"We can’t see inside Fukushima Daiichi because all our robots keep dying"

[cdev]

Well, so much for the robot apocalypse. A few nukes will kill them just as much as us!

https://www.extremetech.com/extreme/245324-cant-see-inside-fukushima-daiichi-robots-keep-dying

https://www.extremetech.com/extreme/243904-fukushimas-reactor-2-far-radioactive-previously-realized-no-sign-containment-breach

https://en.wikipedia.org/wiki/Radiation_hardening

[Marco]

Time for tubes?

[Ian.M]

Last year's Fukushima robot thread for reference: https://www.eevblog.com/forum/chat/bad-news-for-bots-fukushima-cleanup-robots-overpowered-by-radiation-(videos)/

[brucehoult]

Things are certainly pretty grim inside Fukushima.

An interesting thing about that accident is that it's actually persuaded a number of people, including prominent greenies such as George Monbiot, that we should be using a lot more nuclear power. If Fukushima is the worst that can happen -- and it pretty much is .. no one uses designs like Chernobyl any more -- then nuclear is very safe indeed. No one who didn't work there has suffered at all from the accident. As opposed to the 15000+ people killed directly by the tsunami. Or about 10000 people killed every year world-wide in coal mining accidents.

[David Hess]

Time for tubes?

Time for pneumatic and hydraulic computing and fiber optic vision.

An interesting thing about that accident is that it's actually persuaded a number of people, including prominent greenies such as George Monbiot, that we should be using a lot more nuclear power. If Fukushima is the worst that can happen -- and it pretty much is .. no one uses designs like Chernobyl any more -- then nuclear is very safe indeed. No one who didn't work there has suffered at all from the accident. As opposed to the 15000+ people killed directly by the tsunami. Or about 10000 people killed every year world-wide in coal mining accidents.

And the people killed and displaced by dam failures.  Solar and wind power installation and maintenance is dangerous because of the heights involved.

[mtdoc]

One of the greatest shortcomings of humans is the inability (in general terms) to properly assess risk and danger beyond very short timeframes....

[Kleinstein]

The  Fukushima accident was bad, but still not worst case. The time between shutdown and the final failure of the reactor structure help to reduce the damage - so much the containment could capture most of the radioactivity. That delay also reduced the radiation right after the accident, so that workers could still go there to reinstall some cooling. There also was a lot of luck with favorable weather that send something like 95% of the radioactive emissions to the pacific. No such luck with a similar accident happening in France or Belgium.

The time right after the tsunami also showed one problem with nuclear power: they hesitated using see water for cooling (which might have stopped the worst, if done earlier) because this would have ruined the reactor and thus cause high costs. So there is always the balance between costs and safety - which is bad, as there are humans in charge with the inherent danger they bend the rules in favor of economics because they think the risks are not that large. This can happen at all levels - operators, company and government.

[cdev]

A group at NASA developed a vacuum based ceramic, glass and and metal "microtube" system for radiation hardened use a few years ago, which can be fabricated using fairly modern techniques.

This seems like a perfect application for it? It was particularly well suited for high radiation environments.

Maybe Japan is a case where "not invented here" groupthink syndrome is becoming problematic? 

[cdev]

Brucehouldt,

 the Chernobyl situation was (and remains) really bad. Its my understanding that radiation there is not diminishing. Its getting stronger.

They dont know why. Your assertion that radiation is cleaner, is - well, I don't agree with it in the slightest, I think its - uh- very shortsighted. I'll leave it at that.

I've discussed this with nuclear physicists, what they have told me doesn't leave me feeling reassured. I think that our current economic system is not evolved enough to treat issues of this kind as they need to be treated. With a higher level of responsibility. I think mtdoc nailed it there.

Also, the use of boiling water reactors and the production of hot nuclear waste which must be kept cool is extremely problematic.

Especially if we were to have a strong, 1859 level ("Carrington class" Solar storm) coronal mass ejection event which could destroy the transformers that hold together the power grid globally.

We would then have whats called the "loss of the ultimate heat sink" problem on a massive scale.

Lets not go there.

Pray!

[TheAmmoniacal]

Radiation phobia is very prevalent, even among intelligent and educated people. Sad - just no perspective.

[Cerebus]

I think that our current economic system is not evolved enough to treat issues of this kind as they need to be treated. With a higher level of responsibility. I think mtdoc nailed it there.

Economists call these 'externalities', costs of your actions that you do not bear. So if the fine for a radioactive release was greater than the costs of pumping sea water through the reactor to prevent it, then there is a 'rational' reason to take the economic hit of flooding the reactor with corrosive sea water. If, on the other hand, you can only see the cost of the reactor damage, the environmental costs become an SEP (Somebody Else's Problem). Externalities is why we need to have regulation, to ensure that people who make decisions take in the costs to others as well as the costs to themselves. When you have a system where maximizing profit is virtually legally mandated by most corporate law on the planet, you get the situation where common decency ("think of the effects on others") is overridden by the mandate to maximize profits.

[brucehoult]

I think that our current economic system is not evolved enough to treat issues of this kind as they need to be treated. With a higher level of responsibility. I think mtdoc nailed it there.

Economists call these 'externalities', costs of your actions that you do not bear. So if the fine for a radioactive release was greater than the costs of pumping sea water through the reactor to prevent it, then there is a 'rational' reason to take the economic hit of flooding the reactor with corrosive sea water. If, on the other hand, you can only see the cost of the reactor damage, the environmental costs become an SEP (Somebody Else's Problem). Externalities is why we need to have regulation, to ensure that people who make decisions take in the costs to others as well as the costs to themselves. When you have a system where maximizing profit is virtually legally mandated by most corporate law on the planet, you get the situation where common decency ("think of the effects on others") is overridden by the mandate to maximize profits.

The problem with your theory is that the places with the very worst pollution and environmental fuckups are exactly the ones where no one owns anything, there is no profit motive, and absolutely everything is run by professional bureaucrats.

I currently live in one of them, that got so fucked up between 1917 and 1991 that 25 years later it's not unfucked. (of course the same old Party people giving themselves all the factories etc didn't help). Central government manages to steal enough money from the provinces to make Moscow, St Petersburg, and Sochi bright and shiny (at least in parts), but the provinces are truly dire.

[Alex Eisenhut]

http://www.hts-homepage.de/Silizium/Silizium.html

And integrated tubes are called "thermionic integrated micro modules", and although I've never seen one, the references go back to the 1960s.

Then there's Nuvistors too.

I've seen it mentioned that tunnel diodes are "radiation resistant", but what that really means, I don't know. Magnetic core logic I suppose won't mind radiation.

Or maybe make a robot with cable operated mechanics, like a bicycle. Make it like a puppet, with a vacuum tube video system and hydraulic motors activated by the cables.

[Cerebus]

I think that our current economic system is not evolved enough to treat issues of this kind as they need to be treated. With a higher level of responsibility. I think mtdoc nailed it there.

Economists call these 'externalities', costs of your actions that you do not bear. So if the fine for a radioactive release was greater than the costs of pumping sea water through the reactor to prevent it, then there is a 'rational' reason to take the economic hit of flooding the reactor with corrosive sea water. If, on the other hand, you can only see the cost of the reactor damage, the environmental costs become an SEP (Somebody Else's Problem). Externalities is why we need to have regulation, to ensure that people who make decisions take in the costs to others as well as the costs to themselves. When you have a system where maximizing profit is virtually legally mandated by most corporate law on the planet, you get the situation where common decency ("think of the effects on others") is overridden by the mandate to maximize profits.

The problem with your theory is that the places with the very worst pollution and environmental fuckups are exactly the ones where no one owns anything, there is no profit motive, and absolutely everything is run by professional bureaucrats.

I currently live in one of them, that got so fucked up between 1917 and 1991 that 25 years later it's not unfucked. (of course the same old Party people giving themselves all the factories etc didn't help). Central government manages to steal enough money from the provinces to make Moscow, St Petersburg, and Sochi bright and shiny (at least in parts), but the provinces are truly dire.

Not my theory but pretty basic classic economic theory.

