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The Physics of the Hydrogen Economy 501

Posted by michael from the trickle-down dept.
Spy der Mann writes "A Physics Today article entitled The Hydrogen Economy explores the possibility of using hydrogen as an energy source. The article explores the current methods, limitations, and the need for more research. For those wanting to point out the Hindenburg incident, the article doesn't talk about gaseous hydrogen only, but also about hydrogen fuel cells. My favorite quote: 'The natural world began forming its own hydrogen economy 3 billion years ago, when it developed photosynthesis to convert CO2, water, and sunlight into hydrogen and oxygen'. Interesting read for eco-fans."
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The Physics of the Hydrogen Economy More

The Physics of the Hydrogen Economy

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  • Popular Science (Score:5, Informative)

    by BobPaul ( 710574 ) * on Tuesday January 04, 2005 @05:54PM (#11258157) Journal
    This looks like something I read in January's Popular Science last week! [popsci.com]

    • Hydrogen is a Boondoggle - Biodiesel (Score:5, Interesting)

      by StCredZero ( 169093 ) on Tuesday January 04, 2005 @06:27PM (#11258487)
      Hydrogen is a Boondoggle. [dotynmr.com] The energy density is so low, that we might as well use batteries if we're going to power vehicles with it. (It may be good for stationary purposes.) If we really wanted to, we could convert all US vehicles to diesel, and run them all with Algae-Derived Biodiesel [unh.edu] using sewage as a feedstock. Because of the greater efficiency of algae, supplying all of our vehicular needs is actually feasible.

      This would alleviate both the global warming problem and our dependence on Middle-Eastern petroleum. The technology is available now, and because of the high energy density, no sacrifices on the part of automotive consumers are required in terms of range and performance. (We may need to invest in research into better catalytic converters and turbocharging technology.)
      • Ditto with the Biodeisel being tested in Vancouver, BC, Canada in the transit system, made from Canola (yes, it's incredibly toxic as a plant, but we have a million acres of the stuff, might as well use it!).

        Bonus: the exhaust smells like French fries.

        • Bonus: the exhaust smells like French fries.

          Yes, definitely research into better catalytic converters! Or, Stirling Cycle series hybrids! [4brad.com] Since Stirling engines are external combustion, we can tailor conditions to acheive nearly complete combustion.
          • Actualy a lot of work is being done on Stirling engines. One thing they would be good at is exhaust gas waste heat reclaimation, where a good amount of a gasoline or Diesel engine's losses occur, hot exhaust. Suck up the waste heat and run a generator with it.
            Stirlings would be interesting in private aviation, present engines use leaded gasoline which is getting scarcer and more expensive. Swithching to stirling's would alow the average person to own a plane that not only burned Jet A fuel, but also develop
        • No canola is not incredibly toxic. No idea where you got that idea. There are some crackpots here in the US who try to spread FUD about it. Rapeseed oil could be thought of as toxic (although people in India actually use it in cooking), but Canola oil is most definitely not toxic. Canola is grown right now exclusively for food oil.
      • How does this alleviate global warming? Does biodiesel not release carbon dioxide when it burns?
      • One of the leading CEO's of an energy company
        was interviewed by Charlie Rose recently. He
        stated that the most cost effective source of
        hydrogen was to strip it off of natural gas.
        I see a really big problem with that solution --
        to be truly environmentally friendly, the new
        "hydrogen economy" cannot use a carbon-based
        source. The resultant byproduct, carbon dioxide,
        is also a greenhouse gas. The only way to have
        an effective "zero sum" energy solution is a
        non-polluting (hydro/wave/solar/geothermal)
        source of ele
      • Yes, the energy density is quite low, and that's a big fundamental problem. There doesn't seem to be anything on the horizon to get a reasonable amount of range out of hydrogen powered vehicles without creating a host of other major problems.

