Road 4 - Medium- and Heavy-Duty Vehicle RDD and D

Road 4 - Medium- and Heavy-Duty Vehicle RDD and D

In conjunction with our Federal partners conducting light-duty vehicle research, DOT is the designated lead agency for medium and heavy- duty vehicle RDD&D. Based on DOT's positive experience with other alternative fuels, these vehicles may be the first to be effectively deployed and anchor the success of the hydrogen economy. In particular, DOT is interested in exploring the use of hydrogen for public transit buses and for certain types of waterborne vessels. This includes shuttles, ferries, and deepwater passenger and freight vessels. Hydrogen may be appropriate for primary propulsion and/or on-board auxiliary electrical generation.

Anticipated Long-Term Outcomes

The long-term outcome for Road 4 is the commercial deployment of hydrogen fueled medium and heavy-duty vehicles. The fleet operation of these vehicles, especially transit buses, is conducive to early commercial introduction of new technologies. This will be accomplished through continued RDD&D efforts in buses, medium and heavy-duty trucks, rail vehicles, and marine vessels.

Challenges and Requirements

The operating and market characteristics of medium- and heavy-duty vehicles are substantially different from the light-duty vehicles operated by the general public. The performance and cost aspects of the heavier vehicles make them more conducive to early use of hydrogen fuel technology. The activities of Roads 1 through 3 can be leveraged to support the development and demonstration activities of DOT operating administrations.

These operating and market characteristics present new opportunities and challenges for the hydrogen program. For the most part, medium- and heavy-duty vehicles operate in a tighter integrated and regulated system than light-duty vehicles. Development and demonstration activities need to address the challenges of these demanding environments in order to ensure that these new technologies do not compromise operational and safety requirements and functionality. There are severe requirements for a successful demonstration. First, the technology needs to work. Second, the demonstrations need to prove the financial and environmental benefits of the technology. Finally, the tests must also demonstrate the durability, reliability, and safety of the technology to end-users and regulators.

Pathways, Projects and Products

An organizational flow chart for Road 4 (Figure 5) illustrates the major DOT-wide pathways, projects and products, and their interrelationship to the other three Roads.

Federal Transit Administration (FTA)

The FTA is in the forefront of the research, development, and demonstration of fuel cell buses. Transit buses have been in the vanguard for demonstration of alternative fuels and hybrid electric systems for a variety of practical reasons. Weight and volume packaging constraints are less rigorous for buses than for light-duty vehicles. Buses can take longer to start and get running than is acceptable for personal automobiles. Transit buses are centrally fueled and stored at discrete locations, while the public expects personal vehicle fueling and storage options to be ubiquitous. Additionally, buses are driven and maintained by trained professionals, facilitating the safe introduction of this new fuel and propulsion system.

Perhaps most importantly, the success of transit buses in major population centers provides an opportunity to accustom the public to the safe operation of zero-emission hydrogen fuel cell vehicles. The operational and maintenance experience obtained through the introduction of fuel cell vehicle technologies in buses will significantly enhance successful applications in light-duty vehicles. Synergistically, the success of the FreedomCAR Partnership and Hydrogen Fuel Initiative will enable transit to take advantage of the economies of scale from the volume production of cars and light-duty trucks.

To accomplish this mission, FTA in partnership with key stakeholders, developed the Hydrogen and Fuel Cell Bus Initiative. This initiative is a broad-based, national effort to coordinate and consolidate the diverse efforts inherent in the development of hydrogen and fuel cell buses. This coordination will accelerate hydrogen's commercial viability and also encourage the successful commercialization of hydrogen fuel cells into other transportation applications. This initiative focuses on three vehicle technology development pathways: heavy-duty fuel cell bus, automotive-based fuel cell hybrid bus, and hydrogen internal combustion engine hybrid bus. Research, development, and demonstration efforts are underway for each of these efforts.

