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As for seawater extraction - where did that paticular gem come from and did the guy have more than an MBA?

1.21GW? Pah. They're producing equipment around the world now that uses 100,000 times that much energy.

http://www.jaeri.go.jp/english/press/980618/gif/te ra01.gif

While you had Google running why not look for this page? It looks like extraction of uranium from sea water may not be the pipe dream you imply it must be. I will have to thank you for one discovery. I had read this stuff from Bernard Cohen some time ago and casually associated the name with the Harvard professor whose books I had read as a juvenile. Turns out there is more than one Bernard Cohen who is a science professor. This one is a professor of physics at Pittsburgh University. Nothing wrong with that since, as you correctly assert, what matters are the numbers.

One of the issues usually absent from most discussions of nuclear energy is the stark difference in scale between it and other technologies like fossil fuel. The mammoth size of nuclear reactors with their containment vessels produce a different impression. I still remember an interview of Freeman Dyson by Dick Cavett who asked whether Dyson would prefer to live near a traditional or nuclear power plant with a clear expectation of what his answer would be. When Dyson immediately indicated a preference for the nuclear option you could watch Cavett's jaw drop. Dyson explained the issue of scale and similar considerations but it is doubtful it made much of an impression since it was so counter to the received wisdom which has lead to the carbon disaster we are facing.

That difference in scale is an important part of why the numbers so starkly favor nuclear technology as a sustainable technology. We have dithered for far too long already trying to live in the make believe world of anti-nuclear fanatics. Of course some have belatedly seen the damage that has been incurred and have changed their tune. But it was their near religious anti-nuclear fervor that resulted in the policies that have presented us with such unpleasant prospects and options. Maybe our ability to innovate and improve technology is not up to the task of making nuclear technology replace out dependence on fossil fuel. If not then in some sense we are doomed. But at least we need to try.

http://www.jaeri.go.jp/english/press/980624/supp.h tml

That site has a little info on solid oxygen. I dont think your going to get the chance to play with it though... It forms a solid under 1/2 million atmospheres of pressure. I do think that if you quickly move it from the pressure chamber to our atmosphere that it would violently decompress and oxidize everything around it.

It it worth noting that the progress made in fusion research has been HUGE throughout the past 3-4 decades and while the next step is more difficult than the last we aew still making steady progress. JT-60 HAS attained a confinement quality in the deuterium-deuterium shots it has taken which are VERY good, so good that if they were done with deuterium-tritium mix they would firmly place JT-60 in the breakeven parameter space very near the ignition regime (they have not "gone DT" due to pain in the ass handling issues with the radioactive tritium). There is also always hope for a shocking surprise breakthrough too (but don't hold your breath). For example, 10 or so years ago, it was though there was no way you could get around having to build immensely expensive multi-hundred beam multi-MEGAjoule laser systems in order to make inertial confinement fusion work. Then along comes a cute little trick called Chirped pulse amplification and suddenly you can start talking about petawatt lasers being used to reduce the overall cost of the machine by 10 fold (fast ignition fusion schemes! That's why science is so great, there is always hope something better is just around the corner waiting to be discovered.

Except that the worst estimates say that if we switched over to 100% nuclear today, we'd have about 100 years of fuel for the most basic power plants.

The cost of uranium is a very small part of the cost of running a nuclear plant. So we can afford to use exotic and expensive mining methods.

So for example we can use Uranium recovery from seawater, which has been demonstrated. There are huge amounts of uranium in seawater. Combine that with reprocessing, and the problem i solved.

Except that the worst estimates say that if we switched over to 100% nuclear today, we'd have about 100 years of fuel for the most basic power plants.

At, and here's an important bit, present fuel costs.

As fuel costs increase, reserves go up, because stuff that wasn't worth exploiting before now is. Fuel costs don't even have to increase too much before uranium extraction from seawater becomes economical, to about $400/lb. The amount of uranium in the oceans at this moment is enough to power the entire world's current energy demand for 7 million years, about 5E9 tons of the stuff.

