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Old 03-21-2011, 03:25 PM   #21
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Originally Posted by Joe Perez View Post
Solar would be great if it were always daytime (and if we had the capacity to cover an area four times larger than the surface of all of the land masses on earth with solar panels).
The moon. Problem solved. There are designs to put a huge bank of solar arrays on the moon and microwave the power back to Earth. It could power something like half the world due to the amount of light and radiation that can be captured from the moon's surface. Only problem is building it and maintaining it. Crap hits the moon all the time, so we'd basically need people rotating back and forth to fix panels. Then again, it could probably have a missile defense type system to burn anything smaller than a minivan before it hit.

http://gizmodo.com/#!5552774/lets-co...n-solar-panels
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Old 03-21-2011, 03:38 PM   #22
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Originally Posted by JasonC SBB View Post
Here's another great chart
http://xkcd.com/radiation/
"lowest one year dose clearly linked to increased cancer risk (2000 mSv, 2Sv)"
so what's the amount to UNclearly cause cancer?
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Old 03-21-2011, 03:56 PM   #23
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Go walk around chernobyl's site for a few days without protection.
You may not be aware of this, but they actually have tour groups nowadays. There are several companies that offer this service. A few examples:

http://www.tourkiev.com/chernobyltour/
http://www.ukrainianweb.com/chernobyl_ukraine.htm

You spend a whole day at the site, exploring the abandoned town of Pripyat, checking out the reactor facility (closest distance is 200m for tour groups- academic types and filmmakers can actually go inside), etc.

I'm pretty sure that the tour guides spend more than "a few days" on site, and even though they're not wearing bunny suits, I haven't heard of them dropping dead en masse from radiation poisoning.




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that's the problem with nuclear disasters. it's a lasting damage. if a gas plant or coal plant fails destructively, **** just burns down and is gone. You wont get sick or die investigating it a couple days later.
I made this point earlier, but there's another reason why Chernobyl is not comparable to Fuku, or TMI, or any other nuke plant disaster which has ever happened or could ever happen.

At Chernobyl, the core itself exploded. It didn't melt down, it didn't crack and release puffs of steam, it didn't catch on fire. It physically exploded and was ejected thousands of feet into the air, owing to the horrendous design of the thing (positive void coefficient, graphite moderator, graphite-tipped control rods, no pressure vessel, no containment, etc) with the result the pulverized uranium fuel rained down over a huge area.

And that's the difference.

The actual uranium fuel itself was blown to pieces and scattered over an area of hundreds of square miles, where it settled on the ground.

At Fuku, worst-case, we have fuel catching on fire in the pools and emitting airborne radioactive isotopes. Not uranium, which tends to hang around and cause havoc for a long time, but ***** elements like Cesium and Iodine that just float away. Same thing that happened at Three Mile Island when they vented containment into the atmosphere. Radiation readings spiked, then fell back to normal once it was all over. Nothing radioactive lingered in the area, and there is no exclusion zone.

And regardless of how bad it gets in the fuel pools at Fuku, that is precisely what will happen here. Yeah, the plant itself is a writeoff. They may be able to tear it down and clean it all up as they have done TMI-2, or they might just have to entomb it. But it's not as though some huge chunk of central Japan is going to be closed off for the next thousand years, or even the next six months. They'll have to dispose of some of this season's agricultural output, and some cows are probably going to get slaughtered, but that's about it. Mark my words: by this time next year, life around Fuku will be back to normal (well, normal for an area that got nailed with a 9.0 earthquake followed by a Hollywood-style tsunami.)



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Originally Posted by chicksdigmiatas View Post
People fail to mention that coal plants also produce radioactive elements.
Yeah, the amount of radioactive fly ash that's emitted by all of the coal-burning plants in the US in one year vastly exceeds the amount of radiation that's been emitted by all of the nuclear plants in the world (including Chernobyl) ever. But that's not even the whole story.



As Braineack alluded to, the real killer is particulate emissions. The exact numbers vary wildly, but one of the more reasonable-sounding reports I've read suggests that, worldwide, there are approximately 900,000 deaths annually as a result of inhalation of fine particulate matter (air pollution); asthma, heart attacks, emphysema, lung cancer, etc. Roughly 25% of this pollution is attributable to fossil-fuel-based power generation, making for about 225,000 stiffs a year.

And that ignores all of the secondary effects. People killed while mining / drilling, coastlines drenched in oil, pipelines exploding and leveling whole neighborhoods, etc.


