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Crunching the Numbers on a Hydrogen Economy 396

mattnyc99 writes "In its new cover story, 'The Truth About Hydrogen,' Popular Mechanics magazine takes a close look at how close the United States is to powering its homes, cars and economy with hydrogen — including a calculation of where all the hydrogen would come from to meet President Bush's demands. Interesting that they break down the future of hydropower not by its advantages but by its challenges: production, storage, distribution and use."
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Crunching the Numbers on a Hydrogen Economy

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  • by tdemark ( 512406 ) on Tuesday October 17, 2006 @07:27AM (#16466003) Homepage
    Interesting that they break down the future of hydropower not by its advantages

    I do not think it means [reference.com] what you think it means.

  • by Anonymous Coward on Tuesday October 17, 2006 @07:33AM (#16466049)
    With a fuel cell in each house, you could essentially generate hydrogen from water and electricity at night when the power plants are idling in inefficient speeds. During the day, you could do the opposite and generate electricity from the hydrogen generated the previous night.

    Or you could do what most people do when they want hydrogen, heat a hydrocarbon with steam [wikipedia.org]. It is a hell of a lot cheaper than electrolysis! In fact, most fuel cells use some sort of hydrocarbon reforming to get their hydrogen. Unless you store hydrogen as a liquid, its energy density is just too low for any reasonable fuel tank.
  • by 140Mandak262Jamuna ( 970587 ) on Tuesday October 17, 2006 @07:54AM (#16466207) Journal
    We should recognize that there are two distinct energy sectors, and one is in crisis and the other one has some breathing space for a smooth landing.

    The fixed or stationary energy use, at homes, offices, and factories is not in as much of a crisis as the transportation sector. For electricity generation, there are alternatives like coal (yeah, it is dirty), or nuclear (yeah, most people fear it) or tar sands (yeah, it is expensive to recover) or wind (yeah, it has some problems), solar (yes, it needs high investment). There are problems, but USA is self suffiicient in them, and we wont be held hostage by foreign powers. There is breathing space to develop really good alternatives.

    On the other hand, in the transportation sector is in crisis already. So much of personal transportation depends on gasoline and freight depends on diesel and air transportation depends on kerosene. No serious alternatives are emerging and the time is running out on those sectors. Most predictions of peak oil is around now or 2010. Even the most optimistic estimates about the Hydrogen powered cars or biodiesel driven trucks talk about widespread adaptation around 2020.

    America is particularly vulnerable to this energy crisis. It is not as densely populated like Europe or Urban India and China. It is not easy to switch USA to use electricity driven public transportation. So much of the economy depends on the high home values of the sprawled cities and the humongous fleets of trucks delivering goods. So much of the infrastructure is built around the idea it is very cheap to transport goods over 100s of miles. And America is not self sufficient in this energy sector. This is a grave crisis.

  • Re:Coal to oil (Score:2, Informative)

    by suntac ( 252438 ) <Johan DOT Louwer ... inalcult DOT org> on Tuesday October 17, 2006 @08:08AM (#16466315) Homepage
    Aspo The organization who is doing research on when the oil consumption will peak and the available quantity has a new figure of the world running completely out of oil in 2050.

    http://www.peakoil.ie/newsletters/47/ [peakoil.ie]

    Other organizations and institutes a re backing those figures and they agree with this. Meaning that if the figures are correct we will run out in 2050, but as supplies start running out the price of oil will skyrocket.

    If they skyrocket this high the price will be to high to, for example, power combines for the harvest of food supplies. This is not a scenario for third world countries, this is a scenario we can expect to have in the US and Europe for example in 20 till 30 years. This is to say if we do not take quick action.

    There are solutions to extract fuel from coal, this is done by Germany in world war II when they had almost zero access to oil supplies but where in need of powering a war machine. The solution is today used in South Africa where they have a 28% fuel supply from coal liquefaction.

    Even do we are aware of the problem and even do we have a solution in place there is not very much initiative at this moment. We might run out of time. At least that is what I am worried about.
  • by AceJohnny ( 253840 ) <<jlargentaye> <at> <gmail.com>> on Tuesday October 17, 2006 @08:11AM (#16466335) Journal
    Maybe I'm taking you too literally here, but remember that no fuel cell system aimed at the mass market take pure hydrogen as an input, mainly because of it's inherent danger (think Hindenburg).
    Instead, they take some other compound, like ammonia or hydrides, from which they extract the hydrogen to power the fuel cell. The advantage is that at no point do you have a large enough quantity of hydrogen to cause an explosion.

