Thank You Amber G. Yes a 85 MWe reactor has a much lower cooling requirement than a 1000 MWe one.Amber G. wrote:1. Power requirement are much smaller. (Much smaller size, and LOCA requirements are much smaller)
2011 Japanese Earthquake and Tsunami - News and Analysis
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
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Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
Amber G,
I can see it now. The EBs are going to scream about how unsafe the Arihant and the NERPA are and the massive radiation ecological disaster it will cause.
Please send Rakesh bhai's mithai to me. After all, its made with irradiated milk!
I can see it now. The EBs are going to scream about how unsafe the Arihant and the NERPA are and the massive radiation ecological disaster it will cause.
Please send Rakesh bhai's mithai to me. After all, its made with irradiated milk!
Last edited by Mort Walker on 13 Apr 2011 06:55, edited 1 time in total.
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Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
I was hoping that in all of this discussion of batteries, UPS systems and EGs, that somebody(hint: the anti-nuke EBs) would have mentioned fuel cells as a back up power source in the event of an emergency. Kind of like the 120 KWe fuel cells on the HDW Type 212 U-Boats. Seems like the ideal application.
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Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
How Fukushima is and isn't like Chernobyl - April 12, 2011
http://blogs.nature.com/news/thegreatbe ... ike_1.html
Radiation release will hit marine life: Researchers call for extensive surveys to gauge ecological effects of Fukushima.
http://www.nature.com/news/2011/110412/ ... 2145a.html
http://blogs.nature.com/news/thegreatbe ... ike_1.html
This morning, the Japanese government officially upgraded Fukushima on the International Nuclear Events Scale to a 7, or "Major accident". The new rating is the highest on the scale, and puts Fukushima on a par with the worst nuclear accident in history—Chernobyl. Understandably, the press has made quite a big deal out of new rating, but the reality is that Fukushima is a very different accident than Chernobyl.
The maps on the right do show a passing similarity between the two accidents. The top one shows overflight measurements of radiation in the region around Fukushima. The bottom one shows Caesium-137 measurements from Chernobyl. The data are not completely analogous, but I think the maps give a sense of how both accidents have contaminated large areas and created regional hotspots that will require additional evacuations.
But there are very important differences between Fukushima and Chernobyl. The biggest, in my mind at least, is the timescale over which the accident occurred. When Chernobyl's reactor number 4 exploded in 1986, it scattered debris over a wide area and sent radioactive fallout high into the atmosphere. Entire villages near the reactor had to be evacuated in a matter of hours, and many residents had to leave personal effects behind. A fire burned at the site until 5 May, spewing tones of radioactive material over 200,000 square kilometres. By November, workers had successfully completed a concrete sarcophagus around the core, effectively sealing it off. In the short period following the explosion, the accident spewed some 14 million terabecquerels of radiation into the environment.
The Fukushima accident has unfolded much more slowly. The damaged reactors exploded over a period of days, and after a modest initial release, radiation has fallen off. So far, the reactors have spread about half-a-million terabecquerels into the air. I haven't been able to find hard data on the first month after Chernobyl, but I'm willing to bet my lunch that it put out a lot more in that period.
The problem is that Fukushima's slow bleed of radiation is going to continue for a good period of time to come. Reactors are normally kept cool by recirculated water, but at Fukushima, the circulation system has been heavily damaged, and the only solution is to simply dump tons of water onto the cores. The water absorbs radioactive isotopes like caesium-137, and itself becomes a big waste problem. Moreover pictures from as recently as 10 April show steam continuing to rise from the reactors.
This seepage in the form of water, dust and steam is creating slow-motion Chernobyl at Fukushima Daiichi. Yesterday the government announced evacuations from several villages outside the current exclusion zone. Unlike the dramatic evacuations from the Chernobyl reactors, these will take place slowly over a matter of a month or so. That's because radiation levels in the region are low enough to be safe in the near term, but not in the long-term. As ground-contamination data continues to be collected, I suspect we'll see more localized evacuations over the coming weeks and possibly even months.
Time is important, especially in nuclear accidents. Fukushima's slower burn makes it easier for officials to respond to radiation risks and protect the population from contaminated food, water and air. Yet the slow release of radiation into the environment could still have great long-term economic and environmental consequences. As we've just written, the clean-up of Fukushima will probably resemble Chernobyl in many ways, and could take longer.
Radiation release will hit marine life: Researchers call for extensive surveys to gauge ecological effects of Fukushima.
http://www.nature.com/news/2011/110412/ ... 2145a.html
As radioisotopes pour into the sea from the crippled Fukushima Daiichi nuclear plant, one reassuring message has been heard over and over again: the Pacific Ocean is a big place.
That the isotopes will be vastly diluted is not in question. Nevertheless, scientists are calling for a marine survey to begin as soon as possible to assess any damage to ecosystems in the area around Fukushima. Although the contamination is unlikely to cause immediate harm to marine organisms, long-lived isotopes are expected to accumulate in the food chain and may cause problems such as increased mortality in fish and marine-mammal populations.
"Just because you can measure it, doesn't mean it's dangerous," says Ken Buesseler, a marine geochemist at the Woods Hole Oceanographic Institution in Massachusetts. "Even so, this is the biggest man-made release ever of radioactive material into the oceans. We haven't yet seen enough data to assess what's going on, so anything that can be done in terms of further monitoring would be very welcome."
