Archive for the 'environment' Category

about inspection optimization in nuclear energy

Friday, December 4th, 2009

In an earlier randform post about scaling factors in nuclear power generation I tried to explain what is implied if nuclear power generation is going to be increased. Among others I was talking about the risk of a nuclear accident which is going to rise by scaling things up. An important quantity in risk assessment in nuclear power generation is the core damage frequency. The corresponding Wikipedia article links to a ressource by the Electric Power Research Institute by which the probability of a damage of the nuclear core was in 2005 (i.e. the more dangerous type of fast breeder reactors, which will dominate in the future is included in this average only to a small amount) at 2*10^(-5)=0.00002 per reactor and year (there seem to be ressources which indicate that this frequency may be higher though).

This means that is if one has approx. 500 reactors worldwide the likelihood of a core damage somewhere in the world was in 2005 one damage in 100 years, if we take again a factor ten as in the randform post about scaling factors in nuclear power generation then this would rise to one core damage every 10 years. If we include an higher risk for fast breeders (which is a technology, which hasnt been tested exhaustively) then this likelihood rises again. Core damages are quite crucial because they can lead to a nuclear meltdown.

Other risks are therefore often calculated in relation to the core damage frequency. While answering to a comment about Leukemia I stumbled upon the “Studies on Applying Risk Informed In-Service Inspection for Indian Nuclear Power Plant and Heavy Water Plant” by G. Vinod from the reactor safety division at the indian Babha Atomic Research Centre in which probabilistic safety assessment techniques for indian nuclear power plants which among others are using the core damage frequency are discussed in particular with regard to optimizing inspection. A citation from the article

An optimum plan should be devised subjected to constraints such as risk to plant, cost of inspection and radiation exposure to workers, if the component is in radioactive area.

Its not clear to me to what extent inspection optimization may lead to an increase of the core damage frequency.

About the “Concept for an integrated energy-research program for Germany”

Friday, September 18th, 2009

There had been some uproar in mediascape-Germany about a study with the title “Konzept für ein integriertes Energieforschungsprogramm für Deutschland” (“Concept for an integrated energy-research program for Germany”). According to Financial times Deutschland” (FTD) the study was commissioned by the Federal Ministry of Education and Research however the study had been withheld from the public for 3 months.

The study is now -after the uproar- openly available. The reasons for the ministries policy of secrecy gave of course way to speculations in the press. So among others the study suggests that besides studying halite rock formations as a suitable geological formation for a final nuclear dump site, like the one in Gorleben it is meanwhile scientifically established that also Claystone formations may provide an alternative for a final nuclear waste repository. Since most of these rock formations can (according to FTD) be found in the current ministers “electoral homeland” Baden-Würtemberg and since the german elections will take place in about one and a half weeks it is understandable that the press identified this fact as a possible reason for the withheld (i.e. nobody wants a nuclear dump site in ones own backyard).

Another possible reason why the study was withheld was seen in the fact that the study suggests that an enforced research in nuclear power generation – and in particular in new nuclear fission technology could be a politically desired pathway in energy research (note the subtlety: the study does not suggest to pursue enforced research in nuclear energy, but states that enforced research in nuclear energy, in particular in new reactor types, may be a political request). This is in contrast to the current official political line of the minister and chancelor Angela Merkels party the CDU. Their official line (towards voters) is basically that power genration via nuclear fission should play NO role in Germanys future energy generation.

I have unfortunately currently not the time to study the study in full detail but nevertheless – here are some remarks to the study:

The study was made under the auspices of two german science/humanities academies, namely the National academy of science and the Berlin-Brandenburg Academy of Sciences and Humanities a third collaborator was the German Academy of Science and Engineering (Acatech), which claims itself to be a non profit agency, which represents the interests of German sciences and technology. Acatech has a strong connection to business, last but not least via funding. This has advantages and disadvantages.

