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The Physics of the Hydrogen Economy
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."
This looks like something I read in January's Popular Science last week!
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.
'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
94% of Repubs and 21% of Dems voted to renew the Patriot Act
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.
Hydrogen is an integral component of dihydrogen monoxide
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.
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...
The Spoon
Updated 6/28/2011
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"...
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.
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, is no longer with the DOE.
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.
"We tend to become like the worst in those we oppose." "Perceptions rule the universe." --Bene Gesserit Sayings
I should know, I never could get work as a physicist:-( There are other analyses 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.
SLASHDOT: news for people who can't concentrate on work or have no life at all and got tired of yelling back at the TV.
It's not just moving pollution around, it's more about changing the *type* of pollution. You can produce Hydrogen with nuclear power or renewable energy source, which both (debatable of course) are far safer that burning fossil fuels (which cause acid rain, CO2 emissions, Middle East wars...) to get equal amount of energy.
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?
love is just extroverted narcissism
"Moving the pollution around" isn't necessarily a bad thing. If you move the source of pollution from millions of loosely regulated and privately owned vehicles and transfer it to relatively small number of well regulated hydrogen processing plants, the net effect will still be positive.
Reducing emissions as new technology comes about will entail upgrading those processing plants rather than trying to get millions of drivers to upgrade their vehicle.
"People that quote themselves in their signatures bother me" - athakur999
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.
[Sir Garlon] is the marvellest knight that is now living, for he destroyeth many good knights, for he goeth invisible.
Exactly.
BUT lets say we're talking about powering cars with Hydrogen. Now you've moved the pollution from hundreds of thousands of cars to several dozen power plants/watercrackers.
Now, tell me you can afford a $5k exhaust scrubber for your car's exhaust? No? Well, a powerplant running 500k cars should be able to afford a larger $100k scrubber.
By bringing pollution to a single point, that pollution becomes easier to measure as well as manage.
If I have been able to see further than others, it is because I bought a pair of binoculars.
Hydrogen is a Boondoggle. 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 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.)
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.
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:
Energy: time to change the picture.
Every technology has its unexpected negative consequences.
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
Shoes for Industry. Shoes for the Dead.
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.
This comment does not represent the views or opinions of the user.
When you burn gasoline in a power plant, you run at one speed, the most efficient one. This means that a gallon of gas burned in a power plant will generally speaking cause less pollution than a gallon of gas burned in an automobile.
The upshot of this is that even if all of the hydrogen used in automobiles were created in power plants fueled with gasoline, there'd still be a huge reduction in the amount of pollution emitted.
This is not even getting into the fact that it is easier to create technologies to trap polluting emissions in a few power plants than a million cars.
As a thought experiment, imagine if instead of having coal fire plants generate electricity, we just put coal-based generators in everyone's house. Do you think the amount of overall pollution would be the same? After all, the electricity is just "moving around" where the coal is burned.
The final reason that this is important is that it is much easier to add new alternative fuel power plant online than it is to create an alternative fuel car. Right now, there is absolutely no way to make a car run on solar power, period. If, however, there were large numbers of hydrogen powered cars around on the road today, you could move toward non-polluting sources simply by putting a solar power plant on the grid.
So no, a hydrogen economy is not perfect. However, it is better than what we've got. It's also a first step towards an economy that doesn't use fossil fuels.
The cake is a pie
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.
Proud member of the Weirdo-American community.
How does this alleviate global warming? Does biodiesel not release carbon dioxide when it burns?
Of course it does, but its creation consumes as much.
OK Since I'm the one who submitted the article, please allow me to clarify some logical errors in your statements.
,insert the electrodes, add some acid as catalyst, and plug the wires into a battery. Voila! Oxygen in one, hydrogen in the other. Now Try making oil from wood with your chemistry kit.
So, in order to have a large-scale hydrogen "economy", you need an alternate power source to make all that hydrogen in the first place.
News for you. Hydrogen is not "made". It's extracted. OK, putting the word jokes aside, I understand that what you mean is that *PURE* hydrogen is not found *NATURALLY* on Earth.