    So my point is, generating the appropriate "fuel" for a fuel cell isn't as easy as electrolysing water to get it's hydrogen. You'll then want to combine that hydrogen with a carrier, which is what will be injected into your fuel cell. That's the complicated part.
  • Re:Innovation (Score:3, Informative)

    by nelsonal ( 549144 ) on Tuesday October 17, 2006 @08:14AM (#16466375) Journal
    They have energy independance because they found a bunch of oil off their coast. The E85 helped but contributes only a modest amount (just under 15% or so of oil use) to their overal fuel use. Also, corn is much less efficient at converting solar energy to ethanol, so the US would be relying on imported sugar or ethanol anyway. Brazil is only declaring energy independance because they also have a plentiful cheap resource today, namely petroleum.
  • by kfg ( 145172 ) on Tuesday October 17, 2006 @08:17AM (#16466409)
    Yes, hydrogen is a fuel, but it is not an energy source. It is a fuel you have to put the power into. The phrase "hydrogen economy" is an idiocy at best; a fraud at worst. The economy will be based on whatever source of energy is used to make the the hydrogen. Like, oooooooooooh, gas and coal.

    The more things change. . .

    Gasoline and diesel have to be refined -- it's not like we find them naturally in the ground.

    But the energy is already in the crude (stored solar) and it can be used to power its own refinement. There is a loss of available energy in the process, but a net gain nonetheless.

    There is nothing but net loss in hydrogen since any energy that can be extracted from it must be put in it the first place - and the Second Law wins. The current cheapest and quickest way to put energy into hydrogen is to . . .burn oil and coal. Using hydrogen as a fuel increases coal and oil use until the price of them rises above the cost of energizing hydrogen by other means.

    In other words, when hydrogen becomes really, really expensive itself.

    KFG
  • by nelsonal ( 549144 ) on Tuesday October 17, 2006 @08:19AM (#16466425) Journal
    From my understanding throughout the 20th century we've always had about 40 years of production in known reserves. The only valid arguement for peak oil is that the Saudis have been lying through their teeth about their reserves (the Matt Simmons arguement). He makes a good case, and certainly knows more about oil extraction than most of us.
  • by spectrokid ( 660550 ) on Tuesday October 17, 2006 @08:24AM (#16466467) Homepage
    Everybody building up his own little electricity depot can never be as efficient as a large-scale approach. An advantage of this scenario would however be that these depots would release heat both during charging and decharging. If you use them during the winter and heat up your house as a side effect, there might be a case. During the summer, forget it. Hydrogen is such a complex energy form it can only be profitable in places where you need to take your energy with you, e.g. your car.
  • by hcdejong ( 561314 ) <hobbes@@@xmsnet...nl> on Tuesday October 17, 2006 @08:30AM (#16466521)
    This is mentioned in TFA (second page, heading "SOLID-STATE"). IIRC there are more materials that can do this, collectively they're called metal hydrides. Metal hydride tanks are heavy and expensive: Mercedes built a car with a metal hydride fuel tank about 10 years ago, the tank alone cost $100k.
    The temperature needed to release the hydrogen is about 300 deg C.
  • Re:Innovation (Score:2, Informative)

    by kfg ( 145172 ) on Tuesday October 17, 2006 @08:37AM (#16466585)
    Rather than "it's about protecting the environment" we should be saying "it's about not being dependent upon the Middle East".

    How about telling the truth, just to be different?

    KFG
  • by tonicblue ( 764384 ) on Tuesday October 17, 2006 @08:47AM (#16466679) Homepage
    http://news.bbc.co.uk/1/hi/world/europe/2973885.st m [bbc.co.uk]
    http://www.hydro.com/en/press_room/news/archive/20 03_04/hydrogen_island_en.html [hydro.com]
    http://business.guardian.co.uk/story/0,3604,943132 ,00.html [guardian.co.uk]

    They don't just use hydrogen.
    Some cities, such as Reykjavik, already use hydrogen to power buses. But Iceland gets some electricity and over 80% of its heating and hot water from geothermal energy sources, and can produce the hydrogen emission-free. Other countries need to find ways to produce the hydrogen sustainably.

    http://www.newscientist.com/channel/earth/energy-f uels/dn9984 [newscientist.com]

    They are lucky they live where they do. It's a hot bed of free energy.
  • by Planesdragon ( 210349 ) <`slashdot' `at' `castlesteelstone.us'> on Tuesday October 17, 2006 @08:52AM (#16466753) Homepage Journal
    I've seen this prediction-of-doom vary from 10 years to 50 years.... projected at various points over the last 30 years. Chances are, you'll be able to see some headline in 2070: "Oil Running Out in 20 Years!!!"

