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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: 

Preliminary Evaluation Results 

K. Chandler 

Battelle 

L. Eudy 

National Renewable Energy Laboratory

Technical Report 

NREL/TP-540-39365 

March 2006 
Santa Clara Valley Transportation 

Authority and San Mateo County 

Transit District 

Fuel Cell Transit Buses: 

Preliminary Evaluation Results 

K. Chandler 

Battelle 

L. Eudy 

National Renewable Energy Laboratory

Prepared under Task No. HF65.8200 

Technical Report 

NREL/TP-540-39365 

March 2006 

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by Midwest Research Institute • Battelle 

Contract No. DE-AC36-99-GO10337
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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 wish to thank each of 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 #3241 

Charles Brown #9648 

John Blase #3521 

Kendall Whitson 

San Mateo County Transit District 

David Olmeda 

Ken Quijano 

Ballard Power Systems, Inc. 

Byron Somerville 

Bill Taylor 

Gillig Corporation 

Chuck Koske 

Air Products and Chemicals, Inc. 

Mark Pedersen 

iii
Table of Contents 

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

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

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

Preliminary Evaluation Results................................................................................................... 4 

What’s Next? .............................................................................................................................. 7 

Overview......................................................................................................................................... 8 

Project Design and Data Collection............................................................................................ 9 

What are Fuel Cells and Why Use them in Transit Buses? ...................................................... 10 

Zero Emissions Buses in California.......................................................................................... 11 

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

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

Infrastructure and Facilities.......................................................................................................... 16 

Compressed Hydrogen Dispensing Station .............................................................................. 16 

Hydrogen Bus Maintenance Facility ........................................................................................ 22 

Fuel Cell and Diesel Bus Descriptions......................................................................................... 24 

VTA Fuel Cell Bus Operation .................................................................................................. 25 

Early Experience with VTA’s Fuel Cell Buses........................................................................ 25 

Training and Public Awareness.................................................................................................... 28 

Ballard Fuel Cell Development and Testing................................................................................. 30 

Evaluation Results ........................................................................................................................ 33 

Route Descriptions.................................................................................................................... 33 

Bus Use and Availability .......................................................................................................... 34 

Fuel Economy and Cost............................................................................................................ 36 

Maintenance Analysis............................................................................................................... 37 

Roadcall Analysis..................................................................................................................... 41 

What’s Next? ................................................................................................................................ 42 

Contacts......................................................................................................................................... 43 

Acronyms and Abbreviations ....................................................................................................... 45 

References and Related Reports ................................................................................................... 46 

Appendix: Fleet Summary Statistics............................................................................................. 49 

iv
Executive Summary 

This report provides preliminary 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 provides descriptions of the equipment 

used (buses and infrastructure), early experience and lessons learned, and preliminary evaluation 

results from the operation of the buses and supporting hydrogen fuel station from March 2005 

through October 2005 (eight 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 and 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. 

The fuel cell buses at VTA are considered prototype technology, and 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 improvement of the vehicles, 

infrastructure, and procedures. 

Infrastructure and Facilities 

VTA has three bus operation depots: the 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, designed and constructed by Air Products and Chemicals, Inc. 

(Air Products), was completed in May 2004 (approximately $640,000 for VTA, plus liquid 

hydrogen shipments to the station); however, actual dispensing of hydrogen at the station did not 

start until November 2004. During initial use of the hydrogen fueling infrastructure, there were 

some significant challenges and problems 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 

1
of experience and precedence with this application of hydrogen in the San Jose area and due to 

some technical problems with the station. 

A few setbacks have occurred at VTA’s hydrogen dispensing station. These include an incident 

with a thermocouple failure, followed by several false alarms, which caused the local fire 

officials to temporarily stop the operation of the hydrogen fueling facility until corrections were 

made and issues were resolved. This prevented the fuel cell buses from being fueled with 

hydrogen for several months. Operation of the fuel cell buses and hydrogen fueling station has 

been under way in earnest since the end of February 2005 (the start of revenue service). VTA 

and local emergency responders have gained significant experience and are progressing with the 

demonstration. 

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. With any demonstration 

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

Significant progress and improvements have been made to the hydrogen dispensing station 

during the program, including, 

• Safe operation of the hydrogen dispensing station during the demonstration program with 

no injuries or recordable incidents. 

• More than 300 successful fuel cell bus and light-duty vehicle fills. 

• Systematic identification and correction of problems to ensure the hydrogen dispensing 

station was kept online to service the fuel cell bus fleet. 

• Incorporation of modifications into the station to address lessons learned during the 

station operation. 

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

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 problems 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 hydrogen fuel on board the buses. The total cost for these three facilities to meet the 

requirements of operating the hydrogen fuel cell buses at VTA 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, 

when Air Products put the new cryogenic compressor online, fueling time has been reduced to an 

average of 10-14 minutes. 

Hydrogen fuel cost an average of $8.56 per kg throughout the evaluation period (March 2005 

through October 2005). This high cost is an indicator of the low volume use of hydrogen as a 

fuel. Diesel fuel averaged $2.02 per gallon during the same evaluation period. 

2
Figure ES-1. Compressed Hydrogen Dispensing Station, Fuel Cell Bus, 

Bus Wash, and Maintenance Facility 

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 and delays in full operation of the dispensing station caused the 

loss of approximately 50% of the hydrogen fuel. 

Early Experience 

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

the fleet and was held at VTA. It 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 at Ballard for the fuel cell propulsion system, as well as customized 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. A quick-reference card 

was produced for emergency responders. It showed locations of specific equipment and places 

on the bus that are dangerous to be cut into. 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 the following trained personnel: two VTA mechanics, Ballard’s onsite 

mechanic, and Air Products’ staff. 

3
A major issue during this demonstration project has been the sharing of results and experiences 

with hydrogen and fuel cell technologies. This remains a challenge because of intellectual 

property sensitivities. Fuel cell propulsion applications are still in the early stages, and 

manufacturers are extremely protective of their proprietary information. In California, transit 

agencies are currently mandated to begin purchasing fuel cell buses as early as 2008. Transit 

agencies affected by these regulations need to understand all aspects of the fuel and technology 

to plan purchases and infrastructure. Fleets that are participating in the early demonstrations are 

often required to sign confidentiality agreements, making it difficult to share needed information 

with other interested fleets. 

The most serious problems encountered were related to a general lack of accurate and complete 

information regarding any specific aspect of the program. There appeared to be more marketing 

than engineering information available. This inhibits the ability to enable reasonable decisions 

for design, construction, and operation of a fuel cell bus demonstration. In many cases, 

information on fuel cell buses and infrastructure indicate that this equipment is available as 

commercial, off-the-shelf products. This just isn’t true (yet). Care will need to be taken to 

ensure that marketing does not get too far ahead of the commercialization of the fuel cell 

propulsion and supporting infrastructure equipment. 

