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Questions about a Hydrogen Economy; Scientific American

  1. Jun 5, 2004 #1

    Ivan Seeking

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    I wanted to point out a great article about our up and coming Hydrogen Economy. This article comes from the May 2004 issue of SciAm and it gives nice snapshot of the state-of-the-art.

    Not available for free AFAIK, here is an internet link and brief.

    http://www.sciamdigital.com/browse....B9BE5E6-2B35-221B-6F2461DEF9B52B9C&sc=I100322
     
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  3. Jun 5, 2004 #2
    Ivan Seeking said, "I wanted to point out a great article about our up and coming Hydrogen Economy."

    Isn't it a little misleading to call what this technology could make possible a "hydrogen economy"? That term seems to imply that hydrogen is an energy source in the same way that the petroleum we get out of the ground is. But that isn't true. We're going to have to make the hydrogen, and doing that requires more energy than the hydrogen provides once it's made!

    The advantage is that the energy can be produced in electric power plants and then easily distributed (in the form of electricity) through a conventional power grid to hydrogen production plants. But we're still going to need an energy source (coal?) to make the electricity that makes the hydrogen.

    So, where we're really headed (maybe), is toward an economy based more on coal than our economy is currently. Since we've got lots of coal in the US, that's good, but it's hardly a "hydrogen economy".
     
  4. Jun 5, 2004 #3

    Janitor

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    And of course coal is infamous for carbon dioxide (greenhouse) and sulfur (acid rain) and mercury (freshwater fish contamination) emissions.

    If it gets to where the average citizen of India and China lives the middle-class lifestyle of a typical Westerner, I shudder to think what our air and water may become.
     
  5. Jun 6, 2004 #4
    I remember hearing there's a decent sized initiative in the nuclear inductry to become one of the prime players in the production of hydrogen, which would be a lot better on the environment than coal would be.

    I link to the DoE's Nuclear Hydrogen Initiative: http://www.nuclear.gov/infosheets/hydrogenfactmarch2003.pdf
     
    Last edited: Jun 6, 2004
  6. Jun 6, 2004 #5

    Ivan Seeking

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    How this will finally pan out is anyone's guess. Yes, H2 is an energy carrier, not an energy source. That is H2 101, day 1. There is much, much more to this than you may realize. There are at least 2 dozen different approaches to H2 production that include biological approaches, such as by using H2 producing bacteria, and that involve many previously untapped resources. Coal does play a role, and frankly, the article is a little less positive than our friends at the National Hydrogen Association,

    http://www.hydrogenus.com/

    but a lot of good information is found in the SciAm report. Please see also an earlier discussion where I made my best arguments for all of this.

    https://www.physicsforums.com/showthread.php?t=4127
     
    Last edited: Jun 6, 2004
  7. Jun 6, 2004 #6

    Ivan Seeking

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  8. Jun 6, 2004 #7

    Ivan Seeking

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    I wanted to add that many good links are provided thoughout this thread.

    https://www.physicsforums.com/showthread.php?t=4127

    Please review this thread completely if you have any interest here. I did my best to provide much of the key information.

    I should also add that the SciAm article does significantly play down the energy cost of fossil fuels - well to tank - as I have tried to argue. I recognize this without conceding the argument. It would take some time to find out if we are really comparing apples to apples.
     
  9. Jun 6, 2004 #8
    Ivan Seeking,

    Thanks for the links. I read some, and I'll get to the others later. They're pretty encouraging, at least with respect to how close we are to having the technology.

    I can't believe I've gotten on the wrong side of this "argument" with you. I'm a fanatical believer in our need to do whatever is necessary to end our dependence on oil, both for environmental and political reasons. If hydrogen is the solution (or part of the solution) then we should push it hard. I just think the term "hydrogen economy" implies a little more than it really means.
     
  10. Jun 6, 2004 #9

    Ivan Seeking

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    Hey, no wrong side or right side here. :smile:

    I just wanted to make sure that you and everyone else realizes that more exists here than most people know. It is easy to be too quickly dismissed. For years I thought the 2nd law pretty much made this all a moot point but I now believe this not true.

    As for the term "Hydrogen Economy", this may be a glorification of the idea. I really don't know if any strict definitions of economics may apply, but the key concept is that H2 will act as a base, as the energy carrier for most other energy options. In this sense we would switch from a fossil fuel economy to an H2 economy. In the most hopeful sense, H2 might be viewed as the new currency for energy. Remember also that fossil fuels are no different than H2 in that fossil fuels are also energy carriers for solar energy. Same for hydropower and wind. So this can all get to be a matter of where we draw the line or how we choose to define things.
     
  11. Jun 7, 2004 #10

    russ_watters

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    Yeah, but there is of course a difference - an important one. For oil/coal the sun and earth already did 99% of the work to make it - with H2, we have to do all of the work to make it.
     
  12. Jun 7, 2004 #11
    russ_watters said, "For oil/coal the sun and earth already did 99% of the work to make it - with H2, we have to do all of the work to make it."

    Exactly!

    For all intents and purposes, petroleum and coal are energy sources. In the form in which hydrogen is available, (H2O) it's not an energy source. More energy will be used to turn it into an energy source than it will produce as an energy source. That's not much to base an economy on!
     
    Last edited: Jun 7, 2004
  13. Jun 7, 2004 #12

    Ivan Seeking

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    We don't do the work; nature does by solar powered chemical, biological, or even chemically powered mechanisms such as chemosynthesis. The same for fossil fuels.