    Amazing how you don't graps what "Peak Oil" really is.

    At a certain point, production stops increasing, and in fact starts to decline, because not enough new fields can be found to replace the spent ones. (When's the last time you saw a field of Oil pumps in PA?) The price of oil goes up, as the supply goes down -- making currently non-profitable oil reserves and energy sources, theoretically, more profitable.

    We will likely never run out of oil, although it will eventually (50 years? 500?) reach the point where it's simply too expensive to get the stuff out of the ground, and we only use biomass-made oil or some other alternative fuel source.
  • by orzetto ( 545509 ) on Tuesday October 17, 2006 @09:01AM (#16466879)
    no fuel cell system aimed at the mass market take pure hydrogen as an input, mainly because of it's inherent danger (think Hindenburg).

    That's because there are no fuel cells aimed at the mass market yet, except alcohol testers, which are anyway not a power source. Hydrogen is not more dangerous than gasoline; it does not concentrate on the ground but escapes high to the sky. You can neither be soaked in hydrogen. It does however have a lower threshold for ignition, but putting things together it is not especially dangerous. Thinking Hindenburg, less than half of crew and passengers actually died [wikipedia.org]. Try find that number in any plane crash with an equivalent amount of flames.

    Instead, they take some other compound, like ammonia or hydrides, from which they extract the hydrogen to power the fuel cell. The advantage is that at no point do you have a large enough quantity of hydrogen to cause an explosion.

    Wish it were like that, but if they contain the energy, hydrides, ammonia or whatever else can also burn. The idea is mostly to increase volumetric energy density, as hydrogen is very light and going around with a 70-MPa cylinder is somewhat unpractical (though not impossible).

  • Re:Innovation (Score:3, Informative)

    by Smidge204 ( 605297 ) on Tuesday October 17, 2006 @09:11AM (#16467013) Journal
    Way to take a quote out of context!

    Immediately before that quote: Skeptics say that hydrogen promises to be a needlessly expensive solution for applications for which simpler, cheaper and cleaner alternatives already exist. (Emphasis mine)

    In other words, for many applications Hydrogen is the Rube Goldberg machine of energy management.
    =Smidge=
  • by wowbagger ( 69688 ) on Tuesday October 17, 2006 @09:25AM (#16467245) Homepage Journal
    The Hindenburg fire was NOT caused by hydrogen, but rather by a new exterior covering that the Zeppelin company was trying out - a butyl rubber fabric coated with iron oxide and powered aluminum - in other words, a formulation very close to what the Space Shuttle Solid Rocket Boosters use for fuel.

    In addition, the skin panels were not electrically bonded to the superstructure of the ship and formed a series of capacitors which were highly charged - when the ship was grounded by the mooring lines, the panels discharged, some through the wet cords binding them to the ship, some by arcing (and thus setting themselves on fire).
  • by The_Wilschon ( 782534 ) on Tuesday October 17, 2006 @10:09AM (#16468003) Homepage
    According to the wikipedia article that you cite, the hydrogen used for buoyancy was not the main contributor to the flames, but rather a compound used to dope the fabric that formed the skin on the zeppelin.
  • by vhogemann ( 797994 ) <victor AT hogemann DOT com> on Tuesday October 17, 2006 @10:58AM (#16468993) Homepage
    Yeah, but with fossil fuels you're releasing NEW CO2 on the atmosphere... For fuel cells you're using Methanol, that can be obtained from sugar-cane. So any CO2 released was once at the atmosphere anyway.

    The real problem here is the space required by sugar-cane plantations. To be able to supply enougth methanol the plantations would have to grow over lands ocuppied today by other cultures (we still need food!), or the few preserved wild forrests that we have. Yes, I know we can harvest methanol from beats and other vegetables, but AFAIK sugar-cane is the most efficient.
  • by Anonymous Coward on Tuesday October 17, 2006 @01:12PM (#16472029)
    Yet another person who doens't know what distribution is? Here's one for you: most people have more than the average number of eyes, ears, fingers, and legs. Why? Because there are plenty of people missing some (and only a few with extra), so the average number of eyes is 1.9+ but less than 2.

    Now, the median is defined such that it's actually in the middle, so half are below and half are above it. So half of the world has lower than median intelligence.

