|Projected hydrogen fuel cell system costs. Click to enlarge.|
The United States Council for Automotive Research (USCAR) recently published a whitepaper on the importance of continued research of hydrogen as a low-carbon transportation solution, in the context of the proposed cutting of hydrogen fuel cell vehicle research in the Department of Energy FY2010 budget. (Earlier post.) The whitepaper is available for download on the USCAR website.
A separate interim report by the National Research Council (NRC) assessing the strategy and structure of the Department of Energy’s FreedomCAR and Fuel Partnership, also published in July, concluded that although the Obama Administration’s focus on nearer-term vehicle technologies to reduce petroleum fuel consumption and greenhouse gas emissions is on the right track, there remains a need for continued investment in longer-term, higher-risk, higher-payoff vehicle technologies that could be “highly transformational ” with regard to those twin concerns. In addition to advanced batteries, such technologies include systems for hydrogen storage and hydrogen fuel cells, the review panel said. (Earlier post.)
USCAR was founded in 1992 with the goal of strengthening the technology base of the US auto industry through cooperative research and development. USCAR is governed by the three-member USCAR Council, whose membership includes the R&D vice presidents from GM, Ford and Chrysler.
Use of electricity as an environmentally-friendly transportation ‘fuel’ is dependent on progress in on board energy storage (batteries and ultracapacitors) and improved electrical generation and distribution infrastructure. Even with complete success in meeting the USABC long-term goals for battery energy capacity, electric vehicles cannot compete with hydrogen-fueled vehicles for general usage in terms of range and ‘refill’ time. Use of hydrogen as a transportation fuel as on-board storage for useful range and refill time is already available (if not optimal), for use in both highly-efficient, dedicated internal combustion engines or Fuel Cells Vehicles (FCVs).
Because profitable high-volume deployment of FCVs depends on significant progress in multiple technologies both on and off the vehicle, the USCAR OEMs have made deployment of hybrid, plug-in hybrid and various forms of electric vehicles a near term focus. Most of the core technologies (battery, electric-drive systems, system controls) of these ‘electrified’ products will flow directly to fuel cell vehicles. Similarly, the DOE support for ‘grid-connected’ vehicles will indirectly support the ultimate commercialization of FCVs.
Regardless of their individual strategies, the USCAR members are firm in their belief that hydrogen-FCVs will be an important powertrain option in our future of sustainable transportation. Given the long-term nature of this investment and the many uncertainties surrounding the rebuilding of our national energy infrastructure, it is not prudent to pick de facto winning technologies by ending all support for research and development of FCVs.—Hydrogen Research for Transportation: The USCAR Perspective
The whitepaper recaps some of the recent developments and successes in four areas fundamental to hydrogen fuel cell vehicles: fuel cells; hydrogen storage; hydrogen source pathways; and infrastructure.
While progress in fuel cells has tracked DOE and industry research projections for efficiency, cost reduction and durability improvement, there are still gaps to levels that would make fuel cell technology competitive with advanced combustion engines, USCAR notes.
|Capacities of different H2 storage systems. Click to enlarge.|
On the storage front, compressed hydrogen is adequate for many near and mid-term applications, though energy density and cost are still issues, USCAR says. Considerable progress has been made in the last 5 years to improve the storage density of hydrogen in vehicles; DOE and industry research has achieved roughly a doubling of stored capacity in advanced systems over the last 7 years.
The members recognize that continued research on material based storage systems is required in order to achieve performance and cost targets for the full range of U.S fleet model mix. The OEMs support the DOE approach to maintaining a research budget balanced across multiple material groups (metal hydrides, chemical hydrides and sorbents). A sustained effort utilizing DOE’s key technical resources such as the National Labs is required to ensure these new technologies reach commercial viability.
In terms of hydrogen production, the USCAR whitepaper says that while not the ultimate solution, steam methane reforming (SMR) can serve as the first of many future hydrogen production pathways.
Other pathways for producing hydrogen will exploit increasing availability of clean electricity, renewable feedstocks and carbon sequestration to drive down the carbon footprint of road transportation even as mass deployment of fuel cell vehicles begins. Just as for core fuel cell technologies, the research foundation for large-scale availability of clean hydrogen must be laid today, and DOE plays a central role in driving that research.
Given the longer-term nature of fuel cell vehicle commercializations, the OEMs do not consider a large, immediate investment in fueling infrastructure a high priority at this time, according to USCAR. However, some analyses suggest that the investment required to keep hydrogen availability well ahead of vehicle deployment so as to foster rapid adoption is modest.
A network of just 12,000 hydrogen stations would put hydrogen within two miles of 70% of the U.S. population (those living in the 100 largest metropolitan areas) and connect the major US metro areas with a hydrogen refueling station every 25 miles.
Continued government support of development over the next few years is very important to maintain stability of critical capabilities, maintain momentum and assure constant evolution of transportation fuel-cell technologies...developments relevant to stationary applications alone are far less likely to be applicable to vehicles.
Since it takes decades to “turn over” the light duty vehicle fleet, critical technologies must approach the point of commercialization in the next ten to fifteen years if they are to play a role in meeting our 2050 greenhouse gas reduction goals. DOE’s removal of support for transportation fuel-cell programs will dramatically diminish the US development of one of the truly zero-emission alternatives. Therefore, DOE should be encouraged to balance technology development priorities to include fuel cell vehicle technologies to assure that the current pace of development continues.