Six Years After Fukushima, Robots Finally Find Its Reactors' Melted Uranium Fuel (gizmodo.com) 220
An anonymous reader quotes Gizmodo:
Earlier this year, remotely piloted robots transmitted what officials believe was a direct view of melted radioactive fuel inside Fukushima Daiichi Nuclear Power Plant's destroyed reactors [YouTube] -- a major discovery, but one that took a long and painful six years to achieve... Japanese officials are now hoping that they can convince a skeptical public that the worst of the disaster is over, the New York Times reported, but it's not clear whether it's too late despite the deployment of 7,000 workers and massive resources to return the region to something approaching normal.
Per the Times, officials admit the recovery plan -- involving the complete destruction of the plant, rather than simply building a concrete sarcophagus around it as the Russians did in Chernobyl -- will take decades and tens of billions of dollars. Currently, Tepco plans to begin removing waste from one of the three contaminated reactors at the plant by 2021, "though they have yet to choose which one"... Currently, radiation levels are so high in the ruined facility that it fries robots sent in within a matter of hours, which will necessitate developing a new generation of droids with even higher radiation tolerances.
Friday a group of Japanese businesses and doctors sued General Electric of behalf of 150,000 Japanese citizens, saying their designs for the Fukushima reactors were reckless and negligent.
Per the Times, officials admit the recovery plan -- involving the complete destruction of the plant, rather than simply building a concrete sarcophagus around it as the Russians did in Chernobyl -- will take decades and tens of billions of dollars. Currently, Tepco plans to begin removing waste from one of the three contaminated reactors at the plant by 2021, "though they have yet to choose which one"... Currently, radiation levels are so high in the ruined facility that it fries robots sent in within a matter of hours, which will necessitate developing a new generation of droids with even higher radiation tolerances.
Friday a group of Japanese businesses and doctors sued General Electric of behalf of 150,000 Japanese citizens, saying their designs for the Fukushima reactors were reckless and negligent.
Fukushima was older than Chernobyl (Score:5, Insightful)
I always like to remind people that this thing was older than Chernobyl. This was NOT a modern nuke plant with decent safety features that went meltdown. There is no comparison.
Old enough to predate modern computer analysis. (Score:2, Insightful)
And BWRs were chosen at the time for performance and efficiency, not safety. Plus I am pretty sure those reactors were about 20 years past their accepted usable life, so claiming they are unsafe after operating them far longer than their expected lifespan without doing your own retrofits seems pretty negligent on the part of the owners to me.
If this had failed a few years into the reactor's life, maybe I would agree with them, but they've had 30 years of warning on these exact reactor designs to shut down a
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DNC owned the justice department/FBI for 8 years, had their chance.
Now they can defend and wait.
Re:Fukushima was older than Chernobyl (Score:5, Informative)
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Re:Fukushima was older than Chernobyl (Score:5, Insightful)
I like to remind people that practically all nuke plants are old and don't have decent safety standards, and that it will always be this way because nobody likes to decommission an expensive nuclear power plant if it can be kept online just a little bit longer. Hence Fukushima.
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Which is another good example of why we need effective government oversight, and regulatory agencies with actual enforcement power - despite it being trendy in some circles to claim things would be better if only the government would get out of the way.
Re: Fukushima was older than Chernobyl (Score:2)
Or just mandate that nuclear power stations be fully insured against meltdown etc on the private insurance market. Which would make then instantly uneconomic to operate, if they could even find an insurer willing to take on such insane risk.
impressed and disgusted (Score:2)
Your two "they"s aren't even the same group. The first "they" are the Illiterate Hillbilly Collective. The second "they" are people either: A) already living too close to an operating reactor of an old design, or B) potentially living too close to a forthcoming reactor of modern design.
Second, "truth" is never singular. It might so ap
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Practically all *American* designs are old, and don't have good safety standards. On the other hand the CANDU reactor design is *very* safe, and this has been proven time and again.
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You’re aware that this discussion isn’t about an American reactor... right?
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CANDU does not describe a single reactor, or single reactor design. There are hundreds of CANDU and CANDU-derived reactors in the world and all built 2 or 3 at a time, meaning dozens of variations on this theme.
They are safe designs, and I'm not disputing that. I'm saying that we can't say CANDU is any more or less safe than an American reactor unless we narrow that down some.
This safety of CANDU comes at a cost. They use heavy water which adds to the capital cost, that initial charge of heavy water is v
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Americans have plenty of new designs as well. The problem is the existing reactors that were supposed to be decommissioned 20 years ago but just get continually retrofitted instead because money >> lives or the environment.
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They would have been replaced 20 years ago if the federal government would just issue licenses to build new reactors. I recall reading how a single reactor was held up in getting it's license issued for more than 40 years. FORTY YEARS !!!!!