Responsible for the text of the study are Prof. Dr. Frank Behrendt (Institut für Energietechnik, TU Berlin), Prof. Dr. Ortwin Renn (Abteilung für Technik – und Umweltsoziologie, Universität Stuttgart), Prof. Dr. Ferdi Schüth (Max- Planck-Institut für Kohlenforschung, Mülheim/Ruhr) and Prof. Dr. Eberhard Umbach (Forschungszentrum Karlsruhe), however the study encompasses contributions from numerous individuals (p.58 of the study) which are researchers from universities but also representatives of companies such as Siemens. As a remark: the company Siemens seems to intent to terminate its engagement within the french nuclear company AREVA, however according to this article it may replace its french engagement with a cooperation with the russian nuclear company Atomenergoprom. This should put the neutrality at least of parts of the study -namely those concerning nuclear power generation- under scrutiny.

A main argument of the study is that the challenges of Germany’s future power generation can only be dealt with in a – what the authors call- “systemic perspective” that is with an approach which integrates not only the scientific and technological demands of power generation but also the juridicial, sociological etc. aspects which are connected with it. The arguments are similar to the IPCC conclusions. For accomplishing this integration approach the study suggests among others to establish energy research clusters (similar to the US american Energy Frontier Research Center (EFRC), public-private partnerships like the british Energy Technologies Institute (ETI) and one central german energy research center which bundles the research activity and which serves as an outside representative for Germany’s energy research. The tasks and concrete realizations of such a center havent been yet not very much specified, however integrating and coordinating energy research is in my opinion definitely sound.

Moreover the study collects “no-regret” research options, like research in insulation improvements, energy efficiency, research in how necessary behavioural changes may be adressed appropriately, in how international agreements could be furthered etc. At this place I would have liked to see a stronger discussion of the problems related to patents/intellectual property rights obstructing technological development and international agreement processes.

Within the technological component the study identifies three main research sectors according to which politics can choose to put emphasis on. These are: regenerative energies, carbon based energies and finally -although as pointed out above there is currently no official political backing for this- nuclear energy. The technological aspects of each sector are introduced in the study in a socalled module.

I’d like to concentrate a bit on the nuclear energy module, since the text of the nuclear energy module is mildly put indeed controversial.

As already indicated the aspect that nuclear fission research may be pursued only with the goal of securing its safe pullback (which is the official political line!) is just a little side remark in the text.

In particular it is argued that in order to keep a fall back option on nuclear (fission) energy, Germany could feel strongly advised to support research in new fission technology and thus could feel the need to support the development of fast breeders and in particular in 4’th generation reactorsystems:

Deutschland kann sich aufgrund seiner Expertise hier an vorderster Stelle beteiligen, um unter anderem höchste Sicherheitsstandards zu etablieren.

(translation without guarantee: Germany may – based on its expertise – take part in this in the front row in order to establish among others highest security standards.)

The option that a fallback option on nuclear fission technology could also exist without a german research effort or accomplished with just a small german contribution like within an international noncommercially oriented community research project (my favoured option) is not mentioned.

The study mentions the necessity to keep a fallback option on nuclear fission due to the reason that climate change could have more dramatic consequences than expected, this was also annotated in an earlier randform post.

However the study suggests that such a fallback option may also be justified by the strong pressure which may be due to an international renaissance of nuclear fission technology and which may be due to raising energy needs (p.15) especially in regard to financial feasibility (p.12).

Yet the most problematic part of the nuclear module was the sentence:

“Außerdem müssen bei einer Wiederaufnahme der Forschungsarbeiten zu neuen Reaktoren bereits frühzeitig Ansätze entwickelt werden, mittels derer die Technologie gegebenenfalls umgesetzt werden könnte, ohne Widerständen zu begegnen oder – für den Fall, das dies nicht möglich ist – mit diesen Widerständen konstruktiv umzugehen.”

(translation without guarantee: Furthermore in case of a resumption of the research efforts concerning new reactor types one has to develop at an early stage approaches with which the technology could be realized without encountering resistance or – if this is not possible – develop approaches on how to deal with this resistances in a constructive way.)

