Mike in Manila - Technology Notes

Sunday, April 23, 2006

A interesint alternative to Diesel Buesses

Reposted - from : http://www.greencarcongress.com/2005/12/fuelcell_bus_wo.html



Fuel-Cell Bus Workshop Focuses on Data Sharing, Commercial Viability and Infrastructure

Citaro_cutaway
DaimlerChrysler has the most fuel-cell buses in service: 36 Citaro units

As the Electric Drive Transportation Association Conference and Exposition was gearing up to open today in Vancouver’s Harborside Convention Center, the smaller—but no less important—3rd International Fuel-Cell Bus Workshop was winding down in the same venue.

About 65 industry leaders, government officials, and fuel-cell engineers had convened from around the world to review the state of the fuel cell bus today, and to work on three core issues: data sharing, commercial feasibility, and hydrogen infrastructure.

Hydrogen fuel-cell buses have begun to mature beyond simple demonstration projects, and are currently deployed on five continents, carrying more than ten thousand passengers per day along regular transit routes.

Worldwide, operational fuel cell buses include:

  • 33 DaimlerChrysler Citaro buses, three of each which have been distributed to Amsterdam, Barcelona, Hamburg, London, Luxembourg, Madrid, Perth (Australia), Porto (Portugal), Reykjavik (Iceland), Stockholm, and Stuttgart, as part of the CUTE (Clean Urban Transport for Europe) program. Three additional Citaro fuel cell buses that will be operated by China’s Ministry of Science and Technology (MoST) prior to and during the 2008 Olympics. (Earlier post.)

  • Fuel cell buses operated by three public transit agencies in California: Oakland’s AC Transit, the Santa Clara Transit Authority, and Sunline Transit in Palm Desert. (Earlier post.) The California Fuel Cell Partnership (CaFCP) has set a fuel cell bus target of two times conventional cost per bus with a six-year fuel cell stack life by 2010 to 2015.

  • A fuel cell bus operated by Berliner Verkehrsbetriebe in Berlin, which uses fueling stations built by energy companies Hydro, Linde, Aral, and TOTAL as part of Berlin’s Clean Energy Partnership project.

  • A New Flyer fuel cell hybrid bus in New Flyer’s hometown of Winnipeg, Manitoba, using a Hydrogenics fuel cell stack and Maxwell ultracapacitors, all integrated by ISE. (Earlier post.)

  • Eight Toyota/Hino fuel cell hybrid buses, which were used as shuttles during the 2005 Aichi World Exposition. (Earlier post.)

Hydrogenics_bus
The layout of the New Flyer fuel cell-ultracapacitor hybrid bus. Click to enlarge.

In addition, British Columbia’s state-owned BC Transit intends to put 20 hydrogen fuel-cell buses into service throughout the Resort Municipality of Whistler (RMOW) in time for the Vancouver 2010 Winter Olympics and Paralympics.

BC Transit does not view this as a demonstration project, but expects to run these buses well after the Olympics have ended. As Ron Harmer, Vice President of Technical Services for BC Transit remarked, “we keep our buses for twenty years here.”

One of the specifications in the preliminary RFP (Request For Proposals) is that all fuel cell buses be ready for retrofitting with commercially available conventional powertrains should the fuel cell systems prematurely fail. Five bus manufacturers and four hydrogen infrastructure suppliers responded to the first RFP in August. Funding for the project is due to be approved in March 2006, after which a second RFP will be issued. BC Transit will then select one bus and one fueling supplier by June 2006.

Whistler, a well-known ski resort north of Vancouver, has adopted aggressive sustainability issues that touch almost every aspect of community life, and is hosting all Nordic Olympic events in 2010.

Bch2hwymap
The BC Hydrogen Highway

BC Transit is also developing its own Whistler-to-Victoria Hydrogen Highway project, one that could conceivably lengthen to connect with California’s own Hydrogen Highway, creating a “BC to BC”—Baja California to British Columbia—hydrogen corridor.

One potential hydrogen fueling station would use waste hydrogen from a Vancouver sodium chlorate plant, which currently releases enough hydrogen into the atmosphere to fuel 20,000 fuel cell cars per year, according to BC Transit. (Earlier post.)

Conference participants explored the complex but crucial issue of data sharing. With limited funding available for fuel cell bus projects, co-operation is necessary to avoid duplication of research.

As many projects are at least partially funded by the public, project managers are somewhat obliged to be transparent with as much data as the public requires. However, many research partners are also competitors with one another, and “fast followers”—companies that have not participated in the research—could well leapfrog project partners if too much proprietary information is shared and made public.

The conference also focused heavily on hydrogen fueling infrastructure roadblocks. Most of today’s hydrogen fueling stations can handle no more than a few vehicles per day—a refueling station for more than ten 40-foot buses, in the words of one official, “is a huge undertaking” with today’s technology. The scope of demonstration projects is often limited by the reliability of refueling facilities as well as availability of fuel.

Hydrogen fueling sources range from wind or solar electrolysis to steam reformation to just plain trucking the hydrogen to the station, which must then fuel prototype vehicles, rather than production machinery. As one engineer explained, “Today we build a refueling station, and by refueling prototypes, we learn how each vehicle’s compressor works—but by then, it’s too late” to avoid performance problems.

Fuel purity, which directly affects fuel cell stack life, remains a problem, as it cannot be measured during the fueling process. Engineers at the conference appeared to be moving away from the oft-quoted hydrogen purity ideal of “six nines”—99.9999%—in favor of specific purity levels for each fuel contaminant.

Although most of today’s fuel cell buses simply transmit electrical current from the fuel cell system to the vehicle”s electric drive, almost all key vehicle and component manufacturers agree that the next generation of fuel cell buses will be fuel-cell hybrids, which add a high-voltage battery pack or capacitor bank to capture, store, and release energy during vehicle operation.

It can be argued that—for multiple reasons—fuel cell hybrid buses show greater promise for commercialization in the near future than do light-duty personal fuel cell cars and trucks.

The modern transit bus costs less than a tenth of its fuel cell counterpart. That’s a sobering difference, but not nearly as much as the commonly estimated 100-to-1 difference in cost between a standard automobile and a car powered by a fuel cell.

Public transit also uses centralized fueling with a known level of demand, which makes the fueling infrastructure easier to build, and refueling is carried out by trained personnel rather than the general public.

More design space is available on a full-size (40-foot) bus for hydrogen tanks, and fuel cell buses are more readily accepted in residential areas that are averse to the noise of conventional buses. Finally, public transit already moves people more efficiently than the private auto, and a high-profile fuel cell bus can serve as an effective rolling advertisement for hydrogen fuel cell technology.

—Jack Rosebro

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