The Nuclear Power Thread

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New to the thread and basically feel our energy production should be 100% nuclear, fission for now, fusion in the future if we get it going.

Re spent fuel and waste (apologies if this has been discussed), I thought part of the problem is that the nuclear industry started largely to produce weapons grade materials, which is why IFR reactors heavily regulated (non prolif etc), however IFR can burn in principle all the fuel, this would allow us to consume our current wast stock and produce nearly zero waste. Sure there will be small amounts of bad stuff that will need to be stored, or potentially neutralized in newer reactors. Thorium would get around that proliferation issue, but thorium fuel reactors not well developed because no possibility of nuclear weapon grade materials, thorium fueled IFR molten salt would be great.

Another interesting idea never properly followed because pure fusion is more of a priority is the fission/fusion hybrid. Basically non net energy producing fusion reactor as a fast neutron source that triggers fission in other wise nonfissile fuels, eg spent fuel or thorium. Inherently safe because there is no need for critical mass. Molten salt loop with neutron source cavity, extract heat as it exits the neutron chamber and then goes back around.

The costs would be much more manageable if building more smaller reactors vs single large highly specialized buildings.

I'm a huge fan of SMR.
 

Astronuc

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. . . the nuclear industry started largely to produce weapons grade materials
No, the nuclear industry, i.e., commercial nuclear power industry, was never intended to produce weapons grade material. There were special production reactors, outside of the commercial power generating plants, that were used for that purpose. Fast reactor technology, including IFR, was restricted and some information remains restricted.
 
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Well maybe not in the US, but as far as I know in the USSR they did plan to use commercial reactors (some of them at least) for plutonium production one of the reasons why the RBMK was chosen as it had the option to refuel while being online, I think I've read that other countries had similar ideas,I'm sure others will be able to explain this better.
 
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Both in the US and then USSR the civilian programs sprang up from military development, so while they may not be intended to produce weapons grade materials, they can, which is the issue. I would say this is largely because they inherited the basic technology developed early on that was intended to make weapons grade stuff, EBR-1 was the first reactor to make electricity and it was a research breeder.

There doesn't seem to be much motivation to build thorium reactors and there is clear evidence historically that this is mainly due to the lack of weapons applications.

Eg from wiki:
"Weinberg realized that you could use thorium in an entirely new kind of reactor, one that would have zero risk of meltdown. . . . his team built a working reactor . . . . and he spent the rest of his 18-year tenure trying to make thorium the heart of the nation’s atomic power effort. He failed. Uranium reactors had already been established, and Hyman Rickover, de facto head of the US nuclear program, wanted the plutonium from uranium-powered nuclear plants to make bombs. Increasingly shunted aside, Weinberg was finally forced out in 1973.[10] "
 
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while they may not be intended to produce weapons grade materials, they can, which is the issue. I would say this is largely because they inherited the basic technology developed early on...
Well, that statement would require some work to back it up, especially if you stick with that present time. As far as I know many of the Gen. I. reactors indeed had dual purpose: some of the Gen.II. were still able to produce Pu on acceptable scale (but I don't know about actual example when it happened): but further on Pu more and more became hindrance instead. Gen.III. already cannot be used to produce Pu - unless you totally ruin the economy of the operation.

One has to admit that Gen.I. reactors were kept operational for surprisinly long time, but right now the only example still running should be somewhere in North Korea (I mean, commercial reactor. At least, in name.)
Some RBMKs are still running from Gen. II.. That's indeed an issue but not really because of any possibility of Pu production.
 
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Well, that statement would require some work to back it up, especially if you stick with that present time. As far as I know many of the Gen. I. reactors indeed had dual purpose: some of the Gen.II. were still able to produce Pu on acceptable scale (but I don't know about actual example when it happened): but further on Pu more and more became hindrance instead. Gen.III. already cannot be used to produce Pu - unless you totally ruin the economy of the operation.

One has to admit that Gen.I. reactors were kept operational for surprisinly long time, but right now the only example still running should be somewhere in North Korea (I mean, commercial reactor. At least, in name.)
Some RBMKs are still running from Gen. II.. That's indeed an issue but not really because of any possibility of Pu production.

Keep in mind was generalizing a little to avoid writing a novel as well as talking historically, ie there is no denying the nuclear industry sprang from the military programs in the early 50's, that doesn't mean today all plants exist to make bomb materials. Then a nuclear program includes all the things needed for such a program, eg fuel processing, enrichment, reactors etc. So if you can enrich uranium, its not a large leap to enrich that uranium further to make weapons, both U235 and Pu239 are suitable for the big booms.
 

