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Report: Nuclear Plants Should Focus On Risks Posed By External Events

brambus Re:already done (116 comments)

If something is a magnitude higher (factor 10x - 30x, as you pointed out), it is not 'comparable' in its effect to the 'original' thing. It is quite a difference whether I drink *one* beer or 10 - 30.

Except that here we're talking about far smaller effects, more in line with 1 drop vs 10-30 drops of beer. Stick to facts and not analogies.

You try to compare stuff that can't be compared. A cosmic ray, a high energy ion, is crossing my body. Along its path it destroys a DNA strand here and there and kills some cells completely. Incorporating a radioactive element into your body is a bit different.

In what significant capacity? Radioactive element decay produces exactly the same kind of particles (high-energy electrons & gammas; high-energy ions being notably absent in fission product decay and mind you, high-energy ions are much more dangerous, so cosmic rays might even win from a danger perspective particle-by-particle).

Yes the 'Sievert modeling guys' try to 'compensate' the different effects to get a 'uniform' threat indicator. Makes no sense IMHO, as all those slightly different forms of radiation have completely different effects.

Your humble opinion on the matter is your right to have, but dismissing the work of researchers and professionals in the field without evidence would at best net you a label of science denier. Unless you can produce good research to substantiate your opinion, it'll remain just that - opinion.

Plutonium e.g. settles in the bone marrow ... the deadly dose for a human is something like 50 nano grams, perhaps 100, don't remember.

This is the problem when you listen to non-scientists like Ralph Nader and even a cursory read of the Wikipedia article on Plutonium's toxicity would have given you tons of references to studies, research and experiments done which essentially debunks this. Plutonium is toxic for sure, but it's nowhere near the levels you assume it is.

Iodine accumulates mainly in the thyroid, causing cancer there. It seems you can prevent that with high doses of Iodine intake, and Thyroid cancer seems relatively easy to treat and surviving rates are high.

I-131 is the primary problem child in inadvertent radiation releases, since there's plenty of it (~3% fission yield), it's highly mobile, it's intensely radioactive and easily bioaccumulates as you describe. After a few weeks, though, it decays away completely into stable Xe-131. There is also I-129, however its radiotoxicity is billions of times lower than I-131, so it's not really much of a problem once diluted.

Cesium accumulates in bones and sinew ... I assume in muscles as well.

Correct. Add Sr-90 to that.

So, your 10x - 30x increase of radiation versus 'normal' background level still simply measures what you can count with a geiger counter. It does not take into account what happens if you inhale some dust on a dry summer day ... perhaps working in a field with your shirt of covert with sweat when the dust accumulates on your skin.

Not correct. Sieverts are units of committed dose and all of the factors you mention have been considered in its calculation. Geiger counters just measure counts - disintegrations per second. To get a Sievert measurement what we do is we measure counts, then we take samples and employ systems such as mass spectrometry and gamma ray spectrometry to measure the exact radionuclides present and their proportions. These are then combined with a radionuclide-specific weighting factor to arrive at the final Sievert rating for biological risks. Of course not all radiation measurements performed are this involved and frequently Sievert ratings are derived from using simpler methods from pre-computed tables and known local radionuclide abundances. Essentially though what you're doing is saying that health physicists don't understand their own profession.

It does not take into account what you get if you eat something that 'accumulates' the radioactive material, like a chicken or its eggs, or a fish, that have 100x higher level of radioactive Cesium than the measurement you make. So suddenly we jump from your '10x - 30x' to the more realistic '10000x - 30000x' because a human living there eats an egg or an apple or a fish that was harvested/caught there.

Care to cite sources? Most of the articles I've seen citing such numbers (such as this one) are reporting deltas relative to natural abundance of a given radionuclide, which for any short-lived synthetic radionuclide is necessarily going to be extremely low (since it doesn't occur naturally and decays rapidly, at least on a geological time-scale). So what if the original abundance was 100 atoms per gram of body mass (and yes, we can measure such minute quantities), who cares if it's elevated by 100x or even 30000x. 10000 atoms or even 3000000 atoms per gram of body weight of Cs-137 is still so low that it's utterly inconsequential. By comparison, your body contains on average ~48085714285714285 atoms per gram of body mass of radioactive K-40, equivalent to 1155906593 Cs-137 atoms per gram when adjusted to a 30 year half-life. Both K-40 and Cs-137 accumulate in the same organs, since Cesium chemically mimics Potassium and both decay with similar modes with K-40 being a modest winner in terms of danger ([K-40 decay modes], [Cs-137 decay modes]).