The past two weeks have seen extremely high concentrations of radioactive iodine-131 (with a half life of 8 days) and caesium-137 (which has a half life of 30 years) in samples of sea water collected near the Fukushima reactors, and even as far as 30 kilometres offshore. By late March, levels were tens of thousands of times higher than before the accident (see 'Radioisotope contamination'). Many other radioisotopes, both long- and short-lived, are also likely to have been released.
But the total amount of radioactivity that has entered the ocean is unknown, and discharges — both accidental and deliberate — are continuing and may even be substantial if any further problems occur at the Fukushima plant (see page 146).
Despite these uncertainties, scientists at the National Institute of Radiological Sciences (NIRS) in Chiba, Japan, are designing studies aimed at monitoring the accumulation of radionuclides in the muscles, organs, eggs and bones of marine organisms. They also plan to model the long-term behaviour of radioisotopes in the marine environment, and the overall radiation doses to which marine organisms will be exposed. "We need to obtain specific concentrations of caesium and iodine isotopes to assess their effects in different marine organisms," says Tatsuo Aono, an expert in marine radioecology at the NIRS.
A team led by Dominique Boust, director of the French Institute of Radioprotection and Nuclear Safety (IRSN) in Cherbourg, is now predicting the level of contamination in marine organisms and sediments using estimates of the quantity of radioisotopes released from Fukushima, and the ratios of those isotopes calculated from available seawater measurements.
The team calculates that about 50 radioisotopes contribute to an overall concentration of roughly 10,000 becquerels per litre in the sea water within 300 metres of Fukushima. Before the accident, caesium-137 concentrations there were about 0.003 becquerels per litre, and iodine-131 was not detectable. On the basis of these figures, the IRSN researchers suggest that sediments in the region could now contain 10,000–10 million becquerels per kilogram; fish could carry 10,000–100,000 becquerels per kilogram; and algae, some of which are particularly susceptible to iodine uptake, could contain up to 100 million becquerels per kilogram. Japan has legal limits of radioactivity in fish for human consumption of 500 becquerels per kilogram for caesium-137, and 2,000 becquerels per kilogram for iodine-131.
"Doses will decrease very quickly with time and distance from the facility, if no further leaks occur, but there could remain a persistent low-dose component in the local marine environment for many years," says Thomas Hinton, deputy director of the IRSN's Laboratory of Radioecology, Ecotoxicology and Environmental Modelling in Cadarache, France. "The impacts are best addressed through an international long-term assessment."
Ward Whicker, an environmental and radiological health expert at Colorado State University in Fort Collins, agrees that a survey would be worthwhile. "It would require a great deal of sampling effort, near the discharge point as well as at locations farther away," he says. "Concentrations of radionuclides in water, sediments, plankton, molluscs, crustaceans, seaweed and fish would need to be measured, and the health of the ecosystem monitored."
Although radioisotope concentrations in fish, shellfish and seaweed could exceed limits for human consumption for weeks, Whicker thinks that it is unlikely that scientists would be able to detect any genetic effects on marine life. Any affected creatures would probably disperse into the Pacific, or die more quickly, he says. Moreover, teasing out radiological effects from other stresses, such as conventional water pollution and the damage caused by the tsunami, would be extremely difficult.
An alternative approach could be to focus on a suitable proxy species. "In my opinion, brown seaweed should be the number one research priority," says Bruno Fievet, a radioecologist at the IRNS in Cherbourg. The brown seaweed Laminaria digitata, ubiquitous in the coastal Pacific waters off Japan, absorbs iodine to help defend itself against environmental stresses such as pollution. It can have iodine concentrations some 10,000 times greater than the surrounding sea water. "This species is the world champion in iodine uptake, and it would be a good indicator of the radioactive labelling of other marine organisms," says Fievet.
But sampling may be hampered by the danger that remains at the Fukushima plant. "Any survey would be welcome," says Ulf Riebesell, a biological oceanographer at the Leibniz Institute of Marine Sciences in Kiel, Germany. "But I certainly wouldn't ask my students to do field work off Japan amid this ongoing crisis."
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Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
Japan faces power struggle: Climate goals in doubt as fossil fuels come to the fore in fight to meet electricity demand.
http://www.nature.com/news/2011/110412/ ... 2143a.html
http://www.nature.com/news/2011/110412/ ... 2143a.html
The disaster at Japan's Fukushima nuclear power plant is putting the nation's ambitious plans to reduce carbon emissions under serious pressure. With few natural resources, Japan has long been forced to rely on imports of oil, coal and natural gas to provide about 80% of the energy needed to sustain its economy. Nuclear energy was supposed to help Japan limit these energy imports and cut its carbon emissions at the same time — but that was before Fukushima.
The government has committed to reduce carbon emissions by 25% from 1990 levels by 2020, and by roughly 80% from 1990 levels by 2050. The short-term target is particularly ambitious, because Japan's streamlined economy is already among the most energy-efficient in the world. To achieve its goals, Japan had planned to build nine nuclear power plants over the coming decade and a total of 14 plants by 2030, all while squeezing as much power as possible out of the current 54 plants. By 2030, nuclear power was to have provided half of Japan's electricity, doubling its current contribution (see 'Nuclear power in Japan').
