GM's Hydrogen Chimera

In the past few days Forbes, Business Week and George Will have all come out with stories on the problems at General Motors. Business Week focuses on the decline of Pontiac and Buick to argue that the company must manufacture fewer lines given the enormous costs of designing, marketing and making so many different models. Will connects GM’s troubles to its huge current and future employee health care outlays. The most interesting of the three pieces, however, is in Forbes, where writer Jonathan Fahey chronicles the company’s attempt to develop a car engine powered by hydrogen fuel-cells. GM has already spent more than a billion dollars on the creation of this car, and the company’s hopes for survival may depend on the success of this endeavor.

But the article makes clear: The mass-production of a hydrogen fuel-cell car may be a costly pipe dream. Moreover, it offers few, if any, net benefits to the environment.

Hydrogen fuel-cells are one of a number of fundamental automobile engine redesigns currently being developed. Coming to market much sooner is the hybrid-electric engine. The Toyota Prius, so popular among Hollywood celebrities, is an early version of the hybrid-electric automobile of the future. These cars, which use storage-cell batteries, may soon be the norm in California, and within a decade they will likely be standard throughout the country. Although storage cell batteries present environmental difficulties, they do provide energy more efficiently than internal combustion engines, and, consequently, hybrid-electric cars will reduce average automobile fuel consumption by approximately one-fourth. Toyota is the leader in their development.

GM, by contrast, has chosen to focus on hydrogen fuel cells. What are they? Hydrogen fuel cells are small cells linked up into panels made to capture the energy that’s generated when hydrogen and oxygen atoms join to create water molecules. Electrons freed from the hydrogen proton during the water molecule formation provide electricity that can be used to power a motor. Science fantasists and hype artists have always made this sound immensely useful and beneficial. After all, a hydrogen-fuel cell powered car would use no fossil fuels, and its exhaust would be pure, clean water.

But, as Fahey points out, there are many problems with this scenario. Here are but a few:

- Separating hydrogen requires energy. This would most likely have to come from use of fossil fuels. Hence, hydrogen fuel-cells might offer no benefit at all in terms of avoiding greenhouse gas emissions.
- To place the hydrogen fuel onboard, the hydrogen would have to be fused with a solid that hasn’t been created, chilled to super-low temperatures or compressed to an explosive, volatile density. And hydrogen is very dangerous when compressed. To any who might have forgotten, the Hindenburg contained hydrogen.
- Transporting hydrogen is a nightmare. How much energy would be needed to get tanks of hydrogen to re-fueling stations? And what would be the cost? Would the hydrogen fuel-cell idea be impractical merely for these reasons? No one knows for certain but consider that hydrogen takes up twenty-five times as much space proportionate to the ouput it would give to each car as gasoline does.

The article notes that the problem of storing hydrogen within a car is itself so difficult that GM gas been trying to figure out how it can make its prototype engines work when their hydrogen gas has been stored at a mere –196 degrees Celsius. (That’s – 311 degrees Fahrenheit.) The storage, it turns out, works better at hydrogen’s normal dew point, which is –252 degrees Celsius. But, unfortunately, it requires a huge amount of energy to keep anything that cool, and if the temperature bumps up the hydrogen turns into a gas and just slips away.

Getting some sense of how much of a chimera hydrogen fuel cells may be?



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