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Transportation Earth Power Technology

Can Urine Rescue Hydrogen-Powered Cars? 313

thecarchik writes with this interesting excerpt: "It takes a lot of energy to split hydrogen out from the other atoms to which it binds, either in natural gas or water. Which means energy analysts are skeptical about the overall energy balance of cars fueled by hydrogen. Ohio University researcher Geraldine Botte has come up with a nickel-based electrode to oxidize (NH2)2CO, otherwise known as urea, the major component of animal urine. Because urea's four hydrogen atoms are less tightly bound to nitrogen than the hydrogen bound to oxygen in water molecules, it takes less energy to break them apart."
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Can Urine Rescue Hydrogen-Powered Cars?

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  • Uh, the chemistry (Score:1, Interesting)

    by Anonymous Coward on Wednesday July 08, 2009 @02:49PM (#28626431)

    I did chemistry nine years ago, however with regards to this sentence: "Because urea's four hydrogen atoms are less tightly bound to nitrogen than the hydrogen bound to oxygen in water molecules, it takes less energy to break them apart."

    Isn't it so that the energy of activation is rather irrelevant once you have a reaction going, because whatever energy is added to push them over the energy hurdle is released once the molecule separates? The only effect of a catalyst, if I remember correctly, is to reduce the energy hurdle, but it does not increase the amount of energy released (except perhaps through thermal efficiency).

  • Just 0.037 Volts... (Score:3, Interesting)

    by fahrbot-bot ( 874524 ) on Wednesday July 08, 2009 @02:49PM (#28626443)

    Because urea's four hydrogen atoms are less tightly bound to nitrogen than the hydrogen bound to oxygen in water molecules, it takes less energy to break them apart."

    Apparently, a lot less. From TFA: "Just 0.037 Volts need to be applied across the cell, against the 1.23 Volts needed to break down water."

  • Re:Urea? (Score:2, Interesting)

    by mcgrew ( 92797 ) on Wednesday July 08, 2009 @02:57PM (#28626589) Homepage Journal
    1. You misspelled "frosty"
    2. You weren't the frost psot
    3. this comment is offtopic
    4. ??????????
    5. Profit?
  • I love this idea (Score:2, Interesting)

    by ZeroSerenity ( 923363 ) <[moc.oohay] [ta] [50camrog]> on Wednesday July 08, 2009 @03:02PM (#28626657) Homepage Journal
    I'd never have to stop driving to relieve myself again. Just make sure I've got plenty of water handy.
  • Re:Way Cool (Score:2, Interesting)

    by Sefi915 ( 580027 ) on Wednesday July 08, 2009 @03:03PM (#28626671)
    Unfortunately, it wouldn't be a 100% efficient cycle.

    Due to human perspiration and respiration, not all of the water ingested by the driver/passengers/donors/etc would be returned as urea.

  • What if ? (Score:3, Interesting)

    by dword ( 735428 ) on Wednesday July 08, 2009 @03:13PM (#28626825)

    ... we run out of water, because we drink it all and instead of peeing it back on Mother Nature we break it into other particles?
    While this sounds rather strange, you should realize that it's only a matter of "when?" instead of "will it?" Just for the heck of it, does anyone have any idea how this period can be computed?

  • It worked in Rome (Score:2, Interesting)

    by liquidsunshine ( 1312821 ) on Wednesday July 08, 2009 @03:31PM (#28627125) Homepage
    The Romans made great use of human urine in their day; why shouldn't we do the same? In ancient Rome, citizens were actually "taxed" their urine; that is, the government required that they give it to them. And then they sold it back to them in more useful forms. Sounds like a great way to get our government out of the financial mess they're in!
  • Re:urinine (Score:2, Interesting)

    by Philip K Dickhead ( 906971 ) <folderol@fancypants.org> on Wednesday July 08, 2009 @04:50PM (#28628143) Journal

    Hey! Don't pee in my Cheerios here!

    I want a NITROGEN powered car. Then I can piss about, all over town.

  • by Anonymous Coward on Wednesday July 08, 2009 @05:16PM (#28628475)

    won't this produce large amounts of NO(x) pollutants?

  • by rcw-home ( 122017 ) on Wednesday July 08, 2009 @05:42PM (#28628767)

    When did they make volts a unit of energy?

    They made the Electron Volt [wikipedia.org] a unit of energy when they needed a way to describe how much energy difference there is between two particle states, for example the amount of energy needed to electrolyse a single molecule.

  • by Rei ( 128717 ) on Wednesday July 08, 2009 @05:51PM (#28628897) Homepage

    What about #1 [vefur.is]?

    Heck, here in the midwest, I'm in a university building that has central-source-heated steam pipes that not only run across the entire campus, but even cross under a river.

  • Re:The problem.... (Score:3, Interesting)

    by Artifakt ( 700173 ) on Wednesday July 08, 2009 @06:46PM (#28629487)

    Oil is two or more separable problems. Gasoline has environmental effects - we will never get it to burn cleanly enough in an application such as individual autos if they are at all widespread. The same goes for natural gas, ethanol, and all the alternates that involve any hydrocarbon compound - a few people with badly tuned engines can produce pollutants equal to what thousands of well tuned engines will produce, and even well tuned engines aren't really good enough when you expand use to hundreds of millions of consumers.

          Then there's the geopolitics of who has oil and who doesn't. That remains a problem unless you get a substantial majority of hydrocarbon compounds from elsewhere or get off of hydrocarbons.

          Here's the crux - there is a very real chance of both problems becoming critical. Nobody can make a real, high accuracy prediction of just how much damage our species will take because of burning so much oil, and nobody can make a high accuracy prediction of WW3 starting in the Middle East. We can't say the current rate of oil burning will contribute exactly X meters to sea level rise by year Y, and neither can we say that there is X probability of a brushfire war going Nuclear in year Y, but in both cases, some strong, negative consequences seem at least fairly likely. I don't think there are any good arguments that an environmental crisis will definitely be less serious for our species than a Nuclear war, or vice versa. We simply have to rate both as very grave risks with rather indeterminate deadlines for us to act.

          Every resource we waste finding ways to wean ourselves off of Mideast oil rather than off of oil in general is actually part of the bigger problem, because it does nothing about the environmental side, and we have better chances overall if we act as though the environmental side at least could be as critical.

          What puzzles me though, is what I don't see. For the environment, we have a substantial minority arguing that global warming is a hoax, and acting like the many other environmental consequences of burning so much oil somehow won't ever really matter just so they don't count as global warming. For politics, I don't see anybody claiming that the Mideast can't be the trigger-point for a major war. I also don't see anyone claiming that it won't be a big deal just so long as such a war doesn't go nuclear.

          My whole country reacted to a non-nuclear spill over of the continual middle eastern disagreement as though it were pretty damned serious back in 2001. Was there anybody announcing then that it didn't mean a major war was any closer, or the terrorists didn't use nukes so it was no big deal? What's made a substantial group behave this way when it comes to air pollution?

  • Wait a second (Score:3, Interesting)

    by Well-Fed Troll ( 1267230 ) on Wednesday July 08, 2009 @07:57PM (#28630213)
    Hold on a second. If the energy required to split urea into hydrogen is very small, you've just solved the hydrogen storage problem.

    Crack the urea on the fly to hydrogen and combust it down to water. What are the waste products of the electrolysis?

2.4 statute miles of surgical tubing at Yale U. = 1 I.V.League

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