Preliminary 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 preliminary 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; however, the fuel cell 

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

diesel buses. This caused some concerns about clearance. But 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). The fuel 

cell buses do not have a hybridized system and therefore do not have regenerative braking or 

additional energy storage. 

VTA Routes—VTA operates 54 fixed, 19 express, and 19 special/shuttle type bus 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 ZEB mechanic is 

available. 

4
Bus Use and Availability—Bus use is intended as an indicator of reliability and availability for 

bus service. The lack of bus usage may indicate downtime for maintenance or purposeful 

reduction of planned work for the buses. Figure ES-2 shows mileage and fuel cell module 

operating hour accumulation from the start of hydrogen fueling in November 2004 through 

October 2005. As to be 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, planned work for the buses as extra service, maintenance issues, and 

availability of drivers and mechanics for the fuel cell bus operation. 

During the eight-month evaluation period, the three buses accumulated 16,708 miles and 1,376 

hours on the six fuel cell modules (two per bus). Average monthly mileage per fuel cell bus was 

726 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 4,284 miles. 

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 not available for service due to any maintenance issues. 

During the evaluation period, the diesel buses had an availability rate of 84%. VTA’s goal is 

80% for diesel buses. 

During the evaluation period, the fuel cell buses had an availability rate of 52% for each 

weekday, with a goal of 67% of the time. (For this preliminary report, no differentiation was 

made between standard bus maintenance issues and those attributed specifically to the fuel cell 

and system.) 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 

78% of the time. 

0

5,000

10,000

15,000

20,000

25,000

Nov-04

Dec-04

Jan-05

Feb-05

Mar-05

Apr-05

May-05

Jun-05

Jul-05

Aug-05

Sep-05

Oct-05

Miles

0

200

400

600

800

1000

1200

1400

1600

1800

FC Hours

Cumulative Mileage

Cumulative Fuel Cell Hours

Figure ES-2. Cumulative Mileage and Fuel Cell Hours for Three Fuel Cell Buses 

5
Fuel Economy—During the evaluation period, the fuel cell buses averaged 3.05 miles per kg of 

hydrogen, which translates into 3.45 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 3.95 mpg. With the diesel buses as the baseline, the fuel cell buses had a fuel 

economy 13% 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

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 October 2005) of the two study groups of buses. All work orders for the 

study buses were collected and analyzed for this evaluation. The labor rate for maintenance was 

calculated at a constant $50 per hour, and this is not reflective of an average rate at VTA. 

Total maintenance costs were $4.26 per mile for the fuel cell buses and $0.59 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 

stage for transit bus service, which has caused a need for significant mechanic/technician labor 

for troubleshooting. 

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

cell buses had nearly $70,000 in warranty parts replaced during the evaluation period; however, 

not all of the warranty costs have been accounted for. An action item for the final report is to 

collect more complete information on warranty parts replacements and labor cost. 

6
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 ($3.06 per mile) had significantly higher propulsion-related maintenance costs than the 

diesel buses ($0.21 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 983 miles between roadcalls (MBRC) for all roadcalls and 1,044 MBRC for 

propulsion-related roadcalls. The diesel buses had 9,019 MBRC for all roadcalls and 11,424 

MBRC for propulsion-related roadcalls. 

What’s Next? 

This preliminary data report includes an eight-month evaluation period (March 2005 through 

October 2005) of the prototype fuel cell buses in demonstration at VTA. A final report is 

planned for this evaluation after at least 12 months of fuel cell bus operation at VTA. This is 

expected to be published in mid 2006. 

VTA currently plans to operate the fuel cell buses through July 2006—the end of the two-year 

demonstration and the warranty/support period for the fuel cell buses, as defined by Ballard. It is 

not clear whether this demonstration will continue beyond the end date because there are no 

grants or funds set aside to extend it. As described in this preliminary report, to continue 

operation beyond the current end point would require significant funding. VTA, Ballard, and 

Air Products have expressed interest in continuing this testing program if funding becomes 

available. Significant investment and effort have been committed to test and operate this 

equipment. There is still significant work to be done (and lessons to be learned) before fuel cell 

buses and infrastructure equipment is truly commercial. 

7
Overview 

This report provides preliminary 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 preliminary results 

from the operation of the buses and supporting hydrogen fuel station. 

This evaluation is a part of the U.S. Department of Energy’s (DOE) 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, heavy-duty 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 

support an industry commercialization decision by 2015. 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 preliminary data report examines early 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 October 2005—eight 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. 

8
The next report for this evaluation will be completed after at least 12 months of operation data 

have been analyzed for the fuel cell and diesel baseline buses. 

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 

U.S. Air Force/Hickam Air Force Base 

(Honolulu, Hawaii) 

Shuttle bus: Hydrogenics and Enova, 

battery-dominant fuel cell hybrid (one 

bus); delivery van: Hydrogenics and 

Enova, fuel cell hybrid (one van) 

Shuttle bus in operation, data 

collection started; van just going 

into service 

VTA (San Jose, California) and 

SamTrans (San Carlos, California) 

Gillig/Ballard fuel cell transit bus 

(three buses) 

Evaluation in process, interim 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, buses just 

going into service 

SunLine Transit Agency 

(Thousand Palms, California) 

New Flyer ISE Corp. hydrogen 

internal combustion engine transit 

bus (one bus), Van Hool/UTC fuel 

cell hybrid transit bus integrated by 

ISE Corp. (one bus) 

Bus in service, data collection 

started; evaluation in process, bus 

just going into service 

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 collections 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 is being collected 

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

diesel baseline data is being 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. 

9
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 

• Hydrogen fuel consumption by vehicle 

• 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 have 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 the 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: 

10
• 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 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 fuel cell transit bus demonstrations in the United States, Canada, 

and Europe. 

Zero Emissions Buses in California 

In February 2000, the California Air Resources Board (CARB) announced regulations to 

significantly reduce emissions of existing and new transit buses in California through 2015. 

CARB is a department of the California Environmental Protection Agency and oversees all air 

pollution control efforts in the state. This legislative change for emissions reductions in transit 

buses created a schedule for transit agencies to choose an alternative fuel or diesel path. The 

program provided an incentive for transit agencies to adopt low-emissions alternative fuels 

sooner rather than later. On the other hand, a transit agency could choose the diesel path, which 

required an emission reduction schedule more accelerated than that of alternative fuels. 

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). The alternative fuel path allows transit agencies to extend the 

transition period for the operation of zero-emissions technologies. 