Externalities aren't about profits but costs, and your example doesn't demolish the theory but rather enforces it. What were the costs to those "professional bureaucrats" of behaving like they did/do? Nothing, so it was an externality, a "Somebody Else's Problem", so they could happily troll along buggering up everything for everybody but themselves. Just because externalities are easiest to spot in a Capitalist economy doesn't make Capitalism the exclusive venue for their effects.

[senso]

So, why dont they use a "local" hydraulic/air pump, and control from a remote site, long long fiber optics for vision, and they use either air or hydraulic lines to a control remote enought that you dont fry from radiation?

[donotdespisethesnake]

Nuclear power has been extensively tried and shown to be a complete and utter fucking disaster. There are plenty of safer and cheaper options, let's just move on from that failed technological panacea of the 1950s. Nuclear power based on Uranium was just a way to cash in from the arms race anyway, not because it ever made any sense.

About the only reason for nuclear power would be a crash program to mitigate global warming, but it's too late, we've fucked that up as well.

I suppose we may as screw things up thoroughly by spreading lethal radiation over the whole Earth, then get rid of humans altogether. Maybe in a few million years an intelligent species will evolve.

[cdev]

>Radiation phobia is very prevalent, even among intelligent and educated people. Sad - just no perspective.

The town of Fukushima is now totally abandoned "for some reason". So is the area around Chernobyl.

In order to prevent discussion of the underlying issues in  the media they put an unprecedented gag order on the Japanese media muzzling the press, on that issue, and then passed a national law vastly expanding press censorship.

When a government has so little confidence in the defensibility to a rational man or woman of their own positions that they must muzzle the press, or their people, that's not a government you should trust in any way.

There is an issue with extreme space weather and spent nuclear fuel (the "loss of the ultimate heat sink" problem) that makes me think we need a moratorium on further nuclear fission power plants.

We should concentrate on other means of power generation. The Sun is an excellent source of nuclear energy which we can use from a safe distance, naturally.

[brucehoult]

Nuclear power has been extensively tried and shown to be a complete and utter fucking disaster. There are plenty of safer and cheaper options, let's just move on from that failed technological panacea of the 1950s. Nuclear power based on Uranium was just a way to cash in from the arms race anyway, not because it ever made any sense.

That's really not the case. Nuclear is by far the safest way to generate electricity, and only hydro can come near to it for price, and only then if you have the luxury of suitable terrain and weather and low population density. Like New Zealand, for example. Or Canada (though they get 15% from nuclear).

France has, rather uncharacteristically, gotten on with it, iterated their designs to the point that they are very good and safe, and generate something like 75% of their electricity from nuclear. Most of the rest of Europe, and asia, generate 30% - 50% of their electricity from nuclear. France is also the world's largest exporter of electricity -- something that will only increase as long as they have to save the butts of neighbours who conduct energy policy for ideological reasons, not economic or safety ones.

[mtdoc]

Nuclear is by far the safest way to generate electricity,

That is simply an opinion - not supported by facts - and disputed by many well-informed nuclear engineers and scientists. Solar and wind are very safe - regardless of silly claims about workers falling off of wind towers

[Seekonk]

The  Fukushima accident never should have happened. The plant totally survived the tsunami.  That whole mess happened because TEPCO was cheap and wouldn't put the backup power in a safe location.  The first thing destroyed was the fuel tank for the backup generator so the generator sucked in sea water.  TEPCO management should be lined up and shot.  I worked at one of those plants.  All they talked about was how much something cost. It always comes down to people.  There have been at least 1,000 incidents with US nuclear weapons.  It is only a miracle that Georgia is still on the map.

[helius]

Solar and wind are very safe - regardless of silly claims about workers falling off of wind towers

That's a strawman argument: make it sound like falls are the only danger from wind towers, then call that "silly claims". There are many more dangers, the most common of which is blade failure. There have been over 100 fatalities from wind power from the 1970s to the present; this compares unfavorably to the fatalities from nuclear accidents over the same period.

[M4trix]

Radiation phobia is very prevalent, even among intelligent and educated people. Sad - just no perspective.

Something that you can't see, taste or smell and kills you in agony. I think those are good reasons to be afraid. 

[Kleinstein]

The price of nuclear power is rather difficult to quantify: much of the costs for decommissioning and waste storage have not jet occurred and are only first estimates. Also the price for building the plants are usually higher than originally planed.

Another problem is the costs for possible accidents or their insurance. There is essentially no insurance for nuclear power plants. The accidents in Fukushima, TMI and Chernobyl are abut what is expected from nominal MTBF, but the costs are hard to tell and can vary. Not that much statistics.

The last good cost estimates for nuclear power I saw where somewhere around 10 US-cents per kWh and thus not that low. Cost for essentially any power plant depends on the location, not just for nuclear.

Nuclear power also works best and thus lowest costs, when running 24/7 - so producing electricity even than when nobody needs it. On the other side wind and PV is not available all the time. So comparing electricity costs is not that easy - it is more than just one price per kWh. It depends one the local mixture how important these factors are.

[wraper]

The  Fukushima accident never should have happened. The plant totally survived the tsunami.

As well as Chernobyl. That thing had blown up only because they were conducting experiments at extreme conditions  . Should they not mess with it, nothing would happen till this day.

[mtdoc]

Solar and wind are very safe - regardless of silly claims about workers falling off of wind towers

That's a strawman argument: make it sound like falls are the only danger from wind towers, then call that "silly claims".

It's not a strawman, it's a direct response to an earlier post in this thread which made the claim that

Solar and wind power installation and maintenace are dangerous because of the heights involved .

There have been over 100 fatalities from wind power from the 1970s to the present; this compares unfavorably to the fatalities from nuclear accidents over the same period.

Surely you must realize there have been several hundred deaths directly and immediately attributable to nuclear power plant construction, maintenance and accidents during that time period. More importantly, the cancer deaths due to nuclear accidents, while impossible to quantify exactly, number in the thousands even by the most conservative estimates (in the hundreds of thousands according to some).

And how many deaths due to solar?

As i said, the statement made that "nuclear is by far the safest way to generate electricity" is not supported by the facts.

[TimFox]

There are several articles from the old days about Nuvistors in high-neutron flux areas.
For example (paysite):
http://ieeexplore.ieee.org/document/4323310/?reload=true

[wraper]

And how many deaths due to solar?

As solar panels first need to be produced, sure a lot of workers are exposed to dangerous environment. As well a lot of pollution do happen.
http://www.washingtonpost.com/wp-dyn/content/article/2008/03/08/AR2008030802595.html?referrer=emailarticle
http://www.businessinsider.com/solar-panel-makers-grappling-with-waste-2013-2

[mtdoc]

And how many deaths due to solar?

As solar panels first need to be produced, sure a lot of workers are exposed to dangerous environment. As well a lot of pollution do happen.

 Yes, absolutely!

But the discussion is about relative risks from different sources of electricity production.

The truth is that every electricity generating technology has associated risks, dangers and adverse environmental effects.

The enourmous amounts of concrete needed to build dams and nuclear power plants has risks and adverse effects assiociated with it as does mining of rare earths for solar and of course fuel for nuclear reactors. The transport and manufacturing of the materials needed to build hydro, wind, solar and nuclear generating facilities requires large amounts of fossil fuels and all its associated adverse effects.

There is no free lunch when it comes to electricity production. It all about the relative risks and adverse environmental effects.

[EEVblog]

That's really not the case. Nuclear is by far the safest way to generate electricity, and only hydro can come near to it for price, and only then if you have the luxury of suitable terrain and weather and low population density. Like New Zealand, for example. Or Canada (though they get 15% from nuclear).

France has, rather uncharacteristically, gotten on with it, iterated their designs to the point that they are very good and safe, and generate something like 75% of their electricity from nuclear. Most of the rest of Europe, and asia, generate 30% - 50% of their electricity from nuclear. France is also the world's largest exporter of electricity -- something that will only increase as long as they have to save the butts of neighbours who conduct energy policy for ideological reasons, not economic or safety ones.

And $25BN to stash the waste, not including the massive costs of decommission nuclear that no one ever wants to talk about because that's always a problem for the next political administration.
https://www.ft.com/content/db87c16c-4947-11e6-b387-64ab0a67014c
https://en.wikipedia.org/wiki/Nuclear_decommissioning

[EEVblog]

The last good cost estimates for nuclear power I saw where somewhere around 10 US-cents per kWh and thus not that low. Cost for essentially any power plant depends on the location, not just for nuclear.

