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

Office of Energy Efficiency & Renewable Energy

National Renewable Energy Laboratory 

Innovation for Our Energy Future 

Alameda-Contra Costa Transit District 

(AC Transit) 

Fuel Cell Transit Buses: 

Third Evaluation Report 

Appendices

Kevin Chandler, Battelle 

Leslie Eudy, National Renewable Energy Laboratory 

Link to Report

Technical Report 

NREL/TP-560-43545-2 

July 2008 

NREL is operated by Midwest Research Institute ● Battelle Contract No. DE-AC36-99-GO10337 
Alameda-Contra Costa Transit District 

(AC Transit) 

Fuel Cell Transit Buses: 

Third Evaluation Report 

Appendices

Kevin Chandler, Battelle 

Leslie Eudy, National Renewable Energy Laboratory 

Prepared under Task No. H270.8200 

Technical Report 

NREL/TP-560-43545-2 

July 2008 

National Renewable Energy Laboratory

1617 Cole Boulevard, Golden, Colorado 80401-3393 

303-275-3000 • www.nrel.gov 

Operated for the U.S. Department of Energy 

Office of Energy Efficiency and Renewable Energy 

by Midwest Research Institute • Battelle 

Contract No. DE-AC36-99-GO10337
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Contents 

Appendix A: AC Transit Description

Appendix B: Evaluation Bus Technology Descriptions

Appendix C: Evaluation Infrastructure Description

Appendix D: NREL Transit Bus Evaluation Activities

Appendix E: Fleet Summary Statistics

Appendix F: Fleet Summary Statistics – SI Units

 iii
Introduction to the Appendices 

NREL has reported evaluation results for fuel cell buses since 2003. These reports include 

background on the transit agency, the buses, infrastructure, and overall experience operating fuel 

cell buses. Several reports are planned for each evaluation site. The first data report typically 

includes extensive background material plus an analysis of the first round of data. Update reports 

follow the initial publication, focusing on the newest data analysis and lessons learned since the 

previous report. The authors would like to provide more focus on the data, without depriving 

new readers of the background and context on the transit agency and the technology. These 

appendices, referenced in the main report, are designed to provide the full background for the 

evaluation. They will be updated as new information is collected, but will contain the original 

background material from the first report. Both parts are downloaded separately. A Web link is 

provided on the cover to allow the reader to download the main report. 

All NREL publications on hydrogen and fuel cell buses are available at: 

http://www.nrel.gov/hydrogen/proj_fc_bus_eval.html 

 iv
Appendix A: AC Transit Description 

Host Site Profile 

The Alameda-Contra Costa Transit District1

 (AC Transit) provides public transit service in the 

East Bay area which includes Oakland, California. AC Transit was created in 1956, but public 

transit in Oakland dates as far back as 1869. The district is governed by a seven-member board 

of directors elected by East Bay voters. Five of these board members represent geographic 

wards while two are elected at-large. The AC 

Transit service area of 360 square miles includes 13 

cities and adjacent unincorporated areas in 

Alameda and Contra Costa counties. AC Transit 

operates 538 transit buses in peak service (717 

active buses in the fleet including paratransit) on 

more than 105 fixed routes and provides school bus 

service. In fiscal year 2005, annual ridership 

exceeded 68.9 million. Since 2000, AC Transit has 

developed and operates a fuel cell demonstration 

program called the HyRoad. With a goal of 

demonstrating the viability of an emission-free 

transit system, the HyRoad program includes 

operating fuel cell buses and passenger cars, on-site 

hydrogen production, fueling, and vehicle 

maintenance, and public education and safety 

training. 

Golden Gate Transit2 (GGT) is a participant in the AC Transit fuel cell bus demonstration. GGT 

is part of the Golden Gate Bridge, Highway, and Transportation District (GGBHTD), which is 

headquartered in San Francisco, California, and serves the North Bay area. GGBHTD includes 

GGT as well as the operation of the Golden Gate Bridge and the Golden Gate Ferry. GGT, 

which operates from San Rafael, California, a central location in its operating area, started fixedroute service in 1972 based on transportation planning aimed at reducing traffic congestion on 

the Golden Gate Bridge. GGT has 260 buses that operated 5.1 million miles in fiscal year 2005. 

Figure A-1 shows the AC Transit and GGT operating areas. 

AC Transit Fuel Cell Bus Program 

AC Transit’s interest in fuel cell buses started in October 1999, following a successful one-week 

demonstration of the Ballard P4 ZEbus on scheduled routes in the AC Transit service area. This 

preceded Ballard operating the bus for a one-year test at SunLine in 2000. Soon after, the 

California Air Resources Board (CARB) established a new fleet rule in February 2000 to 

significantly reduce emissions of existing and new transit buses in California. The rule set more 

stringent emissions standards for new urban bus engines and promoted advancement of the 

cleanest propulsion technologies – specifically, zero emission buses (ZEBs). This ruling 

required transit agencies to choose a compliance path – alternative fuel or diesel. 

 

1

AC Transit web site: www.actransit.org 2

Golden Gate Transit Web site: www.goldengate.org

 A-1
The deadline for choosing one of these compliance paths was later in 2000. AC Transit and 

GGT chose the diesel path. AC Transit reported that it did not choose the alternative fuel path 

because it worried about reliability and capital costs for operating an alternative fuel such as 

compressed natural gas (CNG). Fleets choosing the diesel path were required to reduce the fleet 

average emissions through methods such as purchasing the cleanest diesel engines and 

retrofitting existing diesel engines with emissions control devices such as diesel particulate filters 

(DPFs). All California transit agencies with 200 or more buses (including AC Transit and GGT) 

choosing the diesel path were subject to demonstrate (by 2003) and eventually procure ZEBs at a 

rate of 15% of all new bus purchases starting in model year 2008. 