 

2

 Information excerpted from an FTA presentation by Shang Hsiung at the American Public Transportation 

Association Bus and Paratransit Conference committee meetings in Milwaukee, Wisconsin, May 2003. 

11
Table 2. Fuel Cell Transit Bus Demonstrations – 12 Year History 

Timeframe Description 

1994-1995 FTA/Georgetown: three 30-foot fuel cell buses operating on methanol using 100 kW phosphoric acid 

fuel cell (PAFC) stacks from Fuji 

1998 FTA/Georgetown: 40-ft fuel cell bus operating on methanol using 100 kW PAFC from UTC Fuel 

Cells 

1998-2000 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 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 FTA/Georgetown: 40-foot fuel cell bus operating on methanol using 100 kW PEM fuel cell stack 

from Ballard. 

2002-2003 ThunderPower 30-foot fuel cell bus operating on compressed hydrogen using 60 kW PEM fuel cell 

stack from UTC Fuel Cells at SunLine and AC Transit 

2003-2005 Demonstration project in Europe, Iceland, and Australia including 33 fuel cell buses using Ballard 

PEM fuel cell stacks and compressed hydrogen in 40-foot buses. (CUTE, ECTOS, & STEP) 

2004-2006 Demonstration project in the United States: three fuel cell buses using Ballard fuel cell stacks and 

compressed hydrogen in 40-foot buses at VTA, three fuel cell buses using UTC fuel cell stacks and 

compressed hydrogen in 40-foot buses at AC Transit, one fuel cell bus using UTC fuel cell stack 

and compressed hydrogen in a 40-foot bus at SunLine Transit Agency 

2004-2006 Demonstration project in China: three fuel cell buses using Ballard PEM fuel cell stacks and 

compressed hydrogen in 40-foot buses. 

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 choose the 

alternative-fuel path are not required to purchase ZEBs at the 15% of new bus 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. 

Since 2000, these regulations have changed. The most recent change was released in October 

2005 in regards to the Zero-Emissions Bus Demonstration Project, which adjusted the required 

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

demonstration projects 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 new legislation. 

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 the 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 exceeds $295 million (in fiscal year 

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

peak demand) and 100 light rail vehicles. Annual ridership exceeds 37 million (in fiscal year 

12
2005) in a service area that covers approximately 326 square miles (see Figure 2). The 

organization adopted a Clean Fuels Strategy in December of 2000, which 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 (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 and in the 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. 

13
• Provide community outreach and educate the public on fuel cell and hydrogen 

technologies. 

Table 3. General Equipment for the Fuel Cell Bus Demonstration Equipment 

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

FTA provided guidance in the evaluation strategy. 

• DOE provided funding directly 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 

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 

14
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. 

• 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. 

• 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 and supplies the hydrogen fuel used in this project 

at VTA. Air Products also owns the VTA station and is responsible for its maintenance. 

• The 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 contract to Air Products to design and build the hydrogen 

fueling facility at VTA’s Cerone Operations Division. Construction began in September 2003, 

and the station was completed by May 2004. 

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

buses and a special two-bay maintenance facility that could accommodate hydrogen use inside 

the building. 

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. 

15
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 220 buses operating seven days a week. 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 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 to design and build the fueling facility. 

Construction began in September 2003, and the station was completed in May 2004; however, 

actual dispensing of hydrogen at the station did not start until November 2004. VTA has a 

capital lease for the facility (shown in Figure 3), which is owned and maintained by Air 

Products. VTA provided the concrete pad for the station at the Cerone depot. VTA paid 

approximately $480,000 up front and has monthly payments for three years (about $4,400 per 

month) with a grand total of approximately $640,000 for the station plus the cost of liquid 

hydrogen. 

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 

three-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 certain level, the compressor is 

activated, the tanks are refilled, and the bus fueling process is completed. 

Figure 3. Compressed Hydrogen Dispensing Station 

at VTA's Cerone Operations Division 

16
The hydrogen dispenser (Figure 4) is equipped for a communications fill. The communications 

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

to 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 4. Hydrogen Dispenser 

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

station to continue operation when the primary compressor undergoes scheduled maintenance or 

experiences a failure. As a newer Air Products design, the primary compressor can provide a 

fast fill in about eight minutes. The secondary compressor is a reliable, proven design that 

provides a bus fill in less than 20 minutes. 

To ensure high reliability and safety, the station includes numerous shut down and alarming 

devices to alert the fleet and Air Products of any potential problems. These devices include 

flame sensors, alarms, and emergency stop (E-stop) buttons (Figure 5) that are monitored onsite 

by VTA and remotely by Air Products. When activated, the E-stop buttons shut down the 

system and close the liquid tank valves. 

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

ensure safety, no other VTA employees are authorized to dispense hydrogen from the station. 

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

dispensing equipment. 

 

17
Figure 5. Flame Sensors (left and top) and Emergency Shut-off (right) 

at the Hydrogen Dispensing Facility 

Early Experience with Hydrogen Dispensing—Operating and maintaining the requisite 

hydrogen fueling infrastructure for the fuel cell bus demonstration had been 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 

compressor failed, causing a liquid hydrogen leak and fire. This thermocouple monitors the 

discharge temperature and is used to control the compressor. The system was going through 

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

seconds. 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 

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

batch were replaced, including units installed at two other facilities. Although there was no 

major damage resulting from the fire, the station had to be 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, have also caused delays 

to VTA’s station operation. The majority of the alarms could be traced to one of the following 

causes. 

18
• Power Loss: In the case of a power loss, safety systems at the VTA facilities will trigger 

an alarm. On two occasions, false alarms were determined to be caused by temporary 

power losses at the fueling station. 

• 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 in the area, could have 

caused the false alarms. This experience resulted in the development and installation of 

improved flame detectors as well as the implementation of new procedures if such 

activities take place. 

• 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 

which greatly improved the reliability and reduced the number of false alarms, was installed.

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. This was 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 that needed correction. The local E-stop, or 

remote shut down using the electrical breaker, was never activated by personnel onsite, which 

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

department. 

The second incident was a small leak and vapor cloud at the fueling facility. The leak occurred 

at the primary 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 secondary cryogenic compressor. Repairs were made to fix the 

leak and the primary cryogenic compressor was returned back into service. 

The third incident occurred during a bus fueling at the station. The primary 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 primary compressor kept running even though 

the cascade tanks were not filling and venting continued. When the primary compressor shut 

down, the secondary system came online as back up. VTA personnel then noticed a small leak 

19
and vapor cloud at the secondary compressor. VTA personnel shut down the entire system using 

the E-stop button. An Air Products technician corrected the secondary compressor leak to get 

the system back online. The primary compressor needed more extensive repairs, necessitating 

the continued use of the back up. 