Now, tally up all of the deaths related to nuclear power. All of them, ever.

It's actually kind of difficult, since 1/3 of the population is going to get cancer anyway, but taking the rather pessimistic estimate from the above report, projecting outwards for another 70 years from today (to account for the cumulative effects of all the people exposed at Chernobyl), the worst-case plausible counts tally up to just over 33,000. That's not 33,000 a year, that's 33,000 total in the whole history of nuclear power.

In other words, the production of energy from fossil fuels kills about seven times the number of people in a single year than have been killed as a consequence of all nuclear power generation over the past 50 years, and nearly as many as were killed (again, cumulatively) by the atomic bombings of Hiroshima and Nagasaki in 1945.


Yeah.
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Old 03-22-2011, 11:14 AM   #24
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The public needs to be educated towards this subject. However, that will hurt some oil king pin's pocket therefore is easier to say "ban this ****, is radioactive."

I recently did a presentation on nuclear power in a class. I took a little poll around work and on the street regarding the subject, nothing crazy just a few "yes or no," and common knowledge questions. It was ridiculous the amount of people that really do not know anything about nuclear power, yet denominate nuclear power as "dangerous." Some went even as far as to say is equal or less efficient that other sources such as SOLAR!!! (talk about media propaganda )

Soon after the events in Japan I had one of the person that I polled walk up to me and say: see why nuclear power is dangerous. I fought the desire of slapping her across the face for being a ----. The public needs to be well informed about the subject. However, nuclear power is indeed the inconvenient true solution to our power demand need.
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Old 03-22-2011, 12:09 PM   #25
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No nukes. But also no oil drilling (kills ducks), no oil importation (funds terrorists / depletes economy), no coal (kills lots of coal miners), no hydro (dams kill fish and alter the local ecology), etc.

So basically we need to generate less electricity, but at the same time, we all need to buy electric / plugin hybrid cars. How did you say we were going to charge them?
Here's a book by a founding member of Greenpeace:
Confessions of a Greenpeace Dropout: The Making of a Sensible Environmentalist
http://www.amazon.com/Confessions-Gr.../dp/0986480827

His own words:
http://www.vancouversun.com/technolo...767/story.html
Quote:
You could call me a Greenpeace dropout, but that is not an entirely accurate description of how or why I left the organization 15 years after I helped create it. I'd like to think Greenpeace left me, rather than the other way around, but that too is not entirely correct.

The truth is Greenpeace and I had divergent evolutions. I became a sensible environmentalist; Greenpeace became increasingly senseless as it adopted an agenda that is anti-science, anti-business, and downright anti-human. This is the story of our transformations.
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Old 03-22-2011, 01:05 PM   #26
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Originally Posted by Patrick Moore
Greenpeace became increasingly senseless as it adopted an agenda that is anti-science, anti-business, and downright anti-human.
Quote:
The global warming movement is not about global warming. It is about the creation of an international political control arrangement by which bureaucrats who favor socialism can gain control over the international economy.

This strategy was stated boldly by economist Robert Heilbroner in 1990.
http://en.wikipedia.org/wiki/Robert_Heilbroner
Heilbroner, the multi-millionaire socialist and author of the best-selling history of economic thought, The Worldly Philosophers, wrote the manifesto for these bureaucrats. He did this in an article, "Reflections: After Communism," published by The New Yorker (Sept. 10, 1990).
http://www.newyorker.com/archive/199...ARDS_000357236

Quote:
The free market economy will always outproduce a socialist economy. Get used to it, he said.

Then, in the second section, he called on his socialist peers to get behind the ecology movement. Here, he said, is the best political means for promoting central planning, despite its inefficiency. In the name of ecology, he said, socialists can get a hearing from politicians and voters.

Here's what Heilbroner wrote:

The direction in which things are headed is some version of capitalism, whatever its title. In Eastern Europe, the new system is referred to as Not Socialism. Socialism may not continue as an important force now that Communism is finished. But another way of looking at socialism is as the society that must emerge if humanity is to cope with the ecological burden that economic growth is placing on the environment. From this perspective, the long vista after Communism leads through capitalism into a still unexplored world that must be safely attained and settled before it can be named.
Heilbroner did not care that a worldwide government-run economic planning system would not be called called socialism. He just wanted to see the system set up.

Heilbroner's peers got the message. That was what Kyoto was all about.
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Old 03-22-2011, 01:46 PM   #27
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At Chernobyl, the core itself exploded.

