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Tag: nuclear

How to make a nuclear reactor disappear

Just a short blog post during a quiet period that has unfortunately reigned on this blog for a while. Recently during the voting for the German greentech awards something tremendously embarrassing happened! A nuclear reactor of all things had the audacity to win the voting. That led to a dilemma of course because nuclear anything can’t be allowed to win anything in Germany, especially not when the environment secretary himself is the patron of the award.

So what did they do, they changed the rules of course to ensure that the voting has no meaning (““selection of nominees and winners will ultimately be done independently by the Jury of Awards GreenTec. Legal action is excluded.”) and that nuclear will never be allowed to win (“and our jury reject nuclear energy in any form categorically!”). I wonder how they would treat geothermal energy (radioactive decay anyone?!?)…

The story is told much better over at the Rainer Klute’s blog, “How to stash a nuclear reactor away”, I suggest everyone read Rainers post and support his petition!

Now its time to return to the wonderful Swedish midsummer festivities exquisitely summarized in this IKEA commercial.

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Nuclear news

Together they are giving a picture that Russia is really beginning to go all in for nuclear. Of course Russia has always been a pioneer in the nuclear field, but despite that they “only” have 33 reactors running producing less than 18% of electricity.


Taken from the IAEA PRIS database


A few interesting videos of reactor experiments

During the 50’s and 60’s a number of experiments where conducted in the US to examine criticality accidents in light water reactors. One basically inserted large amounts of criticality (by ejecting control rods from the core) to see what happens. It is quite fascinating to watch the videos of the experiments. The first two videos are from the Borax experiments and the third one from SPERT, enjoy watching them!

I will try to find some time to write more about criticality, prompt criticality and feedbacks that keep reactors stable and how one calculates transients, but until then if someone technically minded wants to read more about the experiment I recommend searching on DOE’s information bride (



Radioactive tourism – A trip to the Ytterby mine

I am taking a online geology course for fun right now, the subject has always interested me and it is quite different from the maths heavy physics I am used to. Sweden has a grand history in geology, mineralogy and chemistry and chief among historic locations must be the mine in Ytterby, a suburb to Stockholm. In 1787 the lieutenant, chemist and amature geologist Carl Axel Arrhenius was sorting through the mine heap at Ytterby and discovered a unusually heavy black rock. Realizing that it must be a undiscovered mineral he sent samples of the rock to several chemists for analysis. The man that did the best job was Johan Gadolin and the mineral was named Gadolinite in his honor. The mineral contains, among other things, the element yttrium and it was the first of the rare earth elements to be discovered. Another 6 new elements where discovered in minerals from Ytterby and no less than 4 is named directly after the location (Yttrium, Terbium, Erbium and Ytterbium along with Skandium, Thulium and Holmium).

I happen to live in Stockholm which means a small field trip to Ytterby is a must and there I went a few weeks ago. Anyone that has been following the rare earth situation in China also knows that where there is rare earths usually one also finds Thorium, properly armed with a dosimeter I was looking forward to some rads!

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The first WHO and UNSCEAR reports on the health consequences of Fukushima

is on the way…. Nature has an article about it, here are some highlights.

The risk to the roughly 140,000 civilians who had been living within a few tens of kilometres of the plant seems even lower. Because detailed radiation measurements were un available at the time of the accident, the WHO estimated doses to the public, including radiation exposure from inhalation, ingestion and fallout. The agency concludes that most residents of Fukushima and neighbouring Japanese prefectures received a dose below 10 mSv. Residents of Namie town and Iitate village, two areas that were not evacuated until months after the accident, received 10–50 mSv. The government aims to keep public exposure from the accident below 20 mSv per year, but in the longer term it wants to decontaminate the region so that residents will receive no more than 1 mSv per year from the accident.

The WHO’s calculations are consistent with several health surveys conducted by Japanese scientists, which found civilian doses at or below the 1–15-mSv range, even among people living near the plant. One worrying exception is that infants in Namie town may have been exposed to enough iodine-131 to receive an estimated thyroid dose of 100–200 mSv, raising their risk of thyroid cancer. But data collected from 1,080 children in the region found that none had received a thyroid dose greater than 50 mSv. Chernobyl’s main cancer legacy in children was thyroid cancer.

But most importantly is this

A far greater health risk may come from the psychological stress created by the earthquake, tsunami and nuclear disaster. After Chernobyl, evacuees were more likely to experience post-traumatic stress disorder (PTSD) than the population as a whole, according to Evelyn Bromet, a psychiatric epidemiologist at the State University of New York, Stony Brook. The risk may be even greater at Fukushima. “I’ve never seen PTSD questionnaires like this,” she says of a survey being conducted by Fukushima Medical University. People are “utterly fearful and deeply angry. There’s nobody that they trust any more for information.”

