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Hydrogen energy, a hoax

  1. Jun 3, 2005 #1
    ok im not bright, but hydrogen can only work if an outside energy system supplies more energy then is actually harnessed by its combustion.

    in a simple closed system, if water is converted into hydrogen then back into water. it is a scientific fact the system could only loose energy. even using every ounce of hydrogen energy created, that energy would never be enough to even sustain the loop... let alone power millions and millions of cars. if you wished to extract the equivalent of 1 single battery, more then 1 battery's worth of energy would need to be expended in order to create the hydrogen equivalent. the only reason hydrogen is considered at all is because, once you have hydrogen sensless masses think wow this is great no harmful by products. and others even simpler believe they can just keep converting it back and forth as though man was able to create a perfect pendulum.

    It holds many possibilities though, if it can be harnessed through natural sources like swamps. or using massively efficient factories that can convert energy from other, less user friendly sources. it is quite possible that hydrogen could be a very effective form of holding and transporting raw energy... however to create hydrogen, would the companies and government let us into the secret that they had to use up, a greater equivalent of another form of energy?

    i know my grammar and spelling is weak plz post any problems...
     
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  3. Jun 3, 2005 #2

    Q_Goest

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    Hydrogen is not an energy source, it is a carrier of energy analogous to the electric power lines that criss cross the world. Hydrogen, as viewed by the "hydrogen economy" of the future, is merely a way of transporting energy from one place to another. So you're correct, it is NOT an enery source.

    One issue which DOES come up as an aside from it being a transporter of energy, is the fact that if you take petroleum and convert it to gasoline for burning in an internal combustion engine, the amount of usable energy obtained is/potentially is less than that obtained from converting the petroleum to hydrogen and then using that hydrogen in a fuel cell. This is because the fuel cell is relativly efficient (~50%) compared to a car engine which can be less than half that efficient.
     
  4. Jun 3, 2005 #3
    Actually, many engines are around 10-15% efficient, well less than half that.
     
  5. Jun 3, 2005 #4
    while refining petroleum into gas involves burning of impurities. i would believe adding a complete energy conversion to result in atleast a form of additional loss.

    a quick question, if current engines use energy at 15% efficiency. what likely energy conversion loss should we expect? (from petroleum into hydrogen)
     
    Last edited: Jun 3, 2005
  6. Jun 3, 2005 #5

    Danger

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    Hydrogen can be used in so many ways that it's impossible to give a definitive answer to that. If you're thinking of fuel cells for an electric vehicle, the technology is advancing too rapidly to make a definite statement about what the 'state of the art' will be by the time they become commonplace. The motor and control devices will account for a lot of the efficiency, and they're getting better all of the time too.
    Hydrogen, however, can also be burned in a normal (modified) engine the same way that propane and natural gas are now, but the efficiency would be higher simply because 100% of hydrogen is flammable instead of it carrying 'junk' with it into the cylinders. (Some kind of piston-ring lubricant might be needed, but that could be introduced from the oiling system.) It can be used in a turbine engine as well, or a Wankel, or a K-cycle. If you really wanted to, you could even convert it back into water and use it in a steam engine. In any event, other than the steam one, it's going to be better than hydrocarbon fuels in a reciprocating engine.
     
  7. Jun 3, 2005 #6

    krab

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    Let's not get carried away. My car gets 25% efficiency. I just calculated it from my fuel consumption rate.
     
  8. Jun 3, 2005 #7
    How would you do that?
     
  9. Jun 3, 2005 #8

    Ivan Seeking

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    What do you drive; a diesel powered auto?
     
  10. Jun 3, 2005 #9

    Ivan Seeking

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    All about Hydrogen as an energy carrier See also the summary of all links to date near the end of the thread.
     
  11. Jun 3, 2005 #10

    Pengwuino

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    I think a lot of people are completely uninformed like this guy is about the "hydrogen economy". Most of us realize that yes, it is an energy transportation method but a lot of people think that we are somehow create energy from hydrogen. Are some 'up to no good' people proliferating this idea or what?
     
  12. Jun 3, 2005 #11

    Ivan Seeking

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    No, I think this is a simple misunderstanding caused by a lack of exposure.
     
