Principal Investigator: S. Unnasch
Arcadis Geraghty and Miller, Inc.
August 1999

ARB Contract No. 95-313 (Full Report)

ABSTRACT

Fuel cells directly convert the chemical energy from the oxidation of hydrogen into electrical energy. With this process, energy conversion efficiencies on the order of 80 percent are theoretically possible. In comparison the theoretical energy conversion efficiency for a fuel burning piston engine-generator is generally limited to less than 50 percent while somewhat greater efficiencies are possible with combined cycle systems. The use of fuel cells offers the added potential of a mobile power source with low emission characteristics.

Over the past 30 years, certain types of fuel cells were developed and used extensively for the United States (U.S.) space program. Unfortunately, fuel cells suitable for space applications are poor candidates for vehicle use, because the need to generate and supply hydrogen gas produces fuel handling, storage and safety problems.

1.1 PROGRESS IN FUEL CELLS

Worldwide, numerous programs are underway to adapt fuel cell technology to the constraints of light-duty and heavy-duty vehicle operation. In the U.S., the Department of Energy's Partnership for a New Generation Vehicle (pNGV) recently announced breakthroughs towards its goal "to develop technology that leads to a passenger automobile with 80 miles per gallon fuel economy." The DOE asserts that "the new technology converts the gasoline or alternative fuel into the hydrogen needed for the fuel cell to produce electricity." The DOE also states that "the technology is clean and efficient with emission levels much lower than California's Ultra-Low-Emission Vehicles Standard."

Considerable interest also exists within the automobile industry. For example, Daimler Benz has boldly announced that they will have 100,000 fuel cell vehicles on the road by 2005. They have formed a joint venture with Ballard Power Systems and Ford to make this happen. Daimler Benz has also demonstrated a zero-emission, stored-hydrogen, fuel cell vehicle, called NECAR and more recently has shown their new "A" class urban vehicle (NECAR 3) equipped with a methanol reformer fuel cell system to help address range and refueling infrastructure issues.

1.2 EMISSON STANDARDS

The South Coast Air Quality Management District (SCAQMD) has implemented a clean fuels program and also has specific inventory reduction goals. Fuel cell powered vehicles can playa role in providing further emission reductions particularly in crowded urban areas where particulate emissions are a more important issue and regions where attaining ozone standards requires controlling NOx and hydrocarbon emissions.

Fuel cell vehicles can also play an important role in helping automobile manufacturers comply with the Low Emission Vehicles (LEV) rule that was adopted by the California Air Resources Board (ARB) in 1990. The rule is designed to further the development of low emission technologies. The LEV rule calls for fleet average emission limits and for a percentage of new vehicles in 2003 to be zero-emission vehicles (ZEVs). A ZEV is defined as a vehicle that produces no emissions during any operating condition throughout its life. Battery-powered electric vehicles (EVs) and dedicated hydrogen fuel cell vehicles are considered to be true ZEVs. Fuel-ceIl powered vehicles with fuel reformers may qualify as ZEV equivalents.

Table 1-1 shows the LEV exhaust standards applicable to all Transitional Low-Emission Vehicles (TLEVs), Low-Emission Vehicles (LEVs), Ultra-Low-Emission Vehicles (ULEVs) and Super-Ultra-Low-Emission Vehicles (SULEVs).

The SULEV category would have two separate useful life mileages: 120,000 miles, and an optional 150,000-mile useful life. The 150,000-mile certification would be required for SULEV-certified vehicles to qualify for partial ZEV credits if they met certain criteria.

The addition of the SULEV standard will impact the implementation rates for the reduction of the fleet average NMOG requirements as shown in Table 1-2. Only the fleet average would be a regulatory requirement; manufacturers could choose their own implementation schedule as long as the fleet average requirement is met each year.

• List of Illustrations - Section 3 (PDF - 4,247K)
• Section 4 - Section 8 (PDF - 5,274K)
• Appendix A - Attachment D (PDF - 2,520K)

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