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Fukushima

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Re: Fukushima

#151

Post by 542458 »

e12e wrote: post #140
dfox wrote: post #117

Earlier quoted context omitted.

The limit is 50mSv per year, not per hour. Sievert is cumulative unit that has to be either qualified by time or measured over entire lifespan to be meaningfully comparable. But on the other hand quantitatively measuring and comparing radiation effects is hard problem as there is essentially nothing that can be precisely measured and at the same time has any meaning as to biological effects, in practice the conversio…

Would appear that the limit is similar - the "red zone" is for "(> 50 mSv/y)" (note "more than") -- and the sign at the end "Leaving the zone" reads 4.9 mSV/h. That'd be about 42.000 mSV/year -- if we assume constant dose. Or put it another way -- stay an hour and you're at the (safe) limit of exposure for a year. As for all the comments on how nuclear isn't all that dangerous -- how much do we really know about peop…

It's actually not clear how low doses of radiation over a long period of time affect human health. Estimates and standards are usually built assuming that a short, intense dose and a long, slow dose are the same as long as they contain the same quantity of radiation (the Linear no-threshold model). However, there is doubt about how valid this is for long-term doses.

There are a few places on earth that have naturally high radiation levels (up to 250mSv/year), including many places with large granite deposits or hot springs. However, these places often do not show any higher cancer incidence (or other relevant health problems) than other areas, possibly suggesting some sort of limit before radiation becomes harmful (the Threshold model).

Some studies actually show significantly lower cancer incidence than other areas. This has prompted the idea of Radiation hormesis, that low doses above background have some benefit. We do know that low doses do stimulate cell repair mechanisms in different ways than large doses do, so it does seem possible (although real-world data is mixed). The effects are not well understood at present, and it's an area that is under ongoing study. Unfortunately, it's an absolute devil to research!

Re: Fukushima

#152

Post by ifdefdebug »

kenesom1 wrote: post #54

The worst case scenario for a nuclear plant accident is millions of casualties and the long-term contamination of major population centers. 152 of the world's 211 nuclear power plants have more than 1 million people residing within 75 km. A plant in India has 16 million living within that radius. Fallout could be dispersed over an area thousands of miles wide. The worst case scenario for an accident at a solar power…

Just up voted this to balance down votes. It's a shame to down vote something just because you dislike an opinion.

Re: Fukushima

#153

Post by fixermark »

inatreecrown wrote: post #35
ggreer wrote: post #17

I found the pictures fascinating, but the accompanying text marred my enjoyment. Considering the circumstances of the Fukushima disaster, the anti-nuclear sentiment really irked me. The Tōhoku earthquake & tsunami killed close to 20,000 people. The author completely ignored those victims. Instead, he focused on Fukushima, which will cause around 150 deaths from cancers. For every tragedy created by Fukushima, there a…

Get the facts straight: Fukushima is human failure. In the accident the neccecary cooling could not be supplied. As a result, people will die of cancer from the radiation. The tsunami is not human failure, and to say that living by the sea is human failure is another discussion completely.

There are two fallacies people are often susceptible to:

1) They don't factor in the value of "background" material and over-emphasize the foreground.

2) They feel that in a "natural" state, they are in control of their fate (Azimov had much to say on this one, and the ending of "I, Robot" is quite illuminating).

Fukushima did not go as well as it hypothetically could. And yes, the nuclear contamination is a disaster.

But let's look at what happened because Fukushima was there:

- electricity was supplied to drive the devices that informed the public about the earthquake risk and how to escape it.

- electricity was generated (prior to the loss of the plant's capacity) that drove the infrastructure that people relied upon to escape the tsunami wave

I think that the question of how the Fukushima prefecture would have fared sans plant is a reasonable question. Because the absence of the dangerous technologies we rely upon is not a state of safety; it's a state of nature, and we build devices to escape the pure state of nature because we know by experience it's inherently somewhat hostile to human life.

Future plants on coastlines should be built with the lessons learned from Fukushima's failure-mode in mind. Saying Fukushima itself was a failure is actually a larger step than it appears. How many lives were saved prior to and leading up to the tsunami by the power the plant generated?

Re: Fukushima

#154

Post by 13thLetter »

jessaustin wrote: post #149
tptacek wrote: post #114

Earlier quoted context omitted.

It's impolite to accuse people on an HN thread of being deceptive. It also doesn't add anything to thread itself, so why bother?

[EDIT] Nuclear power supporters believe themselves correct, so pointing out the spin isn't an accusation of deception per se . [EDIT] They're not trying to fool us, just to advocate their position. It is still useful for undecided parties to notice the spin and take it into account. EDIT: Admittedly, "trying to blind people" is not a charitable characterization.

"True believers" and "rose-tinted vision" and "spin" aren't particularly charitable phrases, either. You should engage with the opposing side's arguments instead.

Re: Fukushima

#155

Post by 13thLetter »

ArtDev wrote: post #135
Trombone12 wrote: post #45

Earlier quoted context omitted.

Coal is the most common in the US and honestly you should have stopped relying on it several decades ago. But of course, you got the nukes so you needn't bother with paying for your share of the climate change damages.

In the Northwestern US we get most of our power from hydropower and wind. Coal has a massive human cost in human health that makes it absurdly expensive overall. Personally, I would like to see and end to coal and nuclear power.