To bad people like Sherman and Mangano, Gundersen, Busby, Caldicott, Matsumura and a host of other people and their fan clubs within the “environmental movement” are doing everything they can to spread excessive and scientifically unfounded fear of radiation.


Examining some old Fukushima news

An old news article is circulating around that states that 68 tons of fuel has melted in reactor number 1 and that it was close to breaching the bottom of the containment. The article is several months old but for some reason I have seen it pop up again on facebook so I though it is worth examining the article briefly. In particular I want to examine this statement.

Only 37 centimeters of concrete remains between the fuel and the vessel’s outermost steel wall in the most damaged area, TEPCO said.

This wording is repeatedly used by anti nuclear sources to imply that a much worse disaster was very close to happening. What the articles fail to mention however is that there is A LOT more concrete between the ground and the molten core. The reactor building itself is a very thick concrete structure. Will Davis, on his excellent blog Atomic Power Review, talked about this the first time the news about the number one vessel failure showed up last November. Some of what he wrote is worth repeating and I hope he doesn’t mind me repeating it here and also posting a picture from his blog.

The NHK report indicates a melt depth of about 2.1 feet(64 cm, my note /Johan). The distance to the ground is roughly eighteen times this depth from the dry well interior floor to grade. Below is a drawing from WASH-1082 which I’ve marked to show the distance from the dry well floor to the grade outside, which on the particular plant shown is 39′ 0″(11.8 meters, my note /Johan). I do not presently know the exact measurement at Fukushima Daiichi No. 1 but it is likely within ten percent of this measurement… meaning that in the worst case that TEPCO is describing, by its own data, the core material may have melted only about as much as 5% of the distance to the grade.

I encourage everyone to read the rest of his blog as it is by far the best information source for the Fukushima accident.


I also want to add this picture of the mark I containment that schematically shows the thick concrete even more clearly! Picture found at the blog “The capacity factor”.

So we see that there is a tremendous amount of concrete below the shell of the containment structure. The hints and suggestions that the core would only have to melt another 37 centimeters for a unnamed disaster to take place is obviously false. In reality the shell of the containment is integrated into a thick concrete structure and the molten core would have to melt through several more meters, likely around 10 meters, to get out of the reactor building itself.

The cleanup of the containment is going to be a very hard and messy job, much worse than the cleanup of TMI was. But the core is still a long long way from the ground.




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Challenge to nuclear opponents

It has always mystified me (and I think I can speak for all of us in NPYP) that someone can be anti-something when it comes to energy. Lets suppose for instance that someone declares himself to be anti-chemical energy, the logical follow up question to the fellow would of course be “what kind of chemical energy?”. The question is logical because there are so many different ways one can extract chemical energy, everything from burning cow dung in huts to the engine in your car to high tech gas turbines to dynamite. Our friend there probably didn’t even think of those distinctions when he made his statement, but what if he did? Let’s say he rebukes by stating he really means that he is anti coal. Even that statement can be challenged, it must by necessity be conditional otherwise it is moronic. If he is anti coal because of air pollution, then would he change his mind if there was a solution to the pollution? If someone developed a filter that reduced pollution levels to insignificant amount is fossil fuels then ok? Logically he should think so. If he is anti coal because of the immensely destructive coal mining, would he change his mind if environmentally sound mining practices where developed? The guy is presumably actually anti air pollution or anti dirty mines, not anti chemical energy or anti coal. He just never bothered to go through the chain of reasoning to understand what he really opposes in chemical energy.

Same can be said of any energy source, there is no rational reason to be against the energy source itself, rather one is against some undesirable effect due to the present application of the energy source. NPYP are not fans of coal by any means, but I dare say that if there was solid solutions to its problems, then none of us would oppose its use. There just isn’t any justifiable reason to oppose it if the problems are solved. There is no other way to rationally look at energy production.

The advantage with digging deep and specifying exactly what one is actually opposed to means opening up to the possibility of finding solutions! If someone simply state that they are anti windmills then the discussion pretty much ends right there. If the person instead states that the noise from windmills is disturbing then the discussion can turn to possible solutions to reduce noise. Everyone wins on that! There is no reason to be horribly emotional about the whole thing and cling to an anti-something idea so hard that one blocks any fruitful discussion and becomes blind to solutions.

