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PostPosted: Nov 15, 2008 1:45 am 
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I wouldn't cast aspersions on Americans who having been pioneers in fast breeders but are now unable to make their own fast burners under GNEP. These things happen to all. However fast breeders/burners and reprocessing are back on US agenda after shying off for decades. It is possible that in different political circumstances, Indians may have just gone faster on fast reactors and thorium rather than getting clearance for imports. Those lobbies are still strong in India and claim that clearance in Indian parliament for Indo-US agreement was obtained through bribing the members. Really free trade and exchange of ideas helps all concerned. All shades of opinion are expressed in India as in the US. I stand by my moderate stand that enough uranium (U238) and thorium (Th232) can be there for all the reactors if we breed the fissile material preferably in fast reactors. I also agree that sodium is an unduly hazardous coolant and should be replaced by inert gases or stable fused salts. Liquid or solid fuel shall remain debatable.


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PostPosted: Nov 15, 2008 7:15 am 
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Have you read nothing I've wrote or checked none of the links at all? There is no purpose to breeding at all! That the americans are pursuing fast breeders as some DOE money hole doesn't mean that uranium is running into some resource crunch. It means that someone was able to convince a politician that it might be a good idea. Theres a reason there hasn't ever been and wont ever be a fast breeder supported by the market: There's no market rationale for them.

The only breeder that makes any economic sense is the LFTR and thats because it can have lower capital and operational costs than LWRs. Without that, theres no point in breeders at all this side of a thousand years.

jagdish wrote:
It is possible that in different political circumstances, Indians may have just gone faster on fast reactors and thorium rather than getting clearance for imports.


If the Indians actually cared about resource security they would have pumped the money into subsidised uranium mines rather than any fast reactor program at all. The Americans are guilty of a similar issue with enrichment capacity by waiting for laser enrichment rather than simply upgrading from diffusion to centrifuge enrichment; But for some reason people just aren't capable of making sound decisions with objective data. Like simply keeping uranium mines open if you face import restrictions.


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PostPosted: Nov 15, 2008 7:43 am 
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dezakin wrote:
Theres a reason there hasn't ever been and wont ever be a fast breeder supported by the market: There's no market rationale for them.


The main property of a breeder is that they have a neutron excess. This will probably be used for transmutation in the first place, as a high cost in nuclear is the waste. More actinides means that a different, more costly, storage strategy is necessary. Any type of breeder isn't viable now, but become viable if one puts energy source independence high on the list.

dezakin wrote:
The only breeder that makes any economic sense is the LFTR and thats because it can have lower capital and operational costs than LWRs. Without that, theres no point in breeders at all this side of a thousand years.


You don't know that. Only MSR research reactors have been constructed. Furthermore there isn't 1 design which was approved, so you calculation of reduced capital cost isn't valid as more systems could be necessary. For the operational cost, I doubt that it is less, as all systems are more radioactive. This means more difficult maintenance and inspection operations. The fuel cost on the other hand is reduced...

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PostPosted: Nov 15, 2008 8:07 am 
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dezakin wrote:


The only breeder that makes any economic sense is the LFTR and thats because it can have lower capital and operational costs than LWRs. Without that, theres no point in breeders at all this side of a thousand years.



LFTR makes sense only because it breeds fissile material to burn thorium. (Designers of Indian PFBR considered the MSR but gave it up as an unproved technology) The opinion is by no means unanimous as its economy has not been proved. For a thermal reactor, even sufficient neutron economy to need fissile material is only once is a hope yet to be ascertained by actual functioning.


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PostPosted: Nov 15, 2008 8:14 am 
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STG wrote:
You don't know that. Only MSR research reactors have been constructed. Furthermore there isn't 1 design which was approved, so you calculation of reduced capital cost isn't valid as more systems could be necessary. For the operational cost, I doubt that it is less, as all systems are more radioactive. This means more difficult maintenance and inspection operations.

That's absolutely right: The range of MSR concepts alone, makes any cost estimates little more than dreaming in technicolor.
The tendency is to base these guesses on MSR research reactors.
To have any credibility, an apples-to-apples comparison is required -- for example with LWR or SFR research reactors of 50 years ago....


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PostPosted: Nov 15, 2008 9:47 am 
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jaro wrote:
STG wrote:
You don't know that. Only MSR research reactors have been constructed. Furthermore there isn't 1 design which was approved, so you calculation of reduced capital cost isn't valid as more systems could be necessary. For the operational cost, I doubt that it is less, as all systems are more radioactive. This means more difficult maintenance and inspection operations.

That's absolutely right: The range of MSR concepts alone, makes any cost estimates little more than dreaming in technicolor.
The tendency is to base these guesses on MSR research reactors.
To have any credibility, an apples-to-apples comparison is required -- for example with LWR or SFR research reactors of 50 years ago....