        But the real issue is this: Why on earth are we requiring vehicles to carry around their power supply in the first place, except for "backwards compatability"? Fully automated magnetic-propelled cooperative personalized elevated-track-riding vehicles (full door-to-do
        • There are two things standing in the way: The automobile lobby and the big oil lobby. It is also worth noticing that while building this system would create many jobs, finishing it would destroy many, MANY jobs; all that road maintenance, auto production (if all cars ride the same track and no car can exceed the speed limit, then there is no motivation to buy new cars) and so on. Also, how are you planning to accomodate people who live in remote locations, and handle moving freight and building supplies to
          • Well, "big oil" (which I'm closely related to) would be happy to supply the oil for the power - after all, oil and coal are where we get our current power. They might not like the increased energy efficiency, mind you. However, the automobile lobby would be glad to be making brand new vehicles that everyone is going to need. :) And even after everyone is "updated", styles change - and even though things will wear a lot more slowly with the greatly simplified propulsion, unless you go straight to maglev f
        • Cute idea, but I think "staggering capital costs" is the world largest understatement. First off, you are talking about what would be by far the largest government project ever even conceived. It would make the current combined spending of the US government look like pocket change. You couldn't even contemplate such a thing without turning your entire economy over to the effort. You would need greatest tax hike in American history to fund it. No, even disbanding the military wouldn't even begin to cove
    • Similar article in Wired [wired.com] a year and a half ago

  • FEAR HYDROGEN (Score:3, Funny)

    by Anonymous Coward on Tuesday January 04, 2005 @05:55PM (#11258163)

    I have to post this as an AC to keep my identity secret. The government created hydrogen in 1897 and altered all history books to reflect otherwise.

    Background: I work as a research scientist in a secret government lab deep under the Nevada desert. There are a few things the public needs to know about hydrogen.

    FACT: Hydrogen was NOT discovered by Henry Cavendish in 1776 as the books say. Read on...
    FACT: in 1892 the US government was experimenting with ways to weaponize a new substance that was discovered at an alien crash site in New Mexico. The military knew that this substance, used as fuel in the alien ship, could be weaponized which would allow the US to take over the world as part of its Pax Americana goal.

    FACT: in late 1894 a spark in the secret lab caused the fuel to chain react. It destroyed several square miles of land and created a crater in Arizona. The history books were re-written to suggest that Barrington Crater in Arizona was in fact created by a meteor eons earlier. The fact is that Dr. Hymie Barrington was the person who sparked off the largest explosion until that time on the planet.

    FACT: A byproduct of the fusion was a toxic product the government called "Hydrogen". So much of the hydrogen was released that it is now found virtually everywhere on Earth. Recent measurements show that common water is now 2 parts hydrogen to one part oxygen.

    FACT: The US wanted to scare people into not using hydrogen. That is why they engineered the Hindengberg disaster in 1937. An oilman at the time, Wallace Bush (sound familiar?) knew that hydrogen could ruin his new buisiness of oil drilling. Bush, along with Herman Cheney (another oilman) rigged explosives in the Hindenberg back in Germany and ectivated them by remote control when all the cameras were rolling.

  • A friend and coworker was describing a scene he witnessed at a plant that liquifies gasses. You figure out which one.

    One of his coworkers was pushing a metal cart loaded with a test rig down an aisle. About halfway down there was a huge *whump* that echoed down the hall and the entire front half of the cart was in flames. The man wasn't seriously injured, even being so close to a tremendous fire.

    A H2 pipeline had ruptured (H2 embrittlement I think he said) and was spewing a steady stream of the material in a jet across the walkway. Somehow it had caught fire and, since H2 burns colorless no one saw it.

    Had that cart not been there.... ouch.
    • Someone in the Navy told me they used to look for high pressure steam leaks with a 2x4, as the steam was so hot that it would ignite the 2x4.

      • Looking for steam leaks (Score:5, Informative)

        by Old Man Kensey ( 5209 ) on Tuesday January 04, 2005 @07:14PM (#11258907) Homepage
        My dad worked in two nuclear power plants and on several naval vessels (some nuclear) as a welder. He says the same thing about looking for steam leaks (with a broomhandle instead of a 2x4), but it's not because the steam will ignite the wood -- it's because those leaks may be thousands of PSI. What you're looking for, is for the end of the broom to suddenly fall off as the steam pressure carves it right in two.
    • No kidding. I work with high pressure Hydrogen (both making & consuming 100s tons/day). We issue and instruct our operators to wave around corn brooms when checking for leaks (yes, the flames are often invisible torches). You can hear the leaks, and most often we just depressure to flare.

  • I claim all copyright (Score:4, Funny)

    by EnronHaliburton2004 ( 815366 ) on Tuesday January 04, 2005 @05:58PM (#11258202) Homepage Journal
    'The natural world began forming its own hydrogen economy 3 billion years ago, when it developed photosynthesis to convert CO2, water, and sunlight into hydrogen and oxygen'.

