New Sell for Fuel Cell

BRUSSELS, Belgium - Chocolate, waffles and coffee; three tactile things tasted when Belgium is brought to mind - I know, I know. I am the ugly American. But face it: One doesn't routinely think of rocket science when Brussels is mentioned.

As it turns out, rocket science - or advanced technology - actually may follow coffee on the list of Belgian wonders in the not-too-distant future.

And with fuel cells, it's the future we're talking about, after all.

General Motors Corp. and its Adam Opel AG division show the latest joint effort in advanced vehicle technology here and outline their "alternative fuel" plan for the both near- and long-term.

GM and Opel say their brand-new prototype is the world's most advanced "operational" hydrogen-powered vehicle - and it may be hard to argue.

The technology is stowed away in a single Opel Zafira MPV - the 200-cell "stack" measures a mere 23.2x11x19.7 ins. (59x27x50 cm). The Zafira application builds on previous generations of GM fuel-cell vehicles and carries the moniker HydroGen1. It is a full 5-seat, A-class-sized compact van, propelled by a 75-hp (55kW) three-phase electric motor that is powered by a fuel cell that consumes hydrogen.

Unlike previous efforts with a fuel cell fed by hydrogen reformed onboard from methanol, the HydroGen1 is fueled by pure hydrogen - although currently there is next to no infrastructure to deliver hydrogen for public consumption. For that reason, Opel says that the HydroGen1 represents something of an ideal that will not be readily attained, so an interim step for market-ready fuel cell automotive power likely will have to be a vehicle with onboard fuel reformation - in order to take advantage of today's existing fuel-delivery infrastructure.

The crux of the program is the compactness of the fuel cell, which has been reduced in size by 30% compared to Opel's 1998 methanol-fueled version.

This enabled engineers to re-fit much of the technology with only minimal reduction in interior space - the rear passenger seat is raised 1.2 ins. (3 cm) and the rear load area is moved 3.9 ins. (10 cm) higher to make room for the hydrogen storage cylinder.

This small loss of interior volume is virtually imperceptible and can be easily overlooked when one takes into consideration how much the components have been downsized. Or that great strides have been made in operational aspects.

For example, repeated tests of the 200-cell, proton exchange membrane (PEM) series have the vehicle turning over and operating at an incredible -40degrees F (-40degrees C). Ambient cold is the enemy of fuel cells, because their process for converting hydrogen to electricity is not efficient until reaching an operating temperature something akin to room temperature.

Aside from the new ability to start relatively quickly in chilly temperatures, the fuel-cell stack of Hydro-Gen1 is improved as well. It develops 80 kW at constant load or 130 kW for brief peaks when aided by supplementary battery power.

As just about everyone now knows, in the fuel cell hydrogen and oxygen react electrochemically to produce electricity. In HydroGen1, this happens at 176degreesF (80degreesC), and the reaction generates between 125 and 200 volts of electrical energy. The only meaningful "emission" is water vapor.

The electrical direct current (DC) is converted into alternating current (AC) at 250 volts to 380 volts and fed to the 75-hp motor to drive the front wheels.

It can deliver constant torque of 185 lb.-ft. (251 Nm) from a standing start - the transmission no longer requires multiple gear ratios. Instead, a single-stage reduction gear is used. Total weight of the motor and transmission on HydroGen1 is 150 lbs. (68 kg), bringing the total vehicle weight to 3,472 lbs. (1,575 kg) - remarkably, only 330 lbs. (150 kg) heavier than a stock Zafira. It accelerates from 0 to 62 mph (100 km/h) in 16 seconds, reaching a top speed of 87 mph (140 km/h).

Currently, HydroGen1's powerplant is at about 50% efficiency, a figure better than even the most efficient direct injection (DI) diesel engines. And GM envisions a rate even higher, targeting 60% to 65% efficiency for the near- and longer-term.

The glass-fiber cryogenic tank on HydroGen1 stores hydrogen in liquid form at -423.4degreesF (-253degreesC) and has an 11 lb. (5 kg) liquid hydrogen capacity and a volume of approximately 19.8 gallons (75 L). GM says the specially made tank has the same insulating effect as a 29.5-ft. (9-m) thick layer of polystyrene. Storage also requires a vast assortment of valves and mounting hardware - as well as a heat exchanger - and weighs in at 209 lbs. (95 kg). The size and capacity of the complete storage system give HydroGen1 an operating range of 248.5 miles (400 km).

>From a business perspective, GM and Opel are placing heavy bets on >hydrogen - despite today's lack of infrastructure.

"This is the only energy carrier that will satisfy the need for a lasting reduction in carbon dioxide (CO2) emissions despite a steady increase in the number of motor vehicles on the road," says Dr. Erhard Shubert, co-director of GM's Global Alternative Propulsion Center (GAPC).

GM is backing up this singular commitment at its three worldwide GAPC locations - Mainz-Kastel, Germany; Rochester, NY; and Warren, MI. Within GAPC, more than 250 engineers and technicians, from fields such as physics and chemistry, work in close cooperation with more traditional automotive-related field engineers.

GM and Opel make clear that since an adequate infrastructure to support pure hydrogen vehicles is not in place, for now it embraces onboard gasoline reformation as its near-term focus. Jeff Kuhlman, GM-Advance Vehicle Technology, tells Ward's that GM made this decision based on the results of a full independent economic feasibility, environmental impact and hydrogen viability study; it was conducted by Ludwig Bolkow Systemtechnik GmbH.

Clearly, HydroGen1 represents another giant stride toward volume-production of fuel-cell automobiles. The "study vehicle" contains benchmark technology under the hood. Surrounded by auxiliaries such as a heat exchanger, cooling and process water circuits and the monolithic cathode/anode humidifiers, GM's fuel cell stack is positioned where an Opel 4-cyl., internal combustion (IC) engine would normally sit, taking up approximately the same volume.

Currently, GM and Opel have only one HydroGen1 prototype. And the automaker is taking a bit of a risk in its presentation: The single prototype car is slated to pace two marathons in the upcoming 2000 Summer Olympics. One must truly appreciate the confidence of the Olympic undertaking, considering the two "stalls" that occurred during test-runs (see sidebar). Rest assured, technicians will be on hand at all times.

Engineers at GM and Opel know they have a long way to go in bringing a fuel cell vehicle to market. Public perception, price and other technical intricacies - including evaporation losses and further storage advances - must be resolved for any kind of large-scale market feasibility to kick in. Still, with a solid plan and a flagship vehicle, the cross-Atlantic cooperative seems to be heading in the right direction for greener days ahead.

Now, I say "Belgium" and you think "hydrogen," right?