Do you really think the exclusive zones exist because some idiots who have no clue overreact?

Of course not and I never said so.

In THE country that has the MOST experience with radiation victims?

And also the country that has had sizable amounts of fissile material and fission products spread over two fairly large cities, notably zero of which became a radioactive wasteland (in fact, here's a pic from my last visit to Hiroshima a few years ago - lovely city, my favorite in all of Japan). That is not to say that the radiation from these events didn't cause problems, it did.

You do know that according to normal regulations the whole coast north east of Fukushima beyond Tokyo, roughly 10 - 20 million people ought to be evacuated?

Sources?

4 hours ago
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Stanford Team Creates Stable Lithium Anode Using Honeycomb Film

brambus Re:More Range Needed (112 comments)

What about the majority of people who live in dense cities in apartment buildings without private driveways and/or parking spaces that are simply not practical to electrify. You know, it's easy to solve the problem for relatively rich folks, but most people in the world live more like this or this (myself included). We park our cars out on the streets, drive around mostly in or near the city and fill up perhaps once a month. Are we supposed to go charge our cars once or twice a week for a few hours at some remote location?

13 hours ago
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

brambus Re:already done (116 comments)

Comparing the 'natural' intake of C14 and other elements 'in a normal' amount with the levels in Fukushima makes you a moron. Not C14 or other minimal intake.

Contrary to your quite uneducated assertion that background radiation in a "normal" amount is somehow inconsequential compared with the radiation levels at Fukushima, they are rather comparable. We have quantified these things quite accurately. Terrestrial background is anywhere from 0.1 uSv/h (Japan) to 0.3 uSv/h (USA) in most places on the planet, ignoring outliers. By comparison, the Fukushima exclusion zone typically ranges from 0.1 uSv/h to ~15 uSv/h with the median being somewhere close to 3 uSv/h or about 10-30x background. This is comparable to radiation exposure on a long-haul flight, as I've shown you, and that has so far not been shown to result in any increased risk, even in people who work for the airline industry and spend a sizable amount of their lives in this environment.

Cosmic Ray != radioactive iod or caesium

From a radiotoxicity standpoint, they are in fact not really distinct. You may recall that Sievert is a unit of committed dose, so it expresses biological effects, not just raw counts, and is capable of accounting for the differences between internal and external emitters. Now you could argue that whole-body exposure numbers are too simplistic to accurately asses ionizing radiation impact, and I'd agree (for certain radionuclides), but this has been considered and more accurate models are available, they're just not used very often in discussions, because they're too complex to easily wrap your mind around. For a first-degree approximation, though, whole-body exposure numbers seem to be quite a good rule of thumb.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

brambus Re:already done (116 comments)

Gah, the stupid, it burns!

Natural radioactivity is mainly something that hits you from the 'outside'... it hits your skin

Except for the ~5kBq of K-40 in your nerves. And the C-14 in all of your tissues. Also, cosmic radiation doesn't stop on your skin - it's comprised of extremely high energy particles at 1 GeV or more. Those sort of energies make the radiation from nuclear reactors seem like child's play. That is not to say that you'd rather be inside of a nuclear reactor - most definitely not, the flux there is many orders of magnitude larger - but it does show that cosmic rays don't just "hit your skin", but instead fire right through you and irradiate your internals quite easily.

First of all a healthy person has no Uranium or Thorium in his body.

I'd be careful with throwing around superlatives like "none", but it's probably fair to say that the abundance of actinides in most humans would be classed as "trace" at best.

you are again mixing up external radiation by natural sources with radioactive elements incorporated into the body

Except that both K-40 and C-14 are both natural and inside your body. In fact, we use C-14 abundance in tissues to date when organisms died. Whether something is or isn't natural has no bearing on where it is harmful.

The fallout is measurable every where in north Japan.

This statement, while true, is misleading, or at the very least oversimplified. We have extremely sensitive measurement equipment, but the mere detection of the presence of a radionuclide does not in itself imply any danger from it. What needs to be assessed is the particular type of radionuclide, its abundance and sample distribution, in order to be able to at least roughly assess the potential biological impacts. In pretty much any scoop e.g. topsoil you'd be able to find all manner of toxic stuff, from mercury through arsenic, lead and even to uranium - this is simply a consequence of the magnitude of Avogadro's number.