Why would you like to see an end to nuclear power?

Re: Fukushima

#156

Post by ifdefdebug »

ggreer wrote: post #17

I found the pictures fascinating, but the accompanying text marred my enjoyment. Considering the circumstances of the Fukushima disaster, the anti-nuclear sentiment really irked me. The Tōhoku earthquake & tsunami killed close to 20,000 people. The author completely ignored those victims. Instead, he focused on Fukushima, which will cause around 150 deaths from cancers. For every tragedy created by Fukushima, there a…

People overcame the tragedies created by the earthquake disaster. They grieved their dead and rebuilt their towns. Now life is going on - outside the Fukushima area.

The Fukushima disaster is not going away anytime soon. About 100,000 people lost everything, no rebuilding in sight. Former house owners are still living in containers.

Radioactive water is entering the environment since then. In 30 years, maybe someone will compare cancer statistics in that geographic area before and after the disaster. I doubt that figure of 150 deaths will hold then.

So it's perfectly normal to cover the Fukushima event as an ongoing disaster today. The earthquake and the tsunami are history. Nothing absurd about that.

Re: Fukushima

#157

Post by jessaustin »

13thLetter wrote: post #154
jessaustin wrote: post #149

Earlier quoted context omitted.

[EDIT] Nuclear power supporters believe themselves correct, so pointing out the spin isn't an accusation of deception per se . [EDIT] They're not trying to fool us, just to advocate their position. It is still useful for undecided parties to notice the spin and take it into account. EDIT: Admittedly, "trying to blind people" is not a charitable characterization.

"True believers" and "rose-tinted vision" and "spin" aren't particularly charitable phrases, either. You should engage with the opposing side's arguments instead.

Experience has taught that on the topic of nuclear power, HN is the wrong forum for that, for me. I tend to get wound up. 13years' original observation that radiation release should be compared on overall rather than "nominal" performance hasn't been contradicted in this thread, and my response to that is agreement. Others may prefer to discuss tone and comportment.

I hesitate to add anything else, but the following proposition doesn't seem to generate much discussion so perhaps it's safe. Consider the fact that regular power plants are regularly built by mostly private investment, while nuclear power plants are only built by the state. This suggests that nuclear power is not profitable in a strictly economic sense.

Re: Fukushima

#158

Post by zurn »

mikekchar wrote: post #128
Kankuro wrote: post #120

Earlier quoted context omitted.

I guess he was talking about higher walls around the (few) nuclear plants, not the whole country. That would not make the country "a jail where the only place I can see the ocean is from on top of a mountain".

The water will just go around the wall. I think people don't quite understand the logistics involved. You have this massive wave travelling at 300 km/h. The seawall will break up the wave, but you have to have it long enough to prevent the water from reaching the bits that you want to protect before it retreats (often 20-30 minutes later). Do a google search for "tetrapod japan images" to see what the beaches around…

But you could easily build the plant on naturally or artificially higher ground.

Re: Fukushima

#159

Post by throwawayaway »

notahacker wrote: post #90
brc wrote: post #49

Earlier quoted context omitted.

And that's before you compare death/injury per Mw produced. On that measure Solar power is more dangerous than nuclear given how many people die falling off roofs while installing or maintaining solar panels.

I'm assuming this stat stems from the famous blog article which rejected even the most conservative and widely-accepted Chernobyl death estimates and then calculated solar deaths based on the (unsupported) assumption that 1 in 6 roofing casualties were the result of installing solar panels...

> http://nextbigfuture.com/2008/03/deaths-per-twh-for-all-ener...

"The World Health Organization study in 2005 indicated that 50 people died to that point as a direct result of Chernobyl. 4000 people may eventually die earlier as a result of Chernobyl, but those deaths would be more than 20 years after the fact and the cause and effect becomes more tenuous."

So he uses 50 deaths for his calculations.

"1/6th of the 9 million roofing job accidents would be about 50 deaths from installing 1.5 million roofs if other countries had similar to US safety. The amount of roof installations is increasing as a percentage. 4 TWh from roofs PV. So 12.5 deaths per TWh from solar roof installations. Assuming 15 years as the average functional life or time until major maintenance or upgrade is required. The average yearly deaths from rooftop solar is 0.83/TWh."

How did I miss that! Incredible.

Re: Fukushima

#160

Post by zurn »

mackwic wrote: post #53
simoncion wrote: post #24

Earlier quoted context omitted.

While it is true that coal is not the only non-nuclear power generation mechanism, it is -by far- the most common in the US. It is also true that > When you hit a nuclear plant with the fifth largest earthquake ever recorded, then immediately follow that with a twenty foot high tsunami, and then it explodes, it still kills fewer people than an average coal plant does every single year when everything goes perfectly.…

I suggest you to learn a bit about power grid engineering. Basically, the fact that we can't store electricity means that when you power on your toaster, somewhere a power plant has to increase its power to compensate. But the nuclear power plant takes up to 2 days to startup. It's not sustainable for the daily life where consumption change every hour. That's why there is the need for more agile power plant, where fu…

Nuclear can do load following pretty well (as does coal) as long as there plant supports it - reasonably recent ones are required to by regulations. It is used in that mode commonly eg in France and Germany. The economics are another thing of course, you don't save much in operating costs by throttling output.

Stopping to 0% is not needed in normal load variation, thanks to toaster usage patterns.

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