Figure A-1. AC Transit and Golden Gate Transit operating area in California 

 A-2
AC Transit and GGT agreed in 2001 to partner in the training and operation of the fuel cell buses 

in order to meet the CARB requirements. AC Transit attempted to purchase fuel cell buses in 

2000 and early 2001. The agency received only one bid, which was eventually withdrawn by the 

vendor. AC Transit set out in 2001 to learn all that it could about fuel cell buses, including 

operating the Ballard P4/ZEbus for one week for testing, joining the California Fuel Cell 

Partnership (CaFCP), and operating the ISE/UTC Power ThunderPower 30-foot fuel cell bus 

during part of 2003 and 2004. 

During 2001-2002, AC Transit was looking for a new bus design to purchase for its planned Bus 

Rapid Transit (BRT) project. AC Transit’s next large purchase of diesel buses (approximately 

190 buses) was supplied by Van Hool through its distributor in the United States, ABC 

Companies. These new buses featured three doors for quick loading and unloading for the Rapid 

BRT service, which started in June 2003 with the San Pablo Rapid service. 

At the end of 2001, AC Transit started discussions with ISE Corp. about developing a new fuel 

cell bus design. In April 2002, negotiations were started for a sole source contract with ISE 

Corp. and UTC Power with plans to use the same Van Hool bus chassis as was used for the 

diesel buses; however, this project stalled during most of 2002. After a major meeting of the 

project partners coinciding with an American Public Transportation Association (APTA) 

meeting in Las Vegas in September 2002, the project was re-energized. The contract for the new 

fuel cell buses was revised in April 2003, and the project was back on track. This order included 

three new Van Hool fuel cell buses for AC Transit and one new Van Hool fuel cell bus for 

SunLine. Rather than using a standard diesel chassis, as was originally planned, Van Hool 

designed and constructed an entirely new chassis (based on the existing A330 bus design) that 

could more effectively accommodate fuel cell and hybrid system components. 

This new contract had several changes and the delays now required that the CARB deadline for 

demonstrating fuel cell buses be postponed. The first fuel cell bus was delivered to AC Transit 

in October 2005, and the other two AC Transit buses arrived in December 2005. The on-site 

hydrogen fueling station from Chevron was commissioned on March 13, 2006, and the three fuel 

cell buses went into service on March 20, 2006. 

The HyRoad – Once the fuel cell buses were on order and being manufactured, AC Transit got to 

work putting together its hydrogen future and vision for its hydrogen fuel cell program. This 

comprehensive fuel cell program (HyRoad) aims to demonstrate the viability of an emission-free 

transit system and features: 

• Three zero-emission hybrid-electric, hydrogen fuel cell buses 

• A fleet of fuel cell passenger vehicles (part of DOE’s Controlled Hydrogen Fleet and 

Infrastructure Demonstration and Validation Project) 

• On-site hydrogen production and fueling 

• On-site fleet maintenance 

• Ongoing, outside evaluation (this report and future reports) 

• Public education and safety training 

 A-3
 A-4

The partners for the fuel cell bus program at AC Transit include: 

• Van Hool Bus – manufacturer of the bus bodies and chassis 

• UTC Power of Connecticut – maker of the fuel cell power systems 

• ISE Corporation of San Diego – integrator of the fuel cell power systems and hybridelectric drive systems 

• Chevron Technology Ventures (a division of Chevron USA) – builder of the hydrogen 

fueling station at AC Transit’s East Oakland Division 

Funding for this project included more than $21 million from public agencies and private sector 

companies, as follows: 

• State of California – $8 million 

• CARB – $2.8 million 

• Bay Area Air Quality Management District (BAAQMD) – $1 million 

• Federal Transit Administration – $1 million 

• California Energy Commission – $1 million 

• DOE – $700,000 plus partial funding for the hydrogen station construction and operating 

expenses 

• AC Transit matching funds – $1.2 million 

• CALSTART-WestStart – $200,000 

• Chevron Technology Ventures – $2 million (matching funds) plus additional funding for 

capital and operating expenses 

• Miscellaneous contributions of more than $3 million 
Appendix B: Evaluation Bus Technology Descriptions 

Table B-1 provides bus system descriptions for the fuel cell and diesel buses that were studied in 

this evaluation. The prototype fuel cell bus in service at AC Transit (Figure B-1) was developed 

in collaboration between ISE Corporation1

, UTC Power2, and Van Hool3. AC Transit unveiled 

its hydrogen fuel station and hydrogen fuel cell buses on March 13, 2006. The buses started in 

passenger service on March 20, 2006. The purchase, manufacturing, and packaging of the Van 

Hool fuel cell buses took about two years and cost approximately $3.2 million each. 

The Van Hool diesel buses were ordered in 2002, with delivery in 2005. To provide a baseline, 

six of the diesel Van Hool buses were selected from the 21 buses of that type operating from the 

East Oakland Division. These six diesel buses are operated alongside the fuel cell buses. The 

diesel buses, one of which is pictured in Figure B-2, cost $323,000 each. 

The diesel and fuel cell buses at AC Transit are the same bus model, but the diesel buses are 

slightly older. The fuel cell bus is a little more than 8,000 lbs heavier than the diesel bus, and 

this has reduced the passenger capacity. The price of the fuel cell bus is essentially ten times 

more than the diesel bus. 

Table B-1. Fuel Cell and Diesel Bus System Descriptions 

Vehicle System Operation from East Oakland Division 

Fuel Cell Bus Diesel Bus 

Number of Buses 3 6 

Bus Manufacturer and Model Van Hool A330 Low Floor Van Hool A330 Low Floor 

Model Year 2005 2003 

Length/Width/Height 40 ft/102 in/139 in 40 ft/102 in/121 in 

GVWR/Curb Weight 43,240 lb/36,000 lb 40,800 lb/27,800 lb 

Wheelbase 228 in 235 in 

Passenger Capacity 

30 seated or 26 seated 

and two wheelchairs 

15 standing 

32 seated or 28 seated 

and two wheelchairs 

53 standing 

Engine Manufacturer and 

Model 

UTC Power 

PureMotion4

 120 Fuel Cell 

Power System 

Cummins ISL 

Rated Power 

Fuel cell power system: 

120 kW 

Two Electric Drive Motors: 

170 kW total (continuous) 

280 hp @ 2200 rpm 

Accessories Electrical Mechanical 

Emissions Equipment None Diesel Oxidation Catalyst 

Transmission/Retarder Gearbox/Flenders 

Regenerative braking 

Voith 

Integrated retarder 

Fuel Capacity 50 kg hydrogen 92 gal 

Bus Purchase Cost $3.2 million $323,000 

 

1

 ISE Corporation Web site: www.isecorp.com 2

 UTC Power Web site: www.utcpower.com 3

 Van Hool Web site: www.abc-companies.com/sales_vh.htm 4

 PureMotion is a registered trademark of UTC Power. 