At Fuku, worst-case, we have fuel catching on fire in the pools and emitting airborne radioactive isotopes. Not uranium, which tends to hang around and cause havoc for a long time, but ***** elements like Cesium and Iodine that just float away.
+1
Chernobyl was much like a dirty bomb in effect.

Fuku is completely different. It is releasing infinitesimally smaller amounts of radiation in elements with ridiculously short half lives.

Get a Barium enema and your **** glows in the dark. We subject patients to more radiation on purpose every day in this country than being 3 miles downwind of Fukushima produced at it's peak. And again what Fuku released has already broken down and harmlessly dissipated within minutes of release. I'll have to find the article on the subject I read last night. This is all about the hype for the 24hr news cycle.
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Old 03-22-2011, 03:38 PM   #28
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No, seriously Joe. Why?
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Old 03-22-2011, 05:28 PM   #29
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I would love to see a net comparison of nuclear and coal:

- deaths and shortened lives PER TERAWATT-HOUR GENERATED due to radiation, air pollution, and mining, including 3 Mile Island and Fukushima

(don't include the Russian designs, it's like looking at a Yugo and saying Hondas are inherently unsafe)
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Old 03-22-2011, 08:27 PM   #30
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More good and accurate sanity in this article than in everything that has been blathered on TV altogether….

The info I referred to earlier:

Fukushima Nuclear Accident – a Simple and Accurate Explanation


13 March 2011 by Barry Brook

New 14 March: Updates and additional Q&A information here and Technical details here

Below I reproduce a summary on the situation prepared by Dr Josef Oehmen, a research scientist at MIT, in Boston. He is a PhD Scientist, whose father has extensive experience in Germany’s nuclear industry. This was first posted by Jason Morgan earlier this evening, and he has kindly allowed me to reproduce it here. I think it is very important that this information be widely understood.

Please also take the time to read this: An informed public is key to acceptance of nuclear energy * it was never more relevant than now.

***********

I am writing this text (Mar 12) to give you some peace of mind regarding some of the troubles in Japan, that is the safety of Japan’s nuclear reactors. Up front, the situation is serious, but under control. And this text is long! But you will know more about nuclear power plants after reading it than all journalists on this planet put together.

There was and will *not* be any significant release of radioactivity.

By “significant” I mean a level of radiation of more than what you would receive on – say – a long distance flight, or drinking a glass of beer that comes from certain areas with high levels of natural background radiation.

I have been reading every news release on the incident since the earthquake. There has not been one single (!) report that was accurate and free of errors (and part of that problem is also a weakness in the Japanese crisis communication). By “not free of errors” I do not refer to tendentious anti-nuclear journalism – that is quite normal these days. By “not free of errors” I mean blatant errors regarding physics and natural law, as well as gross misinterpretation of facts, due to an obvious lack of fundamental and basic understanding of the way nuclear reactors are build and operated. I have read a 3 page report on CNN where every single paragraph contained an error.

We will have to cover some fundamentals, before we get into what is going on.

Construction of the Fukushima nuclear power plants

The plants at Fukushima are so called Boiling Water Reactors, or BWR for short. Boiling Water Reactors are similar to a pressure cooker. The nuclear fuel heats water, the water boils and creates steam, the steam then drives turbines that create the electricity, and the steam is then cooled and condensed back to water, and the water send back to be heated by the nuclear fuel. The pressure cooker operates at about 250 C.

The nuclear fuel is uranium oxide. Uranium oxide is a ceramic with a very high melting point of about 3000 C. The fuel is manufactured in pellets (think little cylinders the size of Lego bricks). Those pieces are then put into a long tube made of Zircaloy with a melting point of 2200 C, and sealed tight. The assembly is called a fuel rod. These fuel rods are then put together to form larger packages, and a number of these packages are then put into the reactor. All these packages together are referred to as “the core”.

The Zircaloy casing is the first containment. It separates the radioactive fuel from the rest of the world.

The core is then placed in the “pressure vessels”. That is the pressure cooker we talked about before. The pressure vessels is the second containment. This is one sturdy piece of a pot, designed to safely contain the core for temperatures several hundred C. That covers the scenarios where cooling can be restored at some point.