    Well, as the official sponsor of the Big Bang, I claim all copyright on that whole electrons and protons forming into a 1-1 molecule and will hereby sue the ass of any plant who dars to reverse engineer my process to produce Hydrogen

  • Hindenburg (Score:2, Informative)

    by Anonymous Coward
    The real problem with the Hindenburg wasn't the Hydrogen inside, it was the flammable skin-coating on the outer covering. The Hydrogen alone wouldn't have reacted so wildly.

    • Re:Hindenburg (Score:5, Informative)

      by crow ( 16139 ) on Tuesday January 04, 2005 @06:02PM (#11258249) Homepage Journal
      Not to mention that it was designed to be used with helium, not hydrogen. However, the only source of helium was in the United States which had restricted exports to Germany in response to the rise of the Nazis.

      • Re:Hindenburg (Score:4, Informative)

        by Sebastopol ( 189276 ) on Tuesday January 04, 2005 @06:05PM (#11258281) Homepage
        I saw an PBS documentary that said it went up because it was painted with solid rocket fuel: aluminum powder and iron oxide. They said the hydrogen would have escaped before it had a chance to ignite and explode.

        Now as for a compressed H2 tank exploding in a car, that seems more likely.

        But IANAPhysicist.

        • Re:Hindenburg (Score:3, Informative)

          by museumpeace ( 735109 )
          Well, I have a BS in physics. Chemistry would do even better for settling this. Anyway, the powdered Al and iron oxide in the paint on the Hindenburg is essentailly the same formula as thermite [intekom.com], an incindiary bomb ingredient and also used in industrial welding.

    • Re:Hindenburg (Score:3, Informative)

      by BobPaul ( 710574 ) *
      The real problem with the Hindenburg wasn't the Hydrogen inside, it was the flammable skin-coating on the outer covering. The Hydrogen alone wouldn't have reacted so wildly.

      Ever burned a ziplock back full of hyrdogen? Once the flame burns through the bag there's a pretty big "poof". I don't know what you're talking about with hydrogen not reacting wildly, because it's violent as most other inflamible substances.

      And what's this have to do with the article anyway?
      • This small-scale experiment doesn't really do justice to the common saying that hydrogen doesn't burn wildly. What is really meant by this is that burning hydrogen is less likely to kill humans than people seem to think.

        After your plastic bag experiment, you think of hydrogen as an explosive. It really isn't, not in large quantities - essentially you will get a longer poof, but not a louder one. The burn rate is limited by the mixing of air with the hydrogen, and that is limitted by the heat created by

  • 2 remarks: (Score:4, Insightful)

    by Roland Piquepaille ( 780675 ) on Tuesday January 04, 2005 @06:01PM (#11258234)
    1- Re the Hindenburg incident: there is now fair evidence that the whole thing happened not because the hydrogen is flamable (it was in airtight balloons, and any hydrogen leaking out was highly vented), but because of the envelope fabric, that had cellulose acetate butyrate coating, which is highly flamable and prone to cause static electricity. If the blimp had been filled with helium, a ravaging fire would have engulfed its skin anyway, but with less violence. The hydrogen gas here was a facilitant more than a cause of the disaster.

    2- Hydrogen is only a vector. It is not an energy source, it's only a way to carry energy created elsewhere. There is no "hydrogen economy", just the existing energy economy with an additional vector that can be compared to batteries.

    • Re:2 remarks: (Score:3, Informative)

      by harks ( 534599 )
      Your remark number 2 is emphasized in the article, and the article goes over ways to aquire hydrogen through clean renewable methods.
    • 2- Hydrogen is only a vector. It is not an energy source, it's only a way to carry energy created elsewhere. There is no "hydrogen economy", just the existing energy economy with an additional vector that can be compared to batteries.

      Couldn't you say the same for any energy source? Oil is just a way to carry energy created elsewhere...
      • Couldn't you say the same for any energy source? Oil is just a way to carry energy created elsewhere...

        And if you could drill for elemental hydrogen, it'd make sense to talk about a "hydrogen economy".

    • Well, technically that is true. Nuclear fusion merely converts the energy stored within the structure of the nucleus of the atoms involved into a directly usable form. The energy already existed.