    Look guys, no one argues that H2 must be produced. AFAWK, we have no ready made reserves for H2 available as we do fossil fuels. Anyone who feels that this argument needs to be made really needs to do a lot of reading. No serious advocate of H2 technologies would question this point.

    Is it anyone's position here that we should not pursue renewable technologies?
     
    Last edited: Jun 7, 2004
  14. Jun 7, 2004 #13

    Ivan Seeking

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    Fission and/or Fusion power can easily co-exist symbiotically with H2 technologies.
     
  15. Jun 7, 2004 #14

    russ_watters

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    In other words, burn more fossil fuels to make hydrogen? How does that help anything?
    Certainly not - I'm just not sure what hydrogen has to do with anything in this context. I think you probably understand the issue, but to the general public, they hear the politicians talking about a hydrogen economy and picture the hydogen materializing at the gas pump. Politicians (the people driving the issue) for the most part completely ignore the issue of manufacturing the hydrogen. And that's a dealbreaker for the whole idea. Its like talking about landing a man on the moon without first discussing how to get one in orbit around earth.

    Realistically if Bush or Kerry (both have picked up the issue) succeed in getting a million hydrogen powered cars on the road in 10 years and a hundred thousand hydrogen fueling stations, where is that hydrogen going to come from? Realistically. My bet is it'll come from hydrogen manufacturing plants that either take their coal-fired electricity straight from an already overloaded grid or make their own power using oil-fired gas turbine generators. Net result: more pollution, more dependancy on domestic coal and foreign oil, and a bigger energy crisis.
     
    Last edited: Jun 7, 2004
  16. Jun 7, 2004 #15

    Ivan Seeking

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    A review of the links given in the Hydrogen thread addresses the many methods explored for producing H2.

    Russ, I think your concerns are completely valid. You and I have already hashed this out pretty well in the thread linked and I realize that we disagree on questions of production. I will only say that this is a core issue being addressed on many fronts, and that many scientists feel that this is not a show stopper; but that much work is still needed.

    By no means is this a done deal. To "Go Hydrogen" could still mean many different things depending on how the technologies pan out.

    Finally, I make no bones about my motives here. I think we need many brains filled with thoughts of Hydrogen. Politically, economically, scientifically, and environmentally, H2 strikes me as our best hope to finally end our addiction to oil. The political motivation is now more obvious than ever. Bye bye OPEC!
     
  17. Jun 7, 2004 #16

    russ_watters

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    My opinion is the same as before as well: we need to focus on our power grid first, fixing a primary issue before a secondary (and tertiary?) one.
     
  18. Jun 8, 2004 #17

    Ivan Seeking

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    I should add also that to some extent the SciAM article referenced supports your position better than mine. On this point my response is that many key issues are addressed, but some of the important issues are not addressed.

    This is a very broad subject. This in fact is a key feature of H2: Decentralization of the energy supply.

    Unfortunately, this also demands that the range of solutions is very large. I don't know if I have even heard of all possible options for production. I see references occasionally that imply that even more can be found.
     
    Last edited: Jun 8, 2004
  19. Jun 8, 2004 #18

    Cliff_J

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    And I think this is the main stumbling block/selling point beyond the glassy eyed notion that H2 can work only with exclusive fuel cells produced by hand in the lab. The ICE is here to stay short-term, and the additional costs to equip/retrofit to FFVs that could handle H2 would be pretty insignificant long-term.

    After that, the notion of producing mass quantities of H2 from burning coal or natural gas is so illogical that it could only come from government members who are motivated by the individuals that can directly benefit from such a decision. At least Carnegie and Rockefeller were obvious targets to control, much less clear today. In the future we could call the Enron of H2 production from fossil fuels some sort of Hindenburg moniker, I can already hear great sound-bites and see the visuals....

    Maybe rebirth of the "flower-power" days will hit when the SUV goes the way of the muscle car and the VW van is replaced with a H2 compatible car. It'd be interesting to see which oil distribution companies make the journey or completely miss the target like the number of ice-box manufacturers and ice processing companies who embraced the refridgerator. (zero)

    Cliff

    P.S. Anyone have information on how much power eletrolysis requires to produce a given quantity of H2? Would it be as low as 10kW/1L?
     
  20. Jun 8, 2004 #19

    russ_watters

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    That would be a deal-breaker due to H2's efficiency as a storage medium when you recover the energy in an ICE vs fuel cells (30% vs 90%). I don't think there is any question that fuel cells can be mass produced - that they haven't is simply a matter of demand.
    The simple answer is 'the same amount of energy you get back when you burn the hydrogen.' Meaning, I don't think its really an important number - it just determines how big storage tanks need to be but doesn't affect generation costs. But in any case, its 285 kJ/mol. You can convert the units to whatever...
     
  21. Jun 8, 2004 #20
    This book:

    Fuel from Water
    Address:http://www.lindsaybks.com/bks/hydrogen/index.html

    Goes into extensive detail about that. The energy requirements vary considerably with the design of the electrolysis cells. One interesting thing he mentioned is that the voltage requirement tops off for any kind of cell at about two volts. It never takes more than that. The current depends on the materials of the electrodes, their distance from each other, the means used to isolate the electrodes, the size of the cells, and considerations like that. He does say that the smallest amount of energy needed to electrolyse one mole of water is 63.3 Wh at 25C (77F).
     
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