There's enough uranium around that by the time we run out of it, we'll be able to construct large-scale solar power satellites and ginormous groundside microwave rectennas. And we don't have to confine ourselves to uranium; there's even more thorium around than uranium, and while that won't sustain a chain reaction, it'll fission just fine in an energy amplifier, and you can breed more fissile fuel in the process.

It's doubtful that we'll ever get fusion working, but there's so much fission fuel around capable of driving one plant design or another that if we haven't figured out solar collection satellites by the time we start feeling the pinch of running out of it, we'll deserve to go extinct.

Details.

"He comments that lasting 5 billion years, i.e. longer than the sun will support life on earth, should cause uranium to be considered a renewable resource."

Uranium recovery from seawater.

http://www.jaeri.go.jp/english/ff/ff43/topics.html

The puter will be used for nuclear research (bushspeak: nucjular reesatch) by the Japan Atomic Energy Research Institute. More info about the organisation, their projects, etc. can be found at: http://www.jaeri.go.jp/english/index.cgi.

From reading the press release from 1998, it sounds like they defined the break-even condition as when the output power from the plasma exceeds the power input required to form the plasma. However, one generally would like to keep the plasma confined, and that also requires input power, so while they may have exceeded plasma break-even, they might not have exceeded overall break-even, which is a necessity for a viable power plant.

Last time I checked, Canada, Russia and China preferred the Japanese site.

• EU (28%)
• Japan (28%)
• Russia (14%)
• USA (10%)
• China (10%)
• South-Korea (10%)

I had thought that the international community was hesitant to build ITER in Japan because of earthquakes. But, I found this article that seems to say that earquakes will not be a problem for this cite, for anyone who is interested.

...the Chart of the Nuclides .

More specifically, you mean to write:

(1) H-2 + H-2 -> He-4 + gammas

Or,

(2) H-2 + gamma -> H-1 + n (We'll ignore the electrons)

And the alternate one you discuss is either:

(3) H-2 + H-2 -> He-3 + n + gamma

or

(4) H-2 + H-3 -> He-4 + n + gamma

(I believe this is the one the tokamak project is using. I'm inevitably wrong on this.)

His reaction, from the article description, is probably:

(5) H-1 + H-2 -> H-1 + H-1 + n

I have no evidence to back this up, other than the fact that they never spoke of Helium really being produced, and the lack of tritium in the discussions. By the way, we can also do a some calculations, to determine the Q-value of these reactions: (using This chart of the Nuclides Table .)

Q=(m_init-m_final)c^2 =>

(5) Q= -2.2 MeV In other words, These ionized atoms would have to be travelling quite fast. (It is endothermic after all.)

What about the ones that release energy? How fast do they have to be moving?

Well, from this page we're talking the temperature would have to be between 4 x 10^7 and 4 x 10^8 K, which is kinda hot. You may be able to make a lot of assumptions about the occasional fast moving particle using temperature distribution graphs.

Breeders produce a lot.

The "waste" which is U-235 depleted but plutonium enriched must be further processed to produce weapons-grade material.

This is all-important for making a bomb. U-235 has a half-life of around 700 million years, and making a bomb with it is easy: squeeze together a prompt-supercritical mass, and wait a few milliseconds. Pu-239 is tricky, because its half-life is only about 25000 years and you have very little time to get it into a prompt-supercritical configuration before a spontaneous fission starts the reaction going. If the reaction starts too soon, the bomb blows itself apart into a sub-critical configuration before releasing much energy and all you have is a fizzle. Now imagine dealing with a substantial fraction of Pu-240 (half-life 6564 years or Pu-241 (half-life 14 years).

Bomb-grade material is made in special reactors which allow the fuel to be irradiated relatively briefly at a low level, and then removed and processed to remove the plutonium. This is specifically to avoid the production of enough higher isotopes of plutonium to be a problem. The stuff coming out of a power reactor after a full fuel cycle is dirty as hell, but amateur proliferators are not going to be able to make a serious bomb (as opposed to dirty weapon) out of it. This is why we had few objections to building pressurized-water reactors for North Korea; they are essentially proliferation-proof.