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

caused delays and 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. 

Modifications to equipment, software, and procedures seem to be working; there have been no 

incidents at the station since July 2004. 

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. Significant progress and improvements have been made to the hydrogen dispensing 

station during the program, including: 

• The safe operation the hydrogen dispensing station during the demonstration program 

with no injuries or recordable incidents. 

• More than 300 successful fuel cell bus and light-duty vehicle fills. 

• The systematic identification and correction of problems to ensure the hydrogen 

dispensing station was kept online to service the fuel cell bus fleet. 

• Incorporating modifications into the station to address lessons learned during the station 

operation. 

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

2004; (however, fueling of the buses did not start until November 2004) for testing of the bus 

fuel and propulsion systems. Through early November 2005, the fueling station has 22,045 kg of 

hydrogen delivered. The station has insufficient fueling use, causing much of the fuel to be lost 

to boil-off. With the buses operating since February 2005, vent and boil-off losses have been at 

approximately 50%. This implies that the other 50% of the hydrogen has been lost to boil-off 

from the station. As the bus use increased, the use of the hydrogen has improved. 

Figure 6 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 the newer (primary) compressor came online in April 2005, the fueling times improved 

considerably, with fill times averaging between 10 and 14 minutes. 

20
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

Average kg per Fueling Average Fueling Time (min)

Figure 6. Average Hydrogen Fueling Amounts and Average Fueling Time 

Figure 7 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. This cost would equate to 

approximately $11.77 per diesel equivalent gallon. Based on the loss of hydrogen due to venting 

and boil-off losses as described above, the cost of hydrogen fuel might be considered to be 

double. The average hydrogen cost per kg used for the evaluation, discussed later in this report, 

is $8.56 for the data period of March 2005 through October 2005. 

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 8. 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 (like with the rest of the country). 

The average diesel fuel cost per gallon for the evaluation period was $2.02. 

21
$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

Figure 7. Average Price Paid ($/kg) for Liquid Hydrogen Delivered to VTA Station 

Hydrogen Bus Maintenance Facility 

A separate maintenance facility was also 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 in accordance with the fire marshal requirements. This two-bay 

facility, shown in Figure 9, 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 on hydrogen vehicles. These 

include hydrogen and flame sensors and an anti-static coating on the doors. When sensors detect 

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. 

Evacuation is required at 50% (2% hydrogen in air) LFL. 

The new bus wash (shown in Figure 10) 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 total cost for adding these three facilities to meet the requirements 

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

22
$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

Overall Average Diesel Cost 

Figure 8. Average Diesel Fuel Cost ($/gallon) at VTA (March 2005 through October 2005) 

Figure 9. Maintenance Facility Used for the Fuel Cell Buses at VTA 

Figure 10. Bus Wash (left) and Maintenance Facility (right) 

23
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 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)—a price that includes system integration engineering, a two-year warranty, parts, training, 

and support from Gillig and Ballard. 

Table 4 shows a summary of vehicle system descriptions for the fuel cell and diesel baseline 

study groups of buses. Both bus groups are Gillig low-floor 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 about clearance. But 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 standard transmission and retarder. The fuel cell buses do not have a hybridized 

system, and therefore, do not have regenerative braking or additional energy storage. Table 5 

provides several additional details on the fuel cell propulsion system, including the electric motor 

and hydrogen fuel storage details. 

Table 4. Fuel Cell and Diesel Bus System Descriptions 

Cerone Depot Vehicle System Fuel Cell Buses Diesel Buses 

Number of Buses Three Five 

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 

24
Table 5. Additional Fuel Cell Propulsion System Descriptions 

Propulsion Systems Fuel Cell Buses 

Manufacturer/Integrator Gillig/Ballard 

Drive System Fuel cell powerplant, 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 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 has had a mechanic onsite at VTA 

since the buses were delivered. VTA’s procedure for operating the fuel cell buses includes a pretrip by a VTA mechanic while the fuel cell systems are “warming up.” 

The fuel cell modules use hydrogen and oxygen to produce electricity, heat, and water. The 

electricity produced powers the bus through an electric motor directly connected to the drive 

axle. The fuel cell bus system enters a start-up 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/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. 

While this “warm up” process is occurring, the drivers perform their pre-trip safety inspections 

of the bus before starting a route. 

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.). 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. 

The system is now in safe shut-down mode. 

Early Experience with VTA’s Fuel Cell Buses 

Because fuel cell bus technology is new to the 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. VTA operated the buses in test mode as much as possible to 

25
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 maintenance workers and other VTA staff and conducted 

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 mounted on the roof of fuel cell buses 

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

through VTA’s existing bus wash. The 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 if a collision occurs. The fleet 

had to inspect 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 a typical 40-foot bus, the fleet has 

to limit the number of standing passengers to meet weight requirements. This could be 

an issue when operating on some of the 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 are not always easy to obtain. 

Waiting for these replacement parts can potentially increase downtime for the fuel cell 

buses. Ballard carefully monitors 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 have been working together to try 

to minimize this potential downtime. 

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 a 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. 

26
• “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.” 

27
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 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 at Ballard for the fuel cell 

propulsion system, as well as customized 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 emergency response card 

was produced for emergency responders showing location of specific equipment and places 

where it would be dangerous for the bus to be cut into. 

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

allow. Events attended, tours of, and presentations about the fuel cell buses at VTA 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 to the Santa Clara County Fuel Cell 

Working Group at its 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-June 2, 2005: VTA participated in the United Nations World Environment Day 

in San Francisco by displaying the ZEB and providing related information. International 

VIP’s, environmental experts, and media representatives rode the ZEB on pre-scheduled 

routes. 

28
• 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. 

• 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 also 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 event 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, CA. The ZEB was on display and program materials were provided to 

workshop 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. Tour attendees received materials and 

a presentation by VTA staff on the ZEB program. 

• 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," 

who visited VTA's Cerone facility to learn about the ZEBs. 

29
Ballard Fuel Cell Development and Testing 

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

Columbia, Canada, and was founded in 1979 as a research company investigating high-energy 

lithium batteries. Ballard started work on PEM fuel cells in 1983 and began demonstration of 

this fuel cell technology in transit buses in 1991 (shown in Table 6). 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 is focused on 

reducing cost, increasing durability, improving freeze start, and increasing power density. 

