Um, this is NOT an environmentally friendly car, no matter what BMW claims:

[originalpckelly]

http://www.bmwworld.com/models/mini/hydrogen.htm

Yeah, for all those fans of hydrogen combustion, water vapor is greenhouse gas. I'm not joking. I know it sucks, but it's true.

[Infinite Hope]

1. That it is. n/t

[originalpckelly]

2. Now, if they could capture the water vapor...

that might not be a bad system. Maybe they could cool the vapor as it comes out, then store it in a tank. But of course, cooling takes energy.

http://en.wikipedia.org/wiki/Greenhouse_gas

^^^More info on this^^^

[tridim]

3. That does suck, I had no idea.

Is it equally as bad as CO2 and hydrocarbons?

[originalpckelly]

4. I don't know actually. I know it's a greenhouse gas from the way it re-radiates solar energy...

but I don't know how bad it is in comparison.

Heck, I don't know if climate scientists have even done studies on which is more effective at retransmitting solar energy.

[originalpckelly]

10. Check out post #9, water vapor is even worse than CO2!

[Harper_is_Bush]

5. uh....does water vapor slip up into the upper atmosphere and stay there for decades?

There's questions about the production of hydrogen utilizing significant energy, but the idea of critisizing the water vapor that such a vehicle produces is wrong-headed.

edit: I think you've fallen victim to the skeptics narrative. They've often cited water vapor in an effort to downplay C02. If you have a link explaining how vapor from a hydrogen car would contribute to global warming I will humbly apologize, but I don't think one exists.

[Cronus Protagonist]

6. You are correct

And water vapor condenses when it hits cooler air, causing nothing worse than rain, hail sleet or snow. If water vapor was a problem we'd have to do something about all these damn clouds :P

[originalpckelly]

9. Actually, no it isn't since a lot of the greenhouse effect comes from water vapor...

and we know that the water vapor in contrails has a significant effect on the environment.

Actually, here's a chart with the amount of CO2 and water vapor in the atmosphere:
http://en.wikipedia.org/wiki/Earth%27s_atmosphere#Composition

Here's an article about the greenhouse effect which states water vapor is an even worse greenhouse gas than CO2:
http://en.wikipedia.org/wiki/Greenhouse_effect#The_greenhouse_gases

[Harper_is_Bush]

11. You are not demonstrating your claim with these links.

You have been hoodwinked by the denial lobby.

Hey, how about this....the SUN is the real cause of global warming! It's not C02 at all, it's the SUN!

After all, all heat comes from the Sun. It bears sole responsibility...and since we can't do anything about the Sun we might as well just do nothing.

[originalpckelly]

14. Actually, I'm not denying Global Warming, I'm just saying that that particular...

avenue of solution is not exactly the greatest one to be pursuing.

[Harper_is_Bush]

32. Then you are denying all the science

that points to human prduction of C02 and methane as the main driver of the warming we're experiencing today.

Saying that water is a bigger contributor than c02 is a narrative of the denier/liar croud. I'm not saying you are one of that croud, but I think your knowledge on the subject has been negatively influenced by them.

[TankLV]

7. oh brother...kill all the cows too - they fart methane ya know...

Run!

Hide!

Spewing water and oxygen!

Oh my!...

I suggest there are FAR more important things to worry about, for sure...

This not even being in the top thousand...

[originalpckelly]

12. Actually, you're *kind of* wrong.

I refer you to post #9. Why waste time on an H2O combustion vehicle? And don't even get me started on the problems with wall-charged electrical cars (though those problems can be fixed.)

[Harper_is_Bush]

8. replace your lightbulbs with compact florescents, and tell your friends to do it too. nt

[Strelnikov_]

13. Any Water Vapor Generated Is Short Lived, Function Of Pressure-Temperature

Further, even if all the surface transportation in the world used H2, the quantity of water vapor produced would be insignificant compared to evapotranspiration and vapor off of water bodies.

The real problem is:

1) Most hydrogen produced today is from reforming of fossil fuels, CO2 is released in this process.

2) A viable 'Hydrogen Economy' is inefficient and will never be attained.

http://www.energybulletin.net/24093.html

[originalpckelly]

17. The diagram you posted is of a hydrogen fuel cell system...

which if it collects the water into a tank and not the air, I have no problem with.

The system I was talking about is hydrogen combustions, which is a nearly-standard internal combustion engine running off of hydrogen.

The system you posted is a much better route to be pursuing.

[eppur_se_muova]

28. Again, it doesn't matter. Most of Earth's atmosphere is SATURATED

with water vapor. Increasing the total amount of water does not change the equilibrium vapor pressure, as long as there is ANY liquid water present. (If you want to quibble, this is a sort of first-approximation argument -- the Earth is a dynamic system, and % water content varies from the eqiulibrium value, and from place to place and time to time. That makes Earth's atmosphere very hard to model.) And as pointed out earlier, the amount already present is enormous; "manmade" water would be a drop in the ocean.