And that consumer cost never includes the cost of decommissioning down the track and long term waste disposal.

[mtdoc]

The last good cost estimates for nuclear power I saw where somewhere around 10 US-cents per kWh and thus not that low. Cost for essentially any power plant depends on the location, not just for nuclear.

And that consumer cost never includes the cost of decommissioning down the track and long term waste disposal.

Yes, and of course the waste is not really disposed of. It is stored and managed, and will need to be for the foreseeable future. Unfortunately, currently that usually means storage in onsite "temporary" cooling ponds that depend on a fully functioning electrical grid.

[hammy]

"Tokyo Gov. Shintaro Ishihara said levels of radioactive iodine in tap water were more than twice what is considered safe for babies.
[...] Radiation from the Fukushima Dai-ichi nuclear plant has seeped into raw milk, seawater and 11 kinds of vegetables, including broccoli, cauliflower and turnips, from areas around the plant."

"Hundreds of thousands remained homeless, squeezed into temporary shelters without heat, warm food or medicine and no idea what to call home after the colossal wave swallowed up communities along the coast."

http://www.today.com/news/radiation-fears-spread-tokyo-drinking-water-2D80555569

[Someone]

And how many deaths due to solar?

As solar panels first need to be produced, sure a lot of workers are exposed to dangerous environment. As well a lot of pollution do happen.

 Yes, absolutely!

But the discussion is about relative risks from different sources of electricity production.

The truth is that every electricity generating technology has associated risks, dangers and adverse environmental effects.

The enourmous amounts of concrete needed to build dams and nuclear power plants has risks and adverse effects assiociated with it as does mining of rare earths for solar and of course fuel for nuclear reactors. The transport and manufacturing of the materials needed to build hydro, wind, solar and nuclear generating facilities requires large amounts of fossil fuels and all its associated adverse effects.

There is no free lunch when it comes to electricity production. It all about the relative risks and adverse environmental effects.

As discussed on a lengthy thread in the Renewable Energy sub forum, the estimates of power generation impacts are full of political and otherwise biased numbers:
https://www.eevblog.com/forum/renewable-energy/environmentalists-and-nuclear-energy/msg1088652/#msg1088652
It can be very hard to make a clean comparison between any different forms of generation as picking which events/characteristics/externalities to include or not can quickly throw the numbers in a particular direction.

[Someone]

"Tokyo Gov. Shintaro Ishihara said levels of radioactive iodine in tap water were more than twice what is considered safe for babies.
[...] Radiation from the Fukushima Dai-ichi nuclear plant has seeped into raw milk, seawater and 11 kinds of vegetables, including broccoli, cauliflower and turnips, from areas around the plant."

"Hundreds of thousands remained homeless, squeezed into temporary shelters without heat, warm food or medicine and no idea what to call home after the colossal wave swallowed up communities along the coast."

http://www.today.com/news/radiation-fears-spread-tokyo-drinking-water-2D80555569

Quoting a 6 year old news article is not bringing anything to the discussion here, especially one thats confounding the effects of the other natural disasters at the time. As of now the majority of the residents in the region are able to live on their previous sites and the clean up continues:
http://www.sciencemag.org/news/2016/03/five-years-after-meltdown-it-safe-live-near-fukushima
The end result will be a level of cleanup consistent with worlds best practice:
https://en.wikipedia.org/wiki/Fukushima_disaster_cleanup#Cleanup_of_neighboring_areas

[Someone]

It can be very hard to make a clean comparison between any different forms of generation as picking which events/characteristics/externalities to include or not can quickly throw the numbers in a particular direction.

There is no need to check numbers if people die.

How so? Every form of electricity generation (or other power generation..) creates deaths associated with it, its not unreasonable to want to use the safer methods available. The really murky statistics come in when you try and quantify lives "saved" by providing electricity (or cheaper electricity).

[yuzuha]

I'm thinking we should switch to molten salt Thorium based breeder reactors.   Produce very little waste and it is low level.   Also it is more efficient... no pressure vessel because it runs at atmospheric pressure, it will shut itself down if it overheats and does not need external power for safety systems.   Not only that, you can't make bomb plutonium with them either.   The US built several successful models but light water reactors were all the rage and they never put them into production, but I think India and France were thinking of researching production versions of these.   Orders of magnitude more thorium than uranium 235 anyway and it is generally a byproduct of monazite mining for rare earths such as niobium, samarium, neodymium and the like.

[Arjan Emm]

Decommissioning costs should really get included in the energy price. As of now decommissioning simply doesn't happen. We have shit loads of nuclear power plants built in the 70's that still run. They were designed for 20 years a live span, but they keep stretching that and now it's almost 50 years. Look thiange in belgium, they have cracks in the containment vessels and they repaired it?? You got to be kidding me. How do you do that when even a robot doesn't survive in there. They take what ever risk possible just to avoid decommissioning. It's just too expensive.

Fukushima is calculated to cost 240.000.000.000 dollar to clean up before they found out radiation inside is not 75 sievert but 500, so that number will go up. And nobody has a clue how to solve this problem.

And how do you do this, you stretch the rules. Personnel at the Fukushima can now work twice as long on site, how? Just double the daily radiation allowance.

[yuzuha]

Nuclear power has been extensively tried and shown to be a complete and utter fucking disaster. There are plenty of safer and cheaper options, let's just move on from that failed technological panacea of the 1950s. Nuclear power based on Uranium was just a way to cash in from the arms race anyway, not because it ever made any sense.

About the only reason for nuclear power would be a crash program to mitigate global warming, but it's too late, we've fucked that up as well.

I suppose we may as screw things up thoroughly by spreading lethal radiation over the whole Earth, then get rid of humans altogether. Maybe in a few million years an intelligent species will evolve.

I think that is mostly because they took nuclear submarine reactors and scaled them up to multi megawatt power plants then had to get out the bubblegum and bailing wire and tack on all these safety systems that are problematic in themselves!

[Alex Eisenhut]

There are several articles from the old days about Nuvistors in high-neutron flux areas.
For example (paysite):
http://ieeexplore.ieee.org/document/4323310/?reload=true

Wow, you really made this nerd happy! Off to the university and see if they can pull this up for me. Or the plain library, you never know.

Maybe a dusty old red light will go on somewhere that some lunatic is trying to build a nuclear ramjet...

[Arjan Emm]

It's been 6 years and with unlimited resources,  tepco and Toshiba are not able to make a robot to even make a proper picture of the inside of the reactor. Let alone clearing the site.
Humanity can't deal with the potential problems that can come from nuclear energy so we should stay away from it.

[Someone]

I'm thinking we should switch to molten salt Thorium based breeder reactors.   Produce very little waste and it is low level.   Also it is more efficient... no pressure vessel because it runs at atmospheric pressure, it will shut itself down if it overheats and does not need external power for safety systems.   Not only that, you can't make bomb plutonium with them either.   The US built several successful models but light water reactors were all the rage and they never put them into production, but I think India and France were thinking of researching production versions of these.   Orders of magnitude more thorium than uranium 235 anyway and it is generally a byproduct of monazite mining for rare earths such as niobium, samarium, neodymium and the like.

India is still pursuing a thorium fuel cycle as they have substantial reserves of it, but the wastes produced are still long lived radiation sources that are hard to handle just less of it.

[james_s]

Radiation phobia is very prevalent, even among intelligent and educated people. Sad - just no perspective.

Nothing gets people irrationally worked up like the word "radiation". I once had to explain to someone why they shouldn't be freaked out about the "Laser Radiation" warning sticker on the back of their CD player. Yeah, it's radiation, as in light, it radiates. That's not the same as ionizing radiation and that, while legitimately dangerous, also tends to create an irrational response. People worry about radiation from granite counters yet they sit out and deliberately bake in the sun, which emits plenty of ionizing radiation.