A big question mark now hangs over those plans. Nearly a month after the magnitude-9.0 earthquake and the tsunami that followed, workers are still struggling to control the reactors at Fukushima. Four of the six reactors there have been destroyed; the other two will probably never run again; and plans for two new reactors have been abandoned (see page 146). Another eight reactors in the northwest of the country were automatically shut down after the 11 March earthquake. The Tokyo Electric Power Company (TEPCO), Japan's largest private utility, which operates Fukushima Daiichi and three other nuclear plants with multiple reactors, is struggling to meet electricity demand in Tokyo. Japan's vulnerability was highlighted again on 7 April, when a magnitude-7.1 earthquake temporarily shut down several conventional power stations and left millions without electricity.
No one knows when the situation will stabilize, nor what Japan's nuclear industry will look like when it does. Although several power firms say they will stick to construction schedules to meet the nuclear capacity goals, the Japanese government has ordered a review of its energy policy. "They obviously have a predicament in that they have put a lot of eggs in the nuclear-power basket," says Ed Lyman, a nuclear expert with the Union of Concerned Scientists in Washington DC. "It's hard to imagine that Fukushima isn't going to disrupt those plans."
The most immediate challenge is to meet the nation's electricity needs. The rolling blackouts introduced after the crisis began have stopped, thanks to reduced demand and energy conservation measures. But supplying enough power is difficult because Japan maintains two essentially incompatible electricity grids, a decision dating back more than a century. These grids carry alternating current at different frequencies, preventing large-scale diversion of electricity from power plants outside the affected region. There are no plans to unify the systems.
In the short term, most experts agree that the crisis will force Japan to rely much more heavily on its natural-gas power stations, and potentially also its coal-fired plants. But increasing fossil-fuel use probably won't stop Japan from meeting its short-term carbon-emissions commitment under the Kyoto Protocol — a reduction of 6% below 1990 levels by 2012 — says Lisa Zelljadt, a senior analyst with the energy consultancy Thompson Reuters Point Carbon in Washington DC.
Japan's emissions have increased significantly since 1990, so the country has been working to offset much of its emissions by paying for reductions in other countries. "The only way that they were going to make their Kyoto commitments was by buying carbon credits," says Robert Stavins, an economist at Harvard University in Cambridge, Massachusetts. Japan also moved a little closer towards its climate targets during the global economic crisis, when plunging economic output reduced emissions by 7% from 2007 to 2008. The earthquake, tsunami and nuclear crisis will also help curb carbon output.
All these factors should put Japan in a position to meet its Kyoto commitments, says Zelljadt. "The nuclear disaster will thus affect more how Japan stands towards a longer-term target in the international negotiations," she says.
In a move towards not just carbon-free energy but also energy self-sufficiency, Japan had outlined ambitious plans to develop an advanced nuclear-energy programme that would not only recycle spent nuclear fuel but also deploy fast-breeder reactors that produce more fuel than they burn (see Nature 464, 661; 2010).
These efforts are a cornerstone of Japan's climate strategy, but they were under pressure even before the earthquake. Japan's Rokkasho reprocessing plant has suffered from numerous problems and will be some 15 years behind schedule if it opens as currently planned in 2012. The plant stores thousands of tonnes of spent nuclear fuel, and had to rely on backup diesel generators to cool the fuel after the plant lost power following last week's big aftershock.
Meanwhile, a prototype fast-breeder reactor — dubbed Monju — has been plagued with problems (see Nature 434, 6; 2005). Fifteen years after a sodium coolant leak and a related fire led to its closure, Monju was briefly started up in 2010 only to be shut down once again after a non-nuclear accident.
"It's a pretty grim story anywhere you look in Japan," says Lyman. "You have to wonder how many nuclear failures they can put up with before throwing in the towel."
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
For perspective (Total amount released rough values)
Chernobyl: 1800 PBq of I131 and 85 PBq of C137
Fukushima: 130 PBq (NISA) I131; 6.1 PBq (NISA) C137
Chernobyl: 1800 PBq of I131 and 85 PBq of C137
Fukushima: 130 PBq (NISA) I131; 6.1 PBq (NISA) C137
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Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
AmberG's graph on the decay heat is pretty instructive. From what I read up after Fukushima, if a plant has been running at full power for 100 days or so, the decay heat at shutdown is 7% of full power. It starts decaying exponentially and in a few hours is down to half and in some 3 days after shutdown is something like 0.2% of full power rating! Now for a 1000 Mwe ~ 3000 MWT (at 33% thermodynamic efficiency), the heat that gets generated long term is 0.2% * 3000 = 6MW! Now what will you size your boiler and other systems for ? The 7% ~ 210MW at shutdown or the 0.2 % long term ? And yeah, in any power plant (coal, gas, Nookeleyar etc), the feed water pumps are pretty large and consume the order of 3% to 5% the OUTPUT of the plant itself. So , if you think that the 6MW(T) waste heat (in say a cooling pond outside) is going to generate the order of 30MWe to 50MWe to power the circulating pumps, as Mr Spock said in Star Trek , It Doesn't Compute!Lalmohan wrote:so, if i understand correctly, the heat in the spent rod pool is exponentially decaying and apart from some short term heat exchange, is not of much use?

Well, usually ,there will be recuperators and other stuff in the inlet side of the boiler , that gets heated by the kind of Paani you are talking about, so that feed it is not water at ambient (which can be ice cold in places ) that goes into the boiler, but rather much warmer and hence cutting down on the fuel needed .. This is basically capturing heat that would have gone "waste" otherwise. So yeah, you use that to increase plant efficiency.however, the heat from the main cooling circuits, post turbine work, i assume can still be used via heat exchanger for district heating type applications?
