenoid valves – These are devices that were used as part 

of the fuel storage system. There were several failures reported because of contaminants 

and quality control issues with the assembly of the components. This was resolved on the 

first replacement. 

• Hydrogen sensors – There are two types of sensors on the buses—one type in the fuel 

cell modules and one type in the rest of the bus, most of which were located in the engine 

compartment. The fuel cell module hydrogen sensors were replaced by an upgraded part 

about half way through the program. There were some failures of the hydrogen sensors 

in the rest of the coach. The main issue for failures of both types of sensors was 

contamination over time. 

• Power inverters – There were 12 inverter failures during the evaluation period. Most of 

the failures were due to high heat exposure. This was resolved by changing the amount 

of coolant flow and by lowering the coolant temperature. There were also some 

connector issues that caused a few of the failures. 

Roadcall Analysis 

A roadcall (RC) or revenue vehicle system failure (as named for the National Transit Database4) 

is defined as a failure of an in-service bus that causes the bus to be replaced on route or causes a 

significant delay in schedule. If the problem with the bus can be repaired during a layover and 

the schedule is kept, this is not considered a RC. The analysis provided here only includes RCs 

that were caused by “chargeable” failures. Chargeable RCs include systems that can physically 

disable the bus from operating on route, such as interlocks (doors), engine, etc. They do not 

include RCs for things such as radios or destination signs. 

Table 15 shows the RCs and miles between roadcalls (MBRC) for each study bus and breaks 

them down by all RCs and propulsion-related-only RCs. The diesel buses have much better 

MBRC rates for both categories. This is indicative of the low usage and prototype status of the 

fuel cell buses. 

 

4

 Revenue vehicle system failures are defined for the FTA’s National Transit Database in the Reporting Manual, 

Resource Module, which can be found at 

www.ntdprogram.com/NTD/ReportingManual/2005/Annual/PDFFiles/2005%20Resource%20Module.pdf. 

 50
Table 15. Roadcalls and MBRC (Evaluation Period) 

Bus Mileage All 

Roadcalls All MBRC Propulsion 

Roadcalls 

Propulsion 

MBRC 

4001 13,539 16 846 16 846 

4002 13,560 17 798 16 848 

4003 13,330 12 1,111 12 1,111 

Fuel Cell 40,429 45 898 44 919 

2229 72,275 8 9,034 7 10,325 

2230 75,921 8 9,490 8 9,490 

2231 77,688 8 9,711 3 25,896 

2232 73,062 9 8,118 9 8,118 

2233 69,548 12 5,796 7 9,935 

Diesel 368,494 45 8,189 34 10,838 

 51
Demonstration Achievements and Challenges 

This section summarizes some of the achievements and challenges encountered during the twoyear VTA fuel cell bus demonstration program through July 2006. 

Achievements 

VTA and SamTrans teamed up to successfully fund, design, and complete a full scale 

demonstration of fuel cell buses as part of a two-year program with 17 months of extra revenue 

service at VTA (March 2005 through July 2006). This program involved the purchase of three 

40-foot fuel cell buses (Gillig buses with Ballard fuel cell propulsion) for $14.1 million, 

including a two-year warranty, parts, training, and service from Ballard and Gillig. A hydrogen 

dispensing station was designed, constructed, and operated on site by Air Products at VTA’s 

Cerone bus operating division. Additionally, a new, stand-alone maintenance facility was 

designed, constructed, and operated as well as a new bus wash to accommodate the taller fuel 

cell buses and the hydrogen fuel onboard the buses. Construction and operating costs were $4.4 

million for all three facilities. VTA reported excellent management and union support for this 

fuel cell bus demonstration program. 

Hydrogen Fueling – 31,836 kg of liquid hydrogen were delivered to the hydrogen fueling 

station. 14,024 kg of gaseous hydrogen were dispensed into buses at up to 5,000 psi (460 

hydrogen fuelings). During the 17-month evaluation period, the hydrogen dispensing station 

provided overall average fills at 16 minutes, 30.9 kg/fill, and 1.93 kg/min. 

Fuel Cell Buses – The three fuel cell buses were operated in extra revenue service for 17 

months. This operation accumulated 40,429 total miles and 3,219 total hours of operation. This 

indicated an average operating speed of 12.6 mph. Fuel cell buses achieved a 3.52 miles per 

diesel energy equivalent gallon fuel efficiency during the evaluation period. 