I'll leave you with just one tiny factiod: long-haul flights are associated with elevated exposure to cosmic rays, easily 20-30x sea-level background and comparable to some of the hotter parts of the Fukushima exclusion zone. This has been repeatedly assessed and demonstrated. As such, one would expect to find radiation-related cancer clusters among airline crew, who spend a sizable amount of their lives in this elevated radiation environment. And yet, no reliable evidence for this has been found so far.

yesterday
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Report: Nuclear Plants Should Focus On Risks Posed By External Events

brambus Re:How would that be even helpful? (116 comments)

Japan is a bunch of islands for crying out loud.

While true, it is quite an oversimplification. Japan is very mountainous even near the shores, in some places, and it would not have been impossible to place the plant a little further "uphill" to prevent this from happening. There are several reason they placed it right on the shore, one of them being construction purposes. LWRs consist of some very heavy single-piece components and it's much easier to ship them in via boat than it is to transport them over the road. In addition, you have a readily available source of large amounts of cooling water in the world's largest heatsink.

However, had TEPCO not been a bunch of colossal asshats and not skimped on the construction and piping costs, they could have just as easily placed the thing a few miles inland and at higher elevation and none of this would have happened. In fact, if Japan ever decides to build liquid-metal cooled fast breeder reactors, it is absolutely imperative they place it somewhere it can't ever get flooded. If OTOH they decide to go with molten-salt reactors (and they should!), they could place them pretty much where ever they want, because fluoride salts don't react with water, aren't water-soluble, don't operate under high pressure and their large liquid range allows for high temperature of operation, which in turn means that passive air cooling in the event of a plant blackout is far easier to do.

2 days ago
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Greenpeace: Amazon Fire Burns More Coal and Gas Than It Should

brambus Re:Greenpeace... (281 comments)

what? I thought dam technology was already here. Are you telling me I get to invent pumping water into a reservoirs to store potential energy and the release it when the is a higher demand?

Dam hydroelectric power is already pretty much maxed out globally, since there's only limited numbers of suitable sites and flows.

Pumped hydro, meanwhile, cannot scale to the required energy volumes and is excessively expensive (despite being the cheapest storage option yet). It really falls apart when you consider the problem quantitatively (using Germany as an example here):

  • Germany averages ~60GW of power use over the course of a day.
  • They have 36 pumped storage plants with a total capacity of ~37.7GWh, which means they could power their existing grid for ~30 minutes before running out of water.
  • Variability in wind & solar resources means that in order to approach a 100% renewable grid you'll need at least 1-2 week's worth of storage, but at 60GW average per day, this means ~20000TWh total storage capacity. So far, they've got ~1/500th of that, so they'd need to build ~18000 new pumped hydro plants. This is quite simply not going to happen (there aren't that many sites or that much money in their economy to do that).
  • Aha! But wind & solar will cover each other and with smart grids & stuff we can lower the energy storage demand dramatically! Right? Well, no. To reliably back up 4GW even taking wind & solar complements into account would require ~440 pumped hydro plants, which when extrapolated out to 60GW still boosts this number back ~7000 and a rough cost of 1.44 trillion Euros (about 1/2 of Germany's yearly 2.73 trillion Euro GDP, or ~5x the German federal budget of $250 billion Euros) - and keep in mind this is without any transmission upgrades and without putting a single kW of generation capacity on the grid, just the storage to solve the intermittency problem.

Put simply, this cannot and will not be built.

2 days ago
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Greenpeace: Amazon Fire Burns More Coal and Gas Than It Should

brambus Apple 100% renewable? (281 comments)

Really? Solar is being mentioned a lot in the report with respect to Apple. So I presume, their datacenters have "cut the cord" and run completely off of their rooftop solar installations? Or is it simply installing solar panels offsite and doing net metering, "100% renewable" being hit when their grid feed-in is equivalent to their consumption? If so, then this is pure greenwashing, since they're still using the external electrical grid, which is most notably nowhere near 100% renewable, because it needs to be reliable. It's classic externalizing of the storage cost to somebody else and ignoring it, while feeling good about oneself.

2 days ago
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Greenpeace: Amazon Fire Burns More Coal and Gas Than It Should

brambus Re:Greenpeace... (281 comments)

"Dirty" is a very loose term without a rigorous definition, so you can make it be pretty much anything you like. For example, both wind and solar PV have a pretty serious environmental impact just from a raw materials mining perspective, only you don't see it, because most of it happens in places populated by people of a different skin color. Regardless, compared to fossil fuels (mostly coal), it's impact is pretty reserved, so I'm willing to give it a pass. Nuclear is similar, unless something goes really wrong, and even then the impacted areas are mostly deserted of people, not nature (which quite happily trades that niche in exchange for being pushed out of their natural habitats by people).

