INL RESEARCH & DEVELOPMENT

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Arizona Public Service

Alternative Fuel Pilot Plant & HydrogenInternal Combustion Engine VehicleTesting

Alternative Fuel PilotPlant

The Arizona Public ServiceAlternative Fuel Pilot Plant isa model alternative fuelrefueling system, dispensinghydrogen, compressed naturalgas (CNG), and hydrogen/CNG blends (HCNG). Theplant is used daily to fuelvehicles operated in ArizonaPublic Service’s fleet.

Hydrogen Subsystem

The plant’s hydrogen systemconsists of production,compression, storage, anddispensing. The hydrogenproduced is suitable for use infuel cell-powered vehicles, forwhich the minimum hydrogenpurity goal is 99.999%.Hydrogen is produced usingan electrolysis process thatseparates water into hydrogenand oxygen.

At present, the hydrogen iscompressed and stored at amaximum operating workingpressure of 6,100 psi. Thefacility has over 17,000 scf ofhigh-pressure hydrogenstorage capacity and 9,000 scfof low-pressure hydrogenstorage capacity. The dis-

penser can fuel vehicles atpressures up to 5,000 psi.

Compressed NaturalGas Subsystem

In addition to producinghydrogen, the plant alsocompresses natural gas foruse as a motor fuel. CNGvehicles typically have 3,600-psi storage tanks. However, tofill a vehicle’s onboard tanks,storage pressures must behigher. The APS systemcompresses natural gas to

The INL manages the light-duty vehicle testing activities of the U.S. Department ofEnergy’s Advanced Vehicle Testing Activity (AVTA). As part of this activity, INL andAVTA teamed with Electric Transportation Applications and Arizona Public

Service (APS) to develop the Alternative Fuel Pilot Plant that produces and dispenses hydro-gen on site. The hydrogen is produced through electrolysis by operating a PEM fuel cell inreverse. The Pilot Plant also compresses natural gas on site and fuels internal combustionengine test vehicles that operate on 100% hydrogen, and blends of 15 to 50% hydrogen andcompressed natural gas.

pressures up to 5,000 psiusing a three-stage cascadepressure arrangement.

Hydrogen and Hydro-gen/CNG (HCNG)Internal CombustionEngine Vehicle Test-ing

The U.S. Department ofEnergy’s Advanced VehicleTesting Activity (AVTA) isevaluating hydrogen and

Alternative Fuel Pilot Plant and fuelingisland (above) and hydrogen low-pressure and two high-pressurestorage tanks with PEM electrolyzer(inset at left).

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INL RESEARCH & DEVELOPMENT

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HCNG internal combustionengine vehicles in closed-track and laboratory envi-ronments (baseline perfor-mance testing), as well as inreal-world applications –including fleet testing andaccelerated reliability testing(accumulating life-cyclevehicle mileage and opera-tional knowledge within 1 to1.5 years). Emissions testinghas also been conducted onseveral vehicles.

In addition to reducing theuse of petroleum, usinghydrogen and HCNG as afuel in internal combustionengine vehicles provides airemissions benefits. Testinghydrogen internal combus-tion engine vehicles alsosupports development of thehydrogen infrastructureneeded for fuel cell vehicles.

Management Contact

Tim Murphy208-526-0480Timothy.Murphy@inl.gov

Technical Contact

Jim Francfort208-526-6787James.Francfort@inl.gov

For more information

The AVTA, along with itstesting partners APS andElectric TransportationApplications, is operatingseveral 100% hydrogeninternal combustion enginevehicles – with Ford andMercedes Benz engines –as well as a dozen internalcombustion engine vehicles

Additional information about Arizona PublicService’s Alternative Fuel Pilot Plant andthese advanced alternate-fueled internalcombustion engine test vehicles can be foundat: http://avt.inel.gov/hydrogen.html

Facts about Arizona Public Service’s Alternative Fuel Pilot Plant• Location – Downtown Phoenix, Arizona• Objectives:

– Evaluate the safety and reliability of operating internal combustion engine (ICE)vehicles on hydrogen and blended HCNG fuels

– Quantify ICE hydrogen and HCNG vehicle costs, performance and emissions– Ascertain the safety issues for a hydrogen production operation in a commercial

setting– Develop a working model of a refueling system for ICE and fuel cell vehicles, and

evaluate the vehicle fueling infrastructure and vehicle-to-infrastructure interface• Hydrogen Generator – PEM fuel cell, 57 kW, 300 scfh hydrogen output• Hydrogen Compressor – Oil free, three stage, diaphragm compressor, 99.9997% purity• Hydrogen Dispenser – Dispenses hydrogen up to 5,000 psi• HCNG and CNG Dispenser – Dispenses HCNG and CNG up to 3,600 psi• CNG Boot Compressor – 300 scfm @ 60 psi• CNG Main Compressor – 350 scfm @ 4500 psi• High Pressure CNG Storage – 50,000 scf @ 4,000 psi• Fuel Dispenser – Pure hydrogen or CNG and HCNG blended fuels, with metering and

electronic billing interface

(including Daimler Chrysler,Ford and General Motorsvehicles) that operate on 15to 50% HCNG blends.Various fuel blends havealso been tested in a Ford F-150 to allow the comparisonof performance and emis-sions impacts.

INL is a U.S. Department ofEnergy national laboratory

operated by Battelle EnergyAlliance