I'm not going to deny that nuclear power generation is potentially dangerous, but there is no known source of energy that does not have the potential to be dangerous or environmentally damaging. A large portion of the US gets power from burning coal and we *know* that belches toxic mercury into the atmosphere and that's not even mentioning the countless deaths and injuries from mining coal. Hydro is nice and clean but it interferes with salmon spawning and currently there was a recent near-disaster with ongoing efforts to repair damage to a dam. Wind power kills birds and who knows what other issues people have with it. Solar creates all kinds of nasty chemicals in the manufacturing process. I'm personally in favor of hydro, solar and wind power but I'm also cautiously in favor of nuclear power. The irony of the situation is that the anti-nuke lobby has kept a lot of Fukushima-era plants operating by preventing their replacement with modern much safer and more efficient plants that produce significantly less waste due to their greater efficiency. It's the cleanest method we currently have of producing the vast amounts of energy society consumes. Coal is one of the worst, natural gas is fairly clean but consumes a finite fossil fuel. Renewables are a great augmentation to primary sources but they're not going to meet our needs alone, at least not now.

[NiHaoMike]

Cats kill a few orders of magnitude more birds than wind turbines do.
http://www.treehugger.com/renewable-energy/north-america-wind-turbines-kill-around-300000-birds-annually-house-cats-around-3000000000.html
http://www.usatoday.com/story/money/business/2014/09/15/wind-turbines-kill-fewer-birds-than-cell-towers-cats/15683843/

I think the right direction to go is to make use of cheap technology in order to more effectively use alternative energy. The biggest energy users in a typical home - HVAC, hot water, and refrigeration - can use thermal storage that is far cheaper than batteries and lasts practically forever.

[Bud]

Do not know how many birds my cat kills but over a warm period of the year she gets about a hundred mice.

[brucehoult]

The last good cost estimates for nuclear power I saw where somewhere around 10 US-cents per kWh and thus not that low. Cost for essentially any power plant depends on the location, not just for nuclear.

And that consumer cost never includes the cost of decommissioning down the track and long term waste disposal.

Yes, and of course the waste is not really disposed of. It is stored and managed, and will need to be for the foreseeable future. Unfortunately, currently that usually means storage in onsite "temporary" cooling ponds that depend on a fully functioning electrical grid.

Something that never seems to be mentioned about nuclear waste .... but that should be understandable to anyone who can understand RC time constants ;-)

If a thing is radioactive for millions of years then it's not very radioactive.

If a thing is very radioactive, then it won't be for long.

[mtdoc]

Something that never seems to be mentioned about nuclear waste .... but that should be understandable to anyone who can understand RC time constants ;-)

If a thing is radioactive for millions of years then it's not very radioactive.

If a thing is very radioactive, then it won't be for long.

Imprecise terms like "very radioactive" or "not very radioactive" are not much help in any rational discussion of this issue.

If you're trying to say indirectly that the waste from nuclear power production and it's fission products is either not radioactive for long or not dangerous to humans, you're wrong on both counts.

The waste products from nuclear power production and their fission products have half lives ranging from hundreds to many thousands of years.  Most of them remain dangerous to humans for those timespans.

One thing that many engineers may not be aware of is that it is not necessarily "how radioactive' something is that determines its danger to humans.  It's degree of bioaccumulation and the rate of turnover that the tissues it accumulates in is often more determinant of its danger than "how radioactive" a substance is - however you want to quantify that.

[brucehoult]

Something that never seems to be mentioned about nuclear waste .... but that should be understandable to anyone who can understand RC time constants ;-)

If a thing is radioactive for millions of years then it's not very radioactive.

If a thing is very radioactive, then it won't be for long.

Imprecise terms like "very radioactive" or "not very radioactive" are not much help in any rational discussion of this issue.

If you're trying to say indirectly that the waste from nuclear power production and it's fission products is either not radioactive for long or not dangerous to humans, you're wrong on both counts.

The waste products from nuclear power production and their fission products have half lives ranging from hundreds to many thousands of years.  Most of them remain dangerous to humans for those timespans.

One thing that many engineers may not be aware of is that it is not necessarily "how radioactive' something is that determines its danger to humans.  It's degree of bioaccumulation and the rate of turnover that the tissues it accumulates in is often more determinant of its danger than "how radioactive" a substance is - however you want to quantify that.

I wasn't planning on eating it!

Some small amount is so hot it needs active cooling. But, necessarily, that's not for very long.

For the rest .. just preventing it from entering the general environment and keeping people 100m away from it is all that's necessary.

The world-wide annual production of high-level nuclear waste (that requires active cooling) is about a 20 metre cube. Medium level waste (that you just need to store and keep people away from) is about a 60 metre cube per year.

For comparison: a year's sales of iPhones in their retail boxes will fill a 50 metre cube.

[Carrington]

It is not directly related to Fukushima, but quite interesting too:
https://www.thesun.co.uk/news/2915352/russia-nuclear-bombs-arctic-radioactive-particles-europe/
https://europeannewsweekly.wordpress.com/2017/02/21/nunclear-hotseat-notes-for-22-feb-2017-iodine-131-in-europe-the-evidence/

[mtdoc]

I wasn't planning on eating it!

Bioaccumulation does not require that you eat the nuclear waste. 

The world-wide annual production of high-level nuclear waste (that requires active cooling) is about a 20 metre cube. Medium level waste (that you just need to store and keep people away from) is about a 60 metre cube per year.

For comparison: a year's sales of iPhones in their retail boxes will fill a 50 metre cube.

Not sure why you think that information is relevant.  This is an engineering forum and I'm sure most, if not all here recognize that the volume of a substance has very little bearing on it's danger or toxicity.....

[Ian.M]

Even if you need ten times more glass than the volume of high level waste, after glassification one deep mineshaft in dry stable continental crust could accommodate the world's high level waste for a century.  Plug with alternating layers of reinforced concrete and  tarred glasscloth for 100m then back-fill with bulk concrete.

The problem is NIMBYs, rabid greens, short-term politicians, and stock speculators that have made it difficult to do the sort of reprocessing required to safely run nuclear power plants long-term.  Most of the world's high level waste is building up in short term storage facilities because the greens don't want reprocessing and glassification plants sited in low population density areas, the NIMBYs + short term politicians make impractical in any democracy other than in a large government owned exclusion zone, the politicians are scared of being seen as promoting nuclear proliferation by increasing the supply of fissionables by reprocessing, and the stock speculators make it difficult to get the money to build the reprocessing and glassification plants.

[mtdoc]

The problem is that while in theory nuclear power should be able to provide a clean, safe, and cost effective electricity production, in the real world it fails on all counts.

One can argue night and day about what should happen with nuclear waste but real world experience has demonstrated that it cannot be dealt with in a safe, cost effective way.

Blame it on politicians, bureaucracy, "greens" (what ever that means..), NIMBYs or what have you.  The end result is the same: theory != practice.  It all comes down to human nature and the fact that we are not equipped as a species to safely handle something whose risks are not easily grasped and which span time frames longer than our evolutionary frame of reference for risk evaluation and avoidance.

[Paul Moir]

The  Fukushima accident never should have happened. The plant totally survived the tsunami.

As well as Chernobyl. That thing had blown up only because they were conducting experiments at extreme conditions  . Should they not mess with it, nothing would happen till this day.

Real life is always more complicated:  neither of these are the fault of simple causes.  Yes they botched the experiment, but there were other factors.  Also why they botched the experiment has interesting and important causes.  And why they had to conduct the experiment in the first place is an important cause.  You really need to dig into the roots.

Note that at Fukishima it wasn't just the generators that were susceptible, the electrical vaults for the reactors got flooded too.  So even when emergency power got there, there was nothing to connect it to. 

[helius]

Blame it on politicians, bureaucracy, "greens" (what ever that means..)

Like the politician who fired several rocket propelled grenades at a breeder reactor.

[Assafl]

Energy sucks. Humanity sucks energy like there is no tomorrow but energy sucks. Especially when there is lots of it.

When all is said and done - what you figure out is that energy is dangerous and therefore it is easy to rationalize a political bent as really bad science or extraordinarily well reasoned pseudo-science-ational-babble. Deaths / Per kWh generated justifies the viewpoint of this author and that all posters have. Now that we proved the point made above let's invest in this technology because it will make us great again and safer - and we can pull all the stops placed in front by the bleeding alt-right liberals.

Can one even grasp that what riled California was a freaking run-off for a dam? It is like destroying your house because the downspout clogged (or in this case - fell apart). Hydroelectric itself is not more dangerous then others. But the amount of energy in an artificial lake is freaking dangerous. Californians like the pollution aspects of hydro - but now ask: How long do dams last? One can drown in a bucket, a bathtub a pool, a lake or by a Tsunami, or the collapse of a dam (or its overflow).