A discussion goes no where until one gets to the core of the argument, which is, what properties of a specific energy source makes you oppose it and and how can it be improved so you no longer oppose it?

The frustrating thing in the nuclear debate is that the discussion never seems to reach that point. Ask leading environmentalists that exact question and they will squirm like a worm on a hook.

If someone specifies that they are opposed to nuclear energy due to the waste problem. Fine we say, but what exactly do you mean by the waste problem and what effect does the waste have that you find repulsive? If you are bothered by the possibility that the waste will hurt future generations, then lets discuss how to safely dispose of the waste. If you are anti nuclear because you are bothered by the safety of nuclear installations, then specify what level of safety is safe enough (obviously there must be a level where an activity is considered safe enough, otherwise the person in question would never get out of bed to shower for fear of slipping and dying) and lets discuss how to reach that.

But the discussion always ends before reaching that point because the “anti person” generally never  seems to be interested in solutions to the posed problems and they are usually not even able to state clearly why they consider the issue as a problem in the first place. This is not only valid for the nuclear debate, one sees the same tendencies in all kinds of discussion where there is a clear anti side. Anti genetic engineering, anti cars, anti meat, anti space exploration, you name it! It seems very hard for people to go past the simple emotional attachment of being against something and instead engage into a meaningful discussion about the issues. It is too easy to just be opposed to something, it is damned much harder to actually find solutions.

So to move the nuclear discussion into a more fruitful direction it would be enlightening if some nuclear opponents could specify what conditions nuclear would have to fulfill to be an acceptable energy source. Believe it or not even we have such conditions. I don’t think for instance anyone in NPYP wants to see more RBMK reactors built (the type of reactor at the Chernobyl plant) and just to speak for myself I have quite strict demands on what nuclear energy should be in the long run to be an acceptable energy source. I am not anti nuclear, but I am certainly anti towards some ways of extracting nuclear energy.

To summaries and to state the challenge again clearly.


What conditions would have to be fulfilled for you to consider nuclear an acceptable energy source?



Weekend reading

Activity is not very high here lately so I though I would provide you all with some nice weekend reading material.

First is the article “Energy as the ultimate raw material” by the nuclear energy pioneer Alvin Weinberg. Weinberg used to think of the big picture and this article showcases that. He outlines a few approaches to a asymptotic state of civilization, a state where humanity is using resources at a rate that is practically infinitely sustainable. In such a state humanity uses a lot of energy in order to produce the necessary raw materials from common rock, seawater etc.The article is from 1959 but well worth reading even today.

The second article is a blog post from Will Davis over at Atomic Power Review, “Vogtle COL approval vote indicates perspective on “nuclear renaissance”. I selected it because in it Will describes some the various reactors that where developed during the first decades of nuclear energy. In my opinion it speaks volumes of how restricted the view of nuclear energy has become, nuclear power today is pretty much identical to light water reactors, but that is just a fluke of history and some day tinkering with other designs will charge on at full speed again.

As the third article I give you Gismags “Feature: Small modular nuclear reactors – the future of energy?”. Aside from a few glaring technical errors or statements that doesn’t make a whole lot of sense, it gives a good overview of the developments going on with small modular reactors.

I also end the post with a small section from Freeman Dysons book “Disturbing the universe”. A fantastic book by a fantastic scientist! Any spelling errors are mine since I wrote out the paragraphs below.

The fundamental problem of the nuclear power industry is not reactor safety, not waste disposal, not the dangers of nuclear proliferation, real though all these problems are. The fundamental problem of the industry is that nobody any longer has any fun building reactors. It is inconceivable under present conditions that a group of enthusiast could assemble in a schoolhouse and design, build, test, license and sell a reactor within three years. Sometime between 1960 and 1970, the fun went out of the business.

The adventurers, the experimenters, the inventors, were driven out, and the accountants and managers took control. Not only in the private industry but also in the government laboratories, at Los Alamos, Livermore, Oak Ridge and Argonne, the groups of bright young people who used to build and invent and experiment with a great variety of reactors where disbanded. The accountants and managers decided that it was not cost effective to let bright people play with weird reactors. So the weird reactors disappeared and with them the chance of any radical improvement beyond our existing systems.

We are left with a very small number of reactor types in operation, each of them frozen into a huge bureaucratic organization that makes any substantial change impossible, each of them in various ways technically unsatisfactory, each of them less safe than many possible alternative designs which have been discarded. Nobody builds reactors for fun anymore. The spirit of the little red schoolhouse is dead. That, in my opinion, is what went wrong with nuclear power.

– Freeman Dyson



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