      (See Also: Law of Conservation of Energy)

      Nonetheless, I'll take fusion over chemically stored energy any day. And if I have to use chemical energy, I'll take chemical energy that I can easily regenerate. (You can't make oil by mixing hydrogen and carbon, at least not without a lot of photosynthesis, anaerobic br

    • Re:2 remarks: (Score:3, Insightful)

      by dcmeserve ( 615081 )

      Hydrogen is only a vector. It is not an energy source, it's only a way to carry energy created elsewhere. There is no "hydrogen economy"...

      Actually, I think the term "hydrogen economy" is actually quite apt -- it's like "cash economy" or "barter economy" -- i.e. the first word refers to the medium of exchange, not what's actually driving things.

    • Re:2 remarks: (Score:3, Informative)

      by eofpi ( 743493 )
      The fact that the Hindenburg's paint pigments are the same compounds that are now the two main active ingredients in the space shuttle's solid rocket boosters has more to do with the fire than anything else. And, according to a Popular Mechanics article from sometime around 1996, the same thing happened in California in 1936 to another airship--this time filled with helium. So the hydrogen in the Hindenburg didn't do anything but exacerbate the existing fire.

  • Is it just me...? (Score:5, Interesting)

    by jdray ( 645332 ) * on Tuesday January 04, 2005 @06:02PM (#11258258) Homepage Journal
    Is it just me, or should there be a distinction between "energy source" and "fuel?" If you burn gasoline, hydrogen is still the component providing the energy. So talking about using pure hydrogen versus hydrogen bound up with carbon (and other atoms) is a difference in fuel makeup than the energy source.

    Or so it seems to me...

  • Hydrogen is not a power source! (Score:5, Informative)

    by Urkki ( 668283 ) on Tuesday January 04, 2005 @06:05PM (#11258280)
    Hydrogen is energy storage and transfer medium, not a power source. At least not in what is generally called "hydrogen economy". It takes a lot of energy to make Hydrogen (H2) in large amounts, and only quita s small portion of that "original" power is regained when the Hydrogen is later used as fuel.

    Of course fusion power would use Hydrogen as power source, but that's a totally different issue, and it happening is probably much farther in the future than "Hydrogen Economy"...

    • I was debating hydrogen with a Green Party person once. He claimed that hydrogen WAS an energy source and that if you hook two hydrogren "batteries" together, they will create even MORE energy. Needless to say, I ended the conversation there.

      This is the same Green Party person who later told me that: "sure, fascism sounds scary, but it might be just what we need to save the earth from ourselves."

  • Photosynthesis makes Hydrogen? Umm... (Score:3, Informative)

    by KingFatty ( 770719 ) on Tuesday January 04, 2005 @06:06PM (#11258289)
    But I always thought the byproducts of photosynthesis were carbohydrates and oxygen, not oxygen and hydrogen as the article suggests? Hydrogen is used as a source in the photosynthesis process (usually taken from water), not produced as a result.
    • Photosynthesis as found in plants generates carbohydrates and oxygen, but if you remove the organic component all you are really doing is using light to split water into hydrogen and oxygen; IIRC, this is a difficult thing to copy in a test tube.
    • I was going to make this point if nobody else had...

      Microorganisms have little use for molecular hydrogen; what are they going to do with their hard-earned energy, vent it as gas? Fixing carbon for energy and structure is their goal, and fats and carbohydrates are nearly perfect for those needs. (Fatty acids and hydrocarbons are very similar chemically.)

      Using molecular hydrogen for e.g. vehicular power is problematic; we could learn something from plants if we used carbon as a carrier for hydrogen instead

  • SHAM! Hydrogen is like a magic genie.. (Score:2, Informative)

    by Anonymous Coward
    Hydrogen is like a magic genie..

    Everyone can agree it is a good thing, but nobody knows how to get it.

    Where do we get it? If we use solar panels to create hydrogen, it would be far more efficient to just use the electricity then to convert it to hydrogen. In reality most hydrogen we make comes from reformed gasoline, thermodynamics tells us that wed be better off just burning the gasoline in the first place.

    The hydrogen economy is a bush sham.
    Everyone in the DOE knows it
    Everyone in the DOE who said it
    • Anonymous coward, Score 0, but he has a point.

      Conversion to hydrogen is an inefficient process. Why would you burn hydrogen in you car if you can have an all electric motor, exchanging batteries at 'pump' stations?