We can get a natural gas power plant approved in a week, a new hydro dam in a couple years, but it takes a decade to get a nuclear power plant approved. This is not acceptable and we should no longer accept it. We should see these plants get approved in months, not
Re:Fukushima was older than Chernobyl (Score:4, Informative)
Nobody likes to decommission an operating nuclear power plant because they know it will be difficult to replace it once shut down.
As it is now the USA has about 1000 GW of electrical generation capacity, and demand is growing (slowly). A single nuclear reactor will produce about 1 GW of power. No big deal, right? So what if we shut one down? Well, that might be true but there are about 100 nuclear power reactors in the USA, we can't shut them ALL down or the lights go out. Due to the near 24/7 operation of these reactors they have a much larger impact on the grid than just the generation capacity alone might indicate. Even though the generation capacity is 10% of the total they produce 20% of the electricity we use.
Shutting down 2 GW of nuclear capacity is like shutting down 3 GW of coal, 5 GW of natural gas, 7 GW of wind, or 8 GW of solar. If we start to shut down nuclear reactors, and with no new reactor in it's place, that means a lot of windmills need to be erected. That's ignoring the difference between base load nuclear to unreliable wind and solar. We can manage base load nuclear pretty well on a daily and seasonal scale with a few pumped hydro storage dams like the Tennessee Valley Authority does at Raccoon Mountain. Managing this on a hour or minute scale like wind and solar, is a quite different problem. This would be a very expensive problem.
If we want to shut down old nuclear we need to build new nuclear. Anything else means lots of natural gas getting burned, very expensive unreliable energy from wind and solar, or rolling blackouts.
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That's ignoring the difference between base load nuclear to unreliable wind and solar.
You still don't know what base load actually means but continue to torture us with your rants.
Hint: the axis of "base load" to "peak load" and the axis of "undispatchable (unreliable is simply wrong)" versus dispatchable are two axises that don't even cut each other and don't form a coordinate system.
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undispatchable (unreliable is simply wrong)
I know that English is not your first language but what else do you call an energy source that you cannot rely upon to be there when you need it? That's unreliable. Calling it "undispatchable" is just happy mouth noises trying to cover up that it cannot keep the traffic lights running at night.
The word "undispatchable" shows up as a non-word in three of the spell checkers I've tried. A more appropriate word might be "intermittent" which is also just happy mouth noises that mean the same as unreliable.
I h
Re: Fukushima was older than Chernobyl (Score:2)
Let me get this straight... You're posting on the internet, but you're using a spell checker instead of Google to look up a technical term? Let me guess - you drive for Uber, but use a paper map for navigation?
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I like to remind people that 23 of the same stupid GE Mark I reactor design are in use in the USA
Re:Fukushima was older than Chernobyl (Score:5, Insightful)
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design IS terrible, billed as not needing containment building which is the real issue. sure another reactor facility could have failed if put in same place, but would have proper containment. that stupid design was the problem
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yes, a containment *vessel* and it failed 3 out of 3 times in Fukushima, because the design including that vessel is stupid.
Again, no containment building + stupid design = disaster.
Re:Fukushima was older than Chernobyl (Score:5, Informative)
Additionally, the small containment volume and small volume of in-containment water to act as thermal mass gives very poor performance against prolonged, simultaneous failure of containment cooling, and failure of reactor cooling, resulting in heat being dumped into containment. Prolonged total electrical failure was not anticipated at design time, and led to exactly this situation at all 3 fukushima plants. This led to rapid rupture of the containments once reactor cooling was lost. The latest designs of reactor in construction at present have containment volumes approaching 10x that of the BWR1 containment, as a result, pressure rises in accidents would be substantially lower and slower.
This risk was recognised by the manufacturer and the NRC (in their document NUREG-1150), and in 1987, the NRC published a circular to all BWR plants in the US, giving instructions to plant operators, that if reactor cooling is threatened, the plant operators should initiate containment venting as a matter of the highest priority; this would result in a controlled filtered release, but prevent containment rupture and long-term uncontrolled release.
In Japan, this risk was not acted upon. Whether it was communicated by the manufacturer to the government is not public. However, the TEPCO management had a policy where reactor operators were not authorized to initiate containment venting on their own, and required direct authority from senior management. Due to difficulties in communication, it took hours before the request was acted upon. At that point, rather than authorize venting, senior management decided to refer the matter to the government. Logs from the plants show that in all 3 cases, containment pressure dropped substantially before venting was finally authorized, indicating that the containments had ruptured during the delay for authorization.
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No, they only needed to put the walls high enough.
Every coast is a Tsunami region, even if they are more common in some areas and less common in others.