It's true that water is a greenhouse gas. It's also true that water has ALWAYS been present in the atmosphere. Water vapor gets to be a complicating factor because more heat causes the eqiulibrium vapor pressure, hence the amount of water in the atmosphere, to increase. This would be equally true even in the total absence of any manmade water formation.

Also note that one way to generate H2 is by electrolysis of H2O. If that H2 is burned to regenerate H2O there is no net change even in the total amount of water, so it is doubly insignificant.

But I have heard the BMW H2 car is overpriced and inefficient.

[POAS]

15. That's it I'm going to stop

boiling water.

[Cobalt-60]

16. The vehicle consumes energy

The water vapor it emits into the air could be a nuisance if repeated by enough vehicles.
It is a smaller one that Co2 or other gases as most will ultimately condense out as rain.
Downtown could get pretty humid during the rush hour.
The pollution generated by the operation of this vehicle comes from the power plant that provides the energy to refine the Hydrogen.
If this is a Solar or Wind plant, we're ahead on pollution. If it's an old coal plant, we really haven't gained anything.

[originalpckelly]

18. Well, the problem with CO2 is not one vehicle...

it's all the vehicles we have doing that, all at the same time. It's the unnatural imbalance of CO2 which is bad, because there is a CO2 system which existed long before humanity.

It's the imbalance which causes the problem.

[piedmont]

19. Water vapor= EASY to scrub from exhaust...

CO2= IMPOSSIBLE to scrub.

I don't like hydrogen cars for other reasons, the main one being that
electricity-->hydrogen-->oxidation-->movement
is much less efficient than
electricity-->chemical energy in battery-->electricity-->movement

[originalpckelly]

21. Well, they didn't do that.

So, I called their BS.

I agree, but we have to really upgrade the transmission capacity in America for electric cars to work. We're already having problems with air conditioners, let alone cars.

I personally think it is the best because it allows even fossil fuels to be burned under their peak thermal efficiency, which is next to impossible in a car. So even if we just used fossil fuels on the other side, it would increase the efficiency.

I think we need to look at a Dyson "Ring" which is a series of satellites placed in space so that they never have to worry about clouds. We might be able to beam the energy back to Earth, because obviously some sort of system which requires people to travel back and forth from space would be prohibitively inefficient.

There is another type of system, which I'm thinking of, but can't remember it's name, which would also be a source of environmentally friendly "free" energy.

[physioex]

27. Hmm.....

Unlimited cheap energy could come from fusion but we are a long ways from getting there.

[Cobalt-60]

29. At U of I

we crushed beer cans with the magnetic "theta" pinch machine used for fusion research.
It was glorious.

[nosmokes]

20. the problem comes w/ the energy needed to produce and

condense the hydrogen, not in the water vapor that is the result of burning it. to try and say water is equal to or worse than carbon pollutants is delusional. and you don't hafta read what some dunderehead put on wikipedia, just take a look at your kid's or your friend's kid's basic elementary science text book. this is a no brainer. water = good/ carbon = bad.

[originalpckelly]

22. I'd say that's a little false. It's actually info from a book, if you took time to read it.

I know that it is a greenhouse gas from independent knowledge of Wiki, but it involves science which I don't really feel like explaining.

[nosmokes]

23. water vapor becomes water, right?

it's either a gas, liquid or a solid. simply because it reflects heat back into the atmosphere doesn't qualify it as a greenhouse gas in the same sense as co2 or methane or any of the other generally recognized greenhouse gasses. but i definitely agree w/you that hydrogen is not the way of the future, especially for autos. personally i think we need to stop dicking around with ETOH and really focus on bio-diesel, a fuel that can be produced and refined locally or regionally and that we already have a lot of the infrastructure in place. and

[originalpckelly]

24. Plants use up CO2 don't they?

The problem in both cases is related to an unnatural amount of either greenhouse gas.


We know from the days after 9/11, when airplanes weren't flying, that the lack of contrails increased the range in temperature from the hi to the low. In other words, low temperatures were a lot lower than the highs, when the planes weren't flying. That means during the days when planes fly, their contrails (which are condensed water vapor) act as a greenhouse gas.

I'm not a climate scientist, (but I play one on TV) no, but seriously, I watched this special called "Global Dimming" which presented this fact, as well as others stating that global warming would be even worse were it not for the sulfur in fuels. (The sulfur makes clouds more reflective, more energy goes back into space. It, however, also prevents water droplets from condensing into large enough drops to precipitate out the moisture. In is believed to have caused a drought in northern Africa in the late '70s early '80s.)