The entire “hardware” of the nuclear reactor – the pressure vessel and all pipes, pumps, coolant (water) reserves, are then encased in the third containment. The third containment is a hermetically (air tight) sealed, very thick bubble of the strongest steel. The third containment is designed, built and tested for one single purpose: To contain, indefinitely, a complete core meltdown. For that purpose, a large and thick concrete basin is cast under the pressure vessel (the second containment), which is filled with graphite, all inside the third containment. This is the so-called “core catcher”. If the core melts and the pressure vessel bursts (and eventually melts), it will catch the molten fuel and everything else. It is built in such a way that the nuclear fuel will be spread out, so it can cool down.

This third containment is then surrounded by the reactor building. The reactor building is an outer shell that is supposed to keep the weather out, but nothing in. (this is the part that was damaged in the explosion, but more to that later).

Fundamentals of nuclear reactions

The uranium fuel generates heat by nuclear fission. Big uranium atoms are split into smaller atoms. That generates heat plus neutrons (one of the particles that forms an atom). When the neutron hits another uranium atom, that splits, generating more neutrons and so on. That is called the nuclear chain reaction.

Now, just packing a lot of fuel rods next to each other would quickly lead to overheating and after about 45 minutes to a melting of the fuel rods. It is worth mentioning at this point that the nuclear fuel in a reactor can *never* cause a nuclear explosion the type of a nuclear bomb. Building a nuclear bomb is actually quite difficult (ask Iran). In Chernobyl, the explosion was caused by excessive pressure buildup, hydrogen explosion and rupture of all containments, propelling molten core material into the environment (a “dirty bomb”). Why that did not and will not happen in Japan, further below.

In order to control the nuclear chain reaction, the reactor operators use so-called “control rods”. The control rods absorb the neutrons and kill the chain reaction instantaneously. A nuclear reactor is built in such a way, that when operating normally, you take out all the control rods. The coolant water then takes away the heat (and converts it into steam and electricity) at the same rate as the core produces it. And you have a lot of leeway around the standard operating point of 250C.

The challenge is that after inserting the rods and stopping the chain reaction, the core still keeps producing heat. The uranium “stopped” the chain reaction. But a number of intermediate radioactive elements are created by the uranium during its fission process, most notably Cesium and Iodine isotopes, i.e. radioactive versions of these elements that will eventually split up into smaller atoms and not be radioactive anymore. Those elements keep decaying and producing heat. Because they are not regenerated any longer from the uranium (the uranium stopped decaying after the control rods were put in), they get less and less, and so the core cools down over a matter of days, until those intermediate radioactive elements are used up.

This residual heat is causing the headaches right now.

So the first “type” of radioactive material is the uranium in the fuel rods, plus the intermediate radioactive elements that the uranium splits into, also inside the fuel rod (Cesium and Iodine).

There is a second type of radioactive material created, outside the fuel rods. The big main difference up front: Those radioactive materials have a very short half-life, that means that they decay very fast and split into non-radioactive materials. By fast I mean seconds. So if these radioactive materials are released into the environment, yes, radioactivity was released, but no, it is not dangerous, at all. Why? By the time you spelled “R-A-D-I-O-N-U-C-L-I-D-E”, they will be harmless, because they will have split up into non radioactive elements. Those radioactive elements are N-16, the radioactive isotope (or version) of nitrogen (air). The others are noble gases such as Xenon. But where do they come from? When the uranium splits, it generates a neutron (see above). Most of these neutrons will hit other uranium atoms and keep the nuclear chain reaction going. But some will leave the fuel rod and hit the water molecules, or the air that is in the water. Then, a non-radioactive element can “capture” the neutron. It becomes radioactive. As described above, it will quickly (seconds) get rid again of the neutron to return to its former beautiful self.

This second “type” of radiation is very important when we talk about the radioactivity being released into the environment later on.

What happened at Fukushima

I will try to summarize the main facts. The earthquake that hit Japan was 7 times more powerful than the worst earthquake the nuclear power plant was built for (the Richter scale works logarithmically; the difference between the 8.2 that the plants were built for and the 8.9 that happened is 7 times, not 0.7). So the first hooray for Japanese engineering, everything held up.

When the earthquake hit with 8.9, the nuclear reactors all went into automatic shutdown. Within seconds after the earthquake started, the control rods had been inserted into the core and nuclear chain reaction of the uranium stopped. Now, the cooling system has to carry away the residual heat. The residual heat load is about 3% of the heat load under normal operating conditions.

The earthquake destroyed the external power supply of the nuclear reactor. That is one of the most serious accidents for a nuclear power plant, and accordingly, a “plant black out” receives a lot of attention when designing backup systems. The power is needed to keep the coolant pumps working. Since the power plant had been shut down, it cannot produce any electricity by itself any more.

