Fuel cells start to look real
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Automakers are also focusing on using methanol to power fuel cells. In this scenario, methanol fuel-cell cars would bridge the gap in the decade or more it might take to build a hydrogen-distribution network. Skeptics decry the cost of installing the needed storage tankage, but advocates claim that, like the case of diesel fuel, only one in 10 pumps needs to be methanol-capable for the fuel distribution infrastructure to be viable.
Today, there is no central distribution infrastructure for methanol, neither in industry nor at the pumps. DaimlerChrysler estimates that it will cost about $400 million just to add methanol tanks to a third of the service stations in California, New York, and Massachusetts. It's estimated that each methanol installation would cost from $50,000-60,000 per station. "Who's going to pay?" is the question often heard. Others say the cost issue is overblown. Said one industry observer, "Even if gasoline is used for fuel cells, the gasoline formulation won't be the same we use today (it'll have less sulfur), so you'll still need to install a new gasoline tank, which costs from $20,000-30,000 for each service station. From that perspective, the cost issues surrounding methanol tank installation don't seem so dire."
In November, Methanex Corp., the world's largest producer and marketer of methanol, entered into a strategic alliance with Mitsubishi Corp. and Mitsui & Co. Ltd. to promote methanol for fuel-cell vehicle applications in Japan. The parties to the agreement will work with Japanese governmental and nongovernmental agencies to address any regulatory hurdles and encourage methanol-based fuel-cell vehicle demonstration programs. They will also work with the Japanese automotive industry to ensure a common fuel specification and ensure that methanol of a suitable quality and quantity will be available at retail stations. In addition, alliance members will cooperate with potential Japanese methanol retailers to work toward commercialization.
Today, methanol is produced on an industrial scale from natural gas, which is still available in fairly large quantities and often simply burned off as an uneconomic byproduct of oil production. Renewable sources such as biomass can also serve as feedstocks for hydrogen production.
Some fuel cells run directly on methanol rather than hydrogen. DaimlerChrysler, for example, is working on a direct-methanol PEM fuel cell, said Mohrdieck, which it "demonstrated this fall on a go-cart powered by a small 2- to 3-kW motor." Instead of gaseous hydrogen, it uses a methanol/water mix for fuel. At the anode, the methanol breaks down into hydrogen and carbon, while the water breaks into hydrogen and oxygen. The hydrogen is used in fuel-cell membrane. The rest forms carbon dioxide and bubbles away. Perfecting this technology, which is still at the lab stage, "is still a number of years away," he said.
Considerable research effort is being expended by automakers to reform methanol because it is sulfur-free (sulfur poisons fuel-cell stacks) and operates at a relatively moderate 300°C (570°F). But refining methanol into hydrogen is still a complex process involving many steps, each of which must take place at a particular temperature.
The methanol processor in DaimlerChrysler's new Commander 2 sport utility concept produces enough hydrogen to power the vehicle for about 200 km (125 mi) between fill-ups, said Mohrdieck. The SUV's range is limited by the small size of the methanol fuel tank - the result of carrying a bulky fuel reformer and two Mark 700 fuel-cell stacks. The fuel processor takes a half-hour to warm-up, which would be unacceptable to potential customers. The startup delay follows from the need to heat the steam the unit uses to break down methanol into hydrogen.
XCELLSiS is working on a next-generation fuel processor that uses a catalyst rather than steam to decompose methanol into hydrogen. Not only does the new system feature a rapid startup time and a fairly dynamic (load-following) operation, it is much smaller and weighs half as much as the reformer unit in the Commander 2.
Meanwhile, doubts are growing over the viability of methanol as a consumer product, at least in the U.S. Said one well-placed expert who wanted to remain anonymous, "My sense is that methanol is more and more becoming a losing proposition. DaimlerChrysler is pushing it, but GM, Toyota, Honda, and Nissan seem to be lukewarm about it." Beyond distribution difficulties, many consider methanol to be pretty noxious stuff - not only is it toxic if ingested, even splashing it on the skin can cause health problems. Current Japanese methanol-handling-method standards call for the use of gloves, for example. And because methanol dissolves in water, it poses a pollution threat to underground water supplies. Proponents, however, claim that methanol is no worse than gasoline.