 B-1
Figure B-1. AC Transit fuel cell bus 

Figure B-2. Diesel bus at AC Transit 

Table B-2 provides a description of some of the electric propulsion systems for the fuel cell 

buses. Note that the diesel buses are not a hybrid configuration and do not have regenerative 

braking or energy storage for the drive system. 

Table B-2. Additional Electric Propulsion System Descriptions 

Propulsion Systems Fuel Cell Bus

Manufacturer/Integrator ISE Corporation 

Hybrid Type Series, charge sustaining 

Drive System Siemens ELFA/ISE 

Propulsion Motor 2-AC induction, 85 kW each 

Energy Storage Battery – 3 modules/216 cells sodium/nickel chloride 

ZEBRA®; 53 kWh capacity 

Fuel Storage Eight, roof mounted, SCI, type 3 tanks; 5,000 psi rated 

Regenerative Braking Yes 

Fuel Cell Bus Propulsion System Description 

The fuel cell buses use the PureMotion 120 Fuel Cell Power System manufactured by UTC 

Power in a hybrid electric drive system designed by ISE. The Van Hool A330 transit bus chassis 

was redesigned to integrate the fuel cell system. The bus has a low floor from front to back and 

three doors for easy passenger boarding. 

 B-2
ISE’s hybrid system (Figure B-3) is a series configuration, meaning the fuel cell power system is 

not mechanically coupled to the drive axle. The fuel cell power system and energy storage 

system work together to provide power to two electric drive motors, which are coupled to the 

driveline through a combining gearbox. When the bus needs extra power, the fuel cell power 

system and energy storage provide power to the drive motors. When the power requirements of 

the bus are low, the fuel cell power system provides power and recharges the energy storage 

system. 

The hybrid system is also capable of regenerative braking, which captures the energy typically 

expended during braking and uses it to recharge the energy storage system. Each component of 

the propulsion system is carefully controlled through an ISE-developed operating system. The 

ISE hybrid system was designed to be flexible, enabling integration of a variety of powerplants 

and energy storage options. The buses at AC Transit have a fuel cell powerplant and three 

ZEBRA (sodium/nickel chloride) batteries5

 as the energy storage system. 

The primary power source for this hybrid system is UTC Power’s PureMotion 120 Fuel Cell 

Power System which produces 120 kW from its proton exchange membrane (PEM) fuel cell 

stacks. UTC Power’s fuel cells operate at near-ambient pressure, which eliminates the need for a 

compressor. This not only increases the efficiency of the system, but also results in very quiet 

operation. 

Figure B-3. ISE’s hybrid propulsion system 

 

5

 Web site: www.betard.co.uk/

 B-3
Appendix C: Evaluation Infrastructure Description 

AC Transit operates its bus fleet from four divisions – Richmond, Emeryville, East Oakland, and 

Hayward. To demonstrate fuel cell buses (FCBs), the fleet needed to install hydrogen fueling 

infrastructure at one of these bus operating divisions. As a diesel-path fleet, AC Transit had no 

prior experience with gaseous fuels. Joining the CaFCP provided an opportunity for the fleet to 

accelerate the learning curve and gain valuable hydrogen fuel experience before the FCBs were 

delivered. AC Transit’s first hydrogen-related project was in partnership with the CaFCP and 

Stuart Energy Systems (now Hydrogenics) to install an electrolyzer at the Richmond Division. 

This station was mainly intended as a satellite station for light-duty fuel cell vehicles (FCVs) 

being tested by the automotive partners of the CaFCP. This location, between Sacramento and 

San Francisco, was ideal to enable FCVs to travel between the two cities. In addition to the 

light-duty FCVs, AC Transit also used this station to fill the ThunderPower FCB during its 

demonstration. 

Oakland Energy Station1

AC Transit selected the East Oakland Division as the site for demonstrating its fleet of FCBs. 

This was due to its location in a light industrial area and because space was available for the 

added fueling infrastructure. AC Transit operates over 200 vehicles from this division, including 

the three FCBs, 21 40-ft diesel Van Hool buses, 41 paratransit shuttles, and six UC Berkeley 

vans. Of the buses at the site, 138 are required for peak service. 

In March 2004, AC Transit partnered with Chevron Technology Ventures to design and build a 

hydrogen energy station at the East Oakland Division. Plans for a station were already in 

process as part of the DOE light-duty FCV demonstration. Chevron leads one of the teams 

demonstrating FCVs and hydrogen infrastructure for the DOE project. AC Transit serves as one 

of the demonstration sites, operating a small fleet of Hyundai/Kia FCVs. 

As the FCB demonstration plans began to solidify, the project partners decided it would be cost 

effective to combine the needs for both demonstrations into one station. Construction on the 

station began in June 2005 and was completed by November. The station was operational by 

mid-December. On March 13, 2006, AC Transit and local officials formally inaugurated the 

Chevron - AC Transit Hydrogen Energy Station, kicking-off the demonstration project. All of 

the HyRoad project partners participated in the event, which included facility tours and a ribboncutting ceremony. 

Figure C-1 illustrates the overall station layout. The energy station at the East Oakland Division 

generates hydrogen through steam methane reformation in a three-step process: 

1. Hydrogen generation - Natural gas from a utility line is fed to a steam methane reformer 

that produces a hydrogen-rich output gas. This output gas, called reformate, is typically 

composed of 75% hydrogen and 20% carbon dioxide and other trace gases. 

2. Reformate compression – Hydrogen-rich reformate is compressed to approximately 125 

psi, as required for the purification step. 

 

1

 Information on the Chevron-AC Transit Hydrogen Energy Station was provided in part by Chevron Technology 

Ventures, a division of Chevron USA. 

