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Orbiting Lasers for Hydrogen Power
DerekLyons writes: "Yahoo is carrying a story about a Japanese scientist who plans to use giant orbiting lasers to extract H2 from seawater. The interesting part of the scheme is that design uses solar pumped lasers, which avoid the loss of efficiency (and increased launch weight) from powering the laser with electricity from solar cells. Is the way to finally break the main dilemma of the hydrogen economy? (That it takes more energy to make the hydrogen than you gain in using it.)"
I predict that within 30 minutes, there will be at least two confused posts saying that we should just use solar panels to generate electricity to "crack" the hydrogen from sea water.
I further predict that at least one of these will, after someone posts a brief reply explaining why that's not a workable idea, dissolve into flames.
Any government or corporation that puts anything into orbit that could even potentially be used as a weapon is going to face resistance from the entire world. Even if you went into contortions trying to prove that the tool could never be used for military purposes, the media would get ahold of the term "space lasers" and that would be curtains for the idea.
"That it takes more energy to make the hydrogen than you gain in using it."
Look, due to the laws of thermodynamics it will ALWAYS take more energy to obtain a resource than to use it. Same applies for oil - once we're out of it, it will be very damn expensive to "make" it. So a lot of these arguments against renewable energy sources are just rubbish. Sure, you don't get as big of an *immediate* payoff, but you get a much steadier, reliable payoff over time. The trick is amortizing the expense of using a certain fuel by using the byproducts in a very efficient way. We waste such vast amounts of energy both in direct use, and in unrecaptured efficiency, that I'm sure any number of energy sources will be totally viable (hydrogen, wind, solar, thermal, hydro, methane). But of course many of these will require social changes that nobody is willing to make. To paraphrase Denis Leary, everybody wants to get themselves a 1967 Cadillac El Dorado convertible, hot pink with whaleskin hub caps and all leather cow interior and big brown baby seal eyes for headlights, drive around in that baby at 115mph getting one mile per gallon, sucking down quarter pounder cheese burgers from McDonald's in the old-fashioned non-biodegradable styrofoam containers and when they're done sucking down those grease ball burgers, wipe their mouths with the American flag and toss the styrofoam container right out the side and there ain't a God damned thing anybody can do about it.
It's 10 PM. Do you know if you're un-American?
All known solid state laser gain substances have fairly narrowband excitation spectrums. This presents a two fold problem: 1) fairly little power is available in that window (the sun is a blackbody raditator) 2) Energy outside of that window tends to just heat the medium and either cause breakdown or unacceptable thermal lensing.
I've built a solar pumped nd:yvo4 laser, but it was a waste: because of those factors I could have extracted more power and probably energy from a solar electric system.
Without some serious new developments in laser substances with ultra broadband pump inputs, this won't work too well.
Ok Im not a tree hugger, BUT what are the long term effects say on the Ozone of pumping a laser of this magnitude though the atmosphere not to mention ionizing radiation effects while it travels through the air ?
:)
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My understanding is it REQUIES VERY HIGH temperatures to Dissacociate water on the order of 3500 degreesf plus (PS Dont ever try to quelch a thermite reaction with water
Ok so were using Ti02 as a catalyst, what my question is what about thermal evnviormental pollution, hell in some cases its worse than chemical pollution. Hmm were encountering a greenhouse effect globally lets fire oh say 50 or so 10+ megawat lasers at earth. (Its only one until it works)
If this is going to be succesfull youll see a commercial proliferation of these without regard for saftey, No dont think so , look at the oil companies and their rigs , then consider again when Oil companies see this as the next big thing ?
Hell with all that free hydrogen you could manufacture your own hydrocarbons CHEAP, aka GAS
Nice big vicious cycle Gotta Love Science
Sig went tro...aahemmm.....fishing........
Unlike in the States, big compaines in Japan have a little bit of everything. Mitsubishi makes cars, trains, ships, aircraft, televisions, stereos, agricultural chemicals, food additives, synthetic rubber, molasses, canned foods, textiles, semiconductors ... the list goes on. Any large project in Japan couldn't avoid being associated with a company that also makes cars.
Toronto-area transit rider? Rate your ride.
One problem when comparing plans like this for producing fuel, to other more traditional fuels is that the cost of crude oil or whatever does not reflect the value of the oil.
That is if we had to reproduce the oil rather than just extracting it from the ground we'd probably find other more "green" methods of energy production much less of an investment.
The fact that something that is renewable cost more than something that is irreplaceable is a pointer to the shortcomings of our economic system, not to problems with solar, wind, or other alternative energy sources.
A weapon system that's PROFITABLE when not in use! Just imagine how the economic numbers on this thing look better if the DOD covers, say 25% of operating costs for the right to commender it during wartime.
A giant orbital laser that fires to the ground into a giant salt water swimmingpool.
What is the impact of fried birds dropping onto this pool?
What can this concentrated energy do to some of the earths outer layers that are important for climate? Atmosphere, stratosphere, and so on.
Impact on the ozone layer, which is already (by definition, not by human interaction) quite thin and easy to disturb?
What are they going to do with all the Oxygenium? Since the air we breathe consists to more than 70 percent of Nitrogen, not Oxygene, simply freeing large volumes could be problematic. (And can be quite a risk for the installation itself. Think of "no smoking".)
What if a mislead plane happens to fly into the beam? A weather balloon?