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Yeah, what were those bastards thinking! They should have been able to foresee and use 60 years of future reactor technology development to ensure plants still operating 20 years after their designed lifespan don't have problems!
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Yeah, what were those bastards thinking! They should have been able to foresee and use 60 years of future reactor technology development to ensure plants still operating 20 years after their designed lifespan don't have problems!
The above pretty much sums up the fatal flaw of nuclear power -- a nuclear plant must function reliably for decades and sequester its nuclear byproducts for centuries. Human designers simply aren't up to the task of planning that far into the future, hence even the best-designed reactors sometimes fail due to unforeseen circumstances. That's true of every other technology as well, of course, but in most other technologies the costs of an occasional failure are acceptable.
Re:Fukushima was older than Chernobyl (Score:5, Informative)
Even so -- it melted down. It didn't catch fire and burn for weeks like Chernobyl, because GE designers weren't insane enough to put graphite in close proximity to superheated steam. C + H2O -> H2 + CO
Chernobyl was actually an older class of reactor, even though it wasn't physically older than Fukushima. Based on 1940s plutonium production reactors (and likely, a secondary design consideration was production of plutonium from natural uranium), not really a civilian design.
The Chernobyl design has a few advantages like ability to be refueled while in use (each fuel element had its own steam/water tube that could be isolated) and ability to run on unenriched uranium. But those were outweighed by the disadvantages of the basic design, lack of containment, and poor execution (control rods that increased power when first inserted due to poor design!).
Interestingly, reactors with the same design as the failed Chernobyl plant are still running in Russia proper, though the plants in the former republics and satellite countries have been shut down.
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Indeed, no true Scotsman would ever run this kind of reactor.
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Indeed, no true Scotsman would ever run this kind of reactor.
That's not a no true Scotsman fallacy. You just wouldn't build a reactor like this anymore period. It wouldn't pass any government regulators, IAEA regulations, or any hazard analysis. The only reason these shitty old things are still running at all is because the entire industry was hamstrung into being unable to modernise by greeny psychopaths.
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No matter what issue is raised with any nuclear reactor technology, somebody on this site pops up to say that would never happen if we only used reactors with some different element as fuel, some different physical layout, some different size, some different cooling scheme, yada, yada, yada.
Or they'll blame lack of progress on the "greens".
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Or they'll blame lack of progress on the "greens".
That seems like blame that is well placed. Or have the "greens" changed their minds and support new nuclear power construction now? I do know such exist, I'm pretty sure they are still rare.
Re:Fukushima was older than Chernobyl (Score:4, Insightful)
That's because they're almost always right. Whenever a problem is identified in a nuclear reactor design, manufacturers work to update the designs so that future power plants won't exhibit those problems. As a result, the known flaws in existing reactors have been solved in new designs, and the only thing standing in the way of replacing all those old reactors with reactors based on newer, safer designs are NIMBY pseudo-environmentalists who have somehow convinced themselves that if they prevent new nuclear generators from being built, the need for base load will somehow magically go away.
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the only thing standing in the way of replacing all those old reactors with reactors based on newer, safer designs are NIMBY pseudo-environmentalists
Really, it has nothing to do with the huge cost of writing off those older reactors and decommissioning them, and then building brand new ones?
To give you an idea, the new nuclear plant at Hinkly in the UK is the most expensive object on earth. They couldn't find anyone interested in building it until they offered unprecedented subsidies for its entire lifetime, and even then it wasn't until the Chinese decided to invest that it went ahead. During that time, environmental protests were almost non-existent a
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Re:Fukushima was older than Chernobyl (Score:5, Informative)
Browns Ferry 1, Athens, Ala., operating license since 1973, reactor type GE 4
Browns Ferry 2, Athens, Ala., 1974, GE 4
Browns Ferry 3, Athens, Ala., 1976, GE 4
Brunswick 1, Southport, N.C, 1976, GE 4.
Brunswick 2, Southport, N.C., 1974, GE 4.
Cooper, Brownville, Neb., 1974, GE 4.
Dresden 2, Morris, Ill., 1970, GE 3.
Dresden 3, Morris, Ill., 1971, GE 3.
Duane Arnold, Palo, Iowa, 1974, GE 4.
Fermi 2, Monroe, Mich., 1985, GE 4.
FitzPatrick, Scriba, N.Y., 1974, GE 4.
Hatch 1, Baxley, Ga., 1974, GE 4.
Hatch 2, Baxley, Ga., 1978, GE 4.
Hope Creek, Hancock's Bridge, N.J. 1986, GE 4
. Monticello, Monticello, Minn., 1970, GE 3.
Nine Mile Point 1, Scriba, N.Y., 1969, GE 2.
Oyster Creek, Forked River, N.J., 1969, GE 2.