      Solar*(inefficient conversion rate)->Electricity*(inefficient conversion rate)->Hydrogen*(inefficient conversion rate)->Power

      Solar*(inefficient conversion rate)->Electricity*(inefficient conversion rate)->Power

      Which one is better?
      Sure you have the whole 'batteries don't hold eno

  • They keep delaying (Score:2, Insightful)

    by Funk203 ( 843953 )
    Ive have heard reports for years about Hydrogen but I havent seen nearly as much progression as they've said. They keep saying in a couple years but they really neeed more technology advancement to make it more practical.

    One prolem i think is that oil companies have been blocking the development because it would take away a huge market for them. They would lose tons of money if Hydrogen became a practical resource.

    • That doesn't make as much sense as you might think, because the oil companies...well...are running out of oil.

      In the US at least, we've got plenty of coal for what looks like another 100+ years (if we can deal with or mitigate the consequences,) and we're up to our necks in wind and solar (though the prices have to come down a little more on the former and by about another half on the latter,) but no matter where you look, the smart money's on the entire world having another 50 years' worth of oil - on the

    • and look at it whenever someone comes alogn with an awesome idea, they patent it, and the oil companies buy up the patents for ungodly sums of money. sad.

    • If hydrogen takes off, you'll see the "oil companies" quickly become the "hydrogen companies". After all, they're the ones with fuel distribution expertise. Where are you going to fill up your hydrogen-powered car? At the gas station (and finally, Brits and Americans will agree on what their cars' fuel is called!)

      Odd bit in TFA: "internal combustion engines can be rather easily modified to run on hydrogen instead of hydrocarbons." Is that so? I understand why jets can be converted easily, but my Honda can

    • Urban legend, the oil companies died a long time ago and were replaced by energy companies. The potential profits converting the world from oil to hydrogen are staggering. Who is making the majority of hydrogen right now, your nefarious Oil Companies that's who. These guys have a woody that will not quit thinking about the money they'll make from hydrogen.

  • I think the physicists are just looking for work.. (Score:5, Informative)

    by museumpeace ( 735109 ) on Tuesday January 04, 2005 @06:13PM (#11258370) Journal
    I should know, I never could get work as a physicist:-( There are other [ncpa.org] analyses [nature.com] that say a hydrogen economy is a daydream. you still have to GET the energy from some where If that is to be done without further burning of fossil fuels, we have to commandeer a huge amount of land for solar and wind farms and those are political and financial undertakings that are NOT an easy sell. Especially when the biggest fossil burning country reneges on Kyoto accords and is run by former president and vice president of oil or oil services companies.

    • 100 miles x 100 miles of Nevada desert would power the entire nation with photovoltaics, but the thing is...

      PV goes on roofs. Oil wells do not. Look out the window next time you fly into LAX or Dallas...we do need a lot of land for solar. It's just that we've already built stuff on most of it.

    • Ah, but you can use fossil fuels much more efficiently if they are ultimately used to product hydrogen. Because, you can switch between different sources of fuel easily; in other words, oil producers will have to compete with other sources of energy. Currently oil has a monopoly on that which depends on internal combustion engines, and if oil producers crank up the price a few notches we can't all go, "Oh, I'll just use 26% less oil for energy for my car this week" you'll still have to use 100% like you do

  • why not a diesel economy? (Score:5, Insightful)

    by avandesande ( 143899 ) on Tuesday January 04, 2005 @06:15PM (#11258389) Journal
    diesel requires no new infrastructure, and we can gracefully move to biodiesel as the oil reserves are tapped out.
    Why is this only obvious to me? Why can't I buy a honda civic with a diesel?

    • Re:why not a diesel economy? (Score:4, Informative)

      by athakur999 ( 44340 ) on Tuesday January 04, 2005 @06:19PM (#11258416) Journal
      You can buy a diesel Civic in other parts of the world. We're screwed in the US though...

    • Biodiesel, anyway you look at it, is indirect solar energy.(The same could be said for fossil fuels, but it's billions of years of built up solar energy) Moreover, if demand increases, the components will become more sparse and expensive.

      IIRC, there was an article a while ago about how someone was making biodiesel for something like $0.30 a gallon, but he was getting all kinds of used resturaunt fat for free- and it wouldn't be free for very long if it becomes an ingredient in widely used fuel.

      Moreover, f

  • Environmental effects? (Score:4, Informative)

    by SirGarlon ( 845873 ) on Tuesday January 04, 2005 @06:17PM (#11258408)

    The article makes no mention of the potential environmental effects of large-scale hydrogen production. To make hydrogen, you could use a nuclear reactor as suggested but that produces nuclear waste. You could invent some kind of biochemical method but that will probably require living cells and large quantities of clean water - which is also needed by growing human populations. The solar method is clean when working but the photochemical cells would probably be quite toxic.