 C-1
3. Purification – A pressure swing absorption unit purifies the reformate stream to 99.99% 

hydrogen, which is acceptable for use in PEM fuel cells. Excess gas is returned to the 

reformer for combustion. 

The station design includes two reformers that are capable of producing a total of 150 kg 

hydrogen per day. One of the reformers is a standard design (Figure C-2) and produces 

hydrogen through the three-step process outlined above. This reformer is intended to be the 

primary production reformer for hydrogen at the station. 

Chevron is using the second reformer, which is an advanced technology design, to investigate 

ways to further refine production methods and increase efficiency. For that second reformer, 

steps 1 and 2 are reversed: the natural gas is compressed to about 150 psi, and the reformer then 

generates hydrogen at the higher pressure. An advantage of this is that compressing natural gas 

takes less energy than compressing the hydrogen-rich reformate stream. Producing a reformer 

capable of operating at the higher pressure, however, will potentially increase the cost of that 

equipment. This may be offset by the reduced cost for the natural gas vs. reformate compressor. 

The demonstration will help Chevron determine the trade-offs between the increased efficiency 

of compressing natural gas and the change in equipment cost. 

Figure C-1. Chevron – AC Transit (Oakland) Hydrogen Energy Station overall layout 

The purified hydrogen is then compressed to 6,250 psi and stored in a series of cascade pressure 

vessels (Figure C-3). Total storage capacity at the station is 366 kg of hydrogen. The station is 

equipped with two dispensers that supply the compressed hydrogen to the buses and light-duty 

vehicles. The system connections monitor the tank-fill status and provide an appropriate fill at 

5,000 psi. The dispensing system is designed to enable simultaneous fills for two buses (or lightduty fuel cell vehicles). Figure C-4 shows the hydrogen fueling dispensers at the station. AC 

Transit’s agreement with Chevron includes all operation and maintenance of the station for two 

years. 

 C-2
Figure C-2 Primary reformer at Chevron – AC Transit Hydrogen Energy Station (75 kg/day) 

Figure C-3. Cascade hydrogen storage vessels at AC Transit station 

 C-3
Figure C-4. Dispenser at Chevron – AC Transit Energy Station 

The design of the station includes various safety devices to alert AC Transit and Chevron of any 

potential problems. These devices include hydrogen detectors, flame sensors, emergency stop 

buttons, and alarm indicator lights (Figure C-5). The alarm indicators reflect the condition of the 

station as follows: 

• Green light – normal operating conditions 

• Yellow light – a problem is occurring or has occurred 

• Red light – hazardous condition exists, evacuation from area required 

• Strobe and siren – fire condition, fire department notified 

Figure C-5. Condition indicator lights (left) and hydrogen flame sensor (right) 

at the Chevron – AC Transit Hydrogen Energy Station

 C-4
Maintenance Facility Modifications 

AC Transit chose to modify an existing facility to enable staff to maintain the hydrogen-fueled 

buses safely. The required modifications (~$1.5 million) were completed and the maintenance 

bay was cleared for use in January 2006. The selected bay was isolated from the rest of the 

facility by a firewall. There is space for servicing two buses at a time. Figure C-6 shows the bay 

with and without a fuel cell bus. 

Figure C-6. Modified maintenance bay at AC Transit East Oakland Division 

The detection system in the maintenance bay is configured to trigger specific actions if a leak or 

fire is detected. At 20% lower flammability limit (LFL), the garage doors automatically open, 

ventilation fans are turned on, the heating system is shut down, and the magnetic doors release. 

If a leak is detected at 40% LFL or a fire is detected, the fire department is automatically 

notified, all electrical power to the bay is disconnected (except for ventilation and emergency 

equipment), and a fire alarm is activated to signal evacuation of the building. These safety 

measures are all in place to ensure maximum protection for staff and facilities in case of a 

hydrogen-related incident. None have been recorded to date. 

Other safety features include: 

• Two-hour firewall 

• Ignition-free space heating system 

• Anti-static, non-skid, grounded floor covering 

• High Speed roll-up doors 

• Magnetic door release 

• Audiovisual strobe alarms 

 C-5
• Three-fan ventilation system capable of providing up to four to six air exchanges per hour 

• Class 1 Division 2 electrical classification 

Because the specially equipped maintenance bay is co-located with the rest of the maintenance 

building, maintenance staff is required to depressurize the buses prior to entering the facility. To 

accomplish this depressurization, the hydrogen in the tanks is vented down to 600 psi. The 

hydrogen removed from the vehicle is ultimately vented to the atmosphere in a controlled and 

safe manner. This decision to lower the fuel pressure in the vehicle was made early in the design 

process to reduce the overall cost of the facility modifications. The safety requirements for a 

facility capable of maintaining buses with full hydrogen tanks are more costly. Although 

capturing the vented hydrogen for future use is possible, early investigation showed it was not 

cost-effective using available methods. For a fleet of only three buses, the amount of hydrogen 

vented was deemed not significant enough to warrant the cost of the equipment to capture and 

reuse the fuel. 

In preparation for full-day fuel cell bus operation, AC Transit upgraded their electrical access for 

charging the ZEBRA batteries overnight to allow faster charging. These upgrades were 

completed in June 2007. Each fuel cell bus is plugged into a charge station (shown in Figure C7) overnight to balance the charge between batteries, top off the charge, and provide heat for the 

batteries and freeze protection for the fuel cell when temperatures are 2°C or less. 

Figure C-7. Fuel cell bus/battery charging station at AC Transit 

 C-6
Appendix D: NREL Transit Bus Evaluation Activities 

Under funding from the Department of Energy (DOE) and in coordination with the Federal 

Transit Administration (FTA), the National Renewable Energy Laboratory (NREL) has been 

evaluating alternative fuel transit buses since the early 1990s. In 1996, DOE and NREL 

completed an evaluation of transit buses at eight transit agencies that included six different 

alternative fuels. As part of this alternative fuel transit bus evaluation, NREL and Battelle 

(NREL’s contractor for this effort) developed a customized data collection and evaluation 

protocol. This protocol has evolved over time, but is still based on the original effort. 