So we need an ALTERNATIVE power source to obtain it. So what? Electricity is not energy either! It's a bunch of electrons and possitive ions waiting for us to mix them together. We use turbines in dams to produce it. (kynetic energy -> electrical energy). We need engines (kynetic->chemical) to take out the oil from the deposits below Earth.
Didn't you study physics in high school? Just climbing some stairs transforms the kinetic energy you use to move, into "potential energy". And by falling you turn it into kinetic energy, too. And guess what, we're made of protons,electrons and neutrons, and all of these are made of quantums, which are discrete packets of *energy*.
EVERYTHING's energy, dude! So what's the mystery if hydrogen needs some alternate energy to be extracted from water or other compounds? Don't forget your thermodynamics lessons from college. All engines do is transforming one form of energy into another. And since no engine is 100% efficient, then we have what is known as "entropy", which constantly is increased across the universe.
So, what power source can we have to extract pure H2 from other materials? Well, we can have, for example, solar power.
Hydrogen can be built *instantly* with some electrolysis (either chemically or solar powered). I did it myself at home when i was a kid. You put these water-filled tubes in a bucket (upside down)
The H2-generating process is sub-optimal right now (as was the vacuum tube in the 70's to act as a current switch), but technology always improves with time. And don't forget that big companies like Shell are investing millions of dollars into research.
The point with using hydrogen, is that:
a) It's combustible and can produce energy when reacting chemically with other elements/compounds.
b) Unlike fossil fuels, it doesn't require millions of years to be produced/extracted/whatever.
c) It's clean, it doesn't produce CO2 when burned.
Did you RTFA by the way? How do you think fossil fuels are made? Plants transformed H2O + CO2 + SOLAR POWER + nutrients into wood (and O2 as a byproduct). And these with time were transformed into hydrocarbons. Which consist of long hydrogen and carbon chains (not to be confused with carbohydrates - sugars -, which have oxygen in them).
The real energy in hydrocarbons is stored in the chemical bonds between the carbon and hydrogen atoms. By burning them, the combustion process releases these bonds. O2 + (long chains of C + H) ---> H2O + CO2. See? There's the hydrogen, and the C. What we're wanting to do, is get the carbon out of the equation. O2 + 2H2 ---> 2 H2O.
So, is hydrogen economy all that far-fetched? No, it isn't! We've been using hydrogen in our cars for a lot of time. The problem is that we're also using carbon.
Frankly, I'm amazed why your post was moderated as "insightful" (someone MOD it as overrated, please!). More mysterious than the universe is the human ignorance.
P.S. If this post is modded up, please do so as "informative".
Well, fossil fuels are pumped from the ground, burned, and the combustion products go into the atmosphere with no way to to be re-fixxed into the underground petrol, thus producing an open loop (bad) Carbon cycle. The combustion products of plant derived fuels are re-fixxed into succeeding generations of plants thus closing the loop (good) with a zero net gain of Carbon into the atmosphere.
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.
-- Old Man Kensey
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.
I'm afraid I've lost a lot of respect for RMI over the past five years. They know the truth about the energy resources situation, but their publications promote soothing, pernicious lies. Organizations that say "We have an energy crisis coming, and the only solution is radical efficiency combined with lifestyle change combined with shrinking the global economy to achieve a gradual Powerdown" get neither grant money nor political support. Organizations that say "We have an energy crisis coming, but our technical fixes will allow the status quo to continue" get both grants and political support. RMI has chosen to say the latter, even though they ought to know better. By promoting a 'technofix' approach and claiming it can solve the impending energy crisis (it can not), they do us all a grave dis-service. If one carefully examines the numbers regarding viable future energy use, the realworld choices become quite clear. The single biggest step our species MUST take, that hardly anyone is even willing to discuss, is removing cars from cities. I personally believe that any city which has not converted to a mostly carfree model by about 2020 will cease to function as a city. About 30% of the global energy budget is spent on moving big chunks of steel and small people around our cities. See http://www.carfree.com for a detailed and attractive explanation of why carfree cities would inprove urban quality of life while using drastically less energy. I hope we eventually all realize that it's how we should have done things in the first place.
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.