Coal is very safe. It is safe because pollution is inherently safe-ly. One can freak out about one's cancer or other ailment - but it is hard to prove causality. Surely people die from lung cancer even in airy mountaintops? Would the deceased have been one of those - or would the bugger have died from heart problem 20 years later. Cancer can be the #1 or #2 killer so 0.5% of the earths population? Some would call that dangerous. Gas turbines are nicer than coal. And quite nice if you have gas reserves.... But even these are not 100% clean. So you are back to the coal issue - would the cancer have appeared on a mountaintop?

We should all live on mountaintops. Like lake Nyos. ooops... Looks like the alps but lake Nyos belched CO2 killing 1700 people "naturally". Was the CO2 certified organic? But one can live in Bhopal and die of MIC poisoning (500,000 people affected, 2-5K died). Man made so less "organic".

Solar and wind and the like - well - nice - but need energy storage. Energy stores (whatever technology) are dangerous. How do they die out? Do they fall over? Do they shed blades? And how many people do they kill per kWh they generate?

Some people prefer to co-opt nature into their decision: Like some still live near Vesuvius. There are streets where houses were built on top of Lava that last streamed in the 40's. Worse - Vesuvius is famous for its pyroclastic eruptions (the pictures of Vesuvius with the urban surroundings is just wrong - asking for trouble).

Pick your death. And when you calculate the risks (so as to con statistics and pick a less likely death) - please calculate it per kWh it produces (Yes - we all know the Casio solar calculator is moderately safe). Oh - and pick one where black swans can't happen.

[Vtile]

Well it is a bogus to say that the Nuclear power is somehow safe. It is far from it, it is the worst form of power considering the risks involved. Half of the Europe is still radiating (down fall by high altitude wind) from Chernobyl.  Even my hunting cabin 1600 km (1000miles) from Chernobyl have local hot-spot (long-range downfall scale). Bad thing about it that it accumulates to fish, mushroom, berries and a like. No other power source will share a such potential to turn whole continents to places that are unsuitable for living with one failure of technology.

Then there is the decomissioning, which share similar threads since the waste is highly toxic/radiating for next 10000..100000 years. We have had a periodic table about 150 years and english language less than 1500 years to put the time on perspective.

Chernobyl did couse direct or indirect death from tens to hundreds of thousands of people on former Soviet Union and Warsaw pack, but because of the nature of the USSR the then relevant downfall etc. figures were cleaned out (as were any other unpleasant fact). USSR did not even inform or admit the meltdown to the Europe, not until sensors on Stockholm Sweden (900 miles away from Chernobyl) did notice it. The hot cleaning were done by 200 000 soldiers, who weren't even properly informed where and what they were doing.  The radiation on ground were such strong on the cleaning site that the film did overexpose inside of the cameras. Still going on water contamination is unsolved.(A bit old news flash about it: http://www.independent.co.uk/news/chernobyl-leak-threatens-to-poison-ukraine-water-supply-1154021.html ) Mechanical (not soldiers) robots they then used on site were similarly failing as those are in Fukushima hot spots.


There is other hazards and we have been really good at poisoning our backyards for last 150 years or so, unfortunately many times with substances that are bioaccumulating and non biodegradable.

Now agriculture is also potential source of nuclear contamination, many phosphorous fertilisers have high amounts (in sense that it is put on our food sources) of nuclear material ( Uranium ). The total amount (metric tons) of uranium dispersed yearly to fields only in Germany were jaw dropping (no pun).


What comes to preventing human error and bad judgement on disaster preventing safety system, the floodgate control system of Port of Rotterdam is interesting concept (as there is no human involved on decision making).

We are living over of our resources that is the reason for many if not most of the problems we are facing globally.

[David Hess]

The last good cost estimates for nuclear power I saw where somewhere around 10 US-cents per kWh and thus not that low. Cost for essentially any power plant depends on the location, not just for nuclear.

And that consumer cost never includes the cost of decommissioning down the track and long term waste disposal.

That may be the case elsewhere but it is or was included for US nuclear plants.  Congress of course spent the money for other things.

https://en.wikipedia.org/wiki/Nuclear_Waste_Policy_Act#Payment_of_costs

[W2NAP]

Thorium video from periodic videos

but honestly at this point, every house and building should have solar panels on the roof generating electric. but we know the power companies would never want since they would go broke

[bji900]

So this appears to be a bashing of nuclear energy thread instead of talking about why the Robots are not working and solutions to solve them. Other than the occasional fiber optic vision or tube comment. I would actually find a discussion about how to solve the electronics problem very educational. I do not really understand the problems other than that radiation causes issues with modern semiconductors.

[grumpydoc]

but honestly at this point, every house and building should have solar panels on the roof generating electric. but we know the power companies would never want since they would go broke

Renewables might already have reached the point that it is inevitable.

http://www.economist.com/news/briefing/21717365-wind-and-solar-energy-are-disrupting-century-old-model-providing-electricity-what-will

As more people have local solar PV and the demand on the grid during sunshine hours drops then it becomes more and more expensive to maintain the backup thermal plants needed to fill the gaps. Increased costs are then going to push more people off the grid etc.

[Vtile]

So this appears to be a bashing of nuclear energy thread instead of talking about why the Robots are not working and solutions to solve them. Other than the occasional fiber optic vision or tube comment. I would actually find a discussion about how to solve the electronics problem very educational. I do not really understand the problems other than that radiation causes issues with modern semiconductors.

Radiation doesn't cause issues only for the modern semiconductor, but in general in all materials and technologies. Since it does have ability to interfere and change many atomic structures. It does also introduce noise to any circuitry, no matter the technology used. It also goes through lead (which formulaes have vanished from my head), the lead shielding only reduces the amount vs thickness, but not block all radiation out.

The subject is more of an nuclear physics than electronics

[james_s]

So this appears to be a bashing of nuclear energy thread instead of talking about why the Robots are not working and solutions to solve them. Other than the occasional fiber optic vision or tube comment. I would actually find a discussion about how to solve the electronics problem very educational. I do not really understand the problems other than that radiation causes issues with modern semiconductors.

What about having all the electronics external, controlling the robot via an umbilical cable? It's certainly possible to have an entirely vacuum tube based video camera. I wouldn't think electric motors and incandescent lights would be greatly affected by radiation.

[Vtile]

http://adsabs.harvard.edu/abs/2016SPIE.9969E..02M

[Ian.M]

So this appears to be a bashing of nuclear energy thread instead of talking about why the Robots are not working and solutions to solve them. Other than the occasional fiber optic vision or tube comment. I would actually find a discussion about how to solve the electronics problem very educational. I do not really understand the problems other than that radiation causes issues with modern semiconductors.

What about having all the electronics external, controlling the robot via an umbilical cable? It's certainly possible to have an entirely vacuum tube based video camera. I wouldn't think electric motors and incandescent lights would be greatly affected by radiation.

High voltage circuits at high radiation levels are problematic due to radiation damage to the insulators. e.g conventional Plumbicon camera tubes need around 700V for the electron gun.  High current electronics or very fine wire to get the magnetic fields to scan the beam are also problematic, and the close proximity to motors is likely to result in stray magnetic fields deflecting the beam causing picture distortion or even breakup.
 
Worst case: With modern MEMS techniques, producing a high speed high resolution mechanical scanner is practical.  One could use a Mihaly-Traub mechanical scanner in the camera, with front surface mirror optics instead of the front lens (as glass discolours when heavily irradiated), behind a thin fused quartz window to keep radioactive dust out with minimal light loss, and a lead labyrinth round the mirror folded optical path to keep radiation out of the colour splitting prism, final focus lenses, photocells and low voltage starved pentode video amps.  VGA resolution RGB + Sync would be practical.

Another option, although not as rad-hard would be the same thin window, front surface mirror optics and lead labyrinth round the mirror folded optical path, with a cassette of Silicon CCD sensor modules in a heavily shielded can.  Each time one dies, a solonoid is remotely pulsed to momentarily open the can and transfer a new CCD module to the camera focal plane.