I hope this sentence was a very unfortunate phrasing accident and that the authors do not really mean what they write here.

On the socalled Greiser-study

Sunday, September 6th, 2009

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According to Spiegel a new study by Eberhard Greiser on the correlation between living in the vicinity of a nuclear power plant and children Leukemia had been brought forward.

randform reported recently in a blog post about an earlier study (the socalled KIKK-study, see also: Kaatsch P, Spix C, Schulze-Rath R, Schmiedel S, Blettner M. Leukemia in young children living in the vicinity of German nuclear power plants. Int J Cancer 2008; 122 (4): 721-726) in which a correlation between living next to a german nuclear power plant and childhood leukemia was asserted. This very comprehensive study gave way to many discussions about nuclear power, however although the study established a correlation between children getting sick of Leukemia and living next to a nuclear power plant the KIKK-study could not identify a cause for that correlation. May be this was the reason why no political measures, like sending out warnings for those living close to a nuclear power plant were enforced. In particular it was argued that the measured radiation in the vicinity of a nuclear power plant could – due to its low value – not be accounted for an increased risk of developping Leukemia. However as pointed out earlier the KIKK-study doesn’t rule out this possibility either and there may be other risk factors, which could (and should) in principle be investigated.

The study by Eberhard Greiser (shortly called Greiser-study) is interesting. It is however of a different kind than the KIKK-study. First of all the KIKK study had been commissioned by the german Ministry of Environment and the Federal Office for Radiation Protection. The Greiser-Study had been commisioned by the german green party (which is against nuclear power generation). This shall put the neutrality of the Greiser-study under strong scrutiny. The KIKK study had been undertaken by the Institut for Medical Biometry, Epidemiology and Informatics at the University of Mainz and the German Childhood Cancer Registry (Kinderkrebsregister), the study by Greiser had been performed by him as a consultant at a consultant company called epi.consult, a company of which I couldn’t find a website. Nevertheless Eberhard Greiser seems to be a distinguished scholar (Biomedexperts link1,link2?), in particular he is mentioned as the founder of the Bremen Institute for Prevention Research and Social Medicine, given his publications on Biomedexperts and e.g. this book he seems to be an expert for epidemiological investigations. So in short – the academic reputation of this person could in principle reinforce some trust in the neutrality of the study.

Greisers study investigates given data in journal articles and cancer registries (in particular he includes the KIKK study). So Eberhard Greiser used more or less open accessible data (see also here in this randform post about cancer in Marine county) in order to perform a statistical analysis. He analyzed data of 80 nuclear power plants in the five countries: Germany, France, Great Britain, USA and Canada.

Main result of Greiser-study:
The Greiser-study displayed a statistically increased risk for children (up to age 24) to develop Leukemia due to living next to a nuclear power plant. The risk was increased by 13% to 24% with respect to the respective national average risk of developping Leukemia.

E. Greiser lists all his data sources, in particular he lists which source was used for investigating each of the 80 nuclear power plants. The data from each facility is then weighted in a socalled meta-analysis (a method which seems to be described in DerSimonean R., Laird N. Meta-analysis in clinical trials, 1986;7:177-188 and Greenland S. Quantitative Methods in the review of epidemiologic literature, Epidemiol Rev 1987; 9:1-30). This method was used in order to gain a statistically relevant evidence for the international comparision.

In order to understand the implications of the main result Eberhard Greiser mentions that passive smoking increases the risk of lung cancer by 13% to 19%.

Concluding it can be said that there is plenty of data about cancer occurrences available, especially on an international level. The Greiser-study displays this already at the example of only 5 countries. This data however should be analysed in a more neutral (and international) setting than in the Greiser-study in order to obtain a neutral matter-of-fact scientifically sound analysis of the health risks of nuclear energy. The above mentioned studies strongly indicate that such a health risk seems to exist. Moreover the risk seems to be high enough so that political measures may be necessary as they were e.g. undertaken in the case of passive smoking.