Some of the best use of that kind of low grade heat is ironically in cooling/ A/c using Absorption Chillers /Coolers (google for it or better still, ask our expert Chaanakya , who drops BIG BIG words like "Rankine cycle" about it), which is probably one of the most efficient methods of cooling . So ,if you are in a process industry, with low grade heat, that kind of system for airconditioning and chilling is simply superb. I think in Yindia, Thermax makes such stuff IIRC.
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Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
There are Fluidized Bed Boilers (google for it), which do precisely that and the efficiency increase comes from going combined cycle, the coal gas is first used to drive a Gas Turbine , the outlet of which drives a steam cycle, raising the total efficiency above 51% , sometime approaching 60% for the overall system!.GuruPrabhu wrote: Waste heat from coal plants can be used to steam coals into gas (clean coal) and re-burn it -- by some accunts it raises thermal efficiency from ~33% to ~50%. Ityadi, ityadi.
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
Funnily enough, only ones making such remarks on behalf of others are nuclear at all costs NOW lobby.Mort Walker wrote:Amber G,
I can see it now. The EBs are going to scream about how unsafe the Arihant and the NERPA are and the massive radiation ecological disaster it will cause.
Please send Rakesh bhai's mithai to me. After all, its made with irradiated milk!
Non partisan folks see all sides of a issue.
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Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
Lalmohan was taking about *spent fuel* tank. Amber.s graph is for reactor tank.vina wrote:AmberG's graph on the decay heat is pretty instructive. From what I read up after Fukushima, if a plant has been running at full power for 100 days or so, the decay heat at shutdown is 7% of full power.Lalmohan wrote:so, if i understand correctly, the heat in the spent rod pool is exponentially decaying and apart from some short term heat exchange, is not of much use?
Lalmohan never said anything about "30-50 MW", did he? I may have missed it so please correct me.So , if you think that the 6MW(T) waste heat (in say a cooling pond outside) is going to generate the order of 30MWe to 50MWe to power the circulating pumps, as Mr Spock said in Star Trek , It Doesn't Compute!
In your enthusiasm to expound on kanoon of therm-o-djinnamics, you are shooting from the hip at all and sundry.
Last edited by GuruPrabhu on 13 Apr 2011 09:52, edited 1 time in total.
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Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
chaanakya wrote:Ammonia is one fluid, but obviously not suitable for Indian or even Fukushima Situation as you pointed out..


Huh! I am gob smacked! The earliest refrigerators were Ammonia cycle ones! They ran perfectly well ALL around the world including India of course!
Why, when I R2I ed to India, I went and bought up a Godrej refrigerator, which has a sticker which proudly announced that it is India's only "100% CFC, HFC & HCFC Free Refrigerator" . The PentaCool series. Yeah, it uses Pentane. Hydrocarbons such as CH4, Butane, Pentane like Ammonia were "traditional" working fluids until CFCs became popular!
And now , now if you are going to say, I was talking of Turbines, while you are talking of Refrigerators, it is because of this.
Guruji, Aapke charan kahan hai? Choone dijiye! You must be unique kind of guy who while learning driving must have learnt driving in REVERSE, before driving in the forward gears ! How else would you know about the Rankine Cycle which is the Reverse Carnot Cycle , before knowing Carnot Cycle and stuff like Sensible Heat!But you are not far off the mark. Rankine Cycle may ring a bell. You would be knowing better about these turbines. Check NAL.
But Guruji, ghanti tho bhaj rahi hai, but for fridges and heat pumps with Rankine cycle. But.. butt .. you are talking about Turbines and I thought they worked on Brayton cycles!


Also we are not talking of multi MW type power output.
Pliss to refer to the Madrassa math in my earlier bosht!
Public! What technology and worked where? I am clueless. Please enlighten usI would say it is working and has worked in few places. Though not all details are public, technology is fairly well known.
indeed there is. It is one thing to be ignorant of something, but another thing altogether to have the chutzpah to wing it via FUD and other obfuscation and dodging and other dodgy stuff!Might not be very cost efficient. if NPPs have not gone for it , there must be some other issue.
On the contrary, this is very relevant and goes to the HEART of why Fukishima happened. Remember, Fukushima was NOT a NUCLEAR accident like Chernobyl was (where there was an uncontrolled chain reaction) , but daal-chaawal engineering failure of heat removal systems, which is very Non Nuclear engineering failure! So talking about heat transfer is the the thing of most relevance here!Anyway , that is OT here and was in response to Lalmohan.
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
GP I think you know that but though the graph was shown for the reactor, decay heat in spent fuel essentially follows the same graph. In both cases decay heat comes from fuel's (fission product's) radioactivity. (Different isotopes with varying half-life and activity gives that kind of graph)
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Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
Amber, the difference is that there is no "exponential" part and then some other type of part. It is a convolution of N exponentials where N is the number of isotopes present. As I posted to Lalmohan, once we are past the short lived ones, it can easily be approximated as linear and for the most part a steady state heat source in the short term (as the latter part of your graph suggests). So, the applicable graph for the spent fuel is only the tail of the distribution shown in your graph.