[bji900]

So if lead reduces the effects of the radiation why can we not make a labyrinth of lead and a quartz window for the camera. I have seen documentaries of special nuclear reactor defueling machines that have concrete and lead labyrinths to keep this issue at bay. There would not really be that big of an issue with weight of your robot because we are not going to space and weight is not "really" a limiting factor. You may need a fairly beefy umbilical coated in lead shielding and on board power batteries for the robot. In my day dreaming of future projects would be a mining robot to use on mars for the Space X refueling system. This would face a similar radiation issue not as bad but still troublesome.

[Cerebus]

I wouldn't think electric motors and incandescent lights would be greatly affected by radiation.

Many materials that motors (and other modern mechanical devices) routinely make use of behave very differently in a high radiation environment. For example, many plastics such as polythene and nylon that are used for gaskets and bearings degrade rapidly with enough gamma bombardment (as in turn into heatshrink, or just crumble). It's one thing to design stuff to work in moderate radiation environments such as space, it's another thing to design things to work in radiation fluxes that are routinely used to deliberately change the fundamental properties of materials or transmute one element into another.

[Kleinstein]

I am also a little surprised to see the robots fail from the radiation: Most of the radiation should be beta or relatively low energy gammy. The beta radiation should not even get to the electronics. And lower energy gamma is reasonably easy (e.g. 10 cm of lead) to shield against. At least the older style power electronics part should be rather tolerant to radiation. Modern µC with fine structures might be rather sensitive, but this is something they should know about. I don't think they have to go back all the way to tubes or even pneumatics - dig out some old 6502 or similar. Not everything old is good though - some where quite sensitive to latch up, and even tubes can get upset by radiation. This is especially true if you go the very low currents for low power.

With the picture sensor you get some noise, maybe a lot, but this is something external (that is in an office, not at the robot) software should be able to clean up at the cost of a slow update rate. So no 30 fps - maybe only 3 , but who cares.   Maybe they could send in some of the planed mars rover designs. Still radiation hardening for space use can be different: AFAIK the difficult part in space are rare high energy particles (e.g. muons  or more exotic). This is different from a more uniform gamma background one expects in the reactor.

I don't see an urgent need to really send a robot to the extremely radioactive part at the reactor core. Waiting a little (e.g. 10 years) helps in having to deal with much lower radiation levels.
This also one reason why they still keep the high level nuclear waste in temporary storage. The level of heat release is in most cases still going down reasonably fast. So in 20-50 years they have less heat and can thus have easier disposal. However it is also true that they still don't have a final destination, because they postponed looking for one, since this might call for opposition.

[james_s]

I wouldn't think electric motors and incandescent lights would be greatly affected by radiation.

Many materials that motors (and other modern mechanical devices) routinely make use of behave very differently in a high radiation environment. For example, many plastics such as polythene and nylon that are used for gaskets and bearings degrade rapidly with enough gamma bombardment (as in turn into heatshrink, or just crumble). It's one thing to design stuff to work in moderate radiation environments such as space, it's another thing to design things to work in radiation fluxes that are routinely used to deliberately change the fundamental properties of materials or transmute one element into another.

That's interesting stuff. I find radiation fascinating if a little frightening. The strongest source of radiation I've ever had access to is a medical xray system and that's got to be orders of magnitude weaker than what you'd find in the reactor building. Even with those, the glass envelope of the xray tube does discolor over time from radiation exposure, I've never looked into the exact mechanism there.

[max_torque]

Let me put forward a Statement:

"Man is the most dangerous animal on this planet"

And the resulting hypothesis:

"Wholescale removal of man from our planet or large areas of it, is likely to prolong our planets existence"



Therefore i'm going to suggest that nuclear power is clearly the best option!


(I suspect in the long term, Nuclear is the best option simply because it has the highest energy density, and hence ROI, that we can leverage with our current knowledge and practical exploitation of physics.  Note is use the word 'i suspect', unlike some posters i'm not going to use the word fact, where it's quite clear that the incredible complexity and interlinking of the  system makes 'facts' almost impossibly difficult to validate.)

[Kleinstein]

One nasty effect of high levels of radiation is that it can cause oils used for lubrication to solidify by forming polymers. So a little like some oils getting sticky just from getting old, only induced by the radiation and thus possibly faster.
So even mechanical systems can be tricky if the radiation is very high. So it can be little things that can stop a robot.

The dark color at X-ray tubes can also be cause from the electron beam cracking oil or sputtering off some metal. The normally rather soft x-ray is not that likely to cause defects in the glass that turns it dark. However the higher energy radiation in the reactor might be able to do that.

[bji900]

Just imagine the test request for that robot. "Must survive melted down nuclear reactor levels of radiation for 7 days at 1m distance from the core" Test technician come back and says where am I supposed to find a place to test that..."Take it to Japan, they have the perfect place"...

[james_s]

Just imagine the test request for that robot. "Must survive melted down nuclear reactor levels of radiation for 7 days at 1m distance from the core" Test technician come back and says where am I supposed to find a place to test that..."Take it to Japan, they have the perfect place"...

Well they say there's a silver lining on every cloud. Certainly seems like taking any advantage we can of the disaster is a worthwhile thing to do. If it can provide a useful testing or research environment we may as well make use of it and hopefully gain some knowledge.

[Vtile]

One nasty effect of high levels of radiation is that it can cause oils used for lubrication to solidify by forming polymers. So a little like some oils getting sticky just from getting old, only induced by the radiation and thus possibly faster.
So even mechanical systems can be tricky if the radiation is very high. So it can be little things that can stop a robot.

The high amounts of radiation can (will?) change the properties of the steels also, so ie. the pressure vessels of the type VVER-440/213 need to be annealed in certain intervals to get rid of the enpridlement caused of "minor" design flaw.  VVER-440/213
Eastinghouse Reactor

[Assafl]

There may a much simpler engineering problem at work here.

Instead of Sieverts, the problem at stake may be in Yen. Tepco might just want more money.

The "robot dying" story is a cute way to get public empathy for taking a larger stake from the public coffer.

[Vtile]

I personally believe it is a legit problem. You can not easily find people to design a mobile robots which can survive in meltdown nuclear reactor.

Edit. A few obvious grammar cleanups.

[wraper]

There may a much simpler engineering problem at work here.

Instead of Sieverts, the problem at stake may be in Yen. Tepco might just want more money.

The "robot dying" story is a cute way to get public empathy for taking a larger stake from the public coffer.

Do you drink conspiracy kool-aid?

https://en.wikipedia.org/wiki/Radiation_hardening

[wraper]

Look at the noise on the video as radiation increases.

[wraper]

There a robot failures on the video, exposure for 10 minutes at shown radiation is enough to kill you in a week.

[mikeselectricstuff]

The dark color at X-ray tubes can also be cause from the electron beam cracking oil or sputtering off some metal. The normally rather soft x-ray is not that likely to cause defects in the glass that turns it dark. However the higher energy radiation in the reactor might be able to do that.

X-ray tubes typically start off dark brown - this is to make the glass very slightly conductive to avoid problems due to surface charges building up and messing with the electron optics.

[TimFox]

So if lead reduces the effects of the radiation why can we not make a labyrinth of lead and a quartz window for the camera. I have seen documentaries of special nuclear reactor defueling machines that have concrete and lead labyrinths to keep this issue at bay. There would not really be that big of an issue with weight of your robot because we are not going to space and weight is not "really" a limiting factor. You may need a fairly beefy umbilical coated in lead shielding and on board power batteries for the robot. In my day dreaming of future projects would be a mining robot to use on mars for the Space X refueling system. This would face a similar radiation issue not as bad but still troublesome.

Note that lead is an efficient shield for alpha, beta, and gamma radiation, but not for neutrons.  Concrete, water, polyethylene (especially borated), and other hydrogen-containing materials are good for neutrons.

[Assafl]

There may a much simpler engineering problem at work here.

Instead of Sieverts, the problem at stake may be in Yen. Tepco might just want more money.

The "robot dying" story is a cute way to get public empathy for taking a larger stake from the public coffer.

Do you drink conspiracy kool-aid?

https://en.wikipedia.org/wiki/Radiation_hardening

If by conspiracy you mean looking for funding - I guess I am. There is no shame (nor "conspiratorial" intent) - just that they'd need to buy more robots.