    I do not think the "hydrogen economy" will provide limitless clean energy without any environmental costs or risks.

    • Re:Environmental effects? (Score:4, Informative)

      by WOV ( 652967 ) on Tuesday January 04, 2005 @06:26PM (#11258481)

      Solar cells are not as toxic as people seem to offhandedly suppose...they're etched silicon for the most part, though as you microelectronics folks know, there's solvent risk that has to be managed there. See this PDF for more info.

      And to head off the unresearched "solar takes more energy to make than you get from using it" canard that always shows up in these threads, I recommend the notes and bibliography at NREL, keeping in mind that the newer systems are closer to the lower numbers from this somewhat aging report.

      Now, all that said, you have a good point; no energy is completely free...what we *really* have to do is become quite a bit more efficient with how we use it...

  • Um, did ANYBODY read the article? (Score:5, Informative)

    by apsmith ( 17989 ) * on Tuesday January 04, 2005 @06:27PM (#11258497) Homepage
    So far I haven't seen a single comment relating to the actual content.

    The article isn't about how wonderful the hydrogen economy will be etc. etc. Nor is it about the Hindenburg. It's about the immense basic science challenges that will likely prevent any commercial viability for decades...

    Given that the article was directed at research physicists (readers of Physics Today), the intent was probably to motivate people to look into these challenges as basic science research areas for their labs.


    A host of fundamental performance problems remain to be solved before hydrogen in fuel cells can compete with gasoline.


    The main reason they think there's any point at all is because of the energy conversion efficiency of fuel cells, and the natural link between fuel cell use and hydrogen. But as the original post implies, one of the best ways to store hydrogen is in the form of hydrocarbons:


    Figure 4 shows the volume density of hydrogen stored in several compounds and in some liquid hydrocarbons.7 All of those compounds store hydrogen at higher density than the liquid or the compressed gas at 10 000 psi (700 bar), shown as points on the righthand vertical axis for comparison. The most effective storage media are located in the upperright quadrant of the figure, where hydrogen is combined with light elements like lithium, nitrogen, and carbon. The materials in that part of the plot have the highest mass fraction and volume density of hydrogen. Hydrocarbons like methanol and octane are notable as highvolumedensity hydrogen storage compounds as well as highenergy density fuels, and cycles that allow the fossil fuels to release and recapture their hydrogen are already in use in stationary chemical processing plants.

  • Hydrogen pollution (Score:3, Informative)

    by Shannon Love ( 705240 ) on Tuesday January 04, 2005 @06:28PM (#11258507) Homepage
    Diatomic hydrogen is very rare in the natural environment but can catalyze many reactions. There is no telling what effect on air quality, soil chemistry, material erosion etc may result from the leakage of large amounts of hydrogen from a large scale hydrogen-fuel system.

    Every technology has its unexpected negative consequences.

  • Though the article is cautiously optimistic, it did mention some serious problems. First is that fuel cells currently cost about 100 times than a gasoline engine for the sme power. Second, the storage energy density of gasoline is 4-10 times better than hydrogen.

  • Iceland and Hawaii (Score:4, Interesting)

    by Ralph Spoilsport ( 673134 ) on Tuesday January 04, 2005 @06:43PM (#11258632) Journal
    will be the next "Saudi Arabias" - why?

    1. Huge vast amounts of Free Energy, courtesy of plate tectonics.

    2. They are completely surrounded by all the water they could ever want.

    All you have to do is drill down to the heat, use it to boil water to spin turbines, which then make electricity to crack the water to make the hydrogen. Done.

    You heard it hear first. The amount of energy under Iceland and the Big Island is *insane*. Another good place to drill for heat would be the supervolcano at Yellowstone. Use the electricity generated there and you can pump in the water from most anywhere and crack it into H2. Also: by draining off some of the heat from the supervolcano, we might be able to prevent (or slow) the eventual eruption of that sucker.

    Problem solved. Next?