Bus Operations – Two VTA mechanics were fully trained by Ballard to work on the fuel cell 

buses. Ballard also provided a technician during the warranty period (up to July 2006). The two 

VTA fuel cell bus mechanics completed all fuel cell bus inspections, cleanings, fuelings, and 

maintenance, including repairs (along with the Ballard technician). The fuel cell bus mechanics 

entered all work orders to assure proper tracking of work performed. They also maintained 

communication with Ballard personnel to assure data on the buses was maintained. The VTA 

fuel cell bus mechanics provided support to Ballard for troubleshooting the bus propulsion 

systems and to Air Products for troubleshooting the hydrogen dispensing station. The VTA fuel 

cell bus mechanics also kept the drivers informed of potential conditions that could occur with 

the fuel cell buses. All public events that the fuel cell buses were a part of required the presence 

of a VTA fuel cell bus mechanic. Operation of the fuel cell buses was kept to weekday service 

during normal working hours to ensure that a fuel cell bus mechanic could be available for any 

potential issues. 

 52
Challenges 

The main challenges for this fuel cell bus demonstration at VTA were extremely high capital and 

operating costs, a need for standardized hydrogen building codes, hydrogen fuel cost, and 

reliability of the fuel cell buses. 

Capital Costs – This fuel cell bus program required $14.1 million for the fuel cell buses and the 

warranty and support package. The facilities additions (hydrogen dispensing, maintenance, and 

bus wash) were an additional $4.4 million. 

Bus Operating Costs – The current cost to operate these prototype fuel cell buses is still 

extremely high, making it difficult for most transit agencies to participate in demonstrations (fuel 

and maintenance costs for fuel cell buses is $6.46 per mile; diesel comparison buses cost $1.06 

per mile). More research is needed to investigate ways to reduce the cost. 

Fuel Economy – The fuel cell buses had a fuel economy 12% lower than the diesel comparison 

buses. The fuel cell buses had an electric drive train, but did not incorporate a hybrid propulsion 

system design, which would have increased the fuel economy. 

Hydrogen Fuel Cost – For this demonstration project, the hydrogen fuel dispensing station was 

sized for the operation of six fuel cell buses; however, only three fuel cell buses were operated. 

This sizing difference caused a higher level of the hydrogen fuel to be vented during the 

evaluation period than was anticipated. Additionally, the prototype compressor was also 

designed to reduce hydrogen venting; however, due to its lack of operation, this benefit could not 

be verified. The average hydrogen fuel delivery cost (trucking liquid hydrogen from Sacramento 

to San Jose) is $9.06 per kg of hydrogen, but with the venting taken into account, this cost is 

actually $18.12 per kg when placed into the buses. 

Fuel Cell Bus Reliability – Diesel buses in VTA service (and in most transit fleets) are often 

operated in excess of 12 hours per day, seven days per week with an average usage of 4,000 

monthly miles per bus, an availability rate of 85%, and a roadcall rate of over 5,000 miles 

between roadcalls. The VTA diesel comparison buses achieved more than 4,000 monthly miles 

per bus, an availability rate of 85%, and over 8,000 miles between roadcalls during the 

evaluation period. During this evaluation, the fuel cell buses operated only eight hours per day, 

five days per week, and achieved only 800 monthly miles per bus with an availability rate of 

58% (which was lower than the target availability rate of 67%). The fuel cell bus roadcall rate 

was only 900 miles between roadcalls. While the fuel cell buses did have significant operation, 

this technology does not yet come close to meeting standard transit bus operating expectations. 

Manufacturers need to work with transit agencies to further improve the technology to meet 

industry standards and expectations. 

Consistent Maintenance Practices – Fuel cell buses have preventive maintenance (PM) 

schedules that are tracked by mileage as well as hours. Because the different PM schedules do 

not often overlap, proper maintenance of these buses requires more downtime than a 

conventional bus. This downtime could be lessened by optimizing the various PM schedules to 

coincide with standard PM schedules. Specific PMs for fuel cell buses also require staff to 

remove large components to perform checks and maintenance. This can be time consuming and 

 53
result in even more downtime for the bus. Manufacturers should work closely with the transit 

industry to design the next generation systems and components for optimal ease and speed of 

maintenance. 

Hydrogen Use Infrastructure and Building Codes – Hydrogen manufacturers and other 

interested parties need to continue work to standardize hydrogen building codes and provide 

familiarization for the authorities with jurisdiction in locations where hydrogen infrastructure is 

planned. This lack of hydrogen familiarity was made even worse by the number of false alarms 

as the hydrogen dispending station was being tested. False alarms at the hydrogen station and 

maintenance facility caused shutdowns, resulted in delayed or lost service, and created concern 

by the local emergency responders regarding the operational safety of this equipment. Many of 

the alarms at VTA could have been prevented with good system design and by providing the onsite staff with a clear understanding of how the system and components worked. Station and fuel 

providers should work closely with transit agency partners to rectify the issues and reduce the 

potential for false alarms that impact the operation of the depot. 