It is possible to make some preliminary inferences based on estimated materials and labor input into manufacture. All estimates would be speculative, but this is very much the case for the future cost of conventional generation III+ reactors as well. The future cost of renewable generation systems is also quite speculative, even in cases where current costs are known.


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PostPosted: Nov 15, 2008 11:18 am 
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The main motivation for LFTR is dealing with the waste. No matter the economics the public has a real concern over the waste. You can argue the the concern is way overblown but that arguement was lost decades ago. I contend that a new type of reactor can reopen this discussion with the public and with the actinides consumed we should be able to convince the public that the waste problem is solved. California has a law against building new nukes until the waste problem is solved. While LFTR isn't completely waste free it can reduce the problem dramatically so that by running LFTR's we can actually significantly reduce the EXISTING wastes.

While other concepts are around to deal with the wastes I believe LFTR does the job the best and appears to be economically viable. We will see how it turns out as the concepts are refined.


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PostPosted: Nov 15, 2008 12:26 pm 
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Lars wrote:
The main motivation for LFTR is dealing with the waste. No matter the economics the public has a real concern over the waste. You can argue the the concern is way overblown but that arguement was lost decades ago. I contend that a new type of reactor can reopen this discussion with the public and with the actinides consumed we should be able to convince the public that the waste problem is solved. California has a law against building new nukes until the waste problem is solved. While LFTR isn't completely waste free it can reduce the problem dramatically so that by running LFTR's we can actually significantly reduce the EXISTING wastes.

While other concepts are around to deal with the wastes I believe LFTR does the job the best and appears to be economically viable. We will see how it turns out as the concepts are refined.


I can see your line of reasoning for the general public and the politicians, it makes sense. As a LWR operator I can tell you what I like most about the LFTR concept is that it operates at atmospheric pressure, the reactor can theoretically load follow as welll as any fossil or hydro plant and the liquid homogeneous fuel design concept seems inherently more safe than the solid heterogeneous fuel designs we use now. Other probably big selling points are a brayton cycle turbine with it's ~50% cycle efficiency is possible even likely. That factor alone is going to really help the bottom line to utilities.

My point is there are selling points to the general public that are very compelling but there are also selling points to nuclear industry professionals that are just as compelling.


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PostPosted: Nov 15, 2008 5:56 pm 
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STG wrote:
dezakin wrote:
Theres a reason there hasn't ever been and wont ever be a fast breeder supported by the market: There's no market rationale for them.


The main property of a breeder is that they have a neutron excess. This will probably be used for transmutation in the first place, as a high cost in nuclear is the waste. More actinides means that a different, more costly, storage strategy is necessary. Any type of breeder isn't viable now, but become viable if one puts energy source independence high on the list.

Nuclear waste doesn't have any cost except imaginary costs for waste disposal. Dry cask storage is as expensive as a parking lot. However reprocessing spent fuel weather in a breeder regime or simply for MOX fuel is not inexpensive. If energy source independence is valued, the most cost effective way to achieve it is to open more mines.

STG wrote:
dezakin wrote:
The only breeder that makes any economic sense is the LFTR and thats because it can have lower capital and operational costs than LWRs. Without that, theres no point in breeders at all this side of a thousand years.


You don't know that. Only MSR research reactors have been constructed. Furthermore there isn't 1 design which was approved, so you calculation of reduced capital cost isn't valid as more systems could be necessary. For the operational cost, I doubt that it is less, as all systems are more radioactive. This means more difficult maintenance and inspection operations. The fuel cost on the other hand is reduced...

You're right, I dont know that MSRs will be competitive, meaning I dont know if any future reactor will be competitive with LWRs. But anything that has higher capital cost wont ever be competitive, and I dont forsee any solid fuel breeder being lower in capital cost than a once through reactor.

The only reason MSRs can possibly do it is that they dont have to do all the fuel fabrication and processing steps that make breeders inherently more expensive operationally than once through regimes. If they cant keep operational and capital costs lower than once through reactors, theres no compelling economic reason to have any breeders at all.


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PostPosted: Nov 15, 2008 6:31 pm 
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dezakin wrote:
If energy source independence is valued, the most cost effective way to achieve it is to open more mines.

So all those Japanese and Indian scientists researching economic ways of recovering uranium from the sea water, are totally off-track ?
How do they manage to get ANY funding at all, considering that "to open more mines" is so much more straight forward ?
They must be engaging in a space-program-style "because its there" challenge....
Seems puzzling, to say the least !

dezakin wrote:
I dont forsee any solid fuel breeder being lower in capital cost than a once through reactor.

Who said LMFRs can't operate in once-through mode ?
They get three to four times higher burnup than LWRs, without the high-pressure vessel of either LWRs or PBMRs (which use similar LEU level fuel).


