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Feds Want Nuclear Waste Train, But Don't Know Where It Would Go

brambus Re:Since nuclear is "too cheap to meter"... (156 comments)

I don't honestly give two shits about what somebody on Wikipedia thinks or doesn't think. They could discuss whether the Earth is flat for all I care. I'm merely going with a source that was closest to the original speaker and is thus most qualified (although potentially biased, as you note) to clarify and without evidence to the contrary, I have no reason to disbelieve him. In any case, whatever the specific technology Strauss was envisioning in that short snippet, the fact remains that it was a quote torn wholly out of context in a speech where he was vexing poetically about the potential of scientific ingenuity to address societal ills:

It is not too much to expect that our children will enjoy in their homes electrical energy too cheap to meter; will know of great periodic regional famines in the world only as matters of history; will travel effortlessly over the seas and under them and through the air with a minimum of danger and at great speeds, and will experience a lifespan far longer than ours, as disease yields and man comes to understand what causes him to age. This is the forecast of an age of peace.
New York Times, August 7, 1955

If you wanted to latch on to quote mines you could well say that he was an idiot for thinking that "[his] children" (implying the technology being one generation away) would figure out the source of and be able to prevent aging. Or that air travel would be done "at great speed", whereas it has not in any meaningful way progressed in speed beyond levels attainable in the early 1950s and the only craft that was capable of that was retired with no replacement in sight.
If, however, you include the context and view his statements in light of these clearly farsighted predictions of advances in medical research and transportation, it becomes evident that he was not talking about technology that was just at that time being developed and deployed.

Shills is shills, ya know?

Accusations of shilling are among the lowest form of argumentation. They are the refuge of a man with no evidence to show and no case to present (hence your citing of the talk page to a Wikipedia article - that hallmark of reputable discourse), so all that remains is a tactic of character assassination of the opposition. In any case, irrespective of the material ties of the mentioned Wikipedia editor with the nuclear industry, I did not cite Wikipedia as my source, so your bringing it up in order to highlight a perceived case of conflict of interest is at best a red herring.

7 hours ago
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Feds Want Nuclear Waste Train, But Don't Know Where It Would Go

brambus Re:Since nuclear is "too cheap to meter"... (156 comments)

And one of the ways to start on solving these trivial issues is by stopping this myth of the "too cheap to meter" quote meaning nuclear fission (footnote):

An account of the history of the remark is given in a brief report prepared by the Atomic Industrial Forum (AIF), a nuclear advocacy organization. There is a good chance that Strauss was thinking of fusion power, not fission power, although he could not be explicit because the practicalities of fusion were secret in 1954, with the development of the hydrogen bomb only recently started. The AIF report quotes Lewis H. Strauss, the son of Lewis L. Strauss and himself a physicist: "I would say my father was referring to fusion energy. I know this because I became my father's eyes and ears as I travelled around the country for him."

11 hours ago
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Feds Want Nuclear Waste Train, But Don't Know Where It Would Go

brambus Re:Reprocessing? (156 comments)

That way the 'waste' could be used as fuel with (as far as I know) very little, if any, reprocessing.

Even with modern fast reactor designs running on metallic fuel, some reprocessing is still necessary, though it's nowhere near as involved, messy and proliferation-prone as PUREX and aqueous processes. The most tantalizing prospect for fast reactors running on metallic fuel, especially for systems which incorporate fission product off-gassing and capture while in operation, is the ability to achieve extremely high burn up, which allows this reprocessing step to only be performed at very infrequent intervals (say once every 30-40 years). This means the power plant doesn't need its own attached reprocessing facility (as the IFR project proposed), but instead the investment in the reprocessing facility can be shared, concentrated into a single, well secured and efficient facility for, say, the whole country.

11 hours ago
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New NRC Rule Supports Indefinite Storage of Nuclear Waste

brambus Re:On site transmutation (173 comments)

Stop being philosophical and just give the numbers. We'll discuss after that.