Extreme Pressure for Implementation – In California, there is extreme pressure to speed up 

the introduction of zero emission vehicles because of serious air quality challenges. This 

pressure needs to match the ability of new and experimental hydrogen and fuel cell propulsion 

systems for the transit industry. Based on the results of this demonstration, much more work 

(research and optimization) is needed before these technologies are ready for full-scale 

implementation. However, the way to accomplish this needed research and optimization is to 

support such research and continue to field test new and advanced zero emission propulsion 

technologies. 

 54
What’s Next for this Demonstration? 

This report covers VTA operation of the fuel cell buses through July 2006. This is the end of the 

two-year demonstration and the warranty/support period for the fuel cell buses, as defined by 

Ballard. VTA has continued to run the fuel cell buses beyond July 2006 and is paying for 

support by Ballard and parts on a month-to-month basis. VTA currently intends to attempt 

another full year of service; however, additional funding and level of support from Ballard and 

Air Products have not yet been finalized. 

There are ongoing discussions between VTA and Ballard to potentially upgrade the existing fuel 

cell buses to a hybrid propulsion system and Ballard’s newer model fuel cell modules. Issues yet 

to be resolved in these discussions include funding requirements and sources as well as 

expectations and design of operations for these new hybrid fuel cell buses. 

VTA’s current lease of the hydrogen fuel dispensing station runs through May 2007 with two 

one-year options available from Air Products. Continuation beyond this would require 

renegotiation of the lease rates with Air Products. Air Products indicates that it intends to 

support the station and continue its testing and development activities. 

Ballard intends to continue to be a supplier of fuel cell power plants to vehicle manufacturers. It 

also has a new model fuel cell module for transportation applications. Ballard plans to have a 

potentially commercial fuel cell module product for the 2010-2015 timeframe. 

 55
Contacts 

DOE 

1000 Independence Ave., SW 

Washington, DC 20585 

Sigmund Gronich 

Technology Validation Manager 

Office of Hydrogen, Fuel Cells, and Infrastructure Technologies 

Phone: 202-586-1623 

E-mail: sigmund.gronich@ee.doe.gov

NREL 

1617 Cole Blvd. 

Golden, CO 80401 

Leslie Eudy 

Senior Project Leader 

Phone: 303-275-4412 

E-mail: leslie_eudy@nrel.gov 

VTA 

3331 N. 1st St. 

San Jose, CA 95134 

Art Douwes 

Senior Mechanical Engineer 

Phone: 408-321-7027 

E-mail: douwes@vta.org 

SamTrans 

301 N. Access Rd. 

South San Francisco, CA 94083-2727 

Kenneth Quijano 

Bus Maintenance 

Phone: 650-508-6418 

E-mail: quijanok@samtrans.com 

Ballard 

4343 N. Fraser Way 

Burnaby, BC V5J 5J9 

Canada 

 56
Byron Somerville 

Bus Program Manager 

Phone: 604-453-3889 

E-mail: byron.somerville@ballard.com

Air Products 

555 1st St., Ste. 302 

Benicia, CA 94510-3280 

Steve Hoffman 

Commercial Development 

Phone: 707-748-7595, ext. 15 

E-mail: hoffmasw@airproducts.com

Gillig Corporation 

25800 Clawiter Rd. 

Hayward, CA 94545 

Chuck Koske 

Vice President of Engineering 

Phone: 510-785-1500 

E-mail: chuck.koske@gillig.com

Battelle 

505 King Ave. 

Columbus, OH 43201 

Kevin Chandler 

Program Manager 

Phone: 614-424-5127 

E-mail: chandlek@battelle.org 

 57
Acronyms and Abbreviations 

APTA American Public Transportation Association 

BAAQMD Bay Area Air Quality Management District 

Btu British thermal units 

CaFCP California Fuel Cell Partnership 

CARB California Air Resources Board 

CEC California Energy Commission 

CUTE Clean Urban Transport for Europe 

DOE U.S. Department of Energy 

ECTOS Ecological City Transport System (Reykjavik, Iceland) 

E-stop Emergency stop 

FCB Fuel cell bus 

FTA Federal Transit Administration 

GVWR Gross vehicle weight rating 

HFCIT Hydrogen, Fuel Cells & Infrastructure Technologies 

HHICE Hybrid hydrogen internal combustion engine 

HVAC Heating, ventilation, and air conditioning 

in Inches 

JHFC Japan Hydrogen and Fuel Cell Demonstration Project 

kg Kilograms 

kW Kilowatt 

lb Pound 

lb-ft Pound feet 

LFL Lower flammability limit 

LHV Lower heating value 

MBRC Miles between roadcalls 

mpg Miles per gallon 

Nm Newton meter 

NREL National Renewable Energy Laboratory 

PAFC Phosphoric acid fuel cell 

PEM Proton exchange membrane 

PMI Preventive maintenance inspection 

ppm Parts per million 

psi Pounds per square inch 

RC Roadcalls 

rpm Revolutions per minute 

SamTrans San Mateo County Transit District 

STEP Sustainable Transport Energy for Perth 

UNDP-GEF United Nations Development Programme – Global Environment Facility 

UTC United Technologies Corporation 

VTA Santa Clara Valley Transportation Authority 

ZEB Zero emissions bus 

ZEbus Ballard zero emission bus 

 58
References and Related Reports 

NREL, 2005, VTA, SamTrans Look into Future with Bus Demo, National Renewable Energy 

