Keep on truckin'
A fuel cell-based auxiliary power unit currently being demonstrated by Freightliner LLC has future potential for the commercial trucking industry. Xantrex built the electrical management system on the Freightliner test truck,which was introduced earlier this year at the Society of Automotive Engineers 2003 World Congress in Detroit. The prototype liquid-fuelled auxiliary power unit (APU) incorporates fuel cell technology from Ballard Power Systems Inc. to generate up to 5kilowatts of 120-volt AC power. The APU is fuelled with a mixture of methanol and water, but further development will enable it to use ultra low-sulphur commercial diesel fuel.
The fuel cell creates power by extracting hydrogen from a methanol fuel source (eventually diesel) and then converts it into electricity. A DC-to-DC converter regulates the electricity created from the fuel cell so that the output power stays within the input parameters of the prototype Xantrex sine wave inverter/charger. And if the fuel cell can not supply enough DC power to the inverter, a 36-volt battery will supply it with supplemental power. Future fuel cell-powered systems could be set up to give truckers a choice about where they get their electrical power. The trucker of the future could plug into regular AC power when parked at a truckstop and use the fuel cell technology when at rest areas or loading docks. The inverter/charger technology complements both power sources.