Peach Bottom 2, Delta, Pa., 1973, GE 4.
Peach Bottom 3, Delta, Pa., 1974, GE 4.
Pilgrim, Plymouth, Mass., 1972, GE 3.
Quad Cities 1, Cordova, Ill., 1972, GE 3.
Quad Cities 2, Moline, Ill., 1972, GE 3.
Vermont Yankee, Vernon, Vt., 1972, GE 4.
This was from five years ago. Didn't check to see how many ar still operational but they're definitely old.
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Installed at many US sites (Score:2)
I always like to remind people that this thing was older than Chernobyl. This was NOT a modern nuke plant with decent safety features that went meltdown. There is no comparison.
So often we've been reminded that the 'positive void co-efficient' safety feature of these reactors made a Chernobyl style explosion impossible, yet it happened. Rendered ineffective because TEPCO by-passed requirements to operate the reactors safely.
It's reasonable to remind people it's the same type of reactor installed at Fukushima [wikipedia.org] is operating in many locations throughout the U.S. [nrc.gov]
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for maximum safety, you want a negative void coefficient.
i.e., you want output power to reduce by design when voids (from steam bubbles) develop in the cooling system.
Chernobyl actually had a positive void coefficient, one of many design issues that lead to the accident.
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Old it may be, but to this day a number of reactors similar to the GE model that melted down continue to be run around the world and in the US. In fact there's one not far from where I live: the Pilgrim Nuclear Power station has the same GE BWR-3 with Mark 1 containment as Fukushima Daichi 1.
Chernobyl's vintage is neither here nor there; it is an entirely different Soviet design in a completely different design lineage.
But where both Fukushima and Chernobyl are relevant is the role that managerial miscondu
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Which is why much of the development in nuclear reactor technology has focused on physics-based shutdown modes rather than relying on human or even mechanical intervention when something goes wrong.
But none of that helps existing reactors that are still using previous generation technology too much.. and yeah, human error is a huge ongoing concern with those. I'm sure people are a lot more cautious in the wake of Fukushima, and will be as long a Fukushima keeps popping up in the news once in a while.. but
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The plants in Chernobyl and Fukushima are completely different designs and based on completely different technologies.
It does not matter which one is/was older.
This was NOT a modern nuke plant with decent safety features that went meltdown.
That is completely irrelevant. Fukushima melted down because it hat no cooling, due to misplaced emergency power generators. It bottom line had nothing to do at all with the design of the plant itself.
However it is astonishing that they where not able to bring a ship in f
Re:Fukushima was older than Chernobyl (Score:5, Informative)
The failure was loss of power to run the plant's cooling systems. Basically, the tsunami swamped the backup power generators and contaminated the diesel fuel reserves for the generators. The destruction of the surrounding roads prevented new generators and fuel from being brought in in a timely manner. And when they eventually did arrive, workers discovered the power couplings for the trucks were different from the ones the plant used, and they had to gerry-rig a connector. All of this took critical time which could've mitigated the severity of the accident. This wasn't an explosion like Chernobyl, it was a gradual event as the cooling water slowly evaporated allowing the fuel rods to melt.
A single diesel generator situated on higher ground with an independent fuel source could've prevented the entire accident. Instead, in stereotypical Japanese fashion, they placed all the generators in a neat row right next to each other in the basement, where the tsunami swamped all of them simultaneously. See, the thing about redundant backup systems (e.g. multiple generators in case some do not function) is that they have to be different to be redundant. If they're the same model, in the same location, using the same fuel source, then any single event which affects one generator will affect all the generators, defeating their redundancy. In fact the two newer reactors at Fukushima on higher ground were just fine because their generators and fuel supply worked as intended. They just didn't have a really long extension cord to reach from those generators to the problem reactors. Basically the failure at Fukushima was the same as when you store your backup drive next to your computer (although the consequences were much more severe). If your house burns down or you're burglarized, both your computer's main drive and your backup drive will be lost. Because you're storing both in the same location, the redundancy of a second copy is defeated by any event which affects that entire location.
Fukushima wasn't a failure of nuclear power. It was a failure of backup (non)redundancy which had nuclear consequences. Basically, because of unwarranted paranoia about nuclear power, everyone concentrated on going over the nuclear parts of the plant with a fine-toothed comb to make sure it was safe. As a result, the non-nuclear backup systems didn't get enough scrutiny, and that's what failed.
It's like airliner safety. Air travel is already far safer than other modes of transport. But because any airplane crash gets disproportionate news coverage, we spend billions of dollars trying to reduce the couple hundred airliner deaths per year even further. Meanwhile the tens of thousands of people dying each year in car accidents gets very little attention. Even including the estimated future cancer deaths from Chernobyl and Fukushima, nuclear power [forbes.com] is still the safest power source we've invented [nextbigfuture.com] (yes, safer than wind and solar [iaea.org] based on both on deaths and lost man-days per unit of electricity generated).