NREL first began evaluating hydrogen-fueled transit buses in 2000 with SunLine Transit 

Agency. Since that time, NREL has published reports on fuel cell bus (FCB) performance and 

fleet experience for several transit agencies in the United States. These evaluations were funded 

under the DOE’s Hydrogen, Fuel Cells & Infrastructure Technologies (HFCIT) Program1, which 

is focused on addressing the technical challenges and accelerating the development and 

successful market introduction of hydrogen technologies. Technology validation is one of the 

key elements of this program.2

 NREL supports DOE’s Technology Validation activity by 

evaluating hydrogen and fuel cell vehicles in parallel with hydrogen infrastructure to determine 

the current status of the technology and assess the progress toward technology readiness. 

While DOE has not funded the direct development of fuel cell buses, it has provided funding to 

NREL to conduct data collection, analysis, and reporting of existing FCB project evaluation 

results under its Technology Validation activity. The current hydrogen transit bus evaluations 

include four active projects and two that were completed in the last few years. 

In 2006, FTA initiated its newest development program, the National Fuel Cell Bus Program 

(NFCBP)3. The NFCBP was established as part of the Safe, Accountable, Flexible, Efficient 

Transportation Equity Act: a Legacy for Users (SAFETEA-LU) transportation authorization. The 

NFCBP program designates $49 million in funding for 2006 through 2009 to help develop 

commercially viable fuel cell buses and technologies. The FTA competitively selected three 

nonprofit organizations—the Center for Transportation and the Environment (CTE), the 

Northeast Advanced Vehicle Consortium (NAVC), and WestStart-CALSTART—to administer 

projects under the program. The FTA selected 14 separate projects in all, including eight planned 

demonstration projects. 

The FTA is collaborating with DOE and NREL to ensure that data are collected on all fuel cell 

bus demonstrations under the program. FTA has tasked NREL with evaluating the fuel cell bus 

demonstrations for the NFCBP. NREL uses the standard data collection and analysis protocol 

established for DOE heavy-duty vehicle evaluations as described in this plan. In May 2008, 

NREL published Hydrogen and Fuel Cell Transit Bus Evaluations: Joint Evaluation Plan for the 

U.S. Department of Energy and the Federal Transit Administration, which outlines the 

 

1

 DOE HFCIT Web site: www1.eere.energy.gov/hydrogenandfuelcells/ 2

 DOE Multi-Year Research, Development and Demonstration Plan, 

www1.eere.energy.gov/hydrogenandfuelcells/mypp/ 3

 FTA Bus Research and Testing Web site: http://www.fta.dot.gov/assistance/technology/research_4578.html 

 D-1
methodology for these evaluations4

. Table D-1 provides an overview of all the FCB evaluation 

projects planned under both DOE and FTA funding. The projects are separated by funding 

agency, however for the NFCBP evaluation sites, any detailed data collection and analysis of the 

fuel cell system or infrastructure will be funded by DOE. Table D-2 provides more details and 

status for the evaluation sites funded solely by DOE. Additional details on the eight NFCBP 

demonstrations sites funded by FTA are listed in Table D-3. FTA is also considering additional 

funding for one or two sites beyond the NFCBP sites, but that has not been determined. 

Table D-1. Summary of Hydrogen Evaluations for DOE and FTA5

34123412341234

AC Transit /Oakland CA HyRoad

AC Transit /Oakland CA AC Transit CA ZEB 2009

SunLine /Thousand Palms CA FCB/HHICE

SunLine /Thousand Palms CA FCB Ext. Service

SunLine /Thousand Palms CA Advanced FCB Project

CTTRANSIT /Hartford CT CTTRANSIT FCB Demo

Hickam AFB /Honolulu HI Air Force FCV Demo

VTA /San Jose CA VTA CA ZEB 2009

AC Transit /Oakland CA Accelerated Testing

SunLine /Thousand Palms CA American FCB Demo

CTTRANSIT /Hartford CT CT Hybrid FCB Demo

Columbia /Site 2/ CTTRANSIT SC/CT Dual Variable Output Hybrid FCB

Logan Airport /Boston MA MA H2 FCB Fleet

TBD/NY NY Lightweight FCB Demo

TBD/NY NY Hydroelectric H2 Powered FCB

SFMTA /San Francisco CA FC APU Hybrid

Site/Locations State

DOE 

Tech. Validation

FTA National Fuel 

Cell Bus Program*

Eval. 

Funding

2007 2008 2009 2010

Color coded by geographic area * Detailed data collection and analysis funded by DOE 

Table D-2. DOE/NREL Heavy Vehicle Fuel Cell/Hydrogen Evaluations 

Fleet Vehicle/Technology Number Evaluation Status

SunLine Transit Agency 

(Thousand Palms, CA) 

Van Hool/UTC Power fuel cell hybrid 

transit bus integrated by ISE Corp. 1 Extended testing with updated 

fuel cell system, In process 

Connecticut Transit (Hartford, 

CT) 

Van Hool/UTC Power fuel cell hybrid 

transit bus integrated by ISE Corp. 1 Bus in operation; data 

collection started 

U.S. Air Force/Hickam Air Force 

Base (Honolulu, HI) 

Shuttle bus: Hydrogenics and Enova, 

battery-dominant fuel cell hybrid 1 Shuttle bus in operation; data 

collection started 

Delivery van: Hydrogenics and Enova, 

fuel cell hybrid 1 Van in operation; data collection started 

Completed Evaluations 

SunLine Transit Agency 

(Thousand Palms, CA) 

New Flyer/ISE Corp. hydrogen internal 

combustion engine transit bus 1 Complete; results reported in 

Feb. 2007, Sep. 2007, and 

June 2008 Van Hool/UTC Power fuel cell hybrid 

transit bus integrated by ISE Corp. 1 

Alameda-Contra Costa Transit 

District (Oakland, CA) 

Van Hool/UTC Power fuel cell hybrid 

transit bus integrated by ISE Corp. 3 

Complete; results reported in 

Mar. 2007, Oct. 2007, and 

July 2008 

Santa Clara VTA, (San Jose, CA) 

and San Mateo (San Carlos, CA) Gillig/Ballard fuel cell transit bus 3 Complete and reported in 2006 

