Suppose all cars were Hydrogen Powered:

[pinkpops]

Not likely anytime soon, and would probably require nukes to derive H2 from water -

But suppose all cars were hydrogen powered - What would the increase in water vapor do to the weather? How would it affect temperature and humidity in high traffic areas?

Water is pretty safe, but you can drown in it.

[Zenlitened]

1. You know, I've wondered the same thing. And what about slick roads?

The obligatory video of water dripping out the tail-pipe makes for a good story. But the truth is, that water is going to have to be captured.

[VTMechEngr]

20. Watch a car pull away from a light, it drips water too.

A fuel cell exhaust can be short to allow the vapor to stay a gas.

[ProgressiveConn]

2. Why couldn't the water be condensed? I don't understand why it would

give off water vapor. Why wouldn't the end result be a tank full of water instead of water vapor?

[pinkpops]

5. Interesting idea ...I wonder

how big a tank we would be talking about?

[ProgressiveConn]

8. Wonder what the ratio of gas fuel to water by product is.

Would it be feasible to put water recovery tanks at every fueling station? When you fill up you dump the water to be recycled at the same time?

[evlbstrd]

14. Water is very heavy. Ya have a big enough tank,

and efficiency might suffer.

[ProgressiveConn]

15. Gasoline is heavy too.

It might be possible. =)

[VTMechEngr]

19. But not as heavy....

[evlbstrd]

21. But in this scenario

you are adding water to an overflow tank, presumable generated from separating the atoms in a gas. The weight would increase.

Any actually scientists out there?

Separating atoms in gas in a moving vehicle.

Boom.
Can I get a Mr. Fusion?

[punpirate]

3. Not greatly different...

... remember that a significant portion (by weight) of current auto exhaust is also H20.

And, if the fuel use were in fuel cells, fuel use in traffic jams would probably go down considerably, since they operate more or less on-demand.

But, traffic smash-ups would get a lot more interesting....

[Zenlitened]

6. Ah, that makes sense. There already IS a lot of water vapor...

... being released. Good point.

The smash-ups, though... yikes. :scared: People don't know how to drive on DRY roads. Imagine a perpetual rainy day on the highways!

[VTMechEngr]

18. It will still be in vapor form.

Fuel cells still run hot and the water produced is still in a gas form. No change from now.

[Mrs_Beastman]

4. Thank you!

anything in excess will throw us off balance. I'm glad I'm not the only one:tinfoilhat:

Also,diesel engines can be modified to run off corn oil.....why hasn't anyone done this?

[dflprincess]

7. There are people modiying diesel engines

I've heard a couple things about it lately. At least one outfit uses the cooking oil restaurants throw out. The restaurants are glad to let him take the stuff because they have to pay to dispose of their used oil.

[Mrs_Beastman]

10. There is hope. Thanks

[jdj]

17. go to greasecar.com ... people are doing it all over the place.

of course the corps don't want the word to get out that if you have a diesel you can spend about $1000 bucks and get your engine converted so all it takes it just a touch of real diesel to start it, and then you can get the rest of your fuel for free at chinese restaurants.

[Mrs_Beastman]

23. Thanks

Added to bookmarks..Mr B is thinking of getting a VW to restore, so it would behoove him to save money on gas since he will be spending his money on parts

[B Calm]

9. If the pukes hadn't stolen the election from Al Gore, we would

probably all be driving solar powered flying cars by now. Pukes don't have an energy plan, other than endless war and drilling up Alaska..

[Az]

11. The water emission is about the same as combustion engines

So no major difference.

[retnavyliberal]

12. The Theory is....

Fill up with a tank of water. Electrolysis (running electricity through the water) separates the H and O2. H is burned and makes the same amount of water you started with. The problem is you need a lot of energy to separate the water and where do you get that from. There is no perpetual machine.

http://www.hydrogennow.org/Facts/FAQs.htm

[northzax]

26. well there's the catch, isn't it?

you need to put more energy into splitting the water molecule than you get putting it back together...

[Hugin]

27. People often forget the Latent Heat Energy in water.

No, it's not a perpetual motion solution. But, there's
more energy there than you would suspect.

Keep in mind Electrolysis is an endothermic reaction
and recombining the molecules is an exothermic reaction.

[retnavyliberal]

31. Very true,...

and believe me, I am not a chemical engineer. However, it seems that no matter how you slice it, there is going to be a need for some external power. There are 3 needs for power that I can think of. Separation, Ignition, and the Power used for motion. I do not think that the "burning" of the hydrogen will be able to provide all three. There will also be energy loss from friction and the like. Can the extra power be stored in batteries and used to supplement as needed? Can Hydrogen and Fuel Cells be combined (which is my personal favorite idea). It would be interesting to see.

[Hugin]

32. Answer...

Sorry it took so long for me to get
back to ya.

"Can the extra power be stored in batteries and used to supplement as needed?"