Re:Fukushima was older than Chernobyl (Score:5, Informative)
The nuclear parts of the plant itself survived both the earthquake and tsunami just fine even though both events were well beyond the plant's design specifications.
That is incorrect. The plumbing for the cooling system was damaged by the earthquake. The tsunami damage made it impossible to check it in the aftermath, and the fault went unnoticed until it was too late.
That fault, specifically a key valve stuck in the wrong position, meant that the water that was pumped in to cool the reactors from fire engines was diverted to storage tanks. If it had reached the reactors then the explosions and meltdowns might have been avoided.
Fukushima wasn't a failure of nuclear power. It was a failure of backup (non)redundancy which had nuclear consequences.
To two are inseparable and for all intents and purposes one and the same.
But because any airplane crash gets disproportionate news coverage, we spend billions of dollars trying to reduce the couple hundred airliner deaths per year even further.
Is it that, or is it because the potential consequences of a disaster, like an aircraft going down over a city, are very serious? Also, the cost is relatively small compared to the profitability of running an airline. The main issues they have are fuel/pollution, noise and airport capacity. Safety costs come pretty far down the list.
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The plumbing for the cooling system was damaged by the earthquake. :D ... no idea which.
That is incorrect, too
There are pipe damages
Main problem was: no power. The plant relied on power from the grid. But the grid was gone as the earthquake destroyed the masts of the power grids.
So it relied on the emergency power generators, which were flooded by the tsunami.
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They had emergency power on site, in the form of batteries and mobile generators, fairly quickly. They had emergency pumps (fire engines) on site quickly too, certainly in time to stop the disaster. They failed to work because of earthquake/tsunami damage.
Re:Fukushima was older than Chernobyl (Score:5, Informative)
Fukushima wasn't a failure of nuclear power. It was a failure of backup (non)redundancy which had nuclear consequences. Basically, because of unwarranted paranoia about nuclear power, everyone concentrated on going over the nuclear parts of the plant with a fine-toothed comb to make sure it was safe. As a result, the non-nuclear backup systems didn't get enough scrutiny, and that's what failed.
If you read The Official Report [nirs.org] you will find that it was a belief system that nuclear power was a safe high tech energy source that appropriate upgrades weren't performed to the installation due to collusion between the Operator (TEPCO) and the regulator (NISA and NSA).
This shows the dangers of dogmatic skepticism, social proof and imposing a idealistic belief system onto the nuclear industry.
The Fukushima accident shows that the nuclear industry learned nothing from the Chernobyl accident, which is also a conclusion made by the report.
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No, this shows the dangers of regulators and operators prioritizing their own benefit over public safety. (That is stated multiple times in that report.) That report finds things almost entirely related to corruption and dysfunction in Japan's nuclear industry and regulation: "NISA (the regulator) did instruct TEPCO to conduct an anti-seismic backcheck, but by not completing the backcheck as originally scheduled, TEPCO effectively invited the accident that followed." The regulator should have put TEPCO ou
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though both events were well beyond the plant's design specifications.
No they where not.
The plant is designed for a 6.5 quake or something. And that is exactly what happened at the plant site, probably weaker. The 9.3 quake was 450miles away!
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It was upgraded, several times. There were also upgrades in the pipes for other things relating to safety. The earthquake hit *before* that happened. Don't forget that anything nuclear related is a hot-topic in Japan which has a very active and aggressive anti-nuke circle of environmentalism. NIMBYism and lawsuits hampered a lot of what was going on, that doesn't absolve TEPCO of liability, but sometimes people are their own worst enemy. Let's look at a different situation, in a different country like
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Which proposal specifically are you talking about? From what I can tell the delays have been mostly due to expensive accidents at other plants needing to be understood and mitigated, not to mention changing the economics of the new plant each time.
Economics are what has killed off the nuclear renascence. Renewable energy got cheap really fast, nuclear just gets more expensive as new failure modes are found, and the promises of new designs and things like thorium don't pan out.
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Renewables didn't get cheap really fast in North America. The price per kWh is still double to quadruple(market cost to break even is $0.20-0.83kWh) the rate that a nuclear reactor here has for the "refueling and refitting" cost in it's last 10 years of production life(around $0.08kWh). The only 3 power production methods that are cheaper are hydro-electric(0.04kWh), natural gas(0.05kWh) and coal(0.03kWh). In North America, it's cheaper to build a dam, flood huge tracts of land, and be profitable in less
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Yeah, forget about combat robot competitions, this is a whole new challenge.