SunLine Transit Agency 

(Thousand Palms, CA) 

ThunderPower hybrid fuel cell transit 

bus; ISE Corp./ UTC Power 1 Complete and reported in 2003 

 

4

 Hydrogen and Fuel Cell Transit Bus Evaluations: Joint Evaluation Plan for the U.S. Department of Energy and the 

Federal Transit Administration, NREL/MP-560-42781, May 2008, http://www.nrel.gov/hydrogen/pdfs/42781-1.pdf 5

 For current version of the summary table, see link: http://www.nrel.gov/hydrogen/proj_fc_bus_eval.html 

 D-2
Table D-3. Summary of FTA NFCBP Demonstration Projects 

Project Description

Dual Variable Output Fuel Cell Hybrid 

Bus Validation and Testing 

(CTE) 

Proterra will develop a battery-dominant 35-ft plug-in hybrid 

fuel cell bus (Hydrogenics) and demonstrate in Columbia, SC, 

and cities in CT 

Nutmeg/Connecticut Fuel Cell Bus 

Program 

(NAVC) 

UTC Power and NAVC are leading a team to develop and 

demonstrate an advanced version hybrid 40-ft fuel cell buses; 

enhanced UTC Power 120 kW PEM fuel cell with upgraded 

seals, catalysts, bipolar plates, balance of plant 

Lightweight Fuel Cell Hybrid Bus 

(NAVC) 

GE led team to develop an advanced propulsion system 

integrated with a lightweight bus platform for field evaluation 

focused on advanced battery technologies for lower cost 

Massachusetts Hydrogen Fuel Cell 

Powered Bus Fleet 

(NAVC) 

Advanced bus development and in-service demonstration; 

integrate Nuvera 82 kW fuel cell with drive system from ISE 

Corp. and advanced energy storage; demonstration effort 

includes Nuvera’s novel PowerTap fueling infrastructure

Hydroelectric Hydrogen Powered FCB 

Program 

(NAVC) 

The project team led by the New York Power Authority will 

develop and demonstrate two 40-ft buses for operation in 

upstate New York for up to 2 years; Next-generation Ballard 

HD6 fuel cell module (150 kW) in hybrid configuration with ISE 

drive and ultracapacitors or batteries 

American Advanced Fuel Cell Bus 

Program 

(WestStart-CALSTART)

A team led by SunLine will design and demonstrate 40-ft fuel 

cell bus with design improvements that meets FTA buy 

America requirements (New Flyer chassis, ISE hybrid drive 

system, and UTC Power fuel cell system); in-service 

evaluation in hot desert climate 

Compound Fuel Cell Hybrid Bus for 

2010 

(WestStart-CALSTART) 

A team led by BAE will develop 40-ft hybrid bus with fuel cell 

auxiliary power unit coupled with diesel engine; demonstrate 

for one year at San Francisco MTA; small Hydrogenics PEM 

fuel cell (12 kW twin or 16 kW), BAE Systems drive, 

electrically driven accessories, advanced energy storage

AC Transit HyRoad: Commercialization 

of Fuel Cells for Public Transit 

(WestStart-CALSTART)

Accelerated testing of existing fuel cell buses; Team includes 

Van Hool (bus chassis), ISE (hybrid drive system), and UTC 

Power (fuel cell system)

Overall Evaluation Objectives 

The objectives of the DOE and FTA evaluations are to provide comprehensive, unbiased 

evaluation results of fuel cell and hydrogen bus development and performance compared to 

conventional baseline vehicles when available and appropriate. Baseline vehicles are typically 

diesel buses or occasionally compressed natural gas (CNG). These evaluations also include 

information on the development and performance of hydrogen infrastructure, and descriptions of 

the facility modifications required for safe operation of hydrogen-fueled vehicles. 

The DOE and FTA demonstration and evaluation programs have two major goals: 

• Provide credible data analysis results to the transit bus and fuel cell industries that go 

beyond “proof of concept” for fuel cell transit buses and infrastructure. 

• Provide results focused on performance and use including progress over time and 

experience from integrating vehicle systems, operations, and facilities for the fuel cell 

transit buses and supporting infrastructure. 

 D-3
 D-4

DOE and FTA have both cited the lack of data and analysis results in real-world service as a 

challenge for moving the technology forward. These evaluations have proved useful for a 

variety of groups including transit operators considering the technology for future procurements, 

manufacturers needing to understand the status of the technology for transit applications, and 

government agencies making policy decisions or determining future research needs. 
Appendix E: Fleet Summary Statistics 

Fleet Summary Statistics: Alameda-Contra Costa Transit District (AC Transit)

Diesel and FCB Study Groups 

Fleet Operations and Economics

Fuel Cell Diesel 

Number of Vehicles 3 6

Period Used for Fuel and Oil Op Analysis 4/06-12/07 1/07-12/07

Total Number of Months in Period 21 12

Fuel and Oil Analysis Base Fleet Mileage 62,191 264,575

Period Used for Maintenance Op Analysis 4/06-12/07 4/06-12/07

Total Number of Months in Period 21 21

Maintenance Analysis Base Fleet Mileage 62,191 389,473

Average Monthly Mileage per Vehicle 987 3,091

Availability 55% N/A

Fleet Fuel Usage in Diesel Gal/H2 kg 9,982 62,976

Roadcalls 48 85

RCs MBRC 1,296 4,582

Propulsion Roadcalls 41 37

Propulsion MBRC 1,517 10,526

 

Fleet Miles/kg Hydrogen 6.23 

(1.13 kg H2/gal Diesel Fuel) 

Representative Fleet MPG (energy equiv.) 7.04 4.20

 

Hydrogen Cost per kg 8.00 

Diesel Cost per Gallon 2.27

Fuel Cost per Mile 1.28 0.54

 

Total Scheduled Repair Cost per Mile 0.20 0.09

Total Unscheduled Repair Cost per Mile 0.37 0.35

Total Maintenance Cost per Mile 0.57 0.44

 