Laboratory, Golden, CO, DOE/GO-102005-2147 

NREL, 2005, Draft Fuel Cell Transit Bus Evaluation Plan, National Renewable Energy 

Laboratory, Golden, CO 

EvoBus GmbH, 2004, Clean Urban Transport for Europe (CUTE), A Fuel Cell Bus Project in 

Nine European Cities, EvoBus, Ulm, Germany 

Chandler, K., Eudy, L., 2003, ThunderPower Bus Evaluation at SunLine Transit Agency, 

National Renewable Energy Laboratory, Golden, CO, DOE/GO-102003-1786 

NREL, 2003, SunLine Test Drives Hydrogen Bus, National Renewable Energy Laboratory, 

Golden, CO, DOE/GO-102003-1768 

NREL, 2002, General Evaluation Plan, Fleet Test & Evaluation Projects, National Renewable 

Energy Laboratory, Golden, CO, NREL/BR-540-32392 

College of the Desert, 2001, Hydrogen Fuel Cell Engines and Related Technologies (Course 

Materials, Modules 1-11), College of the Desert, Palm Desert, CA 

Eudy, L., Parish, R., Leonard, J., 2001, Hydrogen Fuel Cell Bus Evaluation (Ballard ZEbus), 

National Renewable Energy Laboratory, Golden, CO 

SunLine, 2001, Final Report, SunLine Transit Agency to Federal Transit Administration (Ballard 

ZEbus), SunLine Transit Agency, Thousand Palms, CA, Project Number CA-26-7022 

Xcellsis/Ballard, 2000, Cleaning Up: Zero-Emission Buses in Real-World Use, A Report on the 

Xcellsis/Ballard Phase 3 Fuel Cell Bus Program 

Other Reports from DOE/NREL Evaluations

Chandler, K, Walkowicz, K., 2006, King County Metro Transit Hybrid Articulated Buses: Final 

Evaluation Results, National Renewable Energy Laboratory, Golden, CO, NREL/TP-540-40585 

Chandler, K., Barnitt, R., 2006, New York City Transit (NYCT) Hybrid and CNG Transit Buses: 

Final Evaluation Results, National Renewable Energy Laboratory, Golden, CO, NREL/TP-540-

40125 

Barnitt, R., 2006, Case Study: Ebus Hybrid Electric Shuttle and Trolley Buses, National 

Renewable Energy Laboratory, Golden, CO, NREL/TP-540-38749 

 59
Chandler, K., Walkowicz, K., 2006, King County Metro Transit Hybrid Articulated Buses: 

Interim Evaluation Results, National Renewable Energy Laboratory, Golden, CO, NREL/TP540-39742 

Chandler, K., Eudy, L., Eberts, E., 2006, New York City Transit Hybrid and CNG Transit Buses: 

Interim Evaluation Results, National Renewable Energy Laboratory, Golden, CO, NREL/TP540-38843 

Chandler, K., 2006, Ten Years of Compressed Natural Gas (CNG) Operations at SunLine Transit 

Agency, National Renewable Energy Laboratory, Golden, CO, NREL/SR-540-39180 

NREL, 2005, Advanced Technology Vehicles in Service: New York City Transit Drives Hybrid 

Electric Buses into the Future, National Renewable Energy Laboratory, Golden, CO, DOE/GO102005-2009 

NREL, 2005, Advanced Technology Vehicles in Service, Knoxville Area Transit, National 

Renewable Energy Laboratory, Golden, CO, DOE/GO-102005-2085 

NREL, 2004, Advanced Technology Vehicles in Service, King County Metro Transit, National 

Renewable Energy Laboratory, Golden, CO, DOE/GO-102004-2026 

NREL, 2004, Advanced Technology Vehicles in Service, Indianapolis Public Transportation, 

National Renewable Energy Laboratory, Golden, CO, DOE/GO-102004-1986 

Chandler, K., Proc, K., 2004, Norcal Prototype LNG Truck Fleet, Final Results, National 

Renewable Energy Laboratory, Golden, CO, DOE/GO-102004-1920 

NREL, 2003, Advanced Technology Vehicles in Service: MTA New York City Transit, Diesel 

Hybrid Electric Buses, National Renewable Energy Laboratory, Golden, CO, NREL/FS-540-

33397 

Chandler, K., Vertin, K., Alleman, T., Clark, N., 2003, Ralphs Grocery Company EC-DieselTM