Lucifer’s toy lab

Wednesday, July 15th, 2009

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Last weakend we were doing a visit to the Deutsche Museum.

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broomm economy

Tuesday, April 7th, 2009

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on high teach speed

Sunday, January 25th, 2009

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A reader called Ingeborg was asking

>>>”Do you think that teaching did impair your research?”

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happy new year

Thursday, January 1st, 2009

randform wishes a happy new year to everybody!

just be careful – in particular given the rather bleak economic outlooks it will get even more easy to loose oneself in dreamworlds, so I wouldn’t wonder if the boom of the game industry is going to continue. In this TED video (via serious games) David Perry describes the evolution of video games, however of special interest in this video may be an -what he calls opinion of a student- which is a (realistic?) documentary about a self acclaimed video game addict (second part of the talk, the whole talk is about 20 min). The documentary describes the cognitive changes which are due to excessive video gaming.

nuclear vehicles

Thursday, November 20th, 2008

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This will be a post about cars, nuclear power and economic stimulus programs.

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about Gorleben

Wednesday, November 12th, 2008

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Someone was asking me wether I am pro or contra using Gorleben as a final nuclear waste repository.

The answer is: I don’t know.

Most of the containers brought there seem to be an interim solution, so at one point one is forced to think about what to do with the material. The salt dome at Gorleben which was originally planned as a final repository (in the late seventies) was declared (if I trust the Wikipedia link) by the Physikalisch-Technische Bundesanstalt (resource: Zusammenfassender Zwischenbericht über bisherige Ergebnisse der Standortuntersuchung in Gorleben. Mai 1983, Braunschweig as less suitable:

„Eine erste Bewertung des Deckgebirges hinsichtlich seiner Barrierenfunktion für potentielle kontaminierte Grundwässer zeigt, daß die über den zentralen Bereichen des Salzstocks Gorleben vorkommenden tonigen Sedimenten keine solche Mächtigkeit und durchgehende Verbreitung haben, daß sie in der Lage wären, Kontaminationen auf Dauer von der Biosphäre zurückzuhalten.

translation without guarantee: A first evaluation of the sediments above the dome with respect to their functioning as a barrier against potential contaminated ground water displays that the clay sediments above the central parts of the salt dome Gorleben do not have enough thickness and spreading in order to prevent in perpetuity the contamination of the biosphere.

And there are other reports which indicate that there may be more geological problems.
Moreover the decision for Gorleben as a final repository was influenced by political/non geological citeria, like the one that Gorleben used to be close to the border of the former GDR and thus economically less attractive.

So it seems that a profound investigation also of other possible locations and their comparision with Gorleben has to be made.

Last not least I feel quite uncomfortable with the notion of “final repository” in general. If it means that the stuff is dumped there and then more or less left alone (and thus in the long term forgotten) then this can become very problematic (see e.g. Asse II).

It is important that the problem of nuclear waste is always present in the public mind (so alone for that reason peaceful protest is usually good).

This implies that the information about nuclear waste repositories, former nuclear production sites and in general about (possibly) contaminated sites has to be easy accessible for everybody and in particular for future generations. In particular one would expect that there exists a detailed map about such sites in the internet (“a google earth for nuclear sites” ?), however I have found nothing of this kind even not on the page of the International Atomic Energy Agency like on the pages of their waste technology section. The Dirata Database (which was hard to find) is a first step. Moreover it is a challenge to adress the waste problem which is involved with small size waste like with these mini nuclear power plants (e.g. probably soon in Romania) and where one reads the following about a company called Hyperion (which seems to have already a six year waiting list):

“Because the Hyperion plants would be buried underground and guarded by a security detail, the company explains that they´ll be out of sight and safe from illegitimate uses.”

Next year, the company will submit an application to build the modules to the Nuclear Regulatory Commission.