As for lethality, that is actually an understood and quantifiable factor and indeed nuclear comes out on top and that's even assuming the worst-case deaths from Chernobyl (4000 excess deaths over the next 25 years, 50 confirmed so far) and the linear-no-threshold model of radiation exposure risks. How can renewables be worse? Quite simply because wind and solar are extremely diffuse power sources, so they require lots of manpower to install. This typically takes place at elevated places and a non-trivial amount of people fall to their deaths.

2 days ago
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Greenpeace: Amazon Fire Burns More Coal and Gas Than It Should

brambus Re:Greenpeace... (281 comments)

For example, when there's an excess of power being produced, utilise some of it to do stuff like cracking water into hydrogen, etc. for use in cars; then when the wind drops just cut production of hydrogen rather than having to deal with a shortfall on the grid at large.

Good luck with that. Wind has been shown to vary by at least 30x on a day-to-day basis even at national scale(*) (and much more on an hour-by-hour or minute-by-minute scale) and solar obviously varies by infinity (zero output at night). There's two solutions: either massive energy storage on a scale not seen before, or never let intermittent power sources climb over some small percentage of supply (~25%-30% seems to be the threshold). The former requires fundamental breakthroughs which have yet to materialize and may never arrive. The latter requires deployment of nuclear to offset the CO2 emissions from the remaining 3/4 of the power mix and has already been done (France's grid is ~3/4 nuclear). Greenpeace - a religious cult at this point - prefers the former. Pragmatic environmentalists - such as George Monbiot and James Hansen - prefer the latter.

(*) In case you don't speak german, this graph shows german wind power production at daily resolution for 2011. Nameplate installed capacity: 29GW. Maximum output with 99% availability: 0.9GW.

2 days ago
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One Trillion Bq Released By Nuclear Debris Removal At Fukushima So Far

brambus Re:My daugher had 33 MBq injected last week (190 comments)

Before I sign off from this thread: Do you know of a good, authoritative account of the Fukushima event?

I don't, sorry. I find that there's tons of misinformation and downright falsehood about the event out there, both by tepco and anti-nuke activists, and I'm not gonna waste my time plowing through it and fact-checking every single line. I'm a technologist and as such much rather concern myself with the technology of newer safer and cleaner nuclear power than with politics.

2 days ago
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Western US States Using Up Ground Water At an Alarming Rate

brambus Re:Once again, resource shortages come down to ene (369 comments)

Surface reservoirs are being depleted as well, but regardless, taking for Oregon, 946km^2, how much would so much building space cost? Remember, this 946km^2 is just the collection area, not the whole thing, but let's have a look at the cost of materials. You'll need a transparent roof for which the article you linked suggests glass. Cost: $10/ft^2, or about $100/m^2. Multiply 946km^2 and you get $94 billion just for the glass, or about 1.5x the size of the entire Oregon state budget. This is just not workable.

3 days ago
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Western US States Using Up Ground Water At an Alarming Rate

brambus Re:Once again, resource shortages come down to ene (369 comments)

Can you provide some figures as to the land use and cost of such a system? The best I could find were pretty depressive numbers. The average US household of three uses ~1000L/d and there are ~115.2 million households. Using solar PV and reverse osmosis one sq meter of solar panel can produce around 200L/d, so ~5sqm per household and 576 sq km of total panel area - just on this alone it's a total non-starter before we even get to the costs of the RO plants, transmission lines, storage systems, etc.

3 days ago
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One Trillion Bq Released By Nuclear Debris Removal At Fukushima So Far

brambus Re:My daugher had 33 MBq injected last week (190 comments)

Thanks.

By "a mess" I meant the fact that what was supposed to be inside the fuel rods came to the outside. That's plenty of a mess for me ;-)

Agreed, but that's because of the incident, siting and management of the plant, not the cleanup. I'd hang those tepco management fuckers by the balls for mismanaging the plant so badly.

It is already in the form of HTO.

Right, that's what I forgot. You're correct that Tritium originates from reactor operations, not radioactive decay after the accident had occurred, but in LWRs it appears to be a by-product of fission reactions (1 in 10000). The neutron absorption pathway is mainly present in HWRs. There is one more Tritium generation path, but it doesn't happen in LWRs (Lithium-6 neutron capture). According to some TEPCO report, Tritium in the cooling water at Fukushima is currently being produced at a rate of ~0.64g per year - how exactly that happens, I'm not sure, since there's no neutron source present at this point. The only explanation I can come up with is that a small portion of the corium is in such a configuration that some low level of neutron moderation is going on, given that moderator (water) is present, but this is pure speculation. Overall the whole of the Fukushima accident shows what a lousy coolant and moderator water is. It works fine for a submarine, I guess, but it's ludicrous to use for gigawatt-scale reactors.