Impact on clouds? Hitting them (and the H2O within them) will also split the H2O, and then Ozone will react from the Oxygenium radicals. And: Ozone is only good in exactly the right height over ground. Every Ozone lower than that is poisonous and, in the volumes we're talking about, could lead to quite interesting weather effects within these clouds.
Don't talk about what happens if this cloud of ozone happens to drift over some city. In cities, we usually call this "smog" and try to avoid it.
Sulfur dioxide, raising up in clouds from big cities or other things that burn fuel (oil plants?) is known to react to Sulfur Acid in the athmospere, with the help of the power of sunlight. A while after, we call this "sour rain" or "acid rain". What amount of acid could react if a cloud like this is hit by this _very_ strong artificial sun?
Nice idea, but done by company scientists for company scientists. IMHO, this could cause far too many things to be implemented.
And, remember: "They" are not fiddling with a x square miles big sector of air above their installation. They're fiddling with the atmosphere that is shared by some billion of people. There is hardly a thing like local effects with wind, clouds, and weather. Ask your European friend if he sometimes finds a thin layer of very fine sand outside his house or on his windows. This comes straight from the Sahara desert in Africa. (No, I'm not kidding.)
When the reactor in Tchernobyl went "blob", the radioactive dirt was distributed over half of Europe, 1000s of kilometres, which still ended up with enough dirt to have them throw away every vegetable in their gardens.
And: Science doesn't have any data about what happens to the very highest layers above us when hit by a concentrated stream of energy on a single point that is several times stronger than the strong rays of the real sun around it. It might well cause something or, doing this several months in a row, burn a hole into a layer of gases that we not even know about yet. We Just Don't Know.
Fiddling with this is just stupid.
42. Easy. What is 32 + 8 + 2?
... the Alan Parsons project.
Karma: Professionally Doomed (mostly affected by inability to keep opinions to self)
C'mon people! All I want is some frickin' sharks with lasers on their heads! Is that too much to ask?
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Gort! Klatu Barata Nikto!
Sorry, but you managed to be substantially wrong in parts of BOTH of your points :-)
not to mention the industry mogul's vested interest
You keep hearing this ridiculous statement from people, and I don't understand how people think a future hydrogen economy would be any different. If and when we move to a hydrogen based energy economy, who do you think will be the ones extracting, storing, shipping, and selling the hydrogen? I'll give you one guess... the current players that dominate the petroleum/coal based energy economy. They're the ones that have the capital to make it happen.
Incidentally, the energy industry would LOVE to be able to natively produce hydrogen, and be paid for creation, distribution, and sale; they would drop oil in a heartbeat if they could, because there would be more profit at a lower cost, and that is always a win. There is VASTLY more uncertainty in doing business in the parts of the world that have the most oil than it is to do business in the first world, and that drives up costs tremendously. There are huge expenses in extraction, transportation, storage, refinement, bribes, legal issues, and taxation that just would not be encountered if they could do all of these things at home. And let's not forget that they would score a big PR win for their support of the "environment" (no more "pollution", no more spills, no more ground water contamination, etc...). There is no upside to "protecting" oil once the technology is there to produce/store/transport hydrogen cheaply.
there are always energy costs to creating portable forms of energy, but that's the issue, not that it's more energy-expensive to create hydrogen than to use it.
No, that really isn't the point. The point the previous poster was trying to make is that the energy cost of extracting, processing, shipping, and selling petroleum based products is substantially LOWER than the amount of energy extracted from the oil. This is because the energy has already been stored for us, for free, in the oil; burning the oil releases the stored energy, and digging it up costs almost nothing energy-wise. For hydrogen, however, there is no such "free store" we can dig up. Combine hydrogen with oxygen to get water, and you get a relatively huge release of energy, but we have no previously STORED source of hydrogen; we have to disassemble water to get that hydrogen. But, the energy cost of cracking water is substantially HIGHER than the amount of energy that can later be extracted from the stored hydrogen. So, there is currently no feasible way to phase out our use of petroleum; in fact, if we switched to hydrogen power in our cars today, it would drive UP the demand for oil, not decrease it (a similar problem would occur if we all went out and switched to electric cars today). The real benefit of oil is not its portability; the real benefit is that it stores vastly more chemical energy than it takes to extract it from the ground.
The main problem of all renewable energy schemes is that fossil fuels are formed by millions of years of solar energy accumulated by the biosphere and millions of years of geological pressure. It isn't that these fuels are more fundamentally efficient - in fact, they are relatively innefficient from many perspectives. It is that nature has done all the work for us - leaving us to liberate the value at our leisure. Convenient, and in the extremely narrow and short-sighted view we've taken of energy, cheap.
The problems, of course, are that we are stuck with relatively dirty fuels like coal and oil, and that these fuels are not renewable in the short term. Hence, any renewable fuel will face us with a cost-benefits problem: it will cost more to produce than an equivalent unit of coal or oil. Until we start measuring the environmental, political and future stability/planning impacts as part of the cost of burning fossil fuels, it will always seem economically preferable to stick with our old standbys.
The real issue of hydrogen or any alternative fuels (biomass derived, ethanol, etc.) is to find the most efficient way to use a renewable or sustainable energy source. Hydrogen has the convenience and benefit of being a fuel: useful from points of view of storage and self-containment.
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