Things were going well for an hour. One set of multiple sets of emergency Diesel power generators kicked in and provided the electricity that was needed. Then the Tsunami came, much bigger than people had expected when building the power plant (see above, factor 7). The tsunami took out all multiple sets of backup Diesel generators.

When designing a nuclear power plant, engineers follow a philosophy called “Defense of Depth”. That means that you first build everything to withstand the worst catastrophe you can imagine, and then design the plant in such a way that it can still handle one system failure (that you thought could never happen) after the other. A tsunami taking out all backup power in one swift strike is such a scenario. The last line of defense is putting everything into the third containment (see above), that will keep everything, whatever the mess, control rods in our out, core molten or not, inside the reactor.

When the diesel generators were gone, the reactor operators switched to emergency battery power. The batteries were designed as one of the backups to the backups, to provide power for cooling the core for 8 hours. And they did.

Within the 8 hours, another power source had to be found and connected to the power plant. The power grid was down due to the earthquake. The diesel generators were destroyed by the tsunami. So mobile diesel generators were trucked in.

This is where things started to go seriously wrong. The external power generators could not be connected to the power plant (the plugs did not fit). So after the batteries ran out, the residual heat could not be carried away any more.

At this point the plant operators begin to follow emergency procedures that are in place for a “loss of cooling event”. It is again a step along the “Depth of Defense” lines. The power to the cooling systems should never have failed completely, but it did, so they “retreat” to the next line of defense. All of this, however shocking it seems to us, is part of the day-to-day training you go through as an operator, right through to managing a core meltdown.

It was at this stage that people started to talk about core meltdown. Because at the end of the day, if cooling cannot be restored, the core will eventually melt (after hours or days), and the last line of defense, the core catcher and third containment, would come into play.

But the goal at this stage was to manage the core while it was heating up, and ensure that the first containment (the Zircaloy tubes that contains the nuclear fuel), as well as the second containment (our pressure cooker) remain intact and operational for as long as possible, to give the engineers time to fix the cooling systems.

Because cooling the core is such a big deal, the reactor has a number of cooling systems, each in multiple versions (the reactor water cleanup system, the decay heat removal, the reactor core isolating cooling, the standby liquid cooling system, and the emergency core cooling system). Which one failed when or did not fail is not clear at this point in time.

So imagine our pressure cooker on the stove, heat on low, but on. The operators use whatever cooling system capacity they have to get rid of as much heat as possible, but the pressure starts building up. The priority now is to maintain integrity of the first containment (keep temperature of the fuel rods below 2200C), as well as the second containment, the pressure cooker. In order to maintain integrity of the pressure cooker (the second containment), the pressure has to be released from time to time. Because the ability to do that in an emergency is so important, the reactor has 11 pressure release valves. The operators now started venting steam from time to time to control the pressure. The temperature at this stage was about 550C.



This is when the reports about “radiation leakage” starting coming in. I believe I explained above why venting the steam is theoretically the same as releasing radiation into the environment, but why it was and is not dangerous. The radioactive nitrogen as well as the noble gases do not pose a threat to human health.

Last edited by sixshooter; 03-22-2011 at 09:03 PM.
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Old 03-22-2011, 08:27 PM   #31
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Continued:

At some stage during this venting, the explosion occurred. The explosion took place outside of the third containment (our “last line of defense”), and the reactor building. Remember that the reactor building has no function in keeping the radioactivity contained. It is not entirely clear yet what has happened, but this is the likely scenario: The operators decided to vent the steam from the pressure vessel not directly into the environment, but into the space between the third containment and the reactor building (to give the radioactivity in the steam more time to subside). The problem is that at the high temperatures that the core had reached at this stage, water molecules can “disassociate” into oxygen and hydrogen – an explosive mixture. And it did explode, outside the third containment, damaging the reactor building around. It was that sort of explosion, but inside the pressure vessel (because it was badly designed and not managed properly by the operators) that lead to the explosion of Chernobyl. This was never a risk at Fukushima. The problem of hydrogen-oxygen formation is one of the biggies when you design a power plant (if you are not Soviet, that is), so the reactor is built and operated in a way it cannot happen inside the containment. It happened outside, which was not intended but a possible scenario and OK, because it did not pose a risk for the containment.

So the pressure was under control, as steam was vented. Now, if you keep boiling your pot, the problem is that the water level will keep falling and falling. The core is covered by several meters of water in order to allow for some time to pass (hours, days) before it gets exposed. Once the rods start to be exposed at the top, the exposed parts will reach the critical temperature of 2200 C after about 45 minutes. This is when the first containment, the Zircaloy tube, would fail.