Total Operating Cost per Mile 1.85 0.98

Maintenance Costs

 Fuel Cell Diesel 

Fleet Mileage 62,191 389,473

 

Total Parts Cost 11,024.59 103,901.41

Total Labor Hours 481.8 1346.8

Average Labor Cost (@ $50.00 per hour) 24,090.00 67,340.00

 

Total Maintenance Cost 35,114.59 171,241.41

Total Maintenance Cost per Bus 11,704.86 28,540.24

Total Maintenance Cost per Mile 0.57 0.44

 E-1
Breakdown of Maintenance Costs by Vehicle System

Fuel Cell Diesel 

Fleet Mileage 62,191 389,473

 

Total Propulsion-Related Systems (ATA VMRS 27, 30, 31, 32, 33, 41, 42, 43, 44, 45, 46, 65) 

Parts Cost 887.52 25,191.46

Labor Hours 97.8 306.6

Average Labor Cost 4,887.50 15,328.50

Total Cost (for system) 5,775.02 40,519.96

Total Cost (for system) per Bus 1,925.01 6,753.33

Total Cost (for system) per Mile 0.09 0.10

 

Exhaust System Repairs (ATA VMRS 43) 

Parts Cost 0.00 5,258.08

Labor Hours 0.0 33.6

Average Labor Cost 0.00 1,677.50

Total Cost (for system) 0.00 6,935.58

Total Cost (for system) per Bus 0.00 1,155.93

Total Cost (for system) per Mile 0.00 0.02

 

Fuel System Repairs (ATA VMRS 44) 

Parts Cost 0.00 3,238.31

Labor Hours 11.4 49.8

Average Labor Cost 575.50 2,490.00

Total Cost (for system) 575.50 5,728.31

Total Cost (for system) per Bus 190.17 954.72

Total Cost (for system) per Mile 0.01 0.02

 

Power Plant (Engine) Repairs (ATA VMRS 45) 

Parts Cost 126.68 7,689.35

Labor Hours 15.0 98.2

Average Labor Cost 748.00 4,909.50

Total Cost (for system) 874.68 12,598.85

Total Cost (for system) per Bus 291.56 2,099.81

Total Cost (for system) per Mile 0.02 0.03

 

Electric Propulsion Repairs (ATA VMRS 46) 

Parts Cost 238.39 0.00

Labor Hours 66.4 0.0

Average Labor Cost 3,319.00 0.00

Total Cost (for system) 3,557.39 0.00

Total Cost (for system) per Bus 1,185.80 0.00

Total Cost (for system) per Mile 0.06 0.00

 

 E-2
Breakdown of Maintenance Costs by Vehicle System (continued)

 Fuel Cell Diesel 

Electrical System Repairs (ATA VMRS 30-Electrical General, 31-Charging, 32-Cranking, 33-

Ignition)

Parts Cost 220.19 1,888.56

Labor Hours 2.0 45.8

Average Labor Cost 100.00 2,289.00

Total Cost (for system) 320.19 4,177.56

Total Cost (for system) per Bus 106.73 696.26

Total Cost (for system) per Mile 0.01 0.01

 

Air Intake System Repairs (ATA VMRS 41) 

Parts Cost 294.45 1,408.08

Labor Hours 0.0 0.0

Average Labor Cost 0.00 0.00

Total Cost (for system) 294.45 1,408.08

Total Cost (for system) per Bus 98.15 234.68

Total Cost (for system) per Mile 0.01 0.00

 

Cooling System Repairs (ATA VMRS 42) 

Parts Cost 7.80 5,041.17

Labor Hours 1.0 70.5

Average Labor Cost 50.00 3,525.00

Total Cost (for system) 57.80 8,566.17

Total Cost (for system) per Bus 19.27 1,427.70

Total Cost (for system) per Mile 0.00 0.02

 

Hydraulic System Repairs (ATA VMRS 65) 

Parts Cost 0.00 134.76

Labor Hours 0.0 6.0

Average Labor Cost 0.00 300.00

Total Cost (for system) 0.00 434.76

Total Cost (for system) per Bus 0.00 72.46

Total Cost (for system) per Mile 0.00 0.00

 

General Air System Repairs (ATA VMRS 10) 

Parts Cost 12.34 385.21

Labor Hours 0.0 14.8

Average Labor Cost 0.00 737.50

Total Cost (for system) 12.34 1,122.71

Total Cost (for system) per Bus 4.11 187.12

Total Cost (for system) per Mile 0.00 0.00

 

 E-3
Breakdown of Maintenance Costs by Vehicle System (continued)

 Fuel Cell Diesel 

Brake System Repairs (ATA VMRS 13) 

Parts Cost 4,098.95 26,060.20

Labor Hours 2.0 117.2

Average Labor Cost 100.00 5,859.50

Total Cost (for system) 4,198.95 31,919.70

Total Cost (for system) per Bus 1,399.65 5,319.95

Total Cost (for system) per Mile 0.07 0.08

Transmission Repairs (ATA VMRS 27) 

Parts Cost 0.00 533.15

Labor Hours 2.0 2.8

Average Labor Cost 100.00 137.50

Total Cost (for system) 100.00 670.65

Total Cost (for system) per Bus 33.33 111.78

Total Cost (for system) per Mile 0.00 0.00

 

Inspections Only – No Parts Replacements (101) 

Parts Cost 0.00 0.00

Labor Hours 139.8 555.5

Average Labor Cost 6,987.50 27,774.00

Total Cost (for system) 6,987.50 27,774.00

Total Cost (for system) per Bus 2,329.17 4,629.00

Total Cost (for system) per Mile 0.11 0.07

 

Cab, Body, and Accessories Systems Repairs 

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

Parts Cost 5,431.87 44,983.39

Labor Hours 231.6 223.8

Average Labor Cost 11,579.50 11,192.00

Total Cost (for system) 17,011.37 56,175.39

Total Cost (for system) per Bus 5,670.46 9,362.57

Total Cost (for system) per Mile 0.28 0.14

 

HVAC System Repairs (ATA VMRS 01) 