I am sorry if the original texts strike me as "wanting". For example, I am sure you are used to rads for measuring the exposure a chip has to radiation. But the radiation these poor robots get exposed is expressed in Sieverts. Sieverts are used for humans (damage to biological tissue). Perhaps androids too. But not robots. (Are the robots androids? If they are I am missing a vastly bigger picture here.)

It would be nice if they stated what parts failed, the radiation exposure dose that these parts that failed had, and what protection did they use (lead box, etc.).

As for money - if they need more robot parts - it will cost more money. And these are not cheap robot parts (using radiation hardened components).

If by conspiratorial - you mean however, believing that Obama would tap Trump? Nope.

[james_s]

The dark color at X-ray tubes can also be cause from the electron beam cracking oil or sputtering off some metal. The normally rather soft x-ray is not that likely to cause defects in the glass that turns it dark. However the higher energy radiation in the reactor might be able to do that.

X-ray tubes typically start off dark brown - this is to make the glass very slightly conductive to avoid problems due to surface charges building up and messing with the electron optics.

Hmm I have a couple that have a noticeably brown patch everywhere the glass is directly exposed to radiation, although I suppose it could be evaporated tungsten from the anode. Somebody told me once that it was caused by the radiation and I never bothered to question that.

[Vtile]

It would be nice if they stated what parts failed, the radiation exposure dose that these parts that failed had, and what protection did they use (lead box, etc.).

Indeed it would be nice to know what happened to those robots, but I wouldn't be too suprised if that knowledge is protected as a trade secrets. In that sense you are right, even disasters are a good business for some. That said, I haven't looked the subject and my tendency for pessimism cynicism might trick me here.

[wraper]

It would be nice if they stated what parts failed, the radiation exposure dose that these parts that failed had, and what protection did they use (lead box, etc.).

First of all, failed robots were abandoned. So there is no way to check what exactly has failed. And even if they were recovered, checking them is not a trivial task as they became radioactive as hell. You cannot just go and poke them because you won't live that long after that.

[wraper]

I am sure you are used to rads for measuring the exposure a chip has to radiation. But the radiation these poor robots get exposed is expressed in Sieverts. Sieverts are used for humans (damage to biological tissue). Perhaps androids too. But not robots. (Are the robots androids? If they are I am missing a vastly bigger picture here.)

Just LOL, do you think they are particularly concerned about the radiation robots are exposed at  ? Or, just maybe, about radiation which impacts humans?
EDIT, and BTW:

The rad is a deprecated unit of absorbed radiation dose, defined as 1 rad = 0.01 Gy = 0.01 J/kg.[1] It was originally defined in CGS units in 1953 as the dose causing 100 ergs of energy to be absorbed by one gram of matter. It has been replaced by the gray in SI but is still used in the United States, though "strongly discouraged" in the chapter 5.2 of style guide for U.S.

So yeah, US is special one, the same as with inches.

[Assafl]

Okay - I follow that the gray unit is better as an SI unit. my point was the use of Sieverts with a robot.

And my point about Androids was a slight referral to science fiction (like Phillip K. Dick). Obviously these are not androids. Just a camera mounted on a remote controlled robotic body.

[Assafl]

It would be nice if they stated what parts failed, the radiation exposure dose that these parts that failed had, and what protection did they use (lead box, etc.).

Indeed it would be nice to know what happened to those robots, but I wouldn't be too suprised if that knowledge is protected as a trade secrets. In that sense you are right, even disasters are a good business for some. That said, I haven't looked the subject and my tendency for pessimism cynicism might trick me here.

Good grief. Why cynicism???  Whenever there is something of this magnitude it is VERY hard to project just how much it will cost to handle it. Many times, when there is a flurry of non-scientific articles, and you look at the legislature (it would be the Diet in this case) - there may be discussions about further funding. Maybe Not.

Tokyo Electric cannot fund this - not entirely - it is vastly bigger dollars than what a utility is capable of handling. No cynicism. How much did Chernobyl cost? It doesn't become cheaper over time. Those idiots beaurocrats who let the people (and children) of Pripyat stay in place. How much did it cost to do the surgeries to get the 5000 or so thyroids out. And the medication for life.  Who do you think pays for this shit??? Not reactor unit 4. For sure.

[raspberrypi]

Radiation phobia is very prevalent, even among intelligent and educated people. Sad - just no perspective.

Nuclear power is our only out to the global warming epidemic right now. Nuclear can b safe just dont use water as a moderator or coolant. The only reason why we dont have NaK cooled or pebble reactors is because nixon favored the water cooled designs and not enough money was put into them. Coal power plants actually emit more radiation around the plant then nuclear ones. We worry about the waste as a 1000 year problem but we are now using the what was considered waste 50 years ago as fuel. Who knows what solutions we will come up with in the next 50 years. Even water cooled reactors are safe as long as they have reliable power source to cool long enough for a safe shut down.

[D_Money22]

I would actually follow up on that by taking it one step further, the current pressurized reactor designs are awful. Not only are they inefficient, when something goes wrong (as we have seen) your strating internal pressure is well over 100 atmospheres, plus any additional generated by the catastrophic failure of the reactor and uncontrolled fissioning and decay. I firmly believe nuclear is our best option (at least short term, with a case for long term) for combating climate change. However, I think a whole lot more thought needs to be put into designs including molten salt reactors, such as thorium reactors, as these designs hold incredible potential to solve many of the problems I previously identified.

[Assafl]

I would actually follow up on that by taking it one step further, the current pressurized reactor designs are awful. Not only are they inefficient, when something goes wrong (as we have seen) your strating internal pressure is well over 100 atmospheres, plus any additional generated by the catastrophic failure of the reactor and uncontrolled fissioning and decay. I firmly believe nuclear is our best option (at least short term, with a case for long term) for combating climate change. However, I think a whole lot more thought needs to be put into designs including molten salt reactors, such as thorium reactors, as these designs hold incredible potential to solve many of the problems I previously identified.

The concept of "putting more thought" doesn't really work in safety engineering. Sure - you put all the smarts together and figure out all the possible scenarios. But then come a black swan and whatever you prepared for is insufficient (inexperienced operator & crappy experiment; tsunami; earthquake; too much rain in a particular place in California; a hurricane; a faulty seal from Martin Marietta; or even a radioactive Russian satellite that falls on Canada). Sure - there were many ways that the Fukushima accident could have been averted. But just "putting it higher" - has its own drawbacks. Longer cables, perhaps more sensitivity to earthquakes etc.

I am pro nuclear but am severely jaded (my father has a PhD in nuclear safety engineering - so obviously my entire family thinks nuclear is a sound way forward with rising energy demands). But going headstrong into the causes and effects of these disasters is the only way to assuage concerns regarding safety. Just like the flight industry reacts quickly and resolutely to flight disasters (and near accidents) - correcting systems and procedures that result in safety risks.

Perception is a problem. Lead poisoning is scary - but it was not when the big oil companies stood against unleaded fuels. Chemical pollution is also horrible - yet people are fine with having a stack near their house. But genetically modified foods - or radiation? Many go gaga. But then again, I am sure there are Italians living on the slopes of mount Vesuvius who are terrified of pressure cookers. Go figure..   

[wraper]

Okay - I follow that the gray unit is better as an SI unit. my point was the use of Sieverts with a robot.

So should they sent some human there to measure in Sieverts?

[Assafl]

Should they send humans in there? No. At least I wouldn't go in there.

But this thread (and the articles discussed) are not about the risk of radiation to humans. It is about the risk of radiation to robots. I cannot think of an equivalency of dose applicable to flesh and organs applying to a radiation hardened CPU. That is usually in rad or as you pointed out gray.

I would have preferred that the article would be more scientific. Stuff that starts with "1 is a lot - it is what NASA allows astronauts over their entire life" and then goes to show the robots die as well - what is it really about? Why are they posting this? Is it funding? Is it blaming Toshiba for bad engineering? Is it to scare people that large doses of radiation is bad? Duh.

So radiation kills electronics. Wow. Maybe it is news to you. Good. Maybe that is why the high powered RTG are always spaced many feet from the electronics they power - from satellites to moon surface devices. Except in pacemakers. But those are actually pretty low power.