Which bits are the fuel? (Score:2)
Watched the video but there is no annotations or sound. Does anyone have any better ideas as to which bits are fuel?
To me they could just be driving around a sunken ship for all I can identify.
they'll keep it (Score:5, Interesting)
Re:they'll keep it (Score:4, Informative)
The idea was to make it possible for the residents of nearby towns to go back. Aside from anything else that is the cheaper option; if people can't go back then they will have to be compensated for everything. Property, businesses, jobs, farms...
Until the plant is safe that can't happen. There is also the decontamination, which has been going pretty badly. But since legal decisions are making it look like full compensation is the only option anyway you could be right, it might just become a write off. I'm not so sure though, I think national pride will require it to be cleaned up.
Re:they'll keep it (Score:5, Informative)
It would be fun to be able to design these bots, though that is not a task my company does. Still, I wonder if we can't go ultra simple? What about something like a bot based only on hydraulic lines, with a fiber optic camera? Can you pass a video image with pure fiber and no electronics? I'm assuming the hydraulic fluid could be controlled by a pneumatic valves. By using air to control movement, you don't need a return line for it. That leaves you with a fiber optic bundle, a send and return hydraulic line, and some smaller bundle of low pressure air lines.
It has been discussed.
The major issue is that the amorphous microscopic structures are particularly prone to radiation induced discoloration of the fiber optic lines. This is worse for the transparent and translucent thermoplastic copolymers, such as methylmethacrylate or polycarbonate.
You'd be replacing the optical fiber fairly frequently, particularly if it were a modern plastic, rather than true glass, although glass will have similar issues.
You end up with coloring in both the visible light regions, and in the IR and UV bands.
This is commonly known as "browning".
While technically, you could throw a laser through the fiber to heat and/or otherwise cause fading.
However, it's going to happen in and around 10^10 Rad.
You can read the original paper by W.H. Cropper here; it was published in 1962:
http://onlinelibrary.wiley.com... [wiley.com]
[Note: fees may be involved, if you access this through the Wiley site]
International problem (Score:2)
We need an international effort to resolve this issue. The international community can bring a lot more resources and focus to resolving the issue than TEPCO can.
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Resolve what issue? TEPCO is perfectly capable of handling the local clean up (whether they want to or not is another question..) Of course there's only so much that can be done no matter what resources you have (for example, trying to relocate the reactor core is probably not a thing that will ever happen.. trying to move it would expose the environment to far more radiation than just leaving it where it is and capping it in concrete like they did at Chernobyl.)
The larger issue of ancient reactors still
Info... (Score:5, Informative)
I'll just repost my comment from Gizmodo here, some info to kill some potential myths.
It’s bad, and it’ll probably take a long time to be solved... ultimately getting to some point similar to Chernobyl. Not in the same scale I mean, but like years from now they’ll just encase the whole thing in concrete and abandon it there because there’s not much else to do.
Let me tell something about this for people that might be reading and getting a wrong picture out of it, because I also did and just learned recently about some stuff. People should know that for the vast majority of Fukushima prefecture, life remains going like normal. The area affected that people had to evacuate was a radius of around 20 to 30km (12 to 18 miles), which is of course still a lot, but just a small fraction of Fukushima as a whole, which has almost 750 square kms (288 square miles).
It’s nothing to laugh about, but I think some people imagine something like the entire prefecture, or half of Japan being a radiation infested zone or something. Fukushima is the 20th out of 47 prefectures in terms of population, 3rd in area, the capital city wasn’t affected.
I was watching a channel that made a tour around major onsen cities in Fukushima, awesome stuff. Radiation wasn’t a concern, even when they went to a coastal city about an hour away from the power plant.
Again, it’s not to diminish how serious the disaster is, but the thing is, we get a whole lot of reports talking only about the disaster zone, so much that it seems that it’s a huge area that is unlivable. It’s not.
Re:Info... (Score:4, Interesting)
I'm afraid your numbers are off. The prefecture of Fukushima has about 13,750 sq km. 750 is less than the area of that 20km evacuation circle.
Your point, however, is well taken.
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Fukushima had other interesting effects that are hardly ever mentioned.
The "nuclear renaissance" died that day. It was already looking shaky because of high costs and increasing competition from renewables, but Fukushima really was the death knell. In the short term everything paused while people tried to figure out what went wrong and make sure it couldn't happen again, and in the longer term it caused the focus for clean energy to move elsewhere.
Japan lost all its nuclear power in one day. All plants offl
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I'm going to go ahead and disagree with you on that. Sure there was a couple of panic buttons pressed when Fukushima happened, especially in Europe, but at the same time China is constructing a huge number of new plants to meet their ever-growing energy needs without further damaging their environment (barring their own meltdown of course, but I'm going to assume that they're using one of the more modern designs that significantly reduce the possibility of that happening.)