2 days ago
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New NRC Rule Supports Indefinite Storage of Nuclear Waste

brambus Re:On site transmutation (173 comments)

I said pitch your best case and it better be quantitative, not just a bunch of links to some research of other people you just quickly googled that seemed they might address what you want.

2 days ago
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New NRC Rule Supports Indefinite Storage of Nuclear Waste

brambus Re:On site transmutation (173 comments)

Go right ahead. Pitch the best case.

2 days ago
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New NRC Rule Supports Indefinite Storage of Nuclear Waste

brambus Re:On site transmutation (173 comments)

Well, I've tried to make clear that your claims about energy requirements and accelerator size are off, but you won't listen.

Numbers, then we can talk. Beam currents, particle energies, power flows, cooling requirements. Work those out and post them. I'm done with playing nice. Put up or shut up is the motto in science.

2 days ago
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New NRC Rule Supports Indefinite Storage of Nuclear Waste

brambus Re:On site transmutation (173 comments)

I never said heavy ion colliders don't exist, of course they do. The problem is you will never admit even when you are 100% wrong on everything you say, back to front, such as when you don't even understand the energy requirements to do the task you propose, or how you don't even understand the sources you cite. The reason is simple, you have no quantitative understanding of the problem, which is something I often find with renewable advocates.
I'm wasting my time with you here, it'd be more productive to go debate evolution with a creationist.

2 days ago
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New NRC Rule Supports Indefinite Storage of Nuclear Waste

brambus Re:On site transmutation (173 comments)

Before I start addressing your new claims (and there's plenty wrong with even your last post), I want you to admit that you were wrong when you said "the Bevatron could do this", as I clearly showed you it couldn't. If you're not even capable of doing that, then there's no sense in talking to you.

3 days ago
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New NRC Rule Supports Indefinite Storage of Nuclear Waste

brambus Re:On site transmutation (173 comments)

The Bevatron could only muster beam currents of less than 100 microamps, so even assuming every proton disintegrated a target nucleus (which is highly optimistic! I'm ignoring collision cross sections here completely), 1kg of 100-atom mass material contains about 6x10^24 particles, so it would take... over 300 years to completely obliterate. Or 300000 years if we're talking about 1 ton of material. Oh and the Bevatron needed ~100 MW of electrical power to operate, so the cost of operating it for 300 years to burn up 1kg of material... $15 billion dollars at $0.06 per kWh. At that cost we might as well just put on a rocket and blast it out of the Solar system. That only costs ~$30000/kg.
If paying $15 billion for 1 kg of material doesn't sound silly enough to you, I have no words left for you. Heck, you're probably happy if it costs that much, that'll probably just make you think "omg, nuclear power is sooo expensive, lololol" instead of the correct one "holy shit, the idea of accelerator-incineration is astronomically stupid."

3 days ago
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New NRC Rule Supports Indefinite Storage of Nuclear Waste

brambus Re:On site transmutation (173 comments)

I'm talking about particle intensities (measured in amps), not particle energies (measured in eV). My sense of scale is not off, these are just basic back of the envelope calculations. These machines simply do not exist. The 30 years was using an accelerator which is hundreds to thousands of times more powerful than anything that exists today (so in fact using real accelerators it would take more like thousands to millions of years). I think I've made my case quite clear:
1) Accelerator-driven systems are still nuclear power reactors and have all of the same issues with managing decay heat after shutdown, fuel fabrication, proliferation resistance (in fact, they're arguably much worse in this aspect), fission product volatility, etc. They might have been a neat idea 50 years ago when we didn't know much above passive reactivity control, but they're outdated today.
2) Direct beam fission product incineration isn't practical even in principle, simply because the machines needed to do it don't exist and I haven't even touched upon the practical difficulties (such as target cooling, volatility of products, equipment damage from the hard radiation spectrum produced, etc.)
3) The operation would be so monumentally expensive (the LHC cost 10 billion Euros and is nowhere near the beam intensity required) that it simply isn't going to happen.
I'm sorry that I have to put it to you this bluntly, because you seem like a sensible person, but you have no idea what you're talking about.