    HW

  • Safe (Score:2, Informative)

    by t_allardyce ( 48447 )
    This is one of the few things I remember from chemistry.. we watched a video where they had various tanks of gases, they put them in a field and shot that them, then tried the same experiment but with a spark generator near-by. Can't remember the exact results except the conclusion that Hydrogen was pretty safe. The Hindenberg was something to do with the skin of the airship.
  • Hydrogen is a fuel, not a source of energy. All we can really hope to use it for is as a clean and efficient way to transfer energy from other sources such as solar and wind. The real fact of the matter is that we can use hydrogen today. It would require a world war 2 sensibility to make the switch however. We could use solar, hydro, wind, and coal to provide the energy to derive hydrogen from water. At the same time, while we are building the distribution infrastructre we need to be retrofitting our v

  • Let's not forget entropy (Score:3, Interesting)

    by Angst Badger ( 8636 ) on Tuesday January 04, 2005 @06:53PM (#11258716)
    All of these discussions on novel means of energy production are well and good -- hydrogen, wind, solar, and several other approaches are quite promising. What seems invariably to be forgotten is that entropy, chiefly in the form of waste heat, is a limiting factor.

    The executive summary version of this fact is that if the entire population of the earth were consuming energy at the same rate as Americans, the atmosphere would be incandescent with waste heat.

    The obvious consequence of this -- and something which rarely receives any exposure on Slashdot unless it involves white LEDs -- is that producing more energy is not a viable long term goal; only conserving energy is. Even were this not the case, the current growth rates for energy consumption would lead to the exhaustion of even uranium for fission in a relatively small number of generations.

    Arguably, the worst thing that could happent to the human race would be the practical availability of an effectively unlimited source of power like fusion. If fusion power proved to be anywhere near as cheap as its proponents claim it would be, all economic incentive to reduce consumption (and therefore waste heat production) would be eliminated. While it would be theoretically possible to offset some of this by moving production offplanet, the economic barriers would be steep. Considering the reluctance of our species to deal with the current manmade environmental effects of industry, there is little reason to be optimistic.

    Alternative energy proponents all too often sound as if they were discussing perpetual motion machines. It is not possible to escape the Second Law of Thermodynamics. Some machines are more efficient than others, to be sure, but there is a theoretical limit and it is not a generous one. Beyond that limit, which is seldom even approached, all you can do is shuffle the wastage around; you cannot eliminate it.

    This is not something anyone likes to hear, and I suspect that is why it is so universally overlooked. There is a utopian vision shared by technologists and science fiction devotees (and I count myself in both camps) in which technology will someday give us everything we want. Unfortunately, "everything we want" violates the laws of thermodynamics, and those laws appear unlikely to be repealed.
    • The executive summary version of this fact is that if the entire population of the earth were consuming energy at the same rate as Americans, the atmosphere would be incandescent with waste heat.

      Are you on crack? Look at New York is it hot or cold in the winter? The amount of energy used by us humans is TINY when compaired to say the amound of solar radiation that lands on the earth each and every day and the net tempature of the planet stays constant because all this energy is radiated back out into s
    • "...producing more energy is not a viable long term goal; only conserving energy is..."

      This reflects a profound ignorance of the way that technological progress works.

      If you told someone in 1880 that the New York of 2004 would have a population of 8 million that would have said, "that is totally impossible! Do you have any idea how much horse manure a city of 8 million people would produce?"

      Likewise, the 1880 individual would not believe that individual transports capable of routine travel at a 100k

    • You're 100% correct about entropy and growth(*). Some other things are simply incorrect. But what I really don't like is your POV on these things:

      The executive summary version of this fact is that if the entire population of the earth were consuming energy at the same rate as Americans, the atmosphere would be incandescent with waste heat.

      Pure BS. As other posters pointed out, the extra energy is tiny and the radiation heat transfer into space still works very good (despite all the greenhouse gases). In

  • Hydrogen is not an energy source (Score:3, Insightful)

    by taustin ( 171655 ) on Tuesday January 04, 2005 @07:17PM (#11258932) Homepage Journal
    It is a storage medium. And it is not perfectly efficient. Ergo, when the article says "It takes energy to split the water molecule and release hydrogen, but that energy is later recovered during oxidation to produce water." what it means ks that "later some of that energy is later recovered.

    Hydrogen must take more energy to produce than you can recover from it. So our hydrogen economy is not a hydrogen economy at all. It is an economy based on some other energy source, with an exchange rate, like currency, where you lose a little to the money changer in every transaction.

    So where do they imagine that energy will come from? Solar? Unlikely. Hydro? Simply not enough to supply the world's needs. Geothermal? Also not enough. All of it combined isn't enough.