At the end of the day we still hav
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https://en.wikipedia.org/wiki/... [wikipedia.org]
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All new nuclear approvals in China were put on hold indefinitely in 2011. The only plants being built there were approved and started before 2011.
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Of course given the choice you wouldn't do it that way, but it proved something important. It proved that nuclear was not essential, which greatly strengthened the anti-nuclear movement's arguments.
If nuclear was not essential then why is Japan building new nuclear power reactors now? They expect to have 20% of their electricity from nuclear by 2030, at least that's what I read on Wikipedia.
Large nations like the USA, Canada, and Russia, can spread wind and solar power over large tracts of land to avoid localized effects like weather and daylight shifting. Japan is an island nation that is on not so friendly terms with the nations on the nearest large land mass. Their hydro power is limited and wav
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That is the problem with you americans. ... e.g.
To (1) dumb to look on a map and not informed about (2) technology that is developed outside of the USA.
1) Japan is a chain of islands that is about 2000km long. It is impossible that they have not enough wind
2) Their hydro power is limited and wave power is not a developed energy source yet. Both wrong.
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I actually wrote a (short, I''ll admit) report in college about the power grid in Japan. They barely have the infrastructure now to keep the north islands connected to the south islands reliably. To get them to produce enough wind AND have this transmitted reliably across their nation would be quite expensive. The north and south divide is actually two separate power grids, one running 50HZ and the other 60HZ.
This is far from trivial. You can claim that the wind always blows somewhere in Japan but that
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In fairness, The US has vast amounts of essentially flat space where you can easily build and maintain large solar or wind farms. Japan doesn't have that feature.
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There are no new nuclear plants being built in Japan at the moment. Everything was put on hold in 2011. There was one plant that was due to start construction in 2016 as an extension of an existing one, but it is still paused.
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It’s bad, and it’ll probably take a long time to be solved... ultimately getting to some point similar to Chernobyl.
They will have to dismantle the reactors.
Not in the same scale I mean, but like years from now they’ll just encase the whole thing in concrete and abandon it there because there’s not much else to do.
The main issue is the ground water and the amount of highly radioactive water the site leaks. Encasing the site in concrete will not solve that problem so it has to be dismantled.
The site continues to leak about 400 tons of highly radioactive water into the Pacific each *day*, that's 876000 tones of radioactive water so far, and climbing.
Inevitably this accumulates in the food chain so the sooner we resolve the situation the less damage will be done to the human g
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The Pacific weighs, as a very rough estimate from some Googling, around 7.5x10^17 tons. Your 876000 tons of waste is a bit over one ten billionth of a percent.
I certainly wouldn't want to eat any local fish from that region (dissipation rates certainly aren't that fast!) but the overall effect outside of that region is minuscule.
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Inevitably this accumulates in the food chain so the sooner we resolve the situation the less damage will be done to the human genome and our foodchain.
What elements are producing this radioactivity? As I understand it the largest source, as far as the ground water is concerned anyway, is tritium. Tritium has a half life of 12 years. Tritium is a naturally occurring element, life evolved with it in the environment, so it's not near the risk that other radioactive elements might pose. It exists as heavy water and so it just mixes in the ocean, with all the rest of the heavy water on Earth.
All the radioactive iodine in the water, which had people freakin
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As I understand it the largest source, as far as the ground water is concerned anyway, is tritium. ... in a burned down reactor? ... in the ground water?
That shows exactly how dumb you are. You _understand_ nothing about anything that has something to do with "nuclear".
Tritium
Tritium
Hint: you can look up what Tritium is on Wikipedia. Or in a book about Chemistry.
All the radioactive iodine in the water, which had people freaking out at the beginning, is effectively gone now. ... and how does the Iodine
Wow
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Rather than just mock my ignorance how about you inform me?
How does the iodine know my ideas? It doesn't know, it tells me. The half life of iodine means all but trace amounts decayed to inert xenon by now. I say "effectively gone" because any radioactive material cannot be said to every be truly gone but it's "effectively gone" because it would take the most sensitive instruments we have to see it's there.
Go look up tritium on Wikipedia yourself, there's a section on Fukushima there. This tells me you
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there’s not much else to do.
They could throw a clean carefully designed H bomb in that area, radiation will be gone.
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http://fukushimaontheglobe.com... [fukushimaontheglobe.com]
The citing of the plant was certainly negligent (Score:5, Informative)
Fukushima's site was dug down to make it easier to build. Just up the coast, closer to the epicenter, Onagawa was built higher above the water line, and they even included a basin to maintain an ocean water supply to the safety related pumps for the duration of a tsunami. They escaped the Earthquake and Tsunami largely undamaged. In fact, Onagawa [thebulletin.org] actually served as shelter after the Tsunami.