Table 6. 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 bus could hold 60 passengers, used 20 fuel cell 

stacks, 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 

30
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 bus could hold 60 passengers, 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, and 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 to 

date. DaimlerChrysler and Ballard embarked on an 11-city fuel cell 

bus implementation and demonstration program, which included 33 

Mercedes-Benz Citaro buses. The timeframe for this phase is 2002-

present and is now planned to operate through 2006. Some significant 

results are expected to be reported in early 2006. 

31
Each of the following 11 cities have received and have been operating three fuel cell buses each: 

• 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 

o Reykjavik, Iceland 

• Sustainable Transport Energy for Perth 

o Perth, Australia 

The original two-year demonstration for these 11 cities is essentially over now; however, an 

extension of one year of operation has been approved. So far, seven of the original 11 cities have 

agreed to participate in this additional year of operation. The general objectives for this extra 

year are to get more operating experience and possibly take the fuel cell propulsion system to 

failure. This additional operation is a part of a program called HyFLEET:CUTE. The fuel cell 

buses from two cities not participating in the additional operation are planned to be transferred to 

Hamburg for operation. Hamburg will have a total of nine buses in operation for this 

demonstration. Additional information on these demonstration sites is provided at 

www.fuel-cell-bus-club.com. 

On November 23, 2005, Ballard Power Systems announced that three more Citaro fuel cell buses 

from Mercedes-Benz were placed into service in Beijing, China. This project was co-funded by 

the United Nations Development Program/Global Environment Facility. 

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 is significantly different 

than the Mercedes-Benz Citaro buses used for the other Phase 5 sites. 

32
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 revenue service from the Cerone Operating Division. 

This report provides analysis and discussion focused on a data period including March 2005 

through October 2005, an eight-month evaluation period. Some results and discussion presented 

in this report will 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 is focused on documenting progress 

and opportunities for improvement of the vehicles, infrastructure, and procedures. 

Route Descriptions 

VTA operates 54 fixed, 19 express, and 19 special/shuttle type bus 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 7. All 

standard buses at Cerone are randomly dispatched on routes. 

Table 7. Summary of Total Weekly Bus Usage from Cerone 

Day of Week Total Miles Hours Avg. Speed 

Weekday 22,061.2 1,527.22 14.4 

Saturday 11,294.2 776.13 14.6 

Sunday 9,600.6 666.55 14.4 

Weekly Total 131,200.8 9,078.78 14.5 

 

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. This is meant to prevent a situation where passengers are stranded for a long 

period in the event of a failure of the fuel cell bus. The 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 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, which have 

changed over time to accommodate having the fuel cell buses operate on several VTA routes and 

experience different operating types. 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 blocks and assignments are shown in 

Table 8. The fuel cell buses have generally been used at an average speed slightly less than the 

fleet average for the diesel buses at Cerone. 

33
Table 8. Route Block Assignments for the Fuel Cell Buses 

Block Routes Effective 

Date 

Pull Out 

Time 

Pull In 

Time 

Total 

Time 

Total 

Miles 

Average 

Speed 

45 2/28/2005 8:03 a.m. 2:00 p.m. 5:57 52.0 8.7

33 5/2/2005 8:00 a.m. 2:30 p.m. 6:30 86.5 13.3

47 7/5/2005 8:00 a.m. 2:14 p.m. 6:14 71.5 11.5

9781 

102/22/71 9/6/2005 6:42 a.m. 2:27 p.m. 7:45 114.7 14.8

47 2/28/2005 8:22 a.m. 2:00 p.m. 5:38 71.5 12.6

46 5/2/2005 8:00 a.m. 2:23 p.m. 6:23 84.0 13.2

32 5/31/2005 8:00 a.m. 2:21 p.m. 6:21 85.5 13.5

53 7/5/2005 8:00 a.m. 2:22 p.m. 6:22 61.0 9.6

9782 

62 9/6/2005 6:42 a.m. 2:23 p.m. 7:41 88.0 11.5

Bus Use and Availability 

Bus use is intended as an indicator of reliability and availability for bus service. 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 11 shows mileage and fuel cell module operating hour accumulation from the start of 

hydrogen fueling in November 2004 through October 2005. 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 by using the buses only on weekdays, planned work for the 

buses as extra service, maintenance issues, and availability of drivers and mechanics for the fuel 

cell bus operation. 

Table 9 summarizes average monthly mileage accumulation by bus and study group for the 

evaluation period. The three fuel cell buses accumulated 16,708 miles in the eight-month 

evaluation period and 1,376 hours on the fuel cell modules. Average monthly mileage per fuel 

cell bus was 726 miles. 

The diesel study buses were operated in normal VTA service from Cerone, including weekend 

operation. The average monthly mileage per bus from the evaluation period was 4,284 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 

essentially the same as that experienced during the evaluation period. 

34
0

5,000

10,000

15,000

20,000

25,000

Nov-04

Dec-04

Jan-05

Feb-05

Mar-05

Apr-05

May-05

Jun-05

Jul-05

Aug-05

Sep-05

Oct-05

Miles

0

200

400

600

800

1000

1200

1400

1600

1800

FC Hours

Cumulative Mileage

Cumulative Fuel Cell Hours

Figure 11. Cumulative Mileage and Fuel Cell Hours for Three Fuel Cell Buses 

Table 9. Average Monthly Mileage (Evaluation Period) 

Bus Starting 

Hubodometer 

Ending 

Hubodometer 

Total 

Mileage Months

Monthly 

Average 

Mileage 

Fuel Cell 

Module 

Hours 

4001 7,930 14,428 6,498 8 812 561 

4002 959 5,781 4,822 7 689 402 

4003 954 6,342 5,388 8 674 413 

Fuel Cell 16,708 23 726 1,376 

2229 134,738 161,852 30,408 8 3,801 N/A 

2230 115,857 152,772 36,915 8 4,614 N/A 

2231 130,452 164,663 36,434 8 4,554 N/A 

2232 122,086 156,950 34,864 8 4,358 N/A 

2233 134,142 166,880 32,738 8 4,092 N/A 

Diesel 171,359 40 4,284 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 not available for service due to any maintenance issues. 

During the evaluation period, the diesel buses had an availability rate of 84%. VTA’s goal is 

80% for diesel buses. 

During the evaluation period, the fuel cell buses had an availability rate of 52% for each 

weekday, with a goal of 67% of the time. (For this preliminary report, no differentiation was 

made between standard bus maintenance issues and those attributed specifically to the fuel cell 

and system.) 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 

78% of the time. 

35
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 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 is shown in the Appendix. 

Table 10 shows hydrogen and diesel fuel consumption and fuel economy for the two study 

groups during the evaluation period. The fuel cell buses averaged 3.05 miles per kg of hydrogen, 

which translates into 3.45 miles per diesel equivalent gallons (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 3.95 mpg. With 

diesel as the baseline, the fuel cell buses had a fuel economy that was 13% lower on an energy 

equivalent basis. Figure 12 shows average monthly energy equivalent fuel economies 

throughout the evaluation period for the fuel cell and diesel buses. 