Truck Fleet: Final Results, National Renewable Energy Laboratory, Golden, CO, NREL/BR540-31363 

Eudy, L., Gifford, M., 2003, Challenges and Experiences with Electric Propulsion Transit Buses 

in the United States, National Renewable Energy Laboratory, Golden, CO, DOE/GO-102003-

1791 

NREL, 2002, Advanced Technology Vehicles in Service, Norcal Waste Systems, Inc., National 

Renewable Energy Laboratory, Golden, CO, NREL/FS-540-32808 

Chandler, K., Walkowicz, K., Eudy, L., 2002, New York City Transit Diesel Hybrid-Electric 

Buses: Final Results, National Renewable Energy Laboratory, Golden, CO, NREL/BR-540-

32427 

 60
Battelle/NREL, 2002, NYCT’s Diesel Hybrid-Electric Buses, Program Status Update, National 

Renewable Energy Laboratory, Golden, CO, NREL/BR-540-31668 

Eudy, L., 2002, Natural Gas in Transit Fleets: A Review of the Transit Experience, National 

Renewable Energy Laboratory, Golden, CO, NREL/TP-540-31479 

Battelle/NREL, 2001, Advanced Technology Vehicles in Service, Diesel Hybrid Electric Buses, 

National Renewable Energy Laboratory, Golden, CO, NREL/FS-540-30736 

Chandler, K., Norton, P., Clark, N., 2001, Waste Management’s LNG Truck Fleet, Final Results, 

National Renewable Energy Laboratory, Golden, CO, NREL/BR-540-29073 

Chandler, K., Norton, P., Clark, N., 2000, DART’s LNG Bus Fleet, Final Results, National 

Renewable Energy Laboratory, Golden, CO, NREL/BR-540-28739 

Chandler, K., Norton, P., Clark, N., 2000, Raley’s LNG Truck Fleet, Final Results, National 

Renewable Energy Laboratory, Golden, CO, NREL/BR-540-27678 

Battelle, 1999, Waste Management’s LNG Truck Fleet, Start-Up Experience, National 

Renewable Energy Laboratory, Golden, CO, NREL/BR-540-26617 

Battelle, 1997, Raley’s LNG Truck Fleet, Start-Up Experience, National Renewable Energy 

Laboratory, Golden, CO, NREL/BR-540-23402 

Battelle, 2000, DART’s LNG Bus Fleet, Start-Up Experience, National Renewable Energy 

Laboratory, Golden, CO, NREL/BR-540-28124 

Motta, R., Norton, P., Kelly, K., Chandler, K., Schumacher, L., Nigel, N., 1996, Alternative Fuel 

Transit Buses, Final Results from the National Renewable Energy Laboratory (NREL) Vehicle 

Evaluation Program, National Renewable Energy Laboratory, Golden, CO, NREL/TP-425-

20513 

 61
Appendix: Fleet Summary Statistics 

Fleet Summary Statistics: Santa Clara Valley Transportation Authority (VTA)

Diesel and FCB Study Groups 

Fleet Operations and Economics

Diesel Buses Fuel Cell Buses 

Number of Vehicles 5 3

Period Used for Fuel and Oil Op Analysis 3/05-7/06 3/05-7/06

Total Number of Months in Period 17 17

Fuel and Oil Analysis Base Fleet Mileage 360,447 40,208

Period Used for Maintenance Op Analysis 3/05-7/06 3/05-7/06

Total Number of Months in Period 17 17

Maintenance Analysis Base Fleet Mileage 368,494 40,429

Average Monthly Mileage per Vehicle 4,335 809

Availability 85% 58%

Fleet Fuel Usage in Diesel Gal/H2 kg 90,503 12,904

Roadcalls 45 45

RCs MBRC 8,189 898

Propulsion Roadcalls 34 44

Propulsion MBRC 10,838 918

 

Fleet Miles/kg Hydrogen 3.12

(1.13 kg H2/gal Diesel Fuel) 

Representative Fleet MPG (energy equiv.) 3.98 3.52

 

Hydrogen Cost per kg 9.06

Diesel Cost per Gallon 2.07 

Fuel Cost per Mile 0.52 2.91

 

Total Scheduled Repair Cost per Mile 0.12 0.70

Total Unscheduled Repair Cost per Mile 0.42 2.85

Total Maintenance Cost per Mile 0.54 3.55

 

Total Operating Cost per Mile 1.06 6.46

Maintenance Costs

 Diesel Buses Fuel Cell Buses 

Fleet Mileage 368,494 40,429

 

Total Parts Cost 58,602.26 1,658.18

Total Labor Hours 2829.1 2837.4

Average Labor Cost (@ $50.00 per hour) 141,455.00 141,870.00

 