As a matter of fact the world has to think about how to make important information of nowadays accessible to future generations. The Svalbard fault, where information about plants is kept is one example. The genetic information about nowadays people and animals may also be important information to store somewhere in a “world treasure box” (especially given all of the above). A map with information about nuclear sites certainly has to go as well into that treasure box.

->see also this BBC report about a lost US nuclear bomb over greenland (via Tagesschau.de). The cancer records in denmark seem to be sofar only partially online. It would be interesting to look into them like into these ones.

addition Jan. 28, 2020:
Here a link to a blog post on Ars Technica about the Nature Materials article , 2019. DOI: 10.1038/s41563-019-0579-x, “Self-accelerated corrosion of nuclear waste forms at material interfaces”, which illustrates that plans to store nuclear waste by putting it first into a layer of chemically inert, insoluble glass and then putting this into a stainless steel flask are basically not working when this type of containment is exposed to water.

addition Feb. 8, 2020:
The essay Death and succession among Finland’s nuclear waste experts is an essay by anthropologist Vincent Ialenti about how the death of a leading finnish engineer (with the pseudonym Seppo) concerned with nuclear waste management gives an exemplary insight into “a larger, global expert-loss drama.” The essay gives also a very brief descriptiosn about finnish methods of nuclear waste storage (see below).

I do not fully agree with Ialenti’s conclusions and interpretations, but it is an interesting read into a “drama”, that is not only taking place in nuclear engineering, but also in other technical fields. The “drama” is largely due to an understaffing of the technical sector in societies that are largely “run” (in an economical and political sense) by people with not so much technical expertise.
Ialenti describes:

Studying Seppo’s character and influence anthropologically is not about capturing exactly what he thought, precisely what he did, or how he did it. Rather, it’s about examining the effects of “what would Seppo do here?” moments, in which surviving colleagues brought recollections of the man to bear on their present work.

Ialenti suggests:

“I propose that nuclear experts pause for a moment to consider how they can best preserve the memory of an expert’s thinking patterns in their work lives. Cultivating that style of self-reflection can help nuclear experts better understand their predecessor’s insights that they may already be preserving.”

I think it is less “thinking patterns” per se that are sought with the question “what would Seppo do here?”, but more desicion making patterns, i.e. questions of where do you set priorities, where do you think more research is necessary etc. in order to make a decision. In important settings engineers usually already document why they decided to do something in this or that manner (sometimes this is though not openly possible) and there are by the way also computerized tools which support this, but of course the less time there is for performing technical tasks (like due to understaffing) the less time there is for documentation and instruction. Last but not least what seems to be asked for here (?) is to document an experts intuition. Good luck with that.

The essay contains some technical inlets and in particular one about finnish nuclear waste containers:

Massive metal casks will encapsulate Finland’s spent fuel rods for long-term storage. The outer canister (left) is a cylindrical sleeve of copper, one meter long and five centimeters thick, intended to protect a cast-iron insert (right, here with one fuel rod) from the corrosive effect of groundwater for at least 100 000 years. The cast iron itself resists the mechanical stresses of bedrock.

which refers to the addtion on Jan. 28, 2020.
Remark to this: The Standard electrode potential(table in german) of Copper and Iron are close together so there is not such a high voltage (potential difference) between the two metals, but according to the german table it is still 0.39V. That is Copper acts here as an Oxidizing agent and presumably if the container is not super tight then the iron might rust even faster than without copper container – or in other words the copper container is rather the “opposite” of an Galvanic anode. Copper is considerably easily dissolvable by acids (In that context one might think of sulfate in groundwater).

commemorating Tricastin

Sunday, November 9th, 2008

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On the occasion of the current protests over here in Germany against a castor transport of nuclear waste from La Hague to the rather unsecure nuclear waste storage unit at Gorleben* I’d like to commemorate the lately average at Tricasin.

*(see also reports about a nuclear waste storage facility in a salt mine called Asse II, which has to be closed due to leakage)