3 days ago
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New NRC Rule Supports Indefinite Storage of Nuclear Waste

brambus Re:What else can they do? (173 comments)

I was talking about how they all but shut down the nuclear industry 20-30 years ago, not what they're doing today.

3 days ago
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New NRC Rule Supports Indefinite Storage of Nuclear Waste

brambus Re:On site transmutation (173 comments)

Your proposal still risks meltdown while the accelerator controlled system may avoid that.

No, they don't avoid that. Meltdowns at both TMI and Fukushima occurred hours after the system had been completely shut down (Chernobyl wasn't a meltdown, they had a power excursion due to a prompt criticality situation in a faulty reactor design which was known to have this problem from the outset). This is caused due to decay heat from short-lived fission products which accumulated in the nuclear fuel as a result of fission. This is the same irrespective of whether fission was initiated by a neutron from a neutron criticality situation or a spallation neutron from an accelerator driver. So an even accelerator driven reactor still produces lots of decay heat, which must be dealt with.

For those, further fission through proton collision will do the trick. And yes, that costs energy. Notice we are not looking at neutron cross sections here.

You can't bust apart nuclei in meaningful quantities using a direct proton beam. There are no proton beams of sufficient intensity out there - even your article talked about that. And even assuming each particle causes a nucleus disintegration rather than just bouncing around due to coulombic repulsion, heating the material up instead of breaking a nucleus apart, the amounts of energy involved are monumental. To break apart 1kg of fission products with an average atomic mass of 100 using a 1A beam accelerator (Which doesn't even exist! Read your own reference!) would consume about 3GW of electricity, reject about 2GW of that as heat and would take about 2 weeks to do so, so breaking down 1t of fission products would take about 30 years!

Heck, we could accelerate the fission products themselves and have them as both bullet and target.

So you're proposing building a heavy ion collider of impossibly monumental proportions?! Such systems don't exist even conceptually, much less realistically. I mean this is thorium-powered car and solar-roadways type BS pontificating without any sense of scale. You need to really read up on your basic particle physics man, even basic back of the envelope calculations show that what you are proposing is ludicrous!

3 days ago
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New NRC Rule Supports Indefinite Storage of Nuclear Waste

brambus Re:On site transmutation (173 comments)

Gosh, mdsolar, you know just enough to confuse yourself into thinking you know it all. The page you cited talks about exactly what I talked about, an accelerator-driven power reactor that still produces fission product waste and notably doesn't destroy fission product nuclei by splitting them. You don't even have an idea of the energy required to do so. Below Fe56, fission is a net energy loss, even assuming you could somehow get the nucleus to fission (FP cross sections are tiny compared to TRUs). Essentially, you're proposing doing fusion power in reverse, which is crazy! Here's the money quote from your article (emphasis mine):

Essentially, current ATW proposals sacrifice effective transmutation for energy, and require several unproven technologies combined with concepts used in Generation IV breeder reactors like advanced processing and molten coolants. The idea of using accelerator neutrons to manipulate the reactor's neutron economy is a nice one, and indeed energy might plausibly be produced through burning the TRUs, but it is not a complete waste solution (especially in the case of long lived fission products) and requires significant engineering advances in accelerator, spallation, cooling, and reprocessing technology. Even if energy can be produced, there is little evidence that a combined system would be more effective than simply burning the TRUs in an ADS and then using the energy for a separate, dedicated ATW system. Even this scenario would require detailed processing of the wastes to high purities that hasn't been demonstrated.

The problem is, you don't understand what you're reading.