Total Maintenance Cost 200,057.26 143,528.18

Total Maintenance Cost per Bus 40,011.45 47,842.73

Total Maintenance Cost per Mile 0.54 3.55

 62
Breakdown of Maintenance Costs by Vehicle System

Diesel Buses Fuel Cell Buses 

Fleet Mileage 368,494 40,429

 

Total Propulsion-Related Systems (ATA VMRS 27, 30, 31, 32, 33, 41, 42, 43, 44, 45, 65) 

Parts Cost 26,538.65 243.23

Labor Hours 969.8 1914.8

Average Labor Cost 48,491.50 95,740.00

Total Cost (for system) 75,030.15 95,983.23

Total Cost (for system) per Bus 15,006.03 31,994.41

Total Cost (for system) per Mile 0.20 2.37

 

Exhaust System Repairs (ATA VMRS 43) 

Parts Cost 7,079.25 0.00

Labor Hours 275.3 0.0

Average Labor Cost 13,765.50 0.00

Total Cost (for system) 20,844.75 0.00

Total Cost (for system) per Bus 4,168.95 0.00

Total Cost (for system) per Mile 0.06 0.00

 

Fuel System Repairs (ATA VMRS 44) 

Parts Cost 3,469.40 0.00

Labor Hours 44.6 385.6

Average Labor Cost 2,227..50 19,280.00

Total Cost (for system) 5,696.90 19,280.00

Total Cost (for system) per Bus 1,139.38 6,426.67

Total Cost (for system) per Mile 0.02 0.48

 

Power Plant (Engine) Repairs (ATA VMRS 45) 

Parts Cost 6,585.60 151.34

Labor Hours 268.0 691.7

Average Labor Cost 13,398.00 34,585.00

Total Cost (for system) 19,983.60 34,736.34

Total Cost (for system) per Bus 3,996.72 11,578.78

Total Cost (for system) per Mile 0.05 0.86

 

Electric Propulsion Repairs (ATA VMRS 46) 

Parts Cost 0.00 0.00

Labor Hours 0.0 267.2

Average Labor Cost 0.00 13,360.00

Total Cost (for system) 0.00 13,360.00

Total Cost (for system) per Bus 0.00 4,453.33

Total Cost (for system) per Mile 0.00 0.33

 

 63
Breakdown of Maintenance Costs by Vehicle System (continued)

 Diesel Buses Fuel Cell Buses 

Electrical System Repairs (ATA VMRS 30-Electrical General, 31-Charging, 32-Cranking, 33-

Ignition)

Parts Cost 1,691.77 1.50

Labor Hours 82.4 188.1

Average Labor Cost 4,120.00 9,405.00

Total Cost (for system) 5,811.77 9,406.50

Total Cost (for system) per Bus 1,162.35 3,135.50

Total Cost (for system) per Mile 0.02 0.23

 

Air Intake System Repairs (ATA VMRS 41) 

Parts Cost 845.14 0.00

Labor Hours 4.1 153.8

Average Labor Cost 205.00 7,690.00

Total Cost (for system) 1,050.14 7,690.00

Total Cost (for system) per Bus 210.03 2,563.33

Total Cost (for system) per Mile 0.00 0.19

 

Cooling System Repairs (ATA VMRS 42) 

Parts Cost 3,988.62 0.00

Labor Hours 174.6 200.4

Average Labor Cost 8,727.50 10,020.00

Total Cost (for system) 12,716.12 10,020.00

Total Cost (for system) per Bus 2,543.22 3,340.00

Total Cost (for system) per Mile 0.03 0.25

 

Hydraulic System Repairs (ATA VMRS 65) 

Parts Cost 0.00 0.00

Labor Hours 0.4 2.0

Average Labor Cost 20.00 100.00

Total Cost (for system) 20.00 100.00

Total Cost (for system) per Bus 4.00 33.33

Total Cost (for system) per Mile 0.00 0.00

 

General Air System Repairs (ATA VMRS 10) 

Parts Cost 1,114.34 191.67

Labor Hours 96.4 27.0

Average Labor Cost 4,820.00 1,350.00

Total Cost (for system) 5,934.34 1,541.67

Total Cost (for system) per Bus 1,186.87 513.89

Total Cost (for system) per Mile 0.02 0.04

 

 64
Breakdown of Maintenance Costs by Vehicle System (continued)

 Diesel Buses Fuel Cell Buses 

Brake System Repairs (ATA VMRS 13)

Parts Cost 668.69 0.00

Labor Hours 129.1 50.5

Average Labor Cost 6,455.00 2,525.00

Total Cost (for system) 7,123.69 2,525.00

Total Cost (for system) per Bus 1,424.74 841.67

Total Cost (for system) per Mile 0.02 0.06

Transmission Repairs (ATA VMRS 27) 