(Added later: I think we are saying the same thing)
(Added later: I think we are saying the same thing)
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
The lack of transparency coupled with issuing statements which went against every grain of common sense (followed by contradiction after two weeks) have created a culture of distrust.
http://www.reuters.com/article/2011/04/ ... 1020110413
Nuclear fears keep shippers wary of travel to Japan
Japan's nuclear evacuees shunned over health fears
http://www.reuters.com/article/2011/04/ ... 1020110413
Nuclear fears keep shippers wary of travel to Japan
http://www.hindustantimes.com/RestOfAsi ... 84614.aspxSINGAPORE, April 13 (Reuters) - Foreign crew members remain hesitant to travel near Japan's quake-crippled nuclear plant, including to some ports outside the exclusion zone, forcing shippers to use Japanese vessels instead to transport goods, senior industry executives said.
Japan's nuclear evacuees shunned over health fears
People fleeing Japan's crippled nuclear plant are being turned away from evacuation centres because of unfounded fears they might contaminate others with radiation. Those made homeless by the emergency at the stricken Fukushima Daiichi atomic plant need local government-issued certificates proving they are not contaminated before they are allowed to step foot inside the centres.
Screening facilities set up to soothe concerns over radiation have become checkpoints that determine access to a place to sleep and -- in at least one case -- healthcare, even though experts say evacuees pose no risk to others.
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
http://www.reuters.com/article/2011/04/ ... 6520110413China nuclear watchdog says Japan crisis no Chernobyl
"Its impact on our country's environment has been small, equivalent to about one percent of the impact of the Chernobyl nuclear accident on our country," said the ministry.
"There is no need to adopt protective measures."
http://www.reuters.com/article/2011/04/ ... UC20110412Analysis: After Japan, nuclear accident ratings reform sought
"Fukushima was not as bad as Chernobyl. If Fukushima is a level 7 accident, maybe we need to go back and recalibrate the scale and add a level 8 or 9," said Najmedin Meshkati, Professor of Civil and Environmental Engineering at the University of Southern California.
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Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
Here's and interesting link. I think Amber posted something similar:
Risks from reactor accidents are estimated by the rapidly developing science of "probabilistic risk analysis" (PRA). A PRA must be done separately for each power plant (at a cost of $5 million) but we give typical results here: A fuel melt-down might be expected once in 20,000 years of reactor operation. In 2 out of 3 melt-downs there would be no deaths, in 1 out of 5 there would be over 1000 deaths, and in 1 out of 100,000 there would be 50,000 deaths. The average for all meltdowns would be 400 deaths. Since air pollution from coal burning is estimated to be causing 10,000 deaths per year, there would have to be 25 melt-downs each year for nuclear power to be as dangerous as coal burning.
Of course deaths from coal burning air pollution are not noticeable, but the same is true for the cancer deaths from reactor accidents. In the worst accident considered, expected once in 100,000 melt-downs (once in 2 billion years of reactor operation), the cancer deaths would be among 10 million people, increasing their cancer risk typically from 20% (the current U.S. average) to 20.5%. This is much less than the geographical variation--- 22% in New England to 17% in the Rocky Mountain states.
Very high radiation doses can destroy body functions and lead to death within 60 days, but such "noticeable" deaths would be expected in only 2% of reactor melt-down accidents; there would be over 100 in 0.2% of meltdowns, and 3500 in 1 out of 100,000 melt-downs. To date, the largest number of noticeable deaths from coal burning was in an air pollution incident (London, 1952) where there were 3500 extra deaths in one week. Of course the nuclear accidents are hypothetical and there are many much worse hypothetical accidents in other electricity generation technologies; e.g., there are hydroelectric dams in California whose sudden failure could cause 200,000 deaths.
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Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
Another interesting document.
According to a Lancet Study in 2007, compared with nuclear power, coal is responsible for five times as many worker deaths from accidents, 470 times as many deaths due to air pollution among members of the public, and more than 1,000 times as many cases of serious illness, according to a study of the health effects of electricity generation in Europe.
In “Full cost accounting for the life cycle of coal,” published this year by a team of 12 researchers led by Paul R. Epstein of Harvard Medical School’s Center for Health and the Global Environment, the ledger included .02 cents per kilowatt hour for mental retardation caused by mercury in coal-plant emissions.
Using similar methods, Markandya and his co-author in the Lancet study, Paul Wilkinson of the London School of Hygiene and Tropical Medicine, found that in Europe coal is responsible for .12 deaths from accidents, 25 deaths from pollution and 225 cases of serious illness per terawatt (1,000 billion kilowatt) hour of electricity generated. In comparison, nuclear causes .02 accidental deaths, .05 pollution deaths and .22 cases of illness.
It’s especially high in China, where three-quarters of the electricity is made by burning coal, mining accidents kill about 6,000 people a year, and hundreds of millions of people are affected by air pollution. In some inland cities, the economic cost to human health of making electricity from coal is as much as seven times higher than the cost of generating the electricity, according to a calculation by Stefan Hirschberg at the Paul Scherrer Institutin Switzerland, which has done energy system analysis for the European Commission.
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
http://www.japantoday.com/category/nati ... lear-plantAmber G. wrote:Okay, how much power are we taking here? Care to give a number? (You may like to see Ramana's post long time ago)Also we are not talking of multi MW type power output.
If this is usual temp in spent fuel pool then heat extraction or power is not feasible, JMTNishiyama also said TEPCO sprayed some 195 tons of fresh water into a spent nuclear fuel pool at the No. 4 reactor’s building through the night, after finding from a sample taken Tuesday from the facility that the temperature of the water was 90 C, much higher than the usual 20-30 C
else 1-10 mw can be extracted and also depends on pool capacity+heat generation from spent fuel. This is only from Spent fuel pool.