3 days ago
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New NRC Rule Supports Indefinite Storage of Nuclear Waste

brambus Re:What else can they do? (173 comments)

I admit I was oversimplifying a bit when I said the environmentalists caused nuclear R&D in this country to get all but killed outright. Of course it's a bit more complicated and you need to follow the money to find out who's really behind the push. Environmental organizations such as the Sierra Club and campaigns like Solar not nuclear have often been financed by fossil fuel industries, the reason being that these industries knew damn well that while solar & wind might pose a threat down the line but at present still require fossil fuel backup (thus cementing their position in the grid), nuclear posed an imminent threat should the US go and pull a French on them, kicking them off the grid in one or two decades. Nuclear development projects such as the IFR got caught in political cross fire and for some reason got labeled as being "Republican", so Democratic congresspeople like Kerry led a massive push against it in the early 90s to get it defunded, which they ultimately succeeded in doing in 1994. After the Republicans took office following the Clinton administration, their oil buddies sure as hell didn't want to see the project resurrected, so it was left alone. Ultimately, the IFR project was killed by a lack of political allies, the Democrats being backed by powerful environmental groups (who are often, but not always backed by Big Gas and friends, though they've also got strong grassroots movements) and the Republicans being a wholly-owned subsidiary of the fossil fuel industry.
Now if you look at counties who are less susceptible to industry lobbying with more centrally planned economies, like China and Russian, they are moving towards nuclear in a big way and are bringing it online both on-time and on-budget.

3 days ago
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New NRC Rule Supports Indefinite Storage of Nuclear Waste

brambus Re:On site transmutation (173 comments)

Reactors cause accidents. Accelerators won't.

I don't know which Amory Lovins lie tract you got this information from, but it is quite false, I assure you. Accelerator driven systems are *still* nuclear reactors, just subcritical ones, i.e. the reaction is non-self-sustaining. They still require heavy shielding and containment, they still require fuel fabrication, they still require high-power cooling systems while operating, they still require decay heat removal after shutdown and they still make fission product waste. The only meaningful difference is in how reactivity control is achieved while the reactor is going. If the operate in the fast neutron spectrum, they also have most or all of the drawbacks of fast reactors, such as require large fissile inventories to start up. In fact, if you want to use them to destroy fissile material without producing any new material (i.e. avoid breeding), you'd need to run them on pure weapons-grade fissile material, or accept huge amounts of neutron leakage, meaning you'll be supplying most of the fission neutrons via your accelerator = crazy high cost (the half a million bucks per kg I mentioned before).
Traditional reactors use control rods and the inherent physics of reactor core design to control the reaction rate. Accelerator driven systems use just the accelerators. Aside from a few crazy designs like the Russian RBMK that blew up at Chernobyl, all properly designed reactors are dynamically stable systems, so they can't have a runaway reaction simply due to the physics of how the core is designed (this is called a negative reactivity coefficient - temperature goes up, reactivity goes down, so the system self-stabilizes at a predesigned operational temperature). In cases of station blackout, shutdown systems initiate because of laws of physics, e.g. due to gas pressure or gravity, inserting control rods and stopping the reaction entirely. More modern designs like the IFR don't even need this, as the fuel pins themselves will go subcritical due to thermal expansion. These are just some of the failsafe approaches taken in traditional reactors to provide reactivity control. Of course, after shutdown, decay heat removal is still required, but it's also required in accelerator-driven systems!

It is expensive because of all the prior improper risk taking.

Look, I know you hate nuclear power with a passion, so it's in your interest to try and heap as many costs onto it as possible, but in reality, it's only because you have been sold a bag of lies. Don't take this the wrong way, but in my experience, hate is usually due to fear and fear due to ignorance. I'd humbly recommend you learn about how nuclear reactors actually work in more detail, so that you can understand that they aren't the ticking time bombs you presumably imagine them to be.