    And if it is enough, why waste some of it converting it to hydrogen, then back to electricity? Why not just use it directly?

    The whole concept of a "hydrogen economy" is a sham. Or a scam. Somebody's making a lot of money on all that research.

    But no matter how much research you do, you cannot turn hydrogen in to an energy source. It does not occur in nature in a usable form.

  • Lousy writing... but did you read it? (Score:5, Insightful)

    by delibes ( 303485 ) on Tuesday January 04, 2005 @07:45PM (#11259216)
    I have two complaints; one about the article, and the second about other posts.

    First, I hate that the article contains the submitter's favourite: 'The natural world began forming its own hydrogen economy 3 billion years ago, when it developed photosynthesis to convert CO2, water, and sunlight into hydrogen and oxygen'. What crap. Photosynthesis generates saccharides - chains of sugars, which are used by plants in to generate energy from respiration, just as animals do. There may be a brief moment where water molecules are split into H. and OH. radicals, but no hydrogen gas is produced or used as an energy store. Bury the plants deep undergound for a few million years and you have fossil fuels, not hydrogen gas pockets.

    Now, for those of you pointing out how crap hydrogen's energy density is - you're right! It sucks. It's so hard to deal with the stuff. I mean, the only way they make it work for the Space Shuttle is to deep freeze it so that it liquifies, and it takes yet more energy to cool it down which makes it suck more...

    If you read the article, it admits that using hydrogen in vehicles is very challenging. A tank full of H2 is unlikely to ever happen on this planet. Instead, the suggested vehicle storage solutions include nanostructure materials, surface absorbption/adsorption, or ionic compounds. However, cars and planes are not everything in the world. H2 gas could be used in homes and businesses instead of natural gas. Various methods of generating H2 gas from a much denser hydrogen store - such as water - are suggested: heating it up to 3000C (~5400F) using solar collectors or nuclear power, bacterial processes, and catalysts (see figure 2 in the article - looks fancy doesn't it?).

    So, OK, some of the style of the article feels bad to me, but there is some useful physics in there.

  • Distribution strategy?!? (Score:3, Insightful)

    by bradbury ( 33372 ) <Robert DOT Bradbury AT gmail DOT com> on Tuesday January 04, 2005 @09:31PM (#11260048) Homepage
    Ok, hydrogen is a reasonable energy resource. Can someone *please* show me a reasonable distribution strategy? You are talking rebuilding the natural gas pipeline system which the last article I read on that was $100B plus (where is the market that justifies that???). Or we have to have cryogenic fuel tankers with LH2 traveling all around the country. Ok, good idea if they turn over in an environment such as we saw recently in the midwest. Burning LH2 can provide heat for those poor isolated citizens who would otherwise be freezing.

    I do not mean by this message to imply that we cannot move to an economy that oxidizes hydrogen as a primary resource. I *am* intending by this message to point out the amount of hand waving that is going on both within government circles, the Department of Energy, the news media, etc. about the "famed" hydrogen economy. It is a much more difficult problem than the people waving their hands would like us to believe.

    In contrast an energy solution built upon methane (natural gas) which is manufactured from carbon which is in the atmosphere (rather than in the ground) is a viable sustainable solution give technologies and infrastructure we already have.

    We just have to be intelligent enough to (a) develop the organisms to produce the methane; and (b) channel said methane into the existiing natural gas pipeline system; and (c) perhaps develop some incentives that would bias farmers to produce solar ponds that produce methane instead of cows that produce methane. (Think about this for a second -- sunlight provides energy. Photosynthesis grows grass. Cows eat grass. Cows produce methane. Humans consume methane (but it is mostly methane we haul out of the ground that was manufactured thousands of years ago.)

    Are we not clever enough to produce our own methane from atmospheric carbon dioxide in a way that creates a completely sustainable energy system?

    This I ask you...

    And by the way the complete genomes for bacteria that can (a) perform photosynthesis and so are able to harvest solar energy; and (b) the bacteria that can synthesize methane; are in the public databases. They are free for the taking. It will not be easy to merge them. I have some ideas as to how to do this. The point of this message however is to get you to *THINK* outside of the box.

    Yes, we may get some subset of a hydrogen economy. But as most /. readers are probably good engineers you should be asking how, where and when. In the meantime a methane economy could more easily be developed and sustained (i.e. the carbon we put into the atmosphere is carbon we have previously taken out of the atmosphere).

    Just a few thoughts...

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