The FTA is also spearheading an effort to enhance international coordination and collaboration in fuel cell bus research, development and demonstration. The FTA conducted the First International Fuel Cell Bus Workshop in November 2003, in Long Beach, California, and the second workshop in Oporto, Portugal in November 2004. Representatives from fuel cell bus programs in Europe, China, Brazil, Canada, Japan, and Mexico participated. At the meeting, there was agreement on the benefits of greater information sharing, harmonization of data collection and evaluation, and enhanced coordination of future research, development and demonstration efforts. Participants also agreed on the benefits of establishing an International Fuel Cell Bus Working Group to foster greater coordination and collaboration. Additional workshops are being planned to build upon the groundwork of the first two workshops.

Federal Motor Carrier Safety Administration (FMCSA)

The FMCSA is not currently engaged in demonstration activities but will collaborate with other Federal partners to conduct demonstrations for hydrogen and fuel cell powered medium- and heavy-duty vehicles.

Maritime Administration (MARAD)

MARAD foresees slow-speed ferries and passenger water shuttles as being well-suited vehicles for the deployment of hydrogen and fuel cell technologies. The weight and volumetric flexibilities of these craft allow for ease of system design. The single point fueling characteristics require minimal infrastructure development. The vessels often operate in pristine environments, creating a premium need for low-emission technologies. Initial demonstrations will involve these types of vessels. Long-term efforts will seek to fully integrate hydrogen power and fuel cell technology across all marine craft platforms and in stationary port power applications.

Federal Aviation Administration (FAA)

The FAA is currently engaged in collaborative demonstration efforts with DoD and DOE's Solid-State Energy Conversion Alliance program to install, test, and evaluate high temperature stationary fuel cells. Current regulations prohibit the use of fuel cell power in National Airspace System (NAS) facilities. However, power that is purchased can be generated by fuel cells. Moreover, non-critical infrastructure and redundant back-up systems can be powered directly by fuel cells. This creates a pathway for validating the technology and demonstrating improved environmental results and energy security while providing greater power reliability to the NAS infrastructure. Once confidence in fuel cell power is established, FAA efforts will focus on fully deploying and integrating these technologies into NAS facilities.

Federal Railroad Administration (FRA)

The FRA has outlined a multi-year program beginning in FY07 to develop and demonstrate a fuel cell powered mainline locomotive. The rail system's fleet-centralized fueling infrastructure reduces infrastructure demands, and hydrogen and its feedstock commodities are already being handled by the rail industry. Demonstrations will target line-haul operations that operate in non-attainment areas or have diesel use restrictions where the need and ability to utilize new technologies are critical. The FRA demonstration projects will ultimately prove the viability and benefits of fuel cell locomotives to industry, and create an avenue for a long-term fleet turnover.

This work will build on current research being conducted by DoD for fuel cell locomotives.


Research, development, and demonstration activities will continue through the FY 2010-2015 timeframe. The operating characteristics of medium- and heavy-duty fleet vehicles result in a deployment schedule that will likely precede that for light-duty vehicles. Based on the success of the demonstrations with medium- and heavy-duty vehicles and the continued technology improvements resulting from industry and DOE research, initial heavy-duty deployment could occur prior to 2015.


DOT's activity is consistent with DOE's Hydrogen Road Map. DOT has primary responsibility for the development, demonstration, and deployment of medium- and heavy-duty hydrogen vehicles, while DOE's transportation-related hydrogen efforts focus on light-duty vehicle applications. Basic research in hydrogen storage and use as a fuel will integrate into DOT's development and demonstration activities. Lessons learned from this activity will be shared with DOE to help guide future research. Infrastructure built for DOT demonstrations can serve as a foundation for the expansion of infrastructure to the light-duty market. Ultimately, DOE's RDD&D program on light-duty vehicles will parallel DOT's activities on medium- and heavy-duty vehicles. DOT and DOE are actively coordinating and collaborating in data collection and evaluation efforts for fuel cell bus demonstrations already underway and those planned for both national and international markets.