This is not a sig
In fact, its creation consumes *exactly* as much as will be liberated by burning it. The reason that burning oil creates a greenhouse gas issue is that the CO2 that is released from the reaction was sealed away millions of years ago, so the net free gas goes up. With algae, you're releasing CO2 that was just removed from the atmosphere a few weeks/months earlier, so the net free CO2 stays level.
"Because Science" is one step from "Because old book". Try "Because of my experiment testing my falsifiable assertion".
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...
While this reply is off-topic in regards to the story, I feel there is some stuff that should corrected.
The recurrence interval for large scale eruptions at Yellowstone ranges from 600Ka to 800Ka. That's a 200,000 year range. The last major eruption was ~640Ka ago.
That means it might erupt tomorrow, or it might erupt 120,000 years from now. Chances are, we won't be alive to see it when it finally happens.
It's also entirely possible that it might not have a major eruption ever again. The 600-800Ka recurrence intervals are based on only three large eruption events that have occured in the past 2 million years.
Currently, seismicity in the region is at relatively low background levels and there really isn't anything to worry about. We see the same sort of situation at Long Valley Caldera as well.
Regarding the grandparent's theory of how to use geothermal power: I have to say that I disagree with it. Just because there is magma down there doesn't mean it will be economically feasible to drill through the rock that the plant will sit on.
As the parent poster states, there are also possible drawbacks and consequences as well. It has been proven that earthquakes in The Geysers region of California (northwest of San Francisco) are caused by the injection of water into the ground. Whether this could lead to some bigger event in certain areas, we don't know.
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 cover the cost.
Then, you would have the fun time period in-between the completion of this new magical rail system where you would still need roads. So, somehow you need to build this track system while still preserving the road system. This is an completely unthinkable task unless you commit yourself to some serious private land seizures. If you want to make a new rail system appear out of air and not destroy the existing road system until it is done, you are going to have to tell people to vacate their house while the government bulldozes it down to make way for the greatest piece of pork ever conceived.
If you are going to cover the entire nation in this thing in one life time, you also will need a massive amount of construction crews and equipment. I don't know about you, but I have no intention of quitting my day job to be a construction worker. That means that the US is going to import a massive number of people to work these jobs and pay them, straight out of the government's pocket. Further, some has to oversee and manage the entire project and keep it on budget.
So, now we have this magical rail system, we need to continue to pay for it. If you thought a layer of tar was expensive - imagine the joys of keeping a magnetic rail system intact. Certainly you could build safety into these things, but if cars are zipping around at a 100+ miles per hour, you better be ready to jump on any repairs that are needed. The materials all costs significantly more then tar does. Further, you need to completely rewire the US power grid. The power grid as its stands couldn't even begin to handle having to support every single personal and commercial vehicle.
So yeah, really cute idea. Alls you need to do is convince people initiate the biggest government project in history, raise taxes as far as they will go, seize millions of acres of private land, some how oversee and manage this project, then once it is done devote massive amounts of government budget to its continual upkeep. No, the "GDP boost alone" will NOT pay for it. This idea is at best a recipe for making an industrialized nation into a poor third world nation, and most likely a recipe for a violent anti-government revolution. Mods, please think before you label this crap interesting. I might as well throw up my "just drive to Mars idea in family mini-van". I mean, it would work perfectly with only the small hitch of a few million miles of vacuum between here and there.
First I want to thank you--that is a useful table!
(How do you prevent slashdot from sticking random spaces into the link?)
But please look at the right column!
in terms of _gravimetric_ density, hydrogen (in any form) beats every other entry handily. 39,000 Watt-hours/kilogram, versus just over a third of that for propane, and only 12,200 for gasoline. Gasoline wins on this table hands down for _volumetric_ efficiency, but you'd be hard put to show from that that carbon bond strength has anything to do with it at all. I think it is a simple matter of the material density. Unfortunately I don't know the chemical formula of propane, but a typical gasoline molecule is made up of roughly 2 hydrogens for every carbon, or maybe a bit less. A benzene ring has 6 and 6 but it is a closed system; to form the more complex hydrocarbons there clearly can be few double bonds involved and lots of hydrogen.