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Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
Oh yes, I am for 100% newclear, but you didn't ask if it was fission, fusion or matter/anti-matter energy systems?Sanku wrote:Funnily enough, only ones making such remarks on behalf of others are nuclear at all costs NOW lobby.Mort Walker wrote:Amber G,
I can see it now. The EBs are going to scream about how unsafe the Arihant and the NERPA are and the massive radiation ecological disaster it will cause.
Please send Rakesh bhai's mithai to me. After all, its made with irradiated milk!
Non partisan folks see all sides of a issue.

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
From NISA report, full details of measurements.Amber G. wrote:For perspective (Total amount released rough values)
Chernobyl: 1800 PBq of I131 and 85 PBq of C137
Fukushima: 130 PBq (NISA) I131; 6.1 PBq (NISA) C137
http://www.nisa.meti.go.jp/english/file ... 0412-4.pdf

From IAEA
http://www.iaea.org/newscenter/news/tsu ... ate01.html
The Japanese Nuclear and Industrial Safety Agency (NISA) today issued a new provisional rating for the accident at the Fukushima Daiichi nuclear power plant on the IAEA International Nuclear and Radiological Event Scale (INES).
The nuclear accident at Fukushima Daiichi is now rated as a level 7 "Major Accident" on INES. Level 7 is the most serious level on INES and is used to describe an event comprised of "A major release of radioactive material with widespread health and environmental effects requiring implementation of planned and extended countermeasures". Japanese authorities notified the IAEA in advance of the public announcement and the formal submission of the new provisional rating.
The new provisional rating considers the accidents that occurred at Units 1, 2 and 3 as a single event on INES. Previously, separate INES Level 5 ratings had been applied for Units 1, 2 and 3. The provisional INES Level 3 rating assigned for Unit 4 still applies.
The re-evaluation of the Fukushima Daiichi provisional INES rating resulted from an estimate of the total amount of radioactivity released to the environment from the nuclear plant. NISA estimates that the amount of radioactive material released to the atmosphere is approximately 10% of the 1986 Chernobyl accident, which is the only other nuclear accident to have been rated a Level 7 event.
Earlier ratings of the nuclear accident at Fukushima Daiichi were assessed as follows:
On 18 March, Japanese authorities rated the core damage at the Fukushima Daiichi 1, 2 and 3 reactor Units caused by loss of all cooling function to have been at Level 5 on the INES scale. They further assessed that the loss of cooling and water supplying functions in the spent fuel pool of the Unit 4 reactor to have been rated at Level 3.
Japanese authorities may revise the INES rating at the Fukushima Daiichi nuclear power plant as further information becomes available.
INES is used to promptly and consistently communicate to the public the safety significance of events associated with sources of radiation. The scale runs from 0 (deviation) to 7 (major accident).
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
Edano aware in March that nuke crisis could be raised to worst level
TOKYO, April 13, Kyodo
TOKYO, April 13, Kyodo
Chief Cabinet Secretary Yukio Edano said Wednesday he was aware in late March of the possibility that the status of the ongoing nuclear crisis at the Fukushima Daiichi power plant could be raised to the worst level, but the decision did not come until later because of inconclusive data.
Japan's new assessment, raising the crisis to the highest level of 7 on an international scale, was announced Tuesday, about a month after a magnitude 9.0 earthquake and tsunami crippled the plant and caused radiation leaks, fueling widespread criticism that the government has acted belatedly.
The assessment now puts the situation at the Fukushima plant situation on a par with the 1986 Chernobyl catastrophe.
Edano told a news conference Wednesday that two government-related nuclear bodies said in late March that their crisis assessment estimates were based on radiation monitoring data from only three locations.
''The Nuclear and Industrial Safety Agency and the Nuclear Safety Commission of Japan said they could not vouch for the certainty of their estimates, so I told them to make a thorough, reliable analysis as soon as possible,'' said the top government spokesman, who added that he was informed Monday about the forthcoming change in assessment.
The government's nuclear agency on Tuesday upgraded its provisional evaluation based on an estimate that radioactive materials far exceeding the criteria for level 7 have so far been released into the external environment.
On the same day, Seiji Shiroya of the nuclear commission, a government panel, said in a news conference that he was aware as of March 23 that the crisis might be elevated to level 7, but left the decision to the agency because the assessment was the agency's responsibility.
On March 18, the agency provisionally set the level at 5, the same as the 1979 Three Mile Island accident in the United States.
Edano defended the way the government has handled the process leading up to Tuesday's announcement, saying, ''We have repeatedly issued instructions to relevant entities to fully disclose various information.''
He also said that Japan's safety standards will not immediately change as a result of the assessment upgrading because the level was based on additional analysis of existing data.
At the same time, the chief Cabinet secretary admitted that a proper assessment could have been possible more quickly if more extensive radiation monitoring data had been collected earlier.
''I believe we would have been able to make various decisions at an earlier stage if more monitoring of radioactive materials in the areas surrounding the plant had been conducted at more locations,'' Edano said.
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
Radioactive strontium detected outside 30km zone
Japan's science ministry says small amounts of radioactive strontium have been detected in soil and plants outside the 30-kilometer zone around the Fukushima plant where the government has advised people to stay indoors. Strontium could cause cancer.