    If you really wanted to defend that, you might instead point out that IQ tests are made to fit a normal distribution.
  • by HiThere ( 15173 ) * <charleshixsn@@@earthlink...net> on Tuesday October 17, 2006 @02:49PM (#16473911)
    As a statistician (out of practice) there are THREE common averages: The mean, the median, and the mode. In a normally distributed sample these values coincide.

    He's not wrong, merely imprecise. You might be considered either wrong, or ill informed. Your choice. I can't just pick overly critical, as that doesn't fit. (Well, it's true, but it's not the point I'm addressing.)

    It would have been more correct to point out that dumb means unable to speak rather than unintelligent. This is at least formally true.

  • by Ironsides ( 739422 ) on Tuesday October 17, 2006 @03:55PM (#16475085) Homepage Journal
    (And if you ask me, nuclear is not the holy grail, unless they get fusion going).

    The main problem with Nuclear today is the absence of recycling the material after it has been in the reacotr. Once we get breeder reactors and a recycling program going, nuclear gets a lot cleaner.
  • by Patrick Russell ( 1014767 ) on Tuesday October 17, 2006 @08:33PM (#16478829)

    Just because you can disproove Incendiary Paint Theory still doesn't mean such disproof will proove the paint wasn't a catalyst that further ignited the hydrogen.

    Ah, but the whole basis of Bain's theory (especially as it is used to counter the Hindenburg objection when discussing hydrogen's potential as a fuel) is that the hydrogen was incidental to the fire, and that it was the cover and not the hydrogen which was the fire's primary accelerant.

    Bain tried to claim that the Hindenburg would have burnt just the same had it been filled with helium, and therefore hydrogen was not to blame for the Hindenburg disaster. Of course, Bain's claims seem to have changed as more and more of his theory was debunked (last I heard he was apparently claiming that it was engine exhaust which somehow wafted up to the top of the ship and caused the fire, so consider the source here) but when his theory was still new and unchallenged, he was trying to say that the outer cover was SO flammable that an airship filled with non-flammable helium would have burned exactly the way the Hindenburg burned. Hence, the inevitable conclusion would go, hydrogen is safe to use as a fuel.

    Now, I believe hydrogen IS safe to use as a fuel, at least given the fact that we regularly use a combustible fuel like gasoline and consider it safe. Don't misunderstand me... I am a big proponent of the development of alternative fuel sources. I'm not arguing against Bain's theory for the sake of attacking alternative fuels.

    However... Dessler, Overs, and Appleby have proven (by an easily replicated burn test) that the Hindenburg's outer cover, on its own, would have taken 40 hours to burn. A helium airship with this same covering under the same conditions would NOT have burned in 32-34 seconds as the Hindenburg did.

    Could the outer cover have been the initial source of a small, slow-burning fire that ignited the ship's hydrogen and led to the disaster? Possibly. However, I have yet to see Bain actually replicate the ignition of the cover using the same static discharge that would have been present atop the Hindenburg. In various documentaries on the matter, I've seen him light fabric samples using an open flame, and using a high-voltage charge from a Jacob's Ladder, neither of which are remotely the same thing as the type of static discharge that would have ignited the Hindenburg.

    A far more likely possibility as far as the fabric helping to generate a static discharge that would have ignited the hydrogen is this: The outer cover was isolated from the ship's framework by wooden shims up to a centimeter thick which had been glued along the longitudinal frames in a number of places (especially in the stern of the ship) to help tighten the outer cover (which was noted to be unusually loose during the ship's early flights.) Now you've got a gap between cover and framework across which static can arc, and in which loose hydrogen could easily be present if we're talking about the very top longitudinal girders atop the ship.

    And this really comes back to the theory that Dr. Eckener had in 1937, and which he held for the rest of his life... free hydrogen was ignited by a spark between the outer cover and the ship's framework.

    But again, either way, it was the hydrogen which was the real problem there. Had the Hindenburg been filled with helium, it simply would not have burned the way it did, even if the cover HAD somehow started on fire atop the ship. They'd have had plenty of time to get the ship landed and the passengers disembarked, and then you'd have probably seen riggers and mechanics climbing up inside the hull with fire extinguishers to douse the fire. The ship wouldn't have sailed back to Germany that night as intended, of course, but they'd have almost certainly saved it and repaired it.

    And, of course, if the Hindenburg fire wasn't anything to do with any cover fire, if the whole thing was just as Eckener theorized, free hydrogen being ignited d

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