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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.)"
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.
"let them"?
When did we become their mommy and daddy?
It's science, and something like this would undoubtabley be monitored and studied world-wide. They can't exactly just sneak around with it, and vaporize L.A.
If we were doing this, you wouldn't want Japan contimplating "letting us".
http://wsulug.org
Look, due to the laws of thermodynamics it will ALWAYS take more energy to obtain a resource than to use it.
So since his lasers are powered by the sun, you are saying that he is not going to produce enough energy to renew the sun?? Damn, I guess this isn't going to work.
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.
Well since Japan has virtually no natural resources, and is therefore even more dependant on foreign sources for energy. I think it is likely that Japan will be the first to break the ties with the oil cartels. They have the lowest concentration of automobiles of any first world country, so most likely to use alternative fuels for public transportation. The also DO have technology and ready access to water (island nation remember). I would think that if the worlds second largest economy could break itself of one major foreign dependence, they will at least try, especially since that coutry is extremely xenophobic.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
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.
Sigh. It does NOT currently take more energy to obtain a Oil than to use it. We aren't out of it. That is why renewable energy sources have such a hard time being competitive. It's hard to beat a dense source of energy that's lying around.
a lot of these arguments against renewable energy sources are just rubbish.
Arguements shmarguements. There will be a massive switchover to renewables when the tech improves enough to make it as cheap as oil, or when we start to run out of oil.
Until then, ranting about social change is nothing more than another source of greenhouse gas.
Anyone who's played Civ or MOO etc, knows the way to win the game is to maximize research.
(And to save umpteen people from replying to point out that I just suggested people base national / global policy in a video game, yeah yeah, I know. I still think it's a valid point.)
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- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
Let's see 504 billion killowatt hours needed.
Each laser is capable of 10 megawatt hours.
Someone correct my math because that leads me
to conclude that we need 50 million orbiting
lasers...
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.
Those lasers won't be very easy to defend, unlike oilfields and power stations. Well, ok, you can drop a few nukes to take out the powerstations but the country woulnd't be habitable afterwards.
It seems to me that relying on this tech for power makes you a hell of a lot more vunerable.
And the people shall be oppressed, every one by another, and every one by his neighbour Isaiah 3:5
Actually, that isn't the problem with Hydrogen.
The problem with Hydrogen is that to make it, the process is only 20% efficient. This compares unfavourably with other processes, e.g. batteries are more like 50% efficient. Still, if you have a pollution free, inexaustable source of energy ('the Sun') this doesn't matter as much.
The other problem with Hydrogen is its low density. This can be improved by compressing it or storing it in a metal 'catalyst', but then it stops being low density and becomes rather too heavy for cars and such like.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"The poster is guity only of imprecise phrasing. It should've reflected the costs of such conversions. Right now, it costs more to create hydrogen than the income converting the hydrogen to energy would create. A hydrogen-based economy doesn't exist because of the costs involved, not the physics behind it.
The problem is that they aren't that effective. The turnaround time from intel collection to a conventional bombing run is usally far too long. You need to have bombers in the area, bombs in the arsenal, and generally have a static target that won't move from the time of intel collection to bomb run; generally pointless for taking out personnel; much more effective for equipment. With a space based weapon system (such as lasers), you could more or less pin-point any area under the satellite within a few momements of getting the intel. Throw enough of them above the earth in a geo-synchronous orbit and you could cover all the inhabited portions of the planet. Yes, yes, I'm completing ignoring the political ramifications of a space based assassination system. Remember Real Genius? Well, the movie was quite fantastical, but the theory is sound. Two years ago, a predator drone had a live video feed of Bin Laden in a training camp, sadly they were unarmed and could do nothing but watch him wander about. Any wonder why they are all armed now?
there are no stupid questions, but there are a lot of inquisitive idiots
So renewable energy sources will always require more energy to be put into them than you get back out. But in that case, it doesn't matter, does it? We use such an insignificantly tiny amount of the energy coming off the sun that throwing some more solar collectors into orbit isn't going to negatively effect our current thermodynamic economy in any appreciable way whatsoever. Now, if we'd built a big ol' whopping dyson sphere around the sun collecting 100% of its energy, the shadow cast by the satellite would cause an actual energy trade-off... a negative one, due to the energy lost in firing that big ol' laser and everything. But, um, we don't have a big ol' whopping dyson sphere. We're just tapping into an energy source we're using pathetically little of right now. So, screw thermodynamics. :D
At some point....we will have to learn to live with the fact that there will be many (at least more than 2) organazations that can kill millions of people anywhere at anytime. The technology is within grasp and so we know that if it is within grasp we will grab it. The delema will not be "how do avoid this technology getting into the wrong hands" it will be "how do we as humans overcome our instinct to kill each other and assert control over one another?"
Maybe I'm crazy, but it seems to me that instead of a Buck Rogers-style solution to cracking H2O into H2, why not use fission power to do the same thing? Fission power is a well-known source of energy - no R&D involved - and the plants used to crack H2O into H2 can be located far from any populated area, to minimize risk in case of an accident. A question for the chemists in the /. audience: would it be feasible to use fission power to combine atmospheric CO2 with H2O to make methane? If so, it would be possible to port the methane via the nation's natural-gas pipelines to power home fuel-cell units to generate electricity. In effect, you could transmit nuclear-generated energy thousands of miles with minimal transmission loss. Just a thought.
In any event, I was delighted to read about the fuel-cell initiative. I'll be buying one of those home units as soon I can afford one.
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Also, consider this: If one automobile company realizes that by making its cars dependent on a foreign, expensive substance (like oil), it's crippling itself. Imagine that this field of study comes to fruition and this Mitsubishi-sponsored technology begins pumping out hydrogen. All Mitsubish has to do then is build a car that will safely run on hyrdrogen and suddenly, they've got a perfectly good machine to which they control the source of fuel. Granted, they can't make a killing off of this right off, because they have to undercut the oil companies, but so long as they're making a profit, they can continue to do this. If it's cheaper to use hydrogen, then people will and this will spur a change in the economy/infrastructure as oil-dependent companies realize they're being outsold by a cheaper, cleaner solution. Mind, Mitsubishi's motive isn't change. It's the returns they'll make while everybody else is retooling to use hydrogen. Not to mention that it gives them that much longer to advance their technology ahead of the competition.
Virtue finds and chooses the mean.
Aristotle, Ethica Nichomachea