The ministry has been monitoring the level of radioactive substances in soil and weeds in Fukushima Prefecture.
It found 3.3 to 32 becquerels of strontium 90 per kilogram of soil in samples taken from 3 locations in Namie Town and Iitate Village, 30 kilometers from the plant.
An extremely small amount of strontium was also found in plants taken from Motomiya City, Ono Town and Otama and Nishigo Villages. The areas are 40 to 80 kilometers from the Fukushima plant.
Strontium 90 has a half-life of 29 years. It tends to accumulate in bones and could cause cancer.
The ministry says the amount found is extremely low and will not have a negative health impact even if a person ingested one kilogram of the contaminated soil.
The samples were taken between March 16 and 19.
A nuclear engineering expert says the fact that strontium was detected proves that the fuel in the reactor or the spent fuel in the pool was damaged at that point. He says a hydrogen explosion occurred at Reactor 3 around that time and the particles may have been carried by winds.
Wednesday, April 13, 2011 07:52 +0900 (JST)
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
High radiation levels in sea off Fukushima coast
The science ministry says radiation levels in seawater off the coast of Fukushima Prefecture are the highest since it began monitoring them about 3 weeks ago.
The ministry says the level of iodine-131 was 88.5 becquerels per liter in a sample taken on Monday in the sea about 30 kilometers east of the Fukushima Daiichi nuclear plant. The figure is 2.2 times the government's upper limit for wastewater from nuclear facilities.
The level of cesium-137 was also the highest observed so far, but was below the limit.
Tokyo Electric Power Company says the iodine-131 level was 23 times the upper limit in a sample taken 15 kilometers from the plant.
This was the highest figure since TEPCO began taking samples 15 kilometers offshore on April 2nd.
Radiation levels are higher in the sea to the north of the crippled plant.
The government's Nuclear and Industrial Safety Agency says radioactive substances seem to be flowing and diffusing northward.
The agency says predicting the course of the flow is difficult and it will step up monitoring in locations where high radiation levels have been detected.
Wednesday, April 13, 2011 09:04 +0900 (JST)
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
"It's considerably different from Chernobyl," said Nishiyama
But Junichi Matsumoto, a spokesman for Tokyo Electric Power Co., was not so confident, saying he was concerned that the amount of radioactive materials may exceed Chernobyl in the end if Tepco fails to contain the ongoing crisis.
"Level 7 indicates a massive amount of radioactive leakage. We deeply apologize to residents around the plant and Fukushima Prefecture and society for causing concerns and troubles," he said.
Trade and industry minister Banri Kaieda, who oversees NISA, said most of the radioactive leakage has been due to the hydrogen explosions that occurred within the first few days after the twin natural disasters.
Kaieda said the government currently does not foresee any sharp spikes in radioactive discharge outside the plant compound for now.
"The most pressing issue at the moment is to prevent further (hydrogen) explosions from taking place and to curb the spread of radioactive materials . . . and currently, we do not expect to see a drastic increase in the mission," Kaieda said.
The estimates, however, only cover release by air, meaning the figure is likely to rise if leakage into the sea is included in the calculations. NISA said it will conduct a separate investigation on how much radioactive materials have been released into the Pacific Ocean.
Asked why NISA did not come forward with the data earlier if most of the release was made days after the disaster hit, Nishiyama said the agency wanted to gather a certain amount of data to make sure before making any assessment
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
^^^^
Interesting, do Chernobyl estimates include land and sea (no sea there right) leakages? Also how does one estimate land contamination?
Still the figures in this case are not really apple to apple comparison. Since not the total radiation discharge is taken into account. Otherwise the total discharge would quite likely be much higher (given that their chief way of removing radioactivity was to wash it with sea water and release the sea water)
Interesting, do Chernobyl estimates include land and sea (no sea there right) leakages? Also how does one estimate land contamination?
Still the figures in this case are not really apple to apple comparison. Since not the total radiation discharge is taken into account. Otherwise the total discharge would quite likely be much higher (given that their chief way of removing radioactivity was to wash it with sea water and release the sea water)
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
It seems that the Japanese cant do anything anymore without some one accusing them of acting for ulterior motives. Good lessons for quick reaction and transparency.
http://thestar.com.my/news/story.asp?fi ... rldupdates
Russia's nuclear chief says Japan exaggerating nuclear crisis
http://thestar.com.my/news/story.asp?fi ... rldupdates
Russia's nuclear chief says Japan exaggerating nuclear crisis
"It is hard for me to assess why the Japanese colleagues have taken this decision. I suspect, this is more of a financial issue, than a nuclear one," Sergei Kiriyenko said on the sidelines of a bilateral meeting between the Russian president and Indian prime minister ahead of a meeting of major developing economies.
.............
"I guess that maybe it could be linked to the definition of force-majeure with regard to insurance. I would pay attention to that. It is a bit strange," Kiriyenko said.
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
sankuji, i dont think you realise just how immensely ironic your statement is...
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Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
Lalmohan wrote:sankuji, i dont think you realise just how immensely ironic your statement is...


Lalmullah,
This sombre thread could do with a bit of humour. Anything to bring a smile.
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
From NISA report, full details of measurements.chaanakya wrote:Amber G. wrote:For perspective (Total amount released rough values)
Chernobyl: 1800 PBq of I131 and 85 PBq of C137
Fukushima: 130 PBq (NISA) I131; 6.1 PBq (NISA) C137
http://www.nisa.meti.go.jp/english/file ... 0412-4.pdf
http://img38.imageshack.us/img38/9936/fukd11.jpg
Thanks, this actually are exactly same figure which I gave.