And this started to happen. The cooling could not be restored before there was some (very limited, but still) damage to the casing of some of the fuel. The nuclear material itself was still intact, but the surrounding Zircaloy shell had started melting. What happened now is that some of the byproducts of the uranium decay – radioactive Cesium and Iodine – started to mix with the steam. The big problem, uranium, was still under control, because the uranium oxide rods were good until 3000 C. It is confirmed that a very small amount of Cesium and Iodine was measured in the steam that was released into the atmosphere.

It seems this was the “go signal” for a major plan B. The small amounts of Cesium that were measured told the operators that the first containment on one of the rods somewhere was about to give. The Plan A had been to restore one of the regular cooling systems to the core. Why that failed is unclear. One plausible explanation is that the tsunami also took away / polluted all the clean water needed for the regular cooling systems.

The water used in the cooling system is very clean, demineralized (like distilled) water. The reason to use pure water is the above mentioned activation by the neutrons from the Uranium: Pure water does not get activated much, so stays practically radioactive-free. Dirt or salt in the water will absorb the neutrons quicker, becoming more radioactive. This has no effect whatsoever on the core – it does not care what it is cooled by. But it makes life more difficult for the operators and mechanics when they have to deal with activated (i.e. slightly radioactive) water.

But Plan A had failed – cooling systems down or additional clean water unavailable – so Plan B came into effect. This is what it looks like happened:

In order to prevent a core meltdown, the operators started to use sea water to cool the core. I am not quite sure if they flooded our pressure cooker with it (the second containment), or if they flooded the third containment, immersing the pressure cooker. But that is not relevant for us.

The point is that the nuclear fuel has now been cooled down. Because the chain reaction has been stopped a long time ago, there is only very little residual heat being produced now. The large amount of cooling water that has been used is sufficient to take up that heat. Because it is a lot of water, the core does not produce sufficient heat any more to produce any significant pressure. Also, boric acid has been added to the seawater. Boric acid is “liquid control rod”. Whatever decay is still going on, the Boron will capture the neutrons and further speed up the cooling down of the core.

The plant came close to a core meltdown. Here is the worst-case scenario that was avoided: If the seawater could not have been used for treatment, the operators would have continued to vent the water steam to avoid pressure buildup. The third containment would then have been completely sealed to allow the core meltdown to happen without releasing radioactive material. After the meltdown, there would have been a waiting period for the intermediate radioactive materials to decay inside the reactor, and all radioactive particles to settle on a surface inside the containment. The cooling system would have been restored eventually, and the molten core cooled to a manageable temperature. The containment would have been cleaned up on the inside. Then a messy job of removing the molten core from the containment would have begun, packing the (now solid again) fuel bit by bit into transportation containers to be shipped to processing plants. Depending on the damage, the block of the plant would then either be repaired or dismantled.

Now, where does that leave us?

  • The plant is safe now and will stay safe.
  • Japan is looking at an INES Level 4 Accident: Nuclear accident with local consequences. That is bad for the company that owns the plant, but not for anyone else.
  • Some radiation was released when the pressure vessel was vented. All radioactive isotopes from the activated steam have gone (decayed). A very small amount of Cesium was released, as well as Iodine. If you were sitting on top of the plants’ chimney when they were venting, you should probably give up smoking to return to your former life expectancy. The Cesium and Iodine isotopes were carried out to the sea and will never be seen again.
  • There was some limited damage to the first containment. That means that some amounts of radioactive Cesium and Iodine will also be released into the cooling water, but no Uranium or other nasty stuff (the Uranium oxide does not “dissolve” in the water). There are facilities for treating the cooling water inside the third containment. The radioactive Cesium and Iodine will be removed there and eventually stored as radioactive waste in terminal storage.
  • The seawater used as cooling water will be activated to some degree. Because the control rods are fully inserted, the Uranium chain reaction is not happening. That means the “main” nuclear reaction is not happening, thus not contributing to the activation. The intermediate radioactive materials (Cesium and Iodine) are also almost gone at this stage, because the Uranium decay was stopped a long time ago. This further reduces the activation. The bottom line is that there will be some low level of activation of the seawater, which will also be removed by the treatment facilities.
  • The seawater will then be replaced over time with the “normal” cooling water
  • The reactor core will then be dismantled and transported to a processing facility, just like during a regular fuel change.
  • Fuel rods and the entire plant will be checked for potential damage. This will take about 4-5 years.
  • The safety systems on all Japanese plants will be upgraded to withstand a 9.0 earthquake and tsunami (or worse)
  • I believe the most significant problem will be a prolonged power shortage. About half of Japan’s nuclear reactors will probably have to be inspected, reducing the nation’s power generating capacity by 15%. This will probably be covered by running gas power plants that are usually only used for peak loads to cover some of the base load as well. That will increase their electricity bill, as well as lead to potential power shortages during peak demand, in Japan.