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If they had just put the backup generators on higher ground, things would not have been as bad.
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The problem is that nuclear plants are so expensive there is great reluctance to shut them down when it becomes apparent that they are not as safe as was originally thought. It's still happening with other plants, where re-examination after the March 2011 disaster has determined that there were previously unknown faults or flood risk in the area.
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Warranty Period on Nuclear Reactors? (Score:5, Interesting)
The two questions I have is why was Fukushima still active after 30 plus years? What exactly is the warranty period for nuclear power plants.
I would love to get a 30 year warranty on my car or phone. I see they are trying to sue GE... Who issued permits in Japan for this plant? Typically responsibility shifts to the operator after power plants are completed and functioning well since regardless of design or workmanship you can easily destroy a power plant through incompetence or insufficient maintenance.
It is also interesting that the reactor survived the quake it'self but was essentially destroyed by the tsunami.
There is this concept in liability law called Act of God. The Japan Tsunami qualifies if anything ever did. That event killed 15,894 people in a first world country, and as far as I am aware is the highest death toll event in a first world country in at least 70 years outside of war. The Tsunami wave reached a peak height of 133 feet. That is Biblical level apocalyptic disaster right there.
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Licensing time in the US is typically 40, often extended to 60 years.
With expensive items (buildings, factories, trains, aircraft, etc), lifespans of this type are typical.
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IIRC, extended to 60 years, but only after a major refit and re-licensing process.
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License to operate and expected lifespan I can agree should be long as you describe, but I would be shocked at more than a 5 year warranty period from the builder. Things wear out and in capital equipment especially it is up to the owner to follow the PM schedule or suffer the consequences.
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but I would be shocked at more than a 5 year warranty period from the builder
Then be shocked.
In Europe by law large constructions have a warranty of minimum 30 years.
A nuclear plant falls in that category. Actually every power plant or bridge does. So does a sea going ship or an air plane.
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The two questions I have is why was Fukushima still active after 30 plus years? What exactly is the warranty period for nuclear power plants.
TEPCO voided any implied warranty by not operating the installation according to the criteria GE specified. Thus they exposed two Design Basis issues, which created hydrogen and caused the explosions.
There is this concept in liability law called Act of God. The Japan Tsunami qualifies if anything ever did.
Not really, the reactor was rated to 600Gal for earthquakes and survived the quake. The operator installed back-up generators where they could be flooded and did not perform the upgrades to the sea wall to protect it from a Tsunami.
Not an act of God, it's an act of Criminal Negligence by the board of TEPCO
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The 2004 Tsunami in Asia killed close to 300,000 people, in various countries: https://en.wikipedia.org/wiki/... [wikipedia.org]
That is Biblical level apocalyptic disaster right there. ... in old times they marked the hight with marking stones. It was well known that the walls/dams of Fukushima were below the marks.
There were higher tsunami in Japan
Re:Warranty Period on Nuclear Reactors? (Score:5, Informative)
If your car or phone was built to the same standards, and had proper maintenance applied throughout its lifetime, it would last a lot longer as well. Of course you would be using a 30-year old car or phone, something you would probably consider to be completely unacceptable: the car uses far too much fuel and doesn't have any modern safety features, and the phone doesn't do any of the things you'd want a phone to do. The same is true for nuclear plants: we have much safer designs now.
Unfortunately we cannot build them, because of the great success of the anti-nuclear lobby.
It's a bit of a shame really. If we had continued building nuclear plants we might even have avoided the whole climate change discussion - or we might have been worried about global cooling, and discussing how much CO2 we need to release into the atmosphere to keep the temperature comfortable. But hey, at least the environmentalists won that round...
Re:droids with even higher radiation tolerances (Score:5, Funny)
As long as there’s a smelter nearby, so if necessary we can trick the robots into falling into big vats of molten metal, we’ll be fine.
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A few days later they were relabeled Walking Ghosts [wikipedia.org].
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No kidding.
What really blows is that for a few hours, maybe even a day or two, you feel like you're actually getting better, even though you're certainly going to die.
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Fiberoptics become opaque when exposed to severe radiation for extended periods. You can't be exchanging fluid with your robot and you can't be replacing seals. So you could use pneumatics, but no existing control system permits for fine control of any kind with all the control hardware on the controlling end using pneumatics, that's a difficult problem.
I propose really fancy-pants bowden cables to solve the motion problem. I don't have a solution for the glass problem. Bowden cables are cheap enough that y
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When I worked the first time with "robots" and automatic machines around 1986/1987 they all were pneumatic (air, not oil). ....
I doubt the technology degraded over the last 30 years so much