Oh, I wrote Sr-99 above where I meant -90 and Cs-133 where I should have written -137.

I understood what you meant, don't worry.

3 days ago
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One Trillion Bq Released By Nuclear Debris Removal At Fukushima So Far

brambus Re:My daugher had 33 MBq injected last week (190 comments)

Still, they have managed to make a mess with plenty of actinides, strontium-99 and caesium-133 all over the place which was emphatically *not* meant to happen.

Well, no argument about whether the power plant was improperly sited (it clearly was) or improperly managed (it clearly was), but I'd hold off on the amount of radiation released as being "a mess" that the Japanese cleanup operation had much to do with. I ran a quick set of calculations on the numbers in this article and assuming all of the release was cesium (which it unfortunately didn't say), I estimated they released only about 340mg of Cs-137 in this cleanup operation (about 0.64ml by volume). I challenge you to find a cleanup operation that can track all pieces down to the last gram of material. That it is not to say that they shouldn't try to do better - clearly they should - but I'm not prepared to lay blame on them for not getting an extremely hard job done to ideal conditions. If the bulk of the material was Tritium, as you say, then it's even less volume/mass than this.

And as for Tritium, at a density of ~0.27kg/m^3 (kinda comparable to helium's 0.18kg/m^3 and much below air's 1.275kg/m^3), I'd say it's not a big deal since it'll just float up in the atmosphere and probably escape to space, *unless* it burns and forms T2O molecules which would sink down towards the ground and possibly get bioabsorbed. Hydrogen has an auto-ignition temperature of ~500C, so I wouldn't really worry about that happening, but maybe I'm making a mistake somewhere. If you have more data, can you comment on my analysis?

3 days ago
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One Trillion Bq Released By Nuclear Debris Removal At Fukushima So Far

brambus Re:My daugher had 33 MBq injected last week (190 comments)

33MBq of what? If it's Tc99m, then it's gone from her system in ~3 days while emitting a total of ~1 trillion 140 keV gamma photons. Now consider the following horror: your body contains ~5kBq of radioactive Potassium-40, where each decay produces betas (90%) and gammas (10%) of 10x the energy for your entire lifetime! Oh noes! So how much is that in about 80 years? About 10 trillion events, but at 10x the energy, so about 100x more energy dumped, not to speak of that beta radiation has a much shorter mean free path than gammas, so the impact is about 500-1000x worse than that of the "useless" medical procedure. And now consider that this isn't the only source of background radiation affecting your body (just the majority source of internal emitters).

Honestly, calm down and enjoy life. Big numbers without context don't mean anything.

3 days ago
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Lawrence Krauss: Congress Is Trying To Defund Scientists At Energy Department

brambus Re:Que surprise? (289 comments)

Our politicians are a bunch of pork-minded, short-sighted luddite political hacks more concerned with their privileges than with doing what's best for the American public?

John Oliver nailed it.

4 days ago
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Western US States Using Up Ground Water At an Alarming Rate

brambus Once again, resource shortages come down to energy (369 comments)

There's plenty of water on this planet, more than we could ever hope for, the only trouble is, it needs expensive desalinization, which ultimately comes down to having the energy available to perform the process. We have the technologies to do it more cheaply, but we're choosing not to use them - high temperature nuclear reactors can desalinate water by using waste heat from the reactor and end this water problem once and for all. I wonder if our future descendants will look at us with as much pity as we do at the first cave men who were struggling with mastering fire.

4 days ago
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UK Users Overwhelmingly Spurn Broadband Filters

brambus Re:More inconvienient than the average filter. (115 comments)

Way to equivocate google images being used for classwork by kids with school-sponsored use for non-educational purposes (assembly). Also, many of the cases you cite would constitute fair use, but due to the corrupt system we have they're not challenged, you just tuck your tail in and run.

Hell, some of the largest companies are getting sued for using a photograph from the Internet without permission in their advertising etc. - this is a symptom of people NOT being taught about copyright law when they are in school

Indeed, for example you apparently weren't educated on the difference between "educational non-profit" and "commercial for-profit" use; the latter clearly not being fair use and being something I argued for.

I'm stopping your kid's school getting sued for 10 x damages for wilfull infringement of copyright and having to pay thousands that would be better spent on, say, computers or properly licensed software or books or teachers

Could you please, I don't know, save that money on the shitty commercial software to police their thoughts over the net and instead get to educating them about the value of open-source, sharing and open collaboration? Just a thought.

5 days ago

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