Parts Cost 2,878.87 90.44

Labor Hours 120.6 26.0

Average Labor Cost 6,028.00 1,300.00

Total Cost (for system) 8,906.87 1,390.44

Total Cost (for system) per Bus 1,781.37 463.48

Total Cost (for system) per Mile 0.02 0.03

 

Inspections Only – No Parts Replacements (101) 

Parts Cost 0.00 0.00

Labor Hours 639.6 493.4

Average Labor Cost 31,980.00 24,670.00

Total Cost (for system) 31,980.00 24,670.00

Total Cost (for system) per Bus 6,396.00 8,223.33

Total Cost (for system) per Mile 0.09 0.61

 

Cab, Body, and Accessories Systems Repairs 

(ATA VMRS 02-Cab and Sheet Metal, 50-Accessories, 71-Body) 

Parts Cost 15,485.05 1,001.63

Labor Hours 625.3 232.9

Average Labor Cost 31,265.5 11,645.00

Total Cost (for system) 46,750.55 12,646.63

Total Cost (for system) per Bus 9,350.11 4,215.54

Total Cost (for system) per Mile 0.13 0.31

 

HVAC System Repairs (ATA VMRS 01) 

Parts Cost 1,696.43 153.64

Labor Hours 85.8 77.8

Average Labor Cost 4,290.00 3,890.00

Total Cost (for system) 5,986.43 4,043.64

Total Cost (for system) per Bus 1,197.29 1,347.88

Total Cost (for system) per Mile 0.02 0.10

 

 65
Breakdown of Maintenance Costs by Vehicle System (continued)

 Diesel Buses Fuel Cell Buses 

Lighting System Repairs (ATA VMRS 34)

Parts Cost 3,479.95 56.08

Labor Hours 76.1 9.2

Average Labor Cost 3,802.50 460.00

Total Cost (for system) 7,282.45 516.08

Total Cost (for system) per Bus 1,456.49 172.03

Total Cost (for system) per Mile 0.02 0.01

 

Frame, Steering, and Suspension Repairs (ATA VMRS 14-Frame, 15-Steering, 16-Suspension) 

Parts Cost 9,472.75 0.00

Labor Hours 174.1 18.5

Average Labor Cost 8,702.50 925.00

Total Cost (for system) 18,175.25 925.00

Total Cost (for system) per Bus 3,635.05 308.33

Total Cost (for system) per Mile 0.05 0.02

 

Axle, Wheel, and Drive Shaft Repairs (ATA VMRS 11-Front Axle, 18-Wheels, 22-Rear Axle, 24-

Drive Shaft) 

Parts Cost 146.40 11.88

Labor Hours 33.0 7.5

Average Labor Cost 1,647.50 375.00

Total Cost (for system) 1,793.90 386.88

Total Cost (for system) per Bus 358.78 128.96

Total Cost (for system) per Mile 0.00 0.01

 

Tire Repairs (ATA VMRS 17)

Parts Cost 0.00 0.00

Labor Hours 0.0 5.8

Average Labor Cost 0.00 290.00

Total Cost (for system) 0.00 290.00

Total Cost (for system) per Bus 0.00 96.67

Total Cost (for system) per Mile 0.00 0.01

 66
Notes

1. To compare the hydrogen fuel dispensed and fuel economy to diesel, the hydrogen dispensed 

was also converted into diesel energy equivalent gallons. The general energy conversions are as 

follows, actual energy content will vary by location: 

Lower heating value (LHV) for hydrogen = 51,532 Btu/lb 

LHV for diesel = 128,400 Btu/lb 

1 kg = 2.205 * lb 

51,532 Btu/lb * 2.205 lb/kg = 113,628 Btu/kg 

Diesel/hydrogen = 128,400 Btu/gallon / 113,628 Btu/kg = 1.13 kg/diesel gallon 

2. The propulsion-related systems were chosen to include only those systems of the vehicles that 

could be directly impacted by the selection of a fuel/advanced technology. 

3. ATA VMRS coding is based on parts that were replaced. If there was no part replaced in a given 

repair, then the code was chosen by the system being worked on. 

4. In general, inspections (with no part replacements) were only included in the overall totals (not by 

system). 101 was created to track labor costs for PM inspections. 

5. ATA VMRS 02-Cab and Sheet Metal represents seats, doors, etc.; ATA VMRS 50-Accessories 

represents things like fire extinguishers, test kits, etc.; ATA VMRS 71-Body represent mostly 

windows and windshields. 