What is more important, and obvious to any person interested in radiation measurement, will be, at Chernobyl there was also : 6500 PBq of Xe133, 27000 PBq of Np-239 and thousands and thousands Bq more, in a long list of other fission products....which are not there in Fukushima (or at a very low level) when all of this is taken into account, (Sorry, one would need more than plugging in Q=mcT /smile/) the total radiation comes out to be about 3-4% of Chernobyl.
Added later: Above is my estimate, you are free to make your own calculation..
Last edited by Amber G. on 13 Apr 2011 19:08, edited 1 time in total.
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
I dont?Lalmohan wrote:sankuji, i dont think you realise just how immensely ironic your statement is...

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
Lalmullah, I posted the link and the accompanying description did I not? Am I that poor in piskology?Lalmohan wrote:QED
You do me great dishonor.

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
If we can't extract power from the water in the spent fuel pond there could be one more use. It could be used for swimming pool since temp is normally 20-30 deg c only and there is almost negligible or low radioactivity. Faithful can swim and increase their longivity and also automatically get brain tumors removed besides partaking of goodness of radiation in equivalent doses of banana.
Unfaithful would be losing golden, or should I say banana, opportunity for long life and goodness.
Unfaithful would be losing golden, or should I say banana, opportunity for long life and goodness.
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
Lalmohanji:
^^^ One can't even make these things up..

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
Chaanakyaji (and others): Just curious, if you had watched Prof Muller's lectures (I gave the link before). It is for Freshman ( first physics course for college), and the very first lecture (Energy) does derive the internal energy of water.. (among many other energy related topics)..(No it is not q=mct /just joking/ ).
Watch the lectures (and may be do homework etc too) for radiation, nuclear energy etc too.
Prof Muller, if one does not know, is famous professor at UC Berkeley (his class has been called by many the 'best physics class in USA). Among other things he was inventor of most accurate method for radia-carbon dating etc.
If you follow the lectures, read the textbook, and do the homework, many fundamentals will be clearer. The course does not require advance math (may be just Calculus)
Watch the lectures (and may be do homework etc too) for radiation, nuclear energy etc too.
Prof Muller, if one does not know, is famous professor at UC Berkeley (his class has been called by many the 'best physics class in USA). Among other things he was inventor of most accurate method for radia-carbon dating etc.
If you follow the lectures, read the textbook, and do the homework, many fundamentals will be clearer. The course does not require advance math (may be just Calculus)
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
It may help, for those who are unfamiliar with Becquerel to have an idea on what it means in ordinary terms...Like knowing how much is a meter by comparing it with height of a small child)It found 3.3 to 32 becquerels of strontium 90 per kilogram of soil in samples taken from 3 locations in Namie Town and Iitate Village, 30 kilometers from the plant.
Becquerel just means 1 disintegration per second. so 32 Bq means there are 32 events (alpha particles, + beta particles + gamma photons) coming out every second.
For comparison
Your own body ( Mainly due to K40 ) is about 4000 Bq
A smoke alarm (which has Am-241 and found in almost every house) is about 35,000 Bq
Small Sr-90 sample which a typical physics student may see in a lab = 37,000 Bq (1 muCi)
Cosmic rays and background hitting your whole body = 20,000 Bq
A Banana (typical 150 gm) = 20 Bq
For cancer: Probability that a cell will get cancer due to one of these particles hitting a cell ..
about 1 in 30 quadrillion! (It also depends on the energy of the particle etc.. but this is order of magnitude calculation)
(If you consider human life span is about 3 billion seconds, you can estimate how much background radiation will do you harm and such things...)
(And NO this is not spin from pro/anti nulke guys.. it is simple scientific data point)
Last edited by Amber G. on 13 Apr 2011 21:20, edited 1 time in total.
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
amberG-ji, out of curiosity, what is the natural Bq level of ironic substances? and if possible, of Laconium?
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
^^^ given by (of course) = (m/m_a) (N_a) (ln 2 /Half_life).. we have to watch this thread to find the half life to get more accurate value. 

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
so far the half life seems to be very long
Re: 2011 Japanese Earthquake and Tsunami - News and Analysis
To add to my previous post, (before some one wants to "convert" Bq into mSV etc). It is not straight forward to convert this into how risky it will be for the body. (it is easy but you can not just substitute it in a formula like q=mcT) .
One generally uses a computer and model or empirical method (rather than theory). It depends on energy of the source, type of source, how far away is the subject (actually subject's various organs) (remember mSV is 'absorbed' dose), how much radiation is absorbed in skin or cloths ( all alpha rays are thus virtually harmless unless consumed) ...and if you eat .. how long the substance will remain in your body...etc...etc..
(For lot of materials, chemical toxicity is actually more of a concern than radioactivity)
One generally uses a computer and model or empirical method (rather than theory). It depends on energy of the source, type of source, how far away is the subject (actually subject's various organs) (remember mSV is 'absorbed' dose), how much radiation is absorbed in skin or cloths ( all alpha rays are thus virtually harmless unless consumed) ...and if you eat .. how long the substance will remain in your body...etc...etc..
(For lot of materials, chemical toxicity is actually more of a concern than radioactivity)