3 days ago
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New NRC Rule Supports Indefinite Storage of Nuclear Waste

brambus Re:central storage or n^x security guard costs / s (173 comments)

I'm quite aware of how radiotoxicity of spent nuclear fuel works. There are in fact graphs detailing it. Fast reactors and actinide burners prevent the actinides from entering the waste stream in the first place, hence why their waste is below original uranium ore radiotoxicity levels after a few hundred years. After that, you can essentially throw the stuff back into the pit you got it out of, knowing that you've actually lowered the overall radiotoxicity of the original material. For current LWRs on a once-through cycle this doesn't occur until some hundreds of thousands of years in the future.

4 days ago
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New NRC Rule Supports Indefinite Storage of Nuclear Waste

brambus Re:On site transmutation (173 comments)

Accelerators produce minuscule amounts of particles, so huge amounts of energy are be needed to produce enough spallation neutrons to fission the spent fuel. It takes about 50 MeV to produce a spallation neutron, assuming almost every neutron eventually produces a fission, it'll still produce >200 MeV per fission. What you're proposing is essentially a deeply subcritical power reactor that just dumps all the power produced over board. Just to give you a sense of scale involved here, to fission down 1 kg of plutonium-239 in spent fuel, you'd need to:
1) separate out the plutonium via some form of reprocessing (presumably PUREX) and fabricate a blanket of it
2) purchase a suitably large spallation target (that'll also get used up in the process)
3) put suitable neutron reflectors & shielding all around the system
4) almost half a million dollars worth of electricity to run the accelerator (assuming $0.07/kWh and the accelerator being ~95% efficient)
5) disposing of 22.34 GWh of waste heat, which at 35% conversion efficiency and $0.07/kWh would be worth just about $100000 more than the electrical cost needed to run the accelerator
6) this system still has all of the decay heat problems that conventional reactors have
What you're proposing is just a nuclear reactor with extremely shitty economics. Yes, you can do tricks like design the thing so that you only need to supply only the last fraction of criticality using the accelerator to cut down on the input power cost, but really the kicker here is that you're back in the power reactor business you wanted to get out of in the first place. Put simply, the only ones that'll want to burn down the actinide component of spent fuel are going to be utilities, and they'll do it for a profit using a system that's a heck of a lot cheaper to run than spending tens to hundreds of thousands of bucks per kg of material.
Now if you think "let's lose the accelerator and all its associated expense and complexity and just use the fuel itself as the neutron source", you will have arrived at the fast nuclear reactor, designed over half a century ago.

4 days ago
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New NRC Rule Supports Indefinite Storage of Nuclear Waste

brambus Re:central storage or n^x security guard costs / s (173 comments)

There is a workable solution - burn down the actinide contents so that after a few hundred years, it's below the activity levels of the original ore. No sensible nuclear engineer thinks sequestering it for hundreds of thousands of years is a good idea.

Thinking that we can find the equivalent of a smoke detector use (Americium) for high-level waste is very wishful thinking in my mind.

Not does it not require any wishful thinking, the physics and technology of it is pretty straightforward and well understood. 94% of typical once-through spent fuel is still uranium and a further 1% is higher actinides, all of which can be fissioned in the appropriate types of reactors to generate more energy and shorten its half life by at around 3 orders of magnitude. It's the policy decisions that are in the way.

4 days ago
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New NRC Rule Supports Indefinite Storage of Nuclear Waste

brambus Re:What else can they do? (173 comments)

Carter's ban was reversed a few years later. The true problem is the lack of a national policy on the way forward with this. The original nuclear pioneers envisioned us burning up the spent fuel in fast reactors. That was pretty much put on hold indefinitely when 20 years the Clinton administration cut the funding for the project just short of producing the first commercially viable fast reactor power plant designs. This could have been solved problem were it not for the environmentalist policy of stalling any progress on nuclear technology in order not to lose the political bargaining chips that R&D would have eradicated. The only thing they've achieved, though, is that it'll get developed somewhere else. In fact, using the future tense may not be necessary anymore.

4 days ago

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