For 25 years we have banned reprocessing even to the level needed for use as fuel because of the concern is could be stolen and further enriched.

I think we should have gone with the Integral Fast Reactor, but it seems to have succumbed to the fundamentalist anti-nukes (who probably couldn't figure out that there are medical and explosive grades of nitroglycerine either...).

Breeders produce a lot.

The "waste" which is U-235 depleted but plutonium enriched must be further processed to produce weapons-grade material.

This is all-important for making a bomb. U-235 has a half-life of around 700 million years, and making a bomb with it is easy: squeeze together a prompt-supercritical mass, and wait a few milliseconds. Pu-239 is tricky, because its half-life is only about 25000 years and you have very little time to get it into a prompt-supercritical configuration before a spontaneous fission starts the reaction going. If the reaction starts too soon, the bomb blows itself apart into a sub-critical configuration before releasing much energy and all you have is a fizzle. Now imagine dealing with a substantial fraction of Pu-240 (half-life 6564 years or Pu-241 (half-life 14 years).

Bomb-grade material is made in special reactors which allow the fuel to be irradiated relatively briefly at a low level, and then removed and processed to remove the plutonium. This is specifically to avoid the production of enough higher isotopes of plutonium to be a problem. The stuff coming out of a power reactor after a full fuel cycle is dirty as hell, but amateur proliferators are not going to be able to make a serious bomb (as opposed to dirty weapon) out of it. This is why we had few objections to building pressurized-water reactors for North Korea; they are essentially proliferation-proof.

For 25 years we have banned reprocessing even to the level needed for use as fuel because of the concern is could be stolen and further enriched.

I think we should have gone with the Integral Fast Reactor, but it seems to have succumbed to the fundamentalist anti-nukes (who probably couldn't figure out that there are medical and explosive grades of nitroglycerine either...).

One thing that hydrogen enthusiasts often seem not to know is that hydrogen is already produced on a large scale, a megatonne or two annually in North America, from fossil fuels.

Nor is a hydrogen infrastructure absent. There are lH2 tanker trucks. Not enough of them, of course, to support tens of millions of hydrogen cars.

Abundantly enough, though, to support the number of such cars that that deep-pocketed clean-motoring enthusiasts, not affiliated with government nor with a car company's research division, have insisted on pioneering. (To the best of my knowledge, that number is holding steady at zero.)

And hydrogen cars, too, exist and have existed for many years (http://www.hydrogen.org/h2cars/overview/cardata/6 7.html, http://www.hydrogen.org/h2cars/overview/cardata/78 . tm).

This makes greenie hydrogen enthusiasts' position seem to boil down to, "Nothing's missing but much higher-priced hydrogen."

A more respectable sort of hydrogen advocate, indeed almost as good as me, since I once was so, is the kind that expect cheaper-than-fossil-derived hydrogen to be made using nuclear thermal methods such as this: http://inisjp.tokai.jaeri.go.jp/ACT00E/09/0903.htm

Direct thermal production of H2 from water has been tried. Rather than losing much of the heat making electricity, and much of the electricity making H2, lose only one much

But water is the wrong oxide to crack. Virtually zero-emission central station energy production has been demonstrated, and so has virtually zero-emission vehicle energy. So I think the important distinction is between zero-local-emission vehicle energy that people will voluntarily buy, because it rivals or beats gasoline's space efficiency, and bulky energy that they won't. Here are some alternative-fuel authorities saying alternative fuel is inevitably bulky, so you should just get over it. I can't.

The Japanese are carrying out an insanely ambitious project,for a 640 node, 40 sustained TeraFlops computer, housed in a building the size of a large hockey arena. They call it the "Earth Simulator" and its main purpose is to carry out atmospheric/climatological research and simulations of the simmering ball of lava we live on (volcano and earthquake research).

Construction is in full swing now; hardware to come online first quarter 2001, software "will take a little longer".

More tech-oriented info here.