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PostPosted: Nov 15, 2008 8:23 pm 
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dezakin wrote:
Nuclear waste doesn't have any cost except imaginary costs for waste disposal. Dry cask storage is as expensive as a parking lot. However reprocessing spent fuel weather in a breeder regime or simply for MOX fuel is not inexpensive. If energy source independence is valued, the most cost effective way to achieve it is to open more mines.


That's ridiculous! There will be no permanent dry cask (or wet cask) storage ever. That's simply not a waste storage strategy, it's just for now as the amount of nuclear waste isn't considerable enough to open permanent storage facilities.

I like you idea to open more mines. But when taking into account the independence of my country (Belgium), there are unfortunately no mines...

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PostPosted: Nov 15, 2008 8:52 pm 
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jaro wrote:
dezakin wrote:
If energy source independence is valued, the most cost effective way to achieve it is to open more mines.

So all those Japanese and Indian scientists researching economic ways of recovering uranium from the sea water, are totally off-track ?
How do they manage to get ANY funding at all, considering that "to open more mines" is so much more straight forward ?
They must be engaging in a space-program-style "because its there" challenge....


Dezakin's argument is perhaps true in theory, however in practice opening new mines opens a Pandora box full of environmental activists and lawyers, adding both material and social-prestige costs.

Also, once the uranium price from sea extraction is established, it caps any future uranium price, which is useful for the (infinite (that is about ~10^8 years from now)) sustainability argument.


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PostPosted: Nov 16, 2008 8:34 am 
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jaro wrote:
dezakin wrote:
If energy source independence is valued, the most cost effective way to achieve it is to open more mines.

So all those Japanese and Indian scientists researching economic ways of recovering uranium from the sea water, are totally off-track ?
How do they manage to get ANY funding at all, considering that "to open more mines" is so much more straight forward ?

The same way nuclear fusion, wind, solar, and fast breeder reactors get funding. People get funding for all kinds of ideas with no future.

jaro wrote:
dezakin wrote:
I dont forsee any solid fuel breeder being lower in capital cost than a once through reactor.

Who said LMFRs can't operate in once-through mode ?
They get three to four times higher burnup than LWRs, without the high-pressure vessel of either LWRs or PBMRs (which use similar LEU level fuel).

True, and if they can get capital costs competitive with LWRs then they can compete in once through cycles. I dont find that likely after the past four decades if trying.


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PostPosted: Nov 16, 2008 8:40 am 
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STG wrote:
dezakin wrote:
Nuclear waste doesn't have any cost except imaginary costs for waste disposal. Dry cask storage is as expensive as a parking lot. However reprocessing spent fuel weather in a breeder regime or simply for MOX fuel is not inexpensive. If energy source independence is valued, the most cost effective way to achieve it is to open more mines.


That's ridiculous! There will be no permanent dry cask (or wet cask) storage ever. That's simply not a waste storage strategy, it's just for now as the amount of nuclear waste isn't considerable enough to open permanent storage facilities.

I'm sorry, but you aren't making a coherent argument against indefinate dry cask storage. It works well enough for several centuries, which honestly is all we have to worry about. In several centuries we can use a better solution, or just reseal them at near zero cost because of discounting.

Quote:
I like you idea to open more mines. But when taking into account the independence of my country (Belgium), there are unfortunately no mines...

If Belgium really wanted energy independance they could mine old coal ash for uranium at a price below MOX fuel. But honestly the notion of Belgium being independant any way but legally is quite ludicrous.


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PostPosted: Nov 16, 2008 8:44 am 
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STG wrote:
dezakin wrote:
Nuclear waste doesn't have any cost except imaginary costs for waste disposal. Dry cask storage is as expensive as a parking lot. However reprocessing spent fuel weather in a breeder regime or simply for MOX fuel is not inexpensive. If energy source independence is valued, the most cost effective way to achieve it is to open more mines.


That's ridiculous! There will be no permanent dry cask (or wet cask) storage ever. That's simply not a waste storage strategy, it's just for now as the amount of nuclear waste isn't considerable enough to open permanent storage facilities.

That's correct.
The intention is to leave the door open for eventual reprocessing & recycling of the large amount of unfissioned U stored in the SNF.

As regards "Dry cask storage is as expensive as a parking lot," that is of course incorrect:
Besides the development and licensing costs, the actual equipment cost is on the order of several million dollars per unit -- depending on unit size (the larger units cost more, but are cheaper on a per-ton-SNF basis; unit costs must also include a share of site prep costs, heavy gantry crane and/or cask hauler, shielded loading flask, etc.).
Operating costs include monitoring of containment, and of course security.
A helluva "parking lot," if you ask me....


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