Let's just assume that gasoline is 1.5 hydrogens per carbon, and that how they are bonded to each other doesn't matter much--in the end it all burns to water and CO2. OK? Carbon weighs 12 AMU, plus 1.5 hydrogens gets us 13.5 versus 2 for a hydrogen molecule. Let's multiply the hydrocarbon by 4: we get a segment that weighs 54 with 4 carbons and 6 hydrogens, that consumes 11 oxygen atoms to yield 3 waters and 4 CO2 molecules. This fuel weighed 27 times one hydrogen so we burn 27 kg of it to get 329400 Wh/kg or 8.446 times the heat of burning 1 kg of hydrogen. Now subtract 3 from that output ratio, representing three water molecules, to get 5.446 and divide that by 4; the formation of 1 CO2 by these assumptions releases as much heat as 1.36 water molecules forming. Not a dramatic difference and I rather think that hydrocarbons have more hydrogen than that. Note that propane is more punchy on a mass basis and is a simpler, lighter, more hydrogen-intense molecule. If the hydrogen ratio was as low as 1:1 which I think is impossible for something as volatile as gasoline, forming CO2 would be worth 1.533 water-formations--still pretty lame when you consider that there are 2 oxygen atoms in the reaction! If the ratio is more like 2 H to 1 C, then the output ratio drops to 1.19. Hydrogen-oxygen bonds actually seem pretty strong!
For cars or boats or trains, perhaps this doesn't signify all that much; volumetric density matters a lot. But for aircraft, where saving weight is the name of the game, hydrogen fuel delivers tremendous advantages. Even though the fuel must be stored in very bulky tanks that will cause extra drag and increase structural weight, the savings in fuel weight would be so great that the wings (a major source of drag area!) would be much smaller. If anyone here cared I could go on about how the advantages for airships would be even more decisive.
It is very overblown then to claim that "hydrogen as a fuel is not backed up by the laws of physics." Where weight is important, it is three times better than any other chemical storage medium. This is why it is used in rockets of course. (Higher specific impulse too--but that is also a funtion of its very low mass and high _mass_ energy density!)
Evidently there is not all that much energy in the double bonds of carbon as you think.
Nuclear is NOT an alternative energy source. It is a very dirty and dangerous power source. Anyone that believes that nuclear power is clean, cheap and safe has been brainwashed by the well-funded nuclear industry's public relations arm.
Or are atomic scientists or know enough about the reality, not the hype, or physics in general to know the truth. Physics doesn't lie. Coal plants put more radiation into the environment than nuclear plants. Fact. Even the worst accidents on record are not even a drop in the bucket in comparison to the fatalities caused every year by non-nuclear power generation systems. As of a few years ago, using small scale efforts, over 10% of the contaminated land around Chernobyl has been reclaimed. Mostly through the use of phytoremediation (use plants that naturally decontaminate). Over half of the pre-incident population still lives ther and a large part of the land initially effected has radiation levels that have naturally decreased to the levels needed for producing clean (i.e. radiation free) food, water, and livestock.
"According to the Nuclear Energy Agency (a specialized agency within the Organization for Economic Co-operation and Development, an intergovernmental organization of industrialized countries based in Paris) only 31 persons as of April 2001 had died as a direct consequence of the accident. They were all either plant personnel or directly involved in fighting the fire following the explosion. Another 140 individuals from these same groups suffered varying degrees of radiation sickness and health impairment, but all had recovered fully with no permanent consequences. During the period between 1990 and 1998, in the regions affected by the explosion and subsequent fallout, officials diagnosed 1,791 cases of thyroid cancer that were assumed to have been caused by the radiation release."
-- Robert G. Williscroft of DefenceWatch.
And that's the worst real life actual event for nuclear energy. An event that is physically impossible in American reactor design.
Fact is we, the US, have decades of safe use of nuclear power reactors. Other countries have it as well. Once you get past the hype, you get enlightened.
Anyone who beleives nuclear is this horrible uncontainable monster has been brainwashed by lunatics and anti-reality scaremongers.
Mods: the parent post is not only insightful, it is incorrect. Please act accordingly.
My Suburban burns less gasoline than your Prius.