Astronuc

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Both in the US and then USSR the civilian programs sprang up from military development, so while they may not be intended to produce weapons grade materials, they can, which is the issue. I would say this is largely because they inherited the basic technology developed early on that was intended to make weapons grade stuff, EBR-1 was the first reactor to make electricity and it was a research breeder.
While there is a loose connection between civilian nuclear power programs and those developed for the military, commercial nuclear plants were never designed to produce weapons material, certainly not LWRs. The US had 9 production reactors at the Hanford site - starting with B-reactor (1943-1968) and ending with N-reactor (1963-1987). N-reactor was the only plant built for dual-purpose, including electrical generation.

LWRs more or less grew out of the Naval propulsion program, and there was no plan to make weapons material. The four major manufacturers were Westinghouse, General Electric, Combustion Engineering and Babcock and Wilcox, and there were minor players like Allis-Chalmers (which had purchased ACF Industries Nuclear Energy Products Division).

The USSR also has dedicated production reactors, not including the RBMK type, which were not civilian.

On the other hand, British Magnox reactors were designed with the dual purpose of producing electrical power and plutonium-239 for the nascent nuclear weapons program in Britain.

There doesn't seem to be much motivation to build thorium reactors and there is clear evidence historically that this is mainly due to the lack of weapons applications.
Not so.

"Weinberg realized that you could use thorium in an entirely new kind of reactor, one that would have zero risk of meltdown. . . . his team built a working reactor . . . . and he spent the rest of his 18-year tenure trying to make thorium the heart of the nation’s atomic power effort. He failed. Uranium reactors had already been established, and Hyman Rickover, de facto head of the US nuclear program, wanted the plutonium from uranium-powered nuclear plants to make bombs. Increasingly shunted aside, Weinberg was finally forced out in 1973.[10] "
The statement is from an article by journalist Richard Martin in Wired magazine and reflects his opinion, not the reality at the time. AEC wanted to pursue liquid metal fast reactor technology, while discontinuing the molten salt program, which was originally tied to Aircraft Nuclear Propulsion. There were still numerous technical challenges in MSR technology at the time. The whole Wikipedia article is problematic.

Rickover was head of the Naval Nuclear Propulsion program, not "the defacto head of US nuclear program."

A light water breeder reactor concept (using thorium) was tested at Shippingport, August 1977 - September 1982 for about 29,000 effective full power hours.
Argonne National Laboratory, ANL-87-2, FINAL REPORT FOR THE LIGHT WATER BREEDER REACTOR
PROOF-OF-BREEDING ANALYTICAL SUPPORT PROJECT, May 1987

WAPD-1600, Water Coold Breeder Program Summary Report, October 1987

Another program was conducted at Indian Point 1. The fuel was processed at West Valley Nuclear Fuel Services (Nov 1968 - Jan 1969) and shipped to ORNL as U-nitrate solution. ORNL converted the nitrate to oxide form. (ORNL/TM-13600)

People are taking a look at Molten Salt Concepts again, including both chloride and fluoride based systems.
 
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Maybe the fact that rbmk reactors only require 2% refined uranium and could possibly manufacture plutonium on the cheap?
A guess ....but super unlikely since there are much more efficient ways to manufacture weapons grade fuel.
Being able to run a reactor on 2% enriched fuel is probably cheaper.
 

Astronuc

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Unfortunately, Pilgrim Nuclear Power Station Shut Down Permanently, as of May 31, 2019

PLYMOUTH, Mass. – Control room operators at Entergy’s Pilgrim Nuclear Power Station, located in Plymouth, Massachusetts, shut down its reactor for the final time on Friday, May 31, at 5:28 p.m. The decision to shut down Pilgrim was the result of a number of financial factors, including low wholesale energy prices.
Entergy’s remaining operating nuclear power plants in merchant power markets - Indian Point Unit 2 and Unit 3, in New York, and Palisades Power Plant, in Michigan, are scheduled to be shut down in 2020, 2021, and 2022, respectively. These closures, along with the sale of these plants to decommissioning specialty companies, mark the end of Entergy’s participation in merchant power markets and its return to a pure-play utility.


 

Astronuc

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The problem with non-scientific media reporting on science, engineering or technology in which the author is not an expert:

To control the rate of fission in a nuclear power plant, reactors use control rods. Constructed from elements such as silver and iridium, the control rods absorb neutrons released during fission and slow down the rate of fission.
from

Many western PWRs use silver-indium-cadmium (Ag-In-Cd, or AIC for short). The above quote mentions silver and iridium. We do not use iridium, but indium. Be careful in reading non-scientific literature/media articles.
 

etudiant

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Truly sad, a huge and reliable power source, regulated to economic death.
What I cannot understand is how the various catastrophic climate change believers can simultaneously fight tooth and nail to block the safest non greenhouse gas emitting power technology.
 
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I'm glad there is at least some players developing new gen reactors, companies like terrestrial energy and nuscale give me hope!
 

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