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HYDROGEN GENERATOR - fuel cell ?

Discussion in 'Alternative Energy' started by badspell68, Jan 4, 2007.

  1. badspell68

    badspell68 New Member

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  2. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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  3. badspell68

    badspell68 New Member

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    But is this concept valid or is it bogus? Is it rooted in something real?
     
  4. dave

    Dave New Member

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  5. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    It takes more energy to split water to hydrogen and oxygen than you get by combining them (by burning the hydrogen) - it's just another perpetual motion type scam!.
     
  6. badspell68

    badspell68 New Member

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    Would adding hydrogen to your cars air intake improve milage? This is what they are pitching.
     
  7. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    Quite possibly, you can easily change a petrol engine to run on hydrogen, but it depends where you get the hydrogen from if it's worthwhile or not?.
     
  8. evandude

    evandude New Member

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    generating the hydrogen in the car and then burning it is nothing but a perpetual-motion scam, as nigel already stated.

    now, as for carrying along pre-generated hydrogen, it would cost more to buy the hydrogen than the amount of gasoline you would save. If you maybe generated the hydrogen slowly and for free by some renewable power (solar, wind, etc) via electrolysis then it might be somewhat more reasonable, however carrying around hydrogen in your car is dangerous (think hindenburg), and you would need to compress it a lot to carry any significant quantity (think several thousand PSI), thus raising your costs because compressors, storage tanks, solar panels, and all that are NOT going to be cheap, plus carring around a huge, heavy, fiber-wrapped hydrogen tank in your car is probably not going to help your mileage... (and probably be against all sorts of laws and safety regulations...) it's tough to say if you even COULD break even under any circumstances, but I think it's safe to say that you probably won't, at least not in a lifetime.
     
  9. Oznog

    Oznog Active Member

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    It won't work because your start out with mechanical shaft horsepower, use the alternator to convert it to electrical power with decent efficiency (85%), use it to make energy stored in the form of hydrogen+oxygen (30%-60%), then burn it in an engine to make shaft horsepower again (15%).

    The energy equations say there's no way to get more power this way. Now in theory if there was something really, really wrong with the way gas burns in an engine and a small amount of hydrogen could catalyze or somehow "fix" the process, you could benefit. However, no. The science of burning gas is VERY well understood and approaches its theoretical max thermal efficiency already. There's no pent-up energy on the virge of being released by a small amount of hydrogen, "fuel magnet", etc.

    If an electrolysis cell did work, you'd see it right away on vehicles. Scam's been around for at least 5 yrs, probably 20.

    I was really thrilled Mythbusters went public trying out these gadgets... nothing helped at all. Most decreased mpg, some substantially.

    They did make an engine run off a hydrogen tank. However, a big alternator can suck over 2 hp off the engine and even at ideal efficiency that converts only a trickle of tiny bubbles of gas into a huge volume of air going through an engine (thousands of liters per min).
     
  10. Hero999

    Hero999 Banned

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    There is a way to get energy from the hydrogen in water, it's called nuclear fusion.
     
  11. evandude

    evandude New Member

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    sweet, I'm gonna go build a reactor real quick and stick it in my car! I'll be back in an hour or so and let you all know how it goes! ;)
     
  12. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    Don't you need a DeLorean for that? :p
     
  13. Sceadwian

    Sceadwian Banned

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    45 dollars? You could probably build a unit capable of 10 times more hydrogen output using nothing but pencil lead (Graphite is a very good insolluble anode/cathode) and an old PC power supply. The key to hydrogen production is getting as much possible surface areas as you can for the anode/cathode's The more surface area and voltage applied the more hydrogen is produced. I've always thought of trying to use .5mm mechanical pencil leads which are pretty cheap and have a huge amount of surface area per volume as a home brew hydrogen generator. But I don't have anyplace to build something like that right now. (Small apartment already, I need me a man cave)
     
  14. akg

    akg New Member

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    May not be.. since the H has lower energy capacity then same amt of petrol . the key H is a clean fuel .
     
  15. Hero999

    Hero999 Banned

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    What's the maximum effiency of hydrogen production?

    If I used 1MJ to make a certain amount of hydrogen, how much energy will I get when I burn it? Obviously I know if it's 100% efficieny I'll get 1mJ back but I know that won't happen.
     
  16. Oznog

    Oznog Active Member

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    Maximum electrical efficiency varies a LOT. It requires less electrical energy as the temp is raised- it will actually absorb the thermal energy and cool the cell. But this is at VERY high temps. It is possible to get slightly more chemical energy out of H2 and O2 then you put in as electrical energy, however, the temps must be extremely high. This is not only very difficult to achieve but high-temp heat is not so cheap either.

    However, note hydrogen generation is not the real problem. The real problem is that burning in an internal combustion engine is like 15% efficient at getting torque (and alternator energy) back. A fuel cell is much more efficient, though there are still significant ineffiencies.
     
  17. mramos1

    mramos1 Active Member

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    Please send me the plans. I have a class project due tomorrow and I am out of gas so I can not get there. This way I can make it to class and then show the reactor as my final project..

    Car is silver if that helps. Not Delorean though..
     
    Last edited: Jan 7, 2007
  18. Marks256

    Marks256 New Member

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    I didn't read the whole post, and i don't mean to hijack the thread, but you can build a wood gas generator and run a combustion engine off of wood gas. You can use quite a bit for fuel, too; Peanut shells, wood(duh), thick grasses, ect.

    From what i gather, they are fairly simple to build, too.
     
  19. Sceadwian

    Sceadwian Banned

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    Just what we need on the road nowdays. Wood burning cars...
     
  20. Marks256

    Marks256 New Member

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    Yes, but it is pretty much free to people who have a lot of wood...
     
  21. Sceadwian

    Sceadwian Banned

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    I'm sorry, what, I couldn't see anything through the two inch solid wall of smog that will create =)
     

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