Table 10. Fuel Use and Economy (Evaluation Period) 

Bus Mileage 

(Fuel Base) 

Hydrogen 

(kg) 

Miles per 

kg 

Diesel Equivalent 

Amount (Gallon) 

Miles per 

Gallon 

4001 6,498 2,188.8 2.97 1,937.0 3.35 

4002 4,822 1,584.4 3.04 1,402.1 3.44 

4003 5,388 1,696.1 3.18 1,501.0 3.59 

Fuel Cell 16,708 5,469.3 3.05 4,840.1 3.45 

2229 25,996 6,412.4 4.05 

2230 36,915 9,741.4 3.79 

2231 33,106 8,507.1 3.89 

2232 34,864 8,940.0 3.90 

2233 32,738 7,873.2 4.16 

Diesel 163,619 41,474.1 3.95 

As reported earlier, the average cost of hydrogen during the evaluation period was $8.56 per kg 

of hydrogen and the average cost of diesel fuel during the evaluation period was $2.02 per 

gallon. These average fuel costs translate into a fuel cost per mile of $2.80 for the fuel cell buses 

and $0.51 per mile for the diesel buses. If hydrogen fuel losses at the station were taken into 

account, the fuel cost per mile for the fuel cell buses would be essentially double. 

36
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

Miles per Gallon (Diesel Equivalent)

Fuel Cell Bus Diesel Bus

Figure 12. Average Fuel Economy (mpg) by Month 

Maintenance Analysis 

The maintenance cost analysis in this section is for only the evaluation period (March 2005 

through October 2005) for the two study groups of buses. Warranty costs are shown but not 

included in the cost-per-mile calculations. 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, and 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 11 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. The overall average maintenance cost per mile for the fuel 

cell buses was $4.26. 

37
Table 11. Total Maintenance Costs (Evaluation Period) 

Bus Mileage Warranty 

Parts ($) Parts ($) Labor Hours 

Cost per 

Mile ($) 

4001 6,498 5,350.25 520.52 347.8 2.76 

4002 4,822 31,395.50 1,528.56 496.4 5.46 

4003 5,388 32,022.64 349.91 531.4 5.00 

Total Fuel Cell 16,708 68,768.39 2,398.99 1,375.6 4.26 

Avg. per Bus 5,569 22,922.80 799.66 458.5 -- 

2229 30,408 1,238.75 7,839.45 383.0 0.89 

2230 36,915 468.81 5,697.16 271.1 0.52 

2231 36,434 1,981.25 5,075.11 234.7 0.46 

2232 34,864 2,871.45 5,246.33 276.3 0.55 

2233 32,738 440.20 6,446.44 247.5 0.58 

Total Diesel 171,359 7,000.46 30,304.49 1,412.6 0.59 

Avg. per Bus 34,272 1,400.09 6,060.90 282.5 -- 

Warranty costs listed are those that were available for the data collection and evaluation. A 

significant portion of the cost for parts covered under warranty is not yet accounted for. A 

priority for the final results report for this evaluation is to attempt to collect more of the warranty 

costs for the fuel cell buses. Some of the warranty costs that were not collected at this point 

include the preventive maintenance filter parts, which were listed as no-cost to VTA. 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. 

The diesel buses had similar maintenance costs per mile for four of the five buses and the overall 

average maintenance cost per mile for the diesel group was $0.59. Bus 2229 had a significantly 

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. 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 12 shows maintenance costs by vehicle 

system and bus study group. The vehicle systems shown in the table include the following. 

• Cab, Body, and Accessories: Includes body repairs following accidents, glass, and paint; 

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, and propulsion control; non-lighting electrical (charging, cranking, ignition); air 

intake; cooling; and transmission 

• Preventive Maintenance Inspections (PMI): Labor for inspections during preventive 

maintenance 

• Brakes 

• Frame, Steering, and Suspension 

38
• Heating, Ventilation, and Air Conditioning (HVAC) 

• Lighting 

• Air System, General 

• Axles, Wheels, and Drive Shaft 

• Tires 

The highest percent maintenance cost systems for the fuel cell buses were propulsion-related, 

PMI, and cab, body and accessories. The diesel buses had those three system maintenance 

groups as the highest cost and also frame, steering, and suspension. The additional category of 

frame, steering, and suspension reflects the higher use of the diesel buses compared to the fuel 

cell buses. 

Table 12 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 0.39 9 0.12 21 

Propulsion-Related 3.06 72 0.21 36 

PMI 0.65 15 0.09 15 

Brakes 0.07 2 0.02 3 

Frame, Steering, 

and Suspension 0.00 0 0.08 14 

HVAC 0.05 1 0.02 3 

Lighting 0.01 0 0.02 3 

Air, General 0.00 0 0.03 5 

Axles, Wheels, and 

Drive Shaft 0.01 0 0.00 0 

Tires 0.02 1 0.00 0 

Total 4.26 100 0.59 100 

Preventive maintenance for the fuel cell and diesel buses was 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 based on bus operation. These 

preventive maintenance schedules for the fuel cell buses do not necessarily overlap, and at times, 

the fuel cell buses may be in for preventive maintenance for one schedule one week and another 

the following week. Ballard has been working to harmonize these schedules. 

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 13 shows a breakdown of the propulsion-related system repairs for 

the two study groups during the evaluation period. The fuel cell buses had significantly higher 

maintenance costs for all of the systems shown in the table except for exhaust and transmission 

systems. 

39
Table 13. Propulsion-Related Maintenance Cost by System (Evaluation Period) 

Maintenance System Costs Fuel Cell Diesel 

Mileage 16,708 171,359 

Total Propulsion-related Systems (Roll-Up) 

Parts cost ($) 2,381.59 11,737.99 

Labor hours 973.6 491.6 

Total cost ($) 51,061.59 36,315.49 

Total cost ($) per mile 3.06 0.21 

Exhaust System Repairs 

Parts cost ($) 0.00 86.97 

Labor hours 0.0 100.4 

Total cost ($) 0.00 5,106.97 

Total cost ($) per mile 0.00 0.03 

Fuel System Repairs 

Parts cost ($) 1,042.00 3,226.63 

Labor hours 184.9 33.1 

Total cost ($) 10,287.00 4,879.13 

Total cost ($) per mile 0.62 0.03 

Engine System Repairs 

Parts cost ($) 299.93 3,924.18 

Labor hours 351.0 158.7 

Total cost ($) 17,849.93 11,859.18 

Total cost ($) per mile 1.07 0.07 

Electric Motor and Fuel Cell Module Repairs 

Parts cost ($) 0.00 0.00 

Labor hours 106.4 0.0 

Total cost ($) 5,320.00 0.00 

Total cost ($) per mile 0.32 0.000 

Non-Lighting Electrical System Repairs (General Electrical, 

Charging, Cranking, Ignition) 