[wraper]

So radiation kills electronics. Wow. Maybe it is news to you. Good.

During conversation it sounded like it was news to you. It was you that claimed that robots fail not due to radiation but conspiracy:

Instead of Sieverts, the problem at stake may be in Yen. Tepco might just want more money.

Should they send humans in there? No. At least I wouldn't go in there.

But this thread (and the articles discussed) are not about the risk of radiation to humans.

C'mon, do Tepco or whoever care about this tread and what we are discussing to start measuring in different units? Did they send those robots for the sake to test their rad hardness? Or to estimate danger for humans, as I say it again.

[Seekonk]

If we just sterilized a lot of people, world problems would go away.  What happened to ZPG.

[cdev]

The biggest problem with fission reactors is the spent fuel remains "hot" and problematic for thousands of years, presenting a huge storage problem which the owners of these plants often attempt to make society eat the cost of. It has to be cooled, continuously cooled by one means or another. That's why I think we should not build any more nuclear fission reactors until we've got a more responsible world with better technology to safely dispose of the nuclear waste. Corporations are often completely irresponsible and incapable of managing such materials safely long term.

Right now these spent fuel ponds all around the world are each a disaster waiting to happen.

[SeanB]

Spent fuel is not really a problem. Remember that all the uranoim mined in the world is basically a recovered material from natural reactors, that operated for millenia, were in water soaked silts and muds, and where the remains are still contained there 450 million years later.

The deposits were made by erosion of volcanic rock which has Uranium group metals in it that were oxidised by the atmosphere as the rock eroded, and were washed down rivers to be separated naturally by mass into pockets of heavy minerals, and which were in turn covered with mud and silt till there was enough for a water moderated natural reactor ( higher concentration of heavy nucleotides then to start the reaction going) to start up and run for long enough to boil off the water, cool down and get wet again and repeat the cycle. This went on for a long time till the most active materials were exhausted, and the by products stayed in the same locations for the 450 million years, sitting in sandstone with water flowing through, till they were mined for the current power plant uses.

So choose, low level waste mildly radioactive for long periods, like living in Edinburgh on top of a massive block of radioactive basalt and granite, exactly like people love as a kitchen cutting surface and as a counter top all round the room, with some high level waste that will decay in a century to pretty much the same. Or live with a coal plant putting 100 times as much out into the air you breath, or a gas powered plant doing the same with Radon gas, or with solar panels made with toxic elements in them.

The reactors were in Gabon, at a little place called Oklo, and are a source of a lot of materials along with uranium.

[mtdoc]

As cdev points out spent nuclear fuel remains a problem for thousands of years. And no it is not analagous to low level naturally occurring radiation:

Spent nuclear fuel is highly radioactive and potentially very harmful. Standing near unshielded spent fuel could be fatal due to the high radiation levels. Ten years after removal of spent fuel from a reactor, the radiation dose 1 meter away from a typical spent fuel assembly exceeds 20,000 rems per hour. A dose of 5,000 rems would be expected to cause immediate incapacitation and death within one week.
Some of the radioactive elements in spent fuel have short half-lives (for example, iodine-131 has an 8-day half-life) and therefore their radioactivity decreases rapidly. However, many of the radioactive elements in spent fuel have long half-lives. For example, plutonium-239 has a half-life of 24,000 years, and plutonium-240 has a half-life of 6,800 years. Because it contains these long half-lived radioactive elements, spent fuel must be isolated and controlled for thousands of years. A second hazard of spent fuel, in addition to high radiation levels, is the extremely remote possibility of an accidental “criticality,” or self-sustained fissioning and splitting of the atoms of uranium and plutonium.

In addition - spent fuel rods initially require active cooling for several years or risk igniting of the zirconium cladding which could result in massive atmospheric spread of dangerous radiation. One major, extended, and widespread electrical grid outage and that danger becomes real.

In general humans just cannot adequately deal with risks on a very long time frame.  We have a hard time comprehending risks beyond the short term - our brains are not wired for it. Immediate dangers activate our limbic system and motivate us to act quickly. Medium term dangers (up to a few years out) can motivate us adequately (via the neocortex) - since our evolutionary history included events which left those who did not react to such potential threats (decline of local food resources, etc) behind.

But we just cannot as a species deal with such long term risks - risks that extend far beyond the length of even the most long lasting of past human civilizations.

I think the fact that otherwise well informed, technically savvy members of this forum can say things like "spent fuel is not really a problem" demonstrates that.

[james_s]

It has always seemed to me that if the spent fuel is that active still, there ought to be much more energy that can be extracted from it. Surely if it has to be actively cooled we can use that thermal energy for something useful?

[SeanB]

Exactly, but there is no political will to reprocess that to blend with virgin fuel and use it again, so it sits there boiling water in a pond for decades, instead of making useful steam to generate power.

[james_s]

Exactly, but there is no political will to reprocess that to blend with virgin fuel and use it again, so it sits there boiling water in a pond for decades, instead of making useful steam to generate power.

A lump of it in a lead vault in my back yard could heat my house for free for the rest of my life. Obvious logistical problems there, but I'm sure there are larger scale operations where something like that could make sense.

[BrianHG]

Cant wait for cheap fusion power, though once we have it, I'm sure there will be reasons it wont be cheap for the regular end consumers...

[james_s]

Depends on one's definition of cheap. My electricity is about 8.2c/kWh, IMO that's pretty cheap. Even if the energy source was free, there are still a lot of costs in building and maintaining the infrastructure. I'd be willing to pay more than I do already if it meant clean, environmentally safe power in quantities that could meet our demand and save fossil fuels for applications in which they are not so easily replaced. I don't think we're going to see electric jumbo jets any time soon. Even if you could make a battery that matched the energy density of kerosene, it's not going to get significantly lighter as the energy is consumed as occurs with liquid fuel.

[Alex Eisenhut]

Cant wait for cheap fusion power, though once we have it, I'm sure there will be reasons it wont be cheap for the regular end consumers...

Sure, we just need to exceed the conditions at the heart of a star by a few orders of magnitude and solve the vexing problems of neutron activation of the (non existent as yet) blanket material/structures to actually extract heat from the reaction. Because unlike Star Trek, fusion reactors will just be glorified steam turbines.

http://physics.ucsd.edu/do-the-math/2012/01/nuclear-fusion/

...but

www.generalfusion.com

Let's just say I'm not packing for my warp drive tour of the galaxy just yet.

[Assafl]

But we just cannot as a species deal with such long term risks - risks that extend far beyond the length of even the most long lasting of past human civilizations.

I think the fact that otherwise well informed, technically savvy members of this forum can say things like "spent fuel is not really a problem" demonstrates that.

I don't think that technical minded people who say "spent fuel is not really a problem" are asking to ignore long term risks. I think what they are reflecting on is that storing lots of potential energy - in whatever form it happens to be in - can be a poison pill.

First: lets get NIMBY out of the way - if a dam in California breaks - it is their problem. And sure, coal emissions only heat up the other side of the world and cause cancer to "those" people. And many agree fossil fuels seem limitless. But that is turning a blind eye - the risks and grave dangers inherent by ANY storage of potential energy are only ignored by the same types who live on the slopes of Mount Vesuvius and are afraid of pressure cookers. It is "those" people.

Get over it - potential energy is generally safe if it is 12V on a 100uF capacitor - Anything over that is asking for trouble and utterly dangerous.

And YES: Radiation is scary; Global warming is scary; Lead pollution is scary (any pollution is scary); Dams collapsing is scary; Flying turbine blades are scary (even if they are very high up and very big). Heck - even a hand-granade is scary (and that is some cockamamie potential energy in the form of piddling chemistry - not enough to kill a fly a 100 yards away...); I even get scared standing on the ledge of a cliff - potential energy is (and should be) scary.

The only thing substantially scarier than storing potential energy is NOT having it when we need it.

[wraper]

It has always seemed to me that if the spent fuel is that active still, there ought to be much more energy that can be extracted from it. Surely if it has to be actively cooled we can use that thermal energy for something useful?

That is unfeasible. It's much more effective to supply heat from nuclear power station, and this actually do happen, I've seen myself hot water pipes going from nuclear power plant to the nearby town. https://www.iaea.org/NuclearPower/NEA_Cogeneration/index.html