If you want to stay informed, please forget the usual media outlets and consult the following websites:

http://www.world-nuclear-news.org/RS...s_1203111.html
http://bravenewclimate.com/2011/03/1...ar-earthquake/

http://ansnuclearcafe.org/2011/03/11...ions-in-japan/

Last edited by sixshooter; 03-22-2011 at 09:04 PM.
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Old 03-22-2011, 09:19 PM   #32
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good ****.
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Old 03-23-2011, 01:50 AM   #33
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Originally Posted by JasonC SBB View Post
I would love to see a net comparison of nuclear and coal- deaths and shortened lives PER TERAWATT-HOUR GENERATED due to radiation, air pollution, and mining, including 3 Mile Island and Fukushima
It may be a while before we have reliable data on Fuku, but it looks like some people have already compiled the exact data of which you speak- deaths per TWh.

Energy Source Death Rate (deaths per TWh)

Coal – world average 161 (26% of world energy, 50% of electricity)
Coal – China 278
Coal – USA 15
Oil 36 (36% of world energy)
Natural Gas 4 (21% of world energy)
Biofuel/Biomass 12
Peat 12
Solar (rooftop) 0.44 (less than 0.1% of world energy)
Wind 0.15 (less than 1% of world energy)
Hydro 0.10 (europe death rate, 2.2% of world energy)
Hydro - world including Banqiao) 1.4 (about 2500 TWh/yr and 171,000 Banqiao dead)
Nuclear 0.04 (5.9% of world energy)
(source: http://nextbigfuture.com/2008/03/dea...y-sources.html )

Hmm. Rooftop solar is 10 times more dangerous than nuclear. Makes sense- not many people trip and fall from the tops of nuclear plants.

Wind is pretty lethal, too.

Here's another report from an EU think tank which shows the same basic trends, looking only at European nations: http://manhaz.cyf.gov.pl/manhaz/stro...20Polenp~1.pdf

From the above-linked report:



(Apparently in the EU, nuclear is more dangerous than hydro. Still far safer than wind power, though.)



Brainey also posted this chart earlier in the thread, though no source was given, the data seems very close to the overall worldwide figures in the first table I posted above:





But you're right. I have yet to see anything which suggests that nuclear power comes within even a few orders of magnitude of fossil fuels in terms of deaths per unit of energy generated.



Lewis Page, of The Register (a UK paper) puts this all into perspective:
The Fukushima reactors actually came through the quake with flying colours despite the fact that it was five times stronger than they had been built to withstand. Only with the following tsunami – again, bigger than the design allowed for – did problems develop, and these problems seem likely to end in insignificant consequences. The Nos 1, 2 and 3 reactors at Daiichi may never produce power again – though this is not certain – but the likelihood is that Nos 4, 5 and 6 will return to service behind a bigger tsunami barrier.

The lesson to learn here is that if your country is hit by a monster earthquake and tsunami, one of the safest places to be is at the local nuclear powerplant. Other Japanese nuclear powerplants in the quake-stricken area, in fact, are sheltering homeless refugees in their buildings – which are some of the few in the region left standing at all, let alone with heating, water and other amenities.

Nothing else in the quake-stricken area has come through anything like as well as the nuclear power stations, or with so little harm to the population. All other forms of infrastructure – transport, housing, industries – have failed the people in and around them comprehensively, leading to deaths most probably in the tens of thousands. Fires, explosions and tank/pipeline ruptures all across the region will have done incalculably more environmental damage, distributed hugely greater amounts of carcinogens than Fukushima Daiichi – which has so far emitted almost nothing but radioactive steam (which becomes non-radioactive within minutes of being generated).

And yet nobody will say after this: "don't build roads; don't build towns; don't build ships or chemical plants or oil refineries or railways". That would be ridiculous, of course, even though having all those things has actually led to terrible loss of life, destruction and pollution in the quake's wake.