Yes, used in the On Demand manner Hydrogen is at least as
efficient as other forms of internal combustion. Like 40
to 60%...

My favorite energy storage method is the flywheel.

[aint_no_life_nowhere]

13. Does anyone have links to stories about oil companies buying up patents?

I've read many posts about this subject, including ones on Daily Kos about companies like Exxon (enjoying record profits by the way) buying up and sitting on alternative energy technology. However I never see specific links to either webpages or references to specific texts. Does anyone know any sources of hard information on specific patents that are now being deep frozen and what that technology might be (assuming this is the case)?

[VTMechEngr]

16. Remember that combustion of gasoline produces water and CO2

No change.

[hunter]

22. H2 fuel cell cars actually exhaust less water than gasoline fueled cars.

But I haven't seen a practical hydrogen fueled car yet, and I dont expect to. (These are the pretty things they dangle in front of you as they are stealing your wallet.)

[ProfessorGAC]

24. Sorry, Hunter, You're Math Is Wrong

An H2 car would have to generate more water because 100% of the hydrogen is converted to water, rather than 17% by mass of gasoline converted to water.

Add to that the fact that the heat of combustion for an equal mass of H2 is lower than that for gasoline, you now have to burn more of it than gasoline for the same distance traveled. So, you have more hydrogen burning, and it ALL converts to water. For gas, you burn a lower mass and only 17% of that mass converts to water.

Using octane as the reference: Molecular Weight = 114. Let's say we have 114 grams of it. 18 of that is hydrogen, 96 of it is carbon. If it burns completely, 96 grams of carbon converts to CO2 so it generates 352 grams of CO2. The 18 grams of hydrogen becomes 162 grams of water. The burn will generate about 570 kJoules/mole.

For hydrogen, the heat of combustion is only about 91% of octane. So, we need to burn 125 grams to get the same energy. This will generate 1,125 grams of water.

Now, i'm all for developing a hydrogen powered engine, since water is not a pollutant, and it's actually easier to assure complete combustion with H2 than it is with hydrocarbons. (Hence gasoline engines emit a certain amount of carbon MONoxide and unburned hydrocarbon, albeit in ppm ranges.) But, a hydrogen motor will always generate more water than a gas engine.
The Professor

[hunter]

25. This is so cool! I got a reply from the Professor!

:bounce:

Let me now exit my caffeine induced coding fugue (I've been busy propping up someone else's ancient vbasic code that has been slowly devolving over the years, and ughhh, if last night's posts are any evidence, I probably better take a break now, before I make things much worse for myself...)

Nevertheless, I will now wave my arms and explain how we are comparing apples to oranges, and then maybe I will go crawl back under my rock until I can see straight again.

This is not a discussion of two identical cars, one with a gasoline powered internal combustion engine, and one with a hydrogen powered internal combustion engine. In fact, the notion of using hydrogen in a conventional automotive drive train seems rather silly to me unless we find some magical way of storing hydrogen.

I stated specifically I was talking about hydrogen fuel cell powered cars vs. conventional gasoline powered cars. It is widely claimed that the efficiency of these hydrogen fuel cell electric cars is much greater than that of gasoline powered cars, let's say something like 60% compared to 15%... in which case you still win, but not by such a wide margin as you describe.

And then I can wave my arms again, and compare some random gasoline powered Suburban Assault Vehicle to a lightweight hydrogen fuel cell powered street hopper, and the difference goes away entirely.

In any case, I can't imagine how the water from hydrogen powered cars could be any worse than the carbon dioxide and pollutants spewing forth from gasoline powered cars.

Still, I stand humbled. Thanks!

[hunter]

30. Running the numbers...

As a fuel, one gram of hydrogen is roughly equivalent to 2.5 to 3.0 grams of gasoline.

Taking your numbers for gasoline, 114 grams of gasoline will yield 162 grams of water.

Replacing 114 grams of gasoline with 45 grams of H₂ the yield will be 405 grams of water.

If the fuel cell powered car has a little more than 2 to 2.5 times the efficiency of the gasoline powered car (which is not unreasonable) it will produce the same amount of water.

[Touchdown]

28. Nukes will (eventually) not be required.

...neither will fossil fuel burning either.

Plants separate H from O2 every day. They get their nutrients from H. Scientists are studying how leaves do it, and once we can artifically replicate how it's done, then the true hydrogen revolution can begin. Some are saying, however, thet research is going to take 20 years or more to figure it out.

Imagine a power plant that looks like a tree. Hmmmm.

Regarding the rise in water levels, I'm sure that would increase the humidity levels slightly in some congested cities. But, look at the Amazon forest...it's one big Hydrogen generating complex, and it's exhaust is the oxygen that we all need...AND it's being clearcutted day by day. If Los Angeles can take up some of the slack, then all the better.:shrug:

[HamdenRice]

29. Two Words: ....

Blade Runner