Author Topic: "We can’t see inside Fukushima Daiichi because all our robots keep dying"  (Read 18842 times)

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Offline mtdoc

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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.
 

Offline Paul Moir

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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  :palm:. 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. 
 

Offline helius

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Offline Assafl

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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.
 

Offline Vtile

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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.
« Last Edit: March 06, 2017, 10:30:20 am by Vtile »
 

Offline David Hess

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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
 

Offline W2NAP

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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
 

Offline bji900

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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.
 

Offline grumpydoc

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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.
 

Offline Vtile

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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
 

Offline james_s

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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.
 

Offline Vtile

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Offline Ian.M

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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.
« Last Edit: March 06, 2017, 05:48:38 pm by Ian.M »
 

Offline bji900

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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.
 

Offline Cerebus

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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.
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 
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Offline Kleinstein

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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.
 

Offline james_s

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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.
 

Offline max_torque

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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.)
 

Offline Kleinstein

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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.
 

Offline bji900

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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"...
 
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Offline james_s

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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.
 
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Offline Vtile

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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
 

Offline Assafl

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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.
 

Offline Vtile

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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.
« Last Edit: March 07, 2017, 07:38:33 pm by Vtile »
 

Online wraper

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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
 


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