[Solon]

31. Now I know you are full of shit...

There is no way in hell that temperatures across a nation, much less the world, would be affected in a matter of DAYS due to planes being grounded. It would take months or years of planes being grounded before any effects are measurably felt.

[htuttle]

37. I don't think you quite get it

The problem we are having with greenhouse gases is that we are releasing carbon into the atmosphere that has been sequestered away underground for millions of years. When all that carbon used to be in our atmosphere, the earth was much hotter than it is today. By releasing it again, we are returning the atmosphere to the state it was in millions of years ago.

Carbon dioxide released by burning plant matter does NOT present as much of a problem, since the carbon that is sequestered in the plants, and released upon burning, was only 'fixed' in the plant while the plant is alive. That means that each growing season, they remove almost exactly the amount of carbon dioxide from the atmosphere as they will release when they burn. There is no net increase, as is the case when burning petroleum.

[GreenZoneLT]

25. Oh, this is ridiculous.

If water vapor is considered a major contributing factor to global warming, then human-based greenhouse emissions become insignificant. 99.999 percent of water vapor comes from non-human causes.

The problem, assuming the current climate change is being caused by human factors (it's possible we're just unlucky and the globe is rapidly warming up for some natural reason; it's happened before), is turning fossil liquids into gas. Hydrogen, if derived from fossil sources, is no better than gasoline; it's just a different storage medium along the way from underground hydrocarbon to aerial carbon. But it doesn't matter whether cars put out water vapor.

[physioex]

26. Right....

Cars are already producing water vapors. Gasoline is a hydrocarbon and when combined with oxygen for combustion, it produces water, CO2, and some other gases like CO NOx etc.... So my point is that we are already producing water vapor by driving our cars.

[htuttle]

38. Hell, we produce water vapor when we breathe

Hold your breath, everybody!

[Solon]

30. Look, hydrogen cars are inefficient, so not that economical for travel...

But calling WATER a greenhouse gas, when, in enough concentrations, it actually REFLECTS sunlight back INTO space, is ridiculous. CO2 is a greenhouse gas because it reflects infrared light that reflects off the SURFACE of the planet back down into the atmosphere, H2O does NOT act that way.

[Lydia Leftcoast]

33. I've been saying that for YEARS

Can you imagine the global environment turned into a steambath?

If the exhaust from cars released enough carbon to affect the global climate, what about STEAM from all the cars of the world.

Someone hasn't thought through all the implications. Besides, at this point, it requires more than the equvalent of a gallon of gas to make hydrogen fuel.

[MazeRat7]

34. No car is "environmentally friendly"... I think your missing the bigger picture here..

You are focusing on the emissions from the life time use of the vehicle... bad place to start and sure to return the smallest gains in GHG reduction.

While I own stock in several alternative energy companies that provide HFC's (hydrogen fuel cells) and gaseous hydrogen, I'll be the first to admit it is a poor choice where the environment is concerned because of the artifacts associated with the actual production of the hydrogen.

That being said, it is a great choice when it comes to reducing our dependency on oil since the primary source of hydrogen is natural gas. Yes the conversion of natural gas to hydrogen does release significant amounts of green house gases. In other words the CO2 is released by the production process not the consumption process.

Furthermore, a whole boat load of "green house gases" are released during the manufacturing process for the vehicle itself. Some estimates peg this number higher than what a gasoline engine would produce over the life of the vehicle (personally I don't think the numbers are that high). But the point remains that there is a huge foot print of green house gas associated with the production of any vehicle... even one that was 100% solar and farted air)

So bottom line, making statements about a vehicle being "environmentally friendly" is a very slippery slope. A reduced dependency on crude oil, improving efficiencies the mfg/recycling process, AND exploring alternative energy sources (not energy conversion and storage) should be top priority and of much more value than focusing on a specific vehicle and its emissions.

Given headway in those initiatives would guarantee improvements in our environment and economy.

MZr7

[htuttle]

35. Then you better stop taking hot showers! And boiling water!

Look at how much water vapor "escapes into the atmosphere" when you just make coffee!!

:sarcasm:


Um...Water vapor eventually turns into dew and rain, with any luck. You just plain don't know what you're talking about.

[ContraBass Black]

36. Of all the problems that Hydrogen cars have, water vapor release

Is not one of them.

[Richardo]

39. That's why it's so much warmer on a day with heavy overcast.

Ever notice that? :eyes:

[asthmaticeog]

40. CLOUDS are water vapor in the upper atmosphere!

We have to stop those clouds! Quick, let's make orgone accumulators!!!~!!11~~1!

[Susang]

41. Look out for the chemtrails!!!!

The clouds are hiding them, I just KNOW it! :scared: