Nuclear Energy - I need to vent/rant

Apollo20 said:
I worked as a research scientist in the Canadian nuclear industry for 23 years. Having studied CANDU reactors in great detail, I can say I would not want to live within 10 miles of one. Pickering Unit 3 (P3) had a serious LOCA in August 1983 from a pressure tube rupture that was not supposed to be possible (according to all the scientists at Chalk River).

Chalk River scientists also believed that the N2 annulus gas system used by all CANDUs at that time could not produce particulate carbon -14. When P3 was opened up for repairs in 1985, thousands of curies of particulate carbon-14 were released to the air and was soon found on swipes taken in the offices AND IN THE HOMES of staff working at Pickering.

And, let's face it, the long-term disposal of CANDU fuel IS a major problem. AECL has been working on this for 50 years and has not come up with a viable plan. So hundreds of thousands of hot fuel bundles are stored in glorified swimming pools that have been known to leak into the local ground water after just 25 years of operation.

And, by the way, a spent fuel storage bay makes a GREAT terrorist target!
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I'd like to know more about your background, as I've never ever heard a nuclear energy research scientist come out against the idea. Heard them say one variety of reactor or process was flawed, yes.

I've actually never liked the CANDU especially, but I've not seen any reason I wouldn't want to live near one. Are you aware of some of the things that come out of a coal stack?


The "spent fuel" issue has come up and been addressed before and what you are saying is the simplistic view which I have heard over and over and fails to address the actual physical nature of the stuff.

Furthermore, I'd be interested to know what scientist claimed it was impossible for a high pressure pipe to rupture. Given that there is no "infinately strong" metal and that pressure pipes of all sorts have had a tendency to rupture on occasion before.

This is of course, why there are contaimnet structures and why there are measures for this. One does not buy a fire extinguisher because theyexpect their house to catch fire, but because they know it can happen.

Is this the same scientist (the one with the pressure pipe which can not explode) who designed the "unsinkable ship" and the "Aircraft which simply cannot possibly crash ever"
 
Lonewulf said:
OH! You're so right! Subsidies... I never even thought of that! Nuclear has subsidies, so therefore all of the research, record keeping, and evidence MUST BE WRONG as to the price comparisons!

I mean, solar power would NEVER be subsidized!

http://www.theage.com.au/news/Natio...bsidy-for-homes/2007/05/08/1178390288210.html <--- obviously a link made by the evil nuclear scientists!

And wind energy... wind energy makes TONS of money, and thus needs NO subsidies at all!
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What I always find so frustrating is that these arguments about solar and wind potential are never with really people who deal with this stuff. It's established...

I mean, people in the industry.. You don't see them reasonably arguing that you can run a country on solar or wind. You hear environmentalists. You hear politicians.

Have you ever heard an engineer who works with distribution systems claim you can? have you ever heard the guys who sell wind trubines even claim it? No they use words like "help" and "Cut back out need."

But people who are actually part of the ins and outs... It's... just not an argument. It's established.


You can read this post I made on solar energy and what the "solar guy" who is in the solar energy industry says

He does say "everything said is about 95% true." I think he picks on me for giving estimates which are a bit too generous for solar energy effeciency.

I choose to go with the highest reasonable effeciency estimates I could find, because I would rather they be skewed slightly in the wrong direction. Like current solar cells are about 18% effecient in practice. I picked 20% as my estimate based on the "best cells under the best conditions" to be generous.

However it's basically agreed on
From a solar guy...

http://depletedcranium.com/?p=86
 
luddite said:
Sometimes I feel very naive, Buzzo, but this answer really surprised me. After all your talk about how safe nuclear was, about how we could just churn them out by the hundreds and put them anywhere, how the fuel was useless for weapons and so on

AND

how nuclear was necessary for improving the standard of living everywhere in the world,

I just thought you would support a civilian nuclear program everywhere. That you don't indicates that you recognize risks you don't want to talk about
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Well, well. The woo's out of the bag.
 
luddite said:
Wind potential that's been studied indicates that a fraction of the Earth's surface would do. The Dakotas and maybe Texas, for example, could do all of the United States.
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Don't you still find that a little excessive ?

A power plant the size of texas ?

Not at all. I wouldn't trust Iran either. But then you're in the position of trying to decide who gets power and who doesn't. You're in the position of watching regimes turn over and just hoping that dangerous materials don't fall into the hands of madmen or incompetents. These are the kinds of security concerns that have been brought up in the past and you've pooh-poohed. Can we rule out another Hitler?
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You're right!!! Let's stop moving forward because somebody might use something in some wrong way !

But you're wrong about it expanding class divides. It is rather a great social leveler. Income is one of the best indicators of carbon emissions. Make it expensive to emit and you hit the rich hardest.
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Not proportionally, no.
 
The reactor failure that was deemed to be "impossible" was a rapid fracturing of a zirconium alloy pressure tube. Chalk River scientists preached the "leak-before-break" scenario to the regulators for years back in the 1970s and early 80s. A "leak-before-break" didn't happen in the case of Pickering Unit 3 - instead a hydride blister unzipped and opened a gash about 1 meter long in a fraction of a second!
 
luddite said:
Not at all. I wouldn't trust Iran either. But then you're in the position of trying to decide who gets power and who doesn't. You're in the position of watching regimes turn over and just hoping that dangerous materials don't fall into the hands of madmen or incompetents. These are the kinds of security concerns that have been brought up in the past and you've pooh-poohed.
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No you don't go around deciding who gets power and who doesn't. You do get extremely concerned when you see an Islamic fundamentalist country which has called for "death to Israel" and has sponsored terrorist groups - (We're not talking "suspected" I mean Iran has literally done so it's a known fact.. They say they gave that up in the mid 1980's... yeah sure)

and they turn around and start a very large construction project on what they claim is a peacefully civillian nuclear energy system but which has no apparent use for power generation and is basically EXACTLY what you would expect a nuclear weapons program to look like.

This is what it looked like when Iran announced they had their first samples of enriched uranium:

ukeIran.jpg


I don't remember what words were used but they were not "We are pleased to have taken the first step in our process of diversifying our energy supply and assuring we are prepared for the eventual depletion of petroleum resources as well as moving toward less carbon intensive means of generating electricity"

Is anyone even still pretending this is really a peaceful electricity project going on?







Can we rule out another Hitler?
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I think so. The last of his fraternal line has already changed the name a long time ago and the only ones I know of still alive are getting older and have not yet reproduced.

Aside from maybe some neo-nazi I can't imagine anyone would want to keep that sir name anyway, just because of the stigma.

So I would say there probably won't be many more Hitler's. I don't know that there are even any living former hitlers. William Patrick Hitler died in the 1980's and his sons were born long after he changed his last name... so I wouldn't consider them to qualify wither way...
 
Apollo20 said:
The reactor failure that was deemed to be "impossible" was a rapid fracturing of a zirconium alloy pressure tube. Chalk River scientists preached the "leak-before-break" scenario to the regulators for years back in the 1970s and early 80s. A "leak-before-break" didn't happen in the case of Pickering Unit 3 - instead a hydride blister unzipped and opened a gash about 1 meter long in a fraction of a second!
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That doesn't sound like much of a problem. Large break LOCA analysis assumes a 4 foot section of the Coolant pipe mysteriously falls away.

A one meter gash seems small.

glenn
 
Glenn, how often does a 4 foot section of coolant pipe mysteriously fall away?
 
luddite said:
Glenn, how often does a 4 foot section of coolant pipe mysteriously fall away?
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It's never happened...but, the analysis has to be worst case. Typically, one assumes a big problem...the pipe thingy...off site power goes away, one diesel fails and the operators don't do anything for a half hour.

glenn
 
If the LOCA at Pickering was no big deal why did AECL spend $100 million dollars between 1983 and 2000 researching corrosion and hydriding of zirconium alloys and OPG, (the operator of Pickering NGS), spend several billion dollars retubing all of its Pickering reactors in the same time period?
 
luddite said:
Most environmentalists don't want a free market.
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I agree, except when they are talking about nuclear. Then many of them have to make the "if it can't survive in the market without subsides, then we shouldn't be using it" argument. Switch the subject to solar or wind, on the other hand, and they will complain that the government isn't giving enough money away for them.

As for the pipe, it is easier and more conservative to assume that the pipe simply disappears. A break in the pipe is harder to model and also is preferable to a complete dissapearance because what is left of the pipe will partially block the opening and slow the loss of colant.

That is a common approach to accident analysis in nuclear engineering -- design the plant to withstand a hypothetical (and physically impossible) accident that bounds (is worse than) an actual accident can be.
 
Apollo20 said:
If the LOCA at Pickering was no big deal why did AECL spend $100 million dollars between 1983 and 2000 researching corrosion and hydriding of zirconium alloys and OPG, (the operator of Pickering NGS), spend several billion dollars retubing all of its Pickering reactors in the same time period?
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Because regardless of the plant's ability to withstand such an accident while remaining safe, you have to understand the failure mechanism and replace defective equipment.

Nobody said that LOCAs aren't big deals. They are. But that doesn't mean the reactor is in an unsafe condition. If it were really unsafe, then all the plants would have been shut down until the replacement was complete. But that didn't happen.

Things like this have happened in the US as well. When you find an unexpected problem, you monitor it through more thurough and more frequent inspections at any plant where it may apply while you investigate the problem to see if it requires widespread replacements. One of the reasons the plants are designed with the defense in depth that they have is so that things like that can happen without the regulatory body having to decide that a bunch of reactors have to go down for preventative maintenance at the same time.
 
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Well I have done some research further on the incidents which were mentioned.

I've said before that I was never that fond of the candu reactors or using heavy water as the moderator anyway, but by "not fond of" I mean it's not the reactor design I like best... still way better than coal.

As has been mentioned before, the CANDU reactors do produce a decent amount of tritium, which can be seperated relatively easily from the coolant, (seperating hydrogen isotopes is the easiest of all, because titrium is 50% heavier than deuterium it's a lot easier than uranium isotopes where it's just <3%). But the tritium has caused some to be concerned in the past. I don't think it's much of a risk even if it all were released in a catastrophic leak.

But I was not aware of the fact that they produced carbon-14. Actually, they don't anymore, but at one time way back they used nitrogen as a secondary coolant for the moderator. Anyone who knows the first thing about reactions knows nitrogen has a massive neutron capture crosssection and creates not only c-14 but also hydrogen and high energy gamma rays on recoil.

But C-14 isn't that bad as far as isotopes go. It's a very low energy beta emitter and it is quickly diluted by the huge amounts of carbon in the environment. Obviously not all "curies" are created equal. I read the IAEA report on that reactor and it listed the incident, but it was not considered serious.

I didn't read anything about more than small amounts making their way into the enviornment. I'm not sure that they detected elevated levels in homes, but they may have. Clearly, you can test for this stuff at very low levels, since that's how they do carbon dating. So it may be it was ever so slightly elevated. But I don't know.


As for the rupture, I'm still a bit confused on that one as it sounds minor in all I read. Pressure tubes rupture. It happens. In coal plants, in nuke plants, in water treatment plants. It's no surprise that if you fill a tube with something under high pressure every once in a while one will fail. Obviously, this is accounted for and there's no huge safety threat from it as there are contaimnet measures.
 
It was a tube rupture? That explains why I couldn't find any info on it online other than the typical alarmist "Chernobyl in Quebec" articles. Here I thought we were talking about a serious problem. Tube ruptures, while a concern, are nowhere near as bad a LOCA elsewhere since they always carry low loss rates (these are small tubes) and because a tube can be sealed off easily. Heck, when we do thermal analyses for plants, we generally assume that 20% of the tubes in the steam generator have been plugged for one reason or another.
 
Apollo20 said:
And, by the way, a spent fuel storage bay makes a GREAT terrorist target!
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I'm curious about this, and I don't want to make it seem like this claim has gone uncontested.

Please explain how the terrorists will use the spent fuel, and why it would be any worse than if they used their target against plants that store deadly chemicals all over the place?
 
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