But far and away more ridiculously, a lot of people are already saying that Fukushima with its probable zero consequences means that no new nuclear powerplants should ever be built again.



Quote:
Originally Posted by Oscar View Post
No, seriously Joe. Why?
Honestly, I'm no genius. There's a hell of a lot about nuclear physics that I will never understand. I just read a lot. Some people are fascinated by the history of warfare, some by the history of stamps, personally, I am fascinated by the evolution of modern technology and, specifically, man-machine interaction. How do people use technology, that sort of thing.

There are a number of specific fields which I find rich in this regard. The evolution of modern computing is one- specifically the area of the late 1950s (the first solid-state computers and the first interactive computers) through the 1960s (the dawn of networking) and into the 1970s (the rise of the PC). The telephone system and the national power grid are other systems that are hugely interesting- massively complex and yet highly reliable and almost infinitely scalable.

And then, of course, there's nuclear power. The design and operation of reactors is a really rich field of study. And when things go really wrong at them, you get an almost totally unique glimpse into the most fundamental tenets of things like fault tolerance, design-for-reliability, and the intelligibility of complex systems (how do you make something very complicated very easy to use, especially under stressful conditions when seemingly contradictory information presents itself?)

TMI, to me, is still the seminal example here. So many mistakes were made, by so many people. There were design flaws, like instrumenting valves in ambiguous ways and placing instruments in locations which made it had to correlate data between them. There were poor decisions made in the configuration of the system. Seemingly simple choices, like standardizing on a common fitting for all air and water lines inside the turbine hall probably seemed like a good idea to somebody, but it's what made it possible for some maintenance worker to accidentally blow water into the instrument air system, which was what set the whole chain of events in motion. Flow valves were configured to fail closed, rather than failing in their last-known state. Assumptions made about how the ECCS would work which all went down the drain when somebody closed a service valve and forgot to re-open it.

Really fascinating stuff...
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Old 03-23-2011, 12:17 PM   #34
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Great info Sixshooter and Joe. Sixshooter do you mind that I forward that info to my not so informed and badwagoner co-workers and friends?
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Old 03-23-2011, 03:01 PM   #35
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Thanks for posting! It's nice to get a point of view other than the media's sensationalized reporting.
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Old 03-23-2011, 09:43 PM   #36
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Great info Sixshooter and Joe. Sixshooter do you mind that I forward that info to my not so informed and badwagoner co-workers and friends?
Please share it.
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Old 03-23-2011, 10:38 PM   #37
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I wonder now how radiation released by Fukushima and TMI and all the other non-Soviet reactors compares to coal, per TW-h generated. Half life has to be included as a factor...

Perhaps # of lives lost including years shortened and pro-rated (by cancer, lung disease, etc) per TW-h too. e.g. if someone dies at 38 due to coal pollution, that would count as 0.5 life lost (assumes 76 year avg lifespan).
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Old 03-23-2011, 11:15 PM   #38
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please provide your answers in the units of Banana Equivalent Dose.
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Old 03-24-2011, 09:31 AM   #39
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Not that I believe anything thats printed in Businessweek, but they are saying Germany is done with nuclear power.

http://www.businessweek.com/ap/finan.../D9M4U7300.htm
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Old 03-24-2011, 09:43 AM   #40
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I'm Pro-Nuke, because the numbers (demand vs supply) just don't work without it as oil moves to $500 a barrel.

However, I don't want nuke plants operated by for profit companies. My preference would be to have them run by not-for-profits, with their only goal being safe operation. Or, nationalize the plants and let the military run them.

Why?

Because the profit motive makes them inherently unsafe. An example is Entergy corporation who operates VT Yankee. Every single decision that company has made has been for profit at the expense of safety.
Here's a quick hit list:
1. At the end of the plants design life, they asked, and received permission to run the plant at 126% of it's design max. This increases the radiation exposure to the adjacent middle school (although it's still quite low).
2. They asked to take the money they were required to save to decommission the plant, and distribute it to share holders as profit.
3. They asked to take the money they were required to save to deal with spent fuel rods and distribute that to share holders as profit.
4. They were told to inspect their cooling towers, because this design has been failing as it ages. They said they did it. They lied. The cooling tower collapsed.
5. The external monitoring wells exposed a tritium leak. They lied about the design of the plant, stating that no piping went underground, when they knew it did. They continued to operate the plant, as the tritium continued to leak into the ground from an underground pipe.

Profit makes companies make socially bad decisions.
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