  13. Jun 3, 2005 #12

    krab

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    I drive a small car (MR2); it needs to put out 20 hp to go 60mph (from car road test results). That's 11,000 ft-lb/s / 88 ft/s = 125 lb or 560 newtons average force. Gasoline has 30.4 megajoules of energy per liter. Energy divided by force is distance, so expressing energy in liters of gasoline instead of joules, we get 55 km/l. I know that driving at a steady 60 mph, I get better than 14 km/l (that's 33 mpg in US gallons; this I know extremely well, since I have a habit of calculating mpg at EVERY fillup, and know what conditions get me what mpg.) 14/55= 25% efficiency.
     
  14. Jun 3, 2005 #13

    pervect

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    I recall one speaker on CSPAN Book-TV talking about global warming. He was very emphatic that what made sense was to get rid of coal, first. The next step was increased production and usage of hybrid vehicles. Hydrogen fueled cars would be a distant third, if it made sense at all.

    This is of course in sharp contrast to the current USA administration policy, which puts the "hydrogen economy" first. Anyone who takes even a brief glimpse at the current administration can judge for themselves how much the current adminsitration is driven by concern for the environment, and how much they are driven by political contributions from big businesses such as coal and power companies. A few hints:

    The Enron affair, where our current president didn't feel that it was important to hear the conerns of the then California governor, as he was adaquately advised by his staff. Another broad hint comes from the dismisal of the EPA lawsuits against the power companies.
     
  15. Jun 3, 2005 #14

    Pengwuino

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    ah think so? I declare conspiracy! Its a ploy by the same people who filmed the faking of the moon landing out in the mojave desert! mmmm desert *homer drool*

    I wonder why this stuff doesnt get much coverage though... dare i say science doesnt get a few hours on cnn???? lol. Anyone know what the status is on that new power plant permit that the government issued?
     
  16. Jun 3, 2005 #15

    Pengwuino

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    Are you crazy? This administration busted Enron and Davis was a f'n criminal! He OPENLY took a bribe from... ah crap anyone know that company... it wasnt publicized much. He cooked the books and forced our state into this "rotating power outage" bull. I wouldnt have listened to that crook if my life depended on it. He was such a crook that we actually voted an austrian actor from hollywood to take his place :confused: :confused: :confused:

    And the guy must be obtuse or something. Hybrid still uses gasoline and hydrogen, if created with the sources the administration wants, would be one of the cleanest means of energy use available.
     
  17. Jun 3, 2005 #16

    Danger

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    I have first-hand experience with the fact that some people with no scientific knowledge whatsoever, particularly those who are somewhat less than bright, think of fusion (especially bombs) when they hear the word 'hydrogen'. A lot of them don't even know that it burns. Those same people are scared of helium because they think that's what the Hindenburg was full of!
     
  18. Jun 4, 2005 #17

    pervect

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    Probably. So what?
    Well, I hope you're being sarcastic - real Republicans talk pretty much like you do above, except that they generally don't ever admit to being confused.

    Riiightt - Let's burn more coal in power plants, or coal gassification plants, (without any of those stinking EPA pollution controls, please!) to create hydrogen!

    Now, we could make cars as fuel efficient as possible (hybrids) so they don't burn much fuel in the first place, but where's the money in that?
     
  19. Jun 4, 2005 #18
    Krab, you are a smart guy to know how to calculate this, but honestly that is not the right approach. You admit your car gets very good gas mileage, yet you think 10 to 15% efficiency is not reasonable? Please. Most people I know do mainly city driving, and none of them drive through town, approach a stopsign, or park a car at a steady 60 mph. Driving highway speeds generally does increase efficiency, so I will have to stand by my original estimate.
     
  20. Jun 4, 2005 #19
    yes ive gathered that hydrogen burning is efficient once you have the hydrogen. though my question, what additional energy loss should we expect creating hydrogen?
     
  21. Jun 4, 2005 #20

    Danger

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    To me, it seems that a ground-up approach would be the most efficient method. Build your hydrogen production facility on the ocean shore (or an island) to forego having to transport the water, and use a wave-power generator for processing.

    As a side note, such facilities in 3rd World countries could also incorporate desalination equipment to provide fresh water where there's a shortage.
     
    Last edited: Jun 4, 2005
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