Burning Hydrogen gas produces a comparable proportion of energy to gasoline, it produces a favorable byproduct (water), and produces no air pollution. Therefore it should solve all the problems of pollution caused by vehicles. Right?

Wrong. Don't forget the question, where do we get hydrogen gas? Aye, there's the rub. Hydrogen gas occurs naturally in the environment only in trace amounts, mostly due to the fact that the H2 molecule is an unstable molecule with high-energy bonds. In other words, it takes a relatively large amount of energy to form a hydrogen gas molecule. So how do you make high-energy molecules when you have hardly any to start with? By investing a lot of energy of course. Thus, the only available industrial-sized and economic means of producing hydrogen is through fossil-fuel burning plants. So there's your magical solution, create pollution to prevent pollution and burn oil to save oil. Brilliant.

The only merits of this plan I can think of is that it concentrates pollution and the emission of greenhouse gases that is currently unconcentrated.

For more detail on the production of hydrogen gas: http://www.eren.doe.gov/consumerinfo/refbriefs/a109.html

A common way to produce H2 is via reforming - Methane gas + steam reacted over a catalyst.

Then for H2 cars - the H2 is presumably in liquid form = electricity (lots) to liquefy (electricity typically being produced from fossil fuel plants)

H2 powered cars - a crazy pipe dream

You use fossil fuels to create gasoline, too. At least the cars that were using H2 would not be burning gasoline anymore. I think it sounds like a worthwhile project. Then again, I thought the corn oil idea sounded interesting...

I'd like to hear the efficiency of hydrogen fuel compared to gasoline fuel. If there's a significant increase in efficiency of one engine over the other, then that might change my perspective.

I suspect what's really going on is that Bush is making a cheap political maneuver to placate environmentalists. The best part of the plan is that it's a 15-year plan so he won't be answerable to the people when they find out it's a bunch of BS.

Hey, for the few of you who seem to be interested, I read something encouraging today in US News and World Report that addresses my issue with using hydrogen as the new automobile fuel. Basically, it seems a realistic possibility to catch CO2 emmisions at fossil fuel plants and literally burying the CO2 underground. Now, if THAT approach could prove to be cost-effective, it would turn H2 powered cars into a legitimate way to cut down on our greenhouse gas (CO2 being the one of main concern) emmissions. Here's a link to the article if you're interested: http://www.usnews.com/usnews/issue/030210/misc/10carbon.htm

Unfortunately, there was a smaller article in the margin reporting gloomy results of an experiment that provided the most hope for global-warming deniers, in my opinion....

The experiment is based on the fact that plants all respire CO2. In turn, it has been long established that plant growth rate is affected by the concentration of CO2 in the atmosphere. So basically, the hypothesis was that the more CO2 humans spewed into the atmosphere, the faster plants would recycle it, so eventually plant growth would counter our greenhouse gas production. Seems very logical, no? I thought so (although I didn't believe plants would respire enough to effectively counter human pollution)

Well, the experiment for the past seven years has consisted of pumping CO2 into a forest and studying how this affected growth rate and respiration rate of the trees there (Sound difficult? Probably, but I hear oil companies are providing hefty funding for this experiment). Well, as US News reported, at first everything went as expected, plant growth and respiration boomed when CO2 was pumped in. But now the growth rate has dropped to a mere 6% (if I remember the figure correctly) increase and is declining. Why? Because since CO2 ceased to become the limiting nutrient, other nutrients in the soil quickly became exhausted. An additional side effect was that detritus decay rates were also increased, which in turn resulted in higher production of greenhouse gases by microbes in the forest. This experiment still continues but the outcome is clear; Global warming is coming and is here to stay. Believe it people....Dr. William Schlesinger, the scientist heading the experiment now believes the best solution is to cut down on our consumption of fossil fuels. He has a very simple quote that sums up this position very effectively: "Rather than trying to gather up marbles that have spilled, let's not spill em in the first place." I agree.

The most obvious thing overlooked in these posts is the fact that in any hydrogen powered vehicle platinum must be used. When Bush made his announcement, platinum shot up $25.00/oz. Today it is around $670/oz. Because platinum is a rare (existing only in small amounts) metal its use in hydrogen vehicles will cause the price to skyrocket. Several thousands of dollars would be added to the price of the vehicle, putting it beyond the reach of most people.

I didn't overlook that, I simply didn't know it (although it sounds familiar now that you say it). It's an interesting point. I'll look into it and keep a look out for people addressing that point.

The fuel cells use platinum electrodes for conversion, much the same way platinum converts exhaust gases into water in a catalytic converter.

Fuel cells don't necessarily need platinum electrodes. They can use any inert conductor such as carbon or titanium (I think).

I thought that catalytic converters could be made of nickel catalysts too.

But the Hydrogen-Oxygen fuel cell could work since there's no corrosion of electrodes and you use water to produce water. Of course the problem is the cost of electrolysing water and liquifying the products.

Yeah, sounds like the hydrogen car's far from practical at this point. I found this grad student's paper provided a good overview of the technology: www.montgomerycollege.edu/Departments/StudentJournal/volume1/Forsythia_Igot.pdf

The bibliography led to solid sources of info as well.

Dragonflower,

Electrodes are conductors of electricity. The preferred metals in hi-tech operations are platinum, gold, palladium, silver, and some of the more exotic ones. Carbon doesn't conduct, and nickel is a very poor one.

Because of it efficiency in conducting and its durability platinum is nearly always the choice.

Check out this AIR CAR
http://www.edie.net/gf.cfm?L=left_frame.html&R=http://www.edie.net/news/Archive/6522.cfm supposed to be marketed in europe later this year.

Interesting technology applicable in urban areas. Might be useful in industrial applications such as warehousing and short transits of merchandise. Wouldn't go over too well in a city like Los Angeles, however. Too much time spent idling on the freeways.