Parts Cost ($) 0.00 463.33 

Labor Hours 70.9 25.5 

Total Cost ($) 3,545.00 1,738.33 

Total cost ($) per mile 0.21 0.01 

Air Intake System Repairs 

Parts cost ($) 509.50 312.79 

Labor hours 109.8 0.5 

Total cost ($) 5,999.50 337.79 

Total cost ($) per mile 0.36 0.00 

Cooling System Repairs 

Parts cost ($) 530.16 1,895.65 

Labor hours 141.1 84.4 

Total cost ($) 7,585.16 6,113.15 

Total cost ($) per mile 0.45 0.04 

Transmission Repairs 

Parts cost ($) 0.00 1,828.44 

Labor hours 9.5 89.1 

Total cost ($) 475.00 6,280.94 

Total cost ($) per mile 0.023 0.04 

40
Roadcall Analysis 

A roadcall (RC) or revenue vehicle system failure (as named for the National Transit Database3) 

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 includes 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 14 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. 

Table 14. Roadcalls and MBRC (Evaluation Period) 

Bus Mileage All 

Roadcalls All MBRC Propulsion Roadcalls 

Propulsion 

MBRC 

4001 6,498 6 1,083 6 1,083 

4002 4,822 6 804 5 964 

4003 5,388 5 1,078 5 1,078 

Fuel Cell 16,708 17 983 16 1,044 

2229 30,408 3 10,136 3 10,136 

2230 36,915 2 18,458 2 18,458 

2231 36,434 4 9,109 2 18,217 

2232 34,864 4 8,716 4 8,716 

2233 32,738 6 5,456 4 8,185 

Diesel 171,359 19 9,019 15 11,424 

 

3

 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. 

41
What’s Next? 

This preliminary data report includes an eight-month evaluation period (March 2005 through 

October 2005) of the prototype fuel cell buses in demonstration at VTA. A final report is 

planned for this evaluation following at least 12 months of fuel cell bus operation at VTA. This 

is expected to be published in mid-2006. 

VTA currently plans to operate the fuel cell buses through July 2006—the end of the two-year 

demonstration and the warranty/support period for the fuel cell buses, as defined by Ballard. It is 

not clear whether this demonstration will continue beyond the end date because there are no 

grants or funds set aside to extend it. As described in this preliminary data report, to continue 

operation beyond the current end point would require significant funding. VTA, Ballard, and 

Air Products have expressed interest in continuing this testing program if funding becomes 

available. Significant investment and effort have been committed to test and operate this 

equipment. There is still significant work to be done (and lessons to be learned) before fuel cell 

buses and infrastructure equipment is truly commercial. 

42
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 

43
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 

Mark Pedersen 

Commercial Development 

Phone: 707-748-7595, ext. 18 

E-mail: pedersms@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 

44
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 

E-stop Emergency stop 

FCB Fuel cell buses 

FTA Federal Transit Administration 

GVWR Gross vehicle weight rating 

HFCIT Hydrogen, Fuel Cells & Infrastructure Technologies 

HVAC Heating, ventilation, and air conditioning 

in Inches 

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 

UTC United Technologies Corporation 

VTA Santa Clara Valley Transportation Authority 

ZEB Zero emissions bus 

ZEbus Ballard zero emission bus 

45
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 9 

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

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 

46
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 

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 

47
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 

48
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 3/05-10/05 3/05-10/05

Total Number of Months in Period 8 8

Fuel and Oil Analysis Base Fleet Mileage 163,619 16,708

Period Used for Maintenance Op Analysis 3/05-10/05 3/05-10/05

Total Number of Months in Period 8 8

Maintenance Analysis Base Fleet Mileage 171,359 16,708

Average Monthly Mileage per Vehicle 4,284 696

Availability 84% 1.56/2.00

Fleet Fuel Usage in Diesel Gal/H2 kg 41,474 5,469

Roadcalls 19 17

RCs MBRC 9,019 983

Propulsion Roadcalls 15 16

Propulsion MBRC 11,424 1,044

 

Fleet Miles/Kg Hydrogen 3.05

(1.13 kg H2/gal Diesel fuel) 

Representative Fleet MPG (energy equiv) 3.95 3.45

 

Hydrogen cost per kg 8.56

Diesel Cost per gallon 2.02 

Fuel Cost per Mile 0.51 2.8

 

Total Scheduled Repair Cost per Mile 0.122 0.715

Total Unscheduled Repair cost per Mile 0.467 3.545

Total Maintenance Cost per Mile 0.59 4.26

 

Total Operating Cost per Mile 1.10 7.06

Maintenance Costs

 Diesel Buses Fuel Cell Buses 

Fleet Mileage 171,359 16,708

 

Total Parts Cost 30,304.64 2,398.99

Total Labor Hours 1412.6 1375.6

Average Labor Cost (@ $50.00 per hour) 70,627.50 68,780.00

 

Total Maintenance Cost 100,932.14 71,178.99

Total Maintenance Cost per Bus 20,186.43 23,726.33

Total Maintenance Cost per Mile 0.59 4.26

49
Breakdown of Maintenance Costs by Vehicle System

Diesel Buses Fuel Cell Buses 

Fleet Mileage 171,359 16,708

 

Total Engine/Fuel-Related Systems (ATA VMRS 27, 30, 31, 32, 33, 41, 42, 43, 44, 45) 

Parts Cost 11,737.99 2,381.59

Labor Hours 491.6 973.6

Average Labor Cost 24,577.50 48,680.00

Total Cost (for system) 36,315.49 51,061.59

Total Cost (for system) per Bus 7,263.10 17,020.53

Total Cost (for system) per Mile 0.21 3.06

 

Exhaust System Repairs (ATA VMRS 43) 

Parts Cost 86.97 0.00

Labor Hours 100.4 0.0

Average Labor Cost 5,020.00 0.00

Total Cost (for system) 5,106.97 0.00

Total Cost (for system) per Bus 1,021.39 0.00

Total Cost (for system) per Mile 0.03 0.00

 

Fuel System Repairs (ATA VMRS 44) 

Parts Cost 3,226.63 1,042.00

Labor Hours 33.1 184.9

Average Labor Cost 1,652.50 9,245.00

Total Cost (for system) 4,879.13 10,287.00

Total Cost (for system) per Bus 975.83 3,429.00

Total Cost (for system) per Mile 0.03 0.62

 