Parts Cost 0.00 1,089.23

Labor Hours 7.6 12.9

Average Labor Cost 380.00 644.00

Total Cost (for system) 380.00 1,733.23

Total Cost (for system) per Bus 126.67 288.87

Total Cost (for system) per Mile 0.01 0.01

 

 E-4
Breakdown of Maintenance Costs by Vehicle System (continued)

 Fuel Cell Diesel 

Lighting System Repairs (ATA VMRS 34)

Parts Cost 266.41 755.67

Labor Hours 1.6 20.4

Average Labor Cost 80.50 1,022.00

Total Cost (for system) 346.91 1,777.67

Total Cost (for system) per Bus 115.64 296.28

Total Cost (for system) per Mile 0.01 0.01

 

Frame, Steering, and Suspension Repairs (ATA VMRS 14-Frame, 15-Steering, 16-Suspension) 

Parts Cost 138.88 3,425.44

Labor Hours 1.5 74.6

Average Labor Cost 75.00 3,730.50

Total Cost (for system) 213.88 7,155.94

Total Cost (for system) per Bus 71.29 1,192.66

Total Cost (for system) per Mile 0.00 0.02

 

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

Drive Shaft) 

Parts Cost 188.62 2,010.78

Labor Hours 0.0 16.0

Average Labor Cost 0.00 797.50

Total Cost (for system) 188.62 2,808.28

Total Cost (for system) per Bus 62.87 468.05

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 4.1

Average Labor Cost 0.00 204.50

Total Cost (for system) 0.00 204.50

Total Cost (for system) per Bus 0.00 34.08

Total Cost (for system) per Mile 0.00 0.00

 E-5
 E-6

Notes

1. To compare the hydrogen fuel dispensed and fuel economy to diesel, the hydrogen dispensed 

was also converted into diesel energy equivalent gallons. The general energy conversions are as 

follows, actual energy content will vary by location: 

Lower heating value (LHV) for hydrogen = 51,532 Btu/lb 

LHV for diesel = 128,400 Btu/lb 

1 kg = 2.205 * lb 

51,532 Btu/lb * 2.205 lb/kg = 113,628 Btu/kg 

Diesel/hydrogen = 128,400 Btu/gallon / 113,628 Btu/kg = 1.13 kg/diesel gallon 

2. The propulsion-related systems were chosen to include only those systems of the vehicles that 

could be directly impacted by the selection of a fuel/advanced technology. 

3. ATA VMRS coding is based on parts that were replaced. If there was no part replaced in a given 

repair, then the code was chosen by the system being worked on. 

4. In general, inspections (with no part replacements) were only included in the overall totals (not by 

system). 101 was created to track labor costs for PM inspections. 

5. ATA VMRS 02-Cab and Sheet Metal represents seats, doors, etc.; ATA VMRS 50-Accessories 

represents things like fire extinguishers, test kits, etc.; ATA VMRS 71-Body represents mostly 

windows and windshields. 

6. Average labor cost is assumed to be $50 per hour. 

7. Warranty costs are not included. 
Appendix F: Fleet Summary Statistics – SI Units 

Fleet Summary Statistics: Alameda-Contra Costa Transit District (AC Transit)

Diesel and FCB Study Groups 

Fleet Operations and Economics

Fuel Cell Diesel 

Number of Vehicles 3 6

Period Used for Fuel and Oil Op Analysis 4/06-12/07 1/07-12/07

Total Number of Months in Period 21 12

Fuel and Oil Analysis Base Fleet Kilometers 100,084 425,781

Period Used for Maintenance Op Analysis 4/06-12/07 4/06-12/07

Total Number of Months in Period 21 21

Maintenance Analysis Base Fleet Kilometers 100,084 626,779

Average Monthly Kilometers per Vehicle 1,589 4,974

Availability 55% N/A

Fleet Fuel Usage in Diesel L/H2 kg 9,982 238,364

Roadcalls 48 85

Kilometers between roadcalls (KBRC) 2,085 7,374

Propulsion Roadcalls 41 37

Propulsion KBRC 2,441 16,940

 

Fleet kg Hydrogen/100 km 9.97 

Representative Fleet MPG (L/100 km) 33.41 55.98

 

Hydrogen Cost per kg 8.00 

Diesel Cost per Liter 0.60

Fuel Cost per Kilometer 0.80 0.34

 

Total Scheduled Repair Cost per Kilometer 0.12 0.06

Total Unscheduled Repair Cost per Kilometer 0.23 0.21

Total Maintenance Cost per Kilometer 0.35 0.27

 

Total Operating Cost per Kilometer 1.15 0.61

Maintenance Costs

 Fuel Cell Diesel 

Fleet Kilometers 100,084 626,779

 

Total Parts Cost 11,024.59 103,901.41

Total Labor Hours 481.8 1346.8

Average Labor Cost (@ $50.00 per hour) 24,090.00 67,340.00

 

Total Maintenance Cost 36,114.59 171,241.41

Total Maintenance Cost per Bus 11,704.86 28,540.24

Total Maintenance Cost per Kilometer 0.35 0.27

 F-1
F1147-E(09/2007) 

REPORT DOCUMENTATION PAGE Form Approved 

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1. REPORT DATE (DD-MM-YYYY)

July 2008 

2. REPORT TYPE

Technical Report 

3. DATES COVERED (From - To)

 

4. TITLE AND SUBTITLE

Alameda-Contra Costa Transit District (AC Transit) 

Fuel Cell Transit Buses: Third Evaluation Report and Appendices 

5a. CONTRACT NUMBER

DE-AC36-99-GO10337 

5b. GRANT NUMBER

5c. PROGRAM ELEMENT NUMBER

6. AUTHOR(S)

K. Chandler and L. Eudy 

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NREL/TP-560-43545 

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H2708200 

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13. SUPPLEMENTARY NOTES

14. ABSTRACT (Maximum 200 Words)

This report describes operations at Alameda-Contra Costa Transit district for three protoype fuel cell buses and six 

diesel buses operating from the same location. 

15. SUBJECT TERMS

hydrogen; buses; transit; demonstration; AC Transit; Alameda-Contra Costa; HyRoad; FTA 

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