6. Average labor cost is assumed to be $50 per hour. 

7. Warranty costs are not included. 

 67
Appendix: Fleet Summary Statistics – SI Units 

Fleet Summary Statistics: Santa Clara Valley Transportation Authority (VTA)

Diesel and FCB Study Groups 

Fleet Operations and Economics

Diesel Buses Fuel Cell Buses 

Number of Vehicles 5 3

Period Used for Fuel and Oil Op Analysis 3/05-7/06 3/05-7/06

Total Number of Months in Period 17 17

Fuel and Oil Analysis Base Fleet Kilometers 580,067 64,707

Period Used for Maintenance Op Analysis 3/05-7/06 3/05-7/06

Total Number of Months in Period 17 17

Maintenance Analysis Base Fleet Kilometers 593,017 65,062

Average Monthly Kilometers per Vehicle 6,977 1,302

Availability 85% 58%

Fleet Fuel Usage in Diesel L/H2 kg 342,554 12,904

Roadcalls 45 45

RCs Kilometers Between Roadcalls (kMBRC) 13,178 1,446

Propulsion Roadcalls 34 44

Propulsion kMBRC 17,442 1,479

 

Fleet kg Hydrogen/100 km 19.94

Representative Fleet MPG (L/100 km) 59.05 66.80

 

Hydrogen Cost per kg 9.06

Diesel Cost per Liter 0.55 

Fuel Cost per Kilometer 0.32 1.81

 

Total Scheduled Repair Cost per Kilometer 0.08 0.43

Total Unscheduled Repair Cost per Kilometer 0.26 1.77

Total Maintenance Cost per Kilometer 0.34 2.21

 

Total Operating Cost per Kilometer 0.66 4.01

Maintenance Costs

 Diesel Buses Fuel Cell Buses 

Fleet Mileage 593,017 65,062

 

Total Parts Cost 58,602.26 1,658.18

Total Labor Hours 2829.1 2837.4

Average Labor Cost (@ $50.00 per hour) 141,455.00 141,870.00

 

Total Maintenance Cost 200,057.26 143,528.18

Total Maintenance Cost per Bus 40,011.45 47,842.73

Total Maintenance Cost per Kilometer 0.34 2.21

 68
F1147-E(12/2004) 

REPORT DOCUMENTATION PAGE Form Approved 

OMB No. 0704-0188

The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, 

gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this 

collection of information, including suggestions for reducing the burden, to Department of Defense, Executive Services and Communications Directorate (0704-0188). Respondents 

should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a 

currently valid OMB control number. 

PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ORGANIZATION.

1. REPORT DATE (DD-MM-YYYY)

November 2006 

2. REPORT TYPE

Technical report 

3. DATES COVERED (From - To)

3/05 - 7/06 

5a. CONTRACT NUMBER

DE-AC36-99-GO10337 

5b. GRANT NUMBER

4. TITLE AND SUBTITLE

Santa Clara Valley Transportation Authority and San Mateo County 

Transit District -- Fuel Cell Transit Buses: Evaluation Results 

5c. PROGRAM ELEMENT NUMBER

5d. PROJECT NUMBER

NREL/TP-560-40615 

5e. TASK NUMBER

HF65.8200 

6. AUTHOR(S)

Kevin Chandler (Battelle) 

Leslie Eudy (National Renewable Energy Laboratory 

5f. WORK UNIT NUMBER

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)

National Renewable Energy Laboratory 

1617 Cole Blvd. 

Golden, CO 80401-3393 

8. PERFORMING ORGANIZATION 

REPORT NUMBER

NREL/TP-560-40615 

10. SPONSOR/MONITOR'S ACRONYM(S)

NREL 

9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES)

11. SPONSORING/MONITORING 

AGENCY REPORT NUMBER

12. DISTRIBUTION AVAILABILITY STATEMENT

National Technical Information Service 

U.S. Department of Commerce 

5285 Port Royal Road 

Springfield, VA 22161 

13. SUPPLEMENTARY NOTES

14. ABSTRACT (Maximum 200 Words)

This report provides evaluation results for prototype fuel cell transit buses operating at Santa Clara Valley 

Transportation Authority (VTA) in San Jose, California, in partnership with the San Mateo County Transit District in 

San Carlos, California. VTA has been operating three fuel cell transit buses in extra revenue service since February 

28, 2005. This report provides descriptions of the equipment used, early experiences, and evaluation results from 

the operation of the buses and the supporting hydrogen infrastructure from March 2005 through July 2006. 

15. SUBJECT TERMS

fuel cell bus; fuel cell transit bus; hydrogen infrastructure; hydrogen refueling; zero-emision bus; Santa Clara Valley 

Transportation Authority; San Mateo County Transit District 

16. SECURITY CLASSIFICATION OF: 19a. NAME OF RESPONSIBLE PERSON 

a. REPORT 

Unclassified 

b. ABSTRACT 

Unclassified

c. THIS PAGE 

Unclassified

17. LIMITATION 

OF ABSTRACT

UL 

18. NUMBER 

OF PAGES 

19b. TELEPHONE NUMBER (Include area code)

Standard Form 298 (Rev. 8/98) 

Prescribed by ANSI Std. Z39.18