Power Plant (Engine) Repairs (ATA VMRS 45) 

Parts Cost 3,924.18 299.93

Labor Hours 158.7 351.0

Average Labor Cost 7,935.00 17,550.00

Total Cost (for system) 11,859.18 17,849.93

Total Cost (for system) per Bus 2,371.84 5,949.98

Total Cost (for system) per Mile 0.07 1.07

 

Electric Propulsion Repairs (ATA VMRS 46) 

Parts Cost 0.00 0.00

Labor Hours 0.0 106.4

Average Labor Cost 0.00 5,320.00

Total Cost (for system) 0.00 5,320.00

Total Cost (for system) per Bus 0.00 1,773.33

Total Cost (for system) per Mile 0.00 0.32

 

50
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 463.33 0.00

Labor Hours 25.5 70.9

Average Labor Cost 1,275.00 3,545.00

Total Cost (for system) 1,738.33 3,545.00

Total Cost (for system) per Bus 347.67 1,181.67

Total Cost (for system) per Mile 0.01 0.21

 

Air Intake System Repairs (ATA VMRS 41) 

Parts Cost 312.79 509.50

Labor Hours 0.5 109.8

Average Labor Cost 25.00 5,490.00

Total Cost (for system) 337.79 5,999.50

Total Cost (for system) per Bus 67.56 1,999.83

Total Cost (for system) per Mile 0.00 0.36

 

Cooling System Repairs (ATA VMRS 42) 

Parts Cost 1,895.65 530.16

Labor Hours 84.4 141.1

Average Labor Cost 4,217.50 7,055.00

Total Cost (for system) 6,113.15 7,585.16

Total Cost (for system) per Bus 1,222.63 2,528.39

Total Cost (for system) per Mile 0.04 0.45

 

Hydraulic System Repairs (ATA VMRS 65) 

Parts Cost 0.00 0.00

Labor Hours 0.0 0.0

Average Labor Cost 0.00 0.00

Total Cost (for system) 0.00 0.00

Total Cost (for system) per Bus 0.00 0.00

Total Cost (for system) per Mile 0.00 0.00

 

General Air System Repairs (ATA VMRS 10) 

Parts Cost 933.50 0.00

Labor Hours 74.4 0.0

Average Labor Cost 3,720.00 0.00

Total Cost (for system) 4,653.50 0.00

Total Cost (for system) per Bus 930.70 0.00

Total Cost (for system) per Mile 0.03 0.00

 

51
Breakdown of Maintenance Costs by Vehicle System (continued)

 Diesel Buses Fuel Cell Buses 

Brake System Repairs (ATA VMRS 13)

Parts Cost 346.28 0.00

Labor Hours 74.2 22.0

Average Labor Cost 3,710.00 1,100.00

Total Cost (for system) 4,056.28 1,100.00

Total Cost (for system) per Bus 811.26 366.67

Total Cost (for system) per Mile 0.02 0.07

Transmission Repairs (ATA VMRS 27) 

Parts Cost 1,828.44 0.00

Labor Hours 89.1 9.5

Average Labor Cost 4,452.50 475.00

Total Cost (for system) 6,280.94 475.00

Total Cost (for system) per Bus 1,256.19 158.33

Total Cost (for system) per Mile 0.04 0.03

 

Inspections Only – No Parts Replacements (101) 

Parts Cost 0.00 0.00

Labor Hours 296.3 216.6

Average Labor Cost 14,815.00 10,830.00

Total Cost (for system) 14,815.00 10,830.00

Total Cost (for system) per Bus 2,963.00 3,610.00

Total Cost (for system) per Mile 0.09 0.65

 

Cab, Body, and Accessories Systems Repairs 

(ATA VMRS 02-Cab and Sheet Metal, 50-Accessories, 71-Body) 

Parts Cost 7,150.35 0.00

Labor Hours 255.8 130.6

Average Labor Cost 12,787.50 6,530.00

Total Cost (for system) 19,937.85 6,530.00

Total Cost (for system) per Bus 3,987.57 2,176.67

Total Cost (for system) per Mile 0.12 0.39

 

HVAC System Repairs (ATA VMRS 01) 

Parts Cost 647.82 7.50

Labor Hours 40.9 17.5

Average Labor Cost 2,042.50 875.00

Total Cost (for system) 2,690.32 882.50

Total Cost (for system) per Bus 538.06 294.17

Total Cost (for system) per Mile 0.02 0.05

 

52
Breakdown of Maintenance Costs by Vehicle System (continued)

 Diesel Buses Fuel Cell Buses 

Lighting System Repairs (ATA VMRS 34)

Parts Cost 1,473.89 0.00

Labor Hours 37.4 4.0

Average Labor Cost 1,870.00 200.00

Total Cost (for system) 3,343.89 200.00

Total Cost (for system) per Bus 668.78 66.67

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 7,966.52 0.00

Labor Hours 130.9 1.0

Average Labor Cost 6,545.00 50.00

Total Cost (for system) 14,511.52 50.00

Total Cost (for system) per Bus 2,902.30 16.67

Total Cost (for system) per Mile 0.08 0.00

 

Axle, Wheel, and Drive Shaft Repairs (ATA VMRS 11-Front Axle, 18-Wheels, 22-Rear Axle, 24-

Drive Shaft) 

Parts Cost 48.29 9.90

Labor Hours 11.2 4.5

Average Labor Cost 560.00 225.00

Total Cost (for system) 608.29 234.90

Total Cost (for system) per Bus 121.66 78.30

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 0.02

53
Notes

1. 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 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 engine/fuel-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. 

54
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PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ORGANIZATION.

1. REPORT DATE (DD-MM-YYYY)

March 2006 

2. REPORT TYPE

Technical Report 

3. DATES COVERED (From - To)

March 2005-October 2005 

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: Preliminary Evaluation 

Results 

5c. PROGRAM ELEMENT NUMBER

5d. PROJECT NUMBER

NREL/TP-540-39365 

5e. TASK NUMBER

HF65.8200 

6. AUTHOR(S)

K. Chandler and L. Eudy 

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National Renewable Energy Laboratory 

1617 Cole Blvd. 

Golden, CO 80401-3393 

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NREL/TP-540-39365 

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14. ABSTRACT (Maximum 200 Words)

Report provides preliminary results from an evaluation of prototype fuel cell transit buses operating at Santa Clara 

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15. SUBJECT TERMS

Hydrogen; fuel cell; transit buses; demonstration; evaluation; Santa Clara Valley Transporation Authority; San Mateo 

County Transit District 

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