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Fukushima Reactor: TEPCO robot aims to extract nuclear fuel

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Re: Fukushima Reactor: TEPCO robot aims to extract nuclear fuel

#281

Post by pfdietz »

polotics wrote: post #270
pfdietz wrote: post #260

Earlier quoted context omitted.

It's certainly the case that China has been burning a lot of coal. But that doesn't mean China's PV depends on the existence of coal power to produce it. The objection here seems to be that a renewable economy is impossible because it hasn't sprung into existence fully formed. And isn't coal responsible for all that concrete nuclear plants there are built with? The vision of a nuclear-powered world implicitly assumes…

Where do you see a vision a nuclear powered world? No-one touts that. Look, if you have numbers, actual data, please provide it. So far all you provided pfdietz is sneer and words.

So, if the world isn't going to be nuclear powered, what is your alternative? Sticking to fossil fuels until we're in Permian-Triassic extinction 2, Electric Boogaloo?

If the world and industrial civilization are going to survive, it's either nuclear or renewables.

Re: Fukushima Reactor: TEPCO robot aims to extract nuclear fuel

#282

Post by Manuel_D »

portaouflop wrote: post #110
foxyv wrote: post #66

Earlier quoted context omitted.

To add to your point. Disposal of nuclear waste at sea was common up until 1993. There is still a couple hundred thousand tons of such waste sitting in the ocean right now. In addition, about 214 times as much radioactive material was generated by nuclear testing than the Chernobyl breach. Fukushima wouldn't even come close to the waste that has already been released prior to the 1994 ban on Oceanic dumping.

What is the point ? That we dumped so much crap into the ocean a little more won’t hurt?

Yes. We've dumped tens of thousands of tons of nuclear waste into the ocean, with no observed ill effects. This is very strong evidence that another 900 tons will have no effect either.

Re: Fukushima Reactor: TEPCO robot aims to extract nuclear fuel

#283

Post by Manuel_D »

otherme123 wrote: post #114
portaouflop wrote: post #110

Earlier quoted context omitted.

What is the point ? That we dumped so much crap into the ocean a little more won’t hurt?

And then you have to read about how expensive nuclear is today compared with a few decades ago because of the excesive regulations. Regulations that pro-nuclear usually want to relax, to make nuclear more economically viable. No wonder that dumping nuclear waste to river and oceans is cheaper than having to safely store it for at least a couple of centuries.

Most of the regulations nuclear proponents want relaxed are around plant construction, not waste disposal. The older generations of western nuclear plants have a strong track record. The justification for regulation need to be weighted against the damage of continued carbon emissions due to higher plant costs.

Re: Fukushima Reactor: TEPCO robot aims to extract nuclear fuel

#284

Post by bamboozled »

littlestymaar wrote: post #125
bamboozled wrote: post #82

Earlier quoted context omitted.

What technologies are Japanese companies developing here, and does the tax payer get any of that privately held revenue back in return?

> What technologies are Japanese companies developing here, Do you think the technology already exists off the shelf already? > does the tax payer get any of that privately held revenue back in return? Japan's taxpayers also happen to be Japanese people employed in these companies, so they get their share of that revenues. And the price doesn't even account for the taxes that are paid back to the government directly.

Japanese wages are notorious for being lower that a lot of the developed world and there is a problem with stagnant wage growth.

I don't think there is any need to try justify a screw up on this level as being good. Fukushima was a disaster, economically and for the image of nuclear globally.

Re: Fukushima Reactor: TEPCO robot aims to extract nuclear fuel

#285

Post by bamboozled »

exe34 wrote: post #68
bamboozled wrote: post #54

Earlier quoted context omitted.

Very naive comment. It’s still a lot of money. Are you aware about the current economic and demographic situation in Japan ? It’s not good here. That money could’ve went to a lot more useful things. Also remember this was a man made disaster. The plant was not upgraded (as recommended) to meet new safety guidelines, because, as if a mega tsunami would actually happen, right ? Then right after the event the operator w…

> The plant was not upgraded (as recommended) to meet new safety guidelines, because, as if a mega tsunami would actually happen, right ? And others on this same thread are trying to use the same disaster to paint nuclear as expensive.

The upgrades weren't outrageously expensive, I bet they would've cost 1/100th of what the cleanup costs will be.

We're talking about moving backup generator to the roof level work:

https://carnegieendowment.org/research/2012/03/why-fukushima...

Re: Fukushima Reactor: TEPCO robot aims to extract nuclear fuel

#286

Post by klyrs »

philipkglass wrote: post #24
atomic128 wrote: post #20

Earlier quoted context omitted.

The "super duper radioactive material" you're so afraid of is what's left of the fuel. It's full of energy. The precious fuel is so full of energy that it gets hot ("decay heat"). Without cooling, it melts. Cooling was lost during the most powerful earthquake ever recorded in Japan, the fourth most powerful earthquake ever recorded anywhere. The "Great East Japan Earthquake" and its tsunami killed 19,759 people. The…

The "super duper radioactive material" you're so afraid of is what's left of the fuel. It's full of energy. This precious fuel is so full of energy that it gets very hot ("decay heat"). Fresh reactor fuel is even more full of potential energy but it doesn't get hot because uranium 235 and 238 have very long half lives. Fuel that has been used in a reactor gets hot primarily due to fission products (lighter elements f…

Forgive my ignorance, but isn't that "used pizza box" fuel more or less ideal for a breeder reactor?

Re: Fukushima Reactor: TEPCO robot aims to extract nuclear fuel

#287

Post by dredmorbius »

WalterBright wrote: post #100
cyberax wrote: post #11

Earlier quoted context omitted.

> - OTOH another big earthquake/tsunami can potentially wash it all away and release clumps of radioactive and poisonous metals to the environment...? The reactor itself is high enough to be safe from tsunamis.

If the backup generators had been put on a simple platform, the plants would never have melted down.

I suspect that's not the only SPOF in play.

Nukes, as with rockets, are complex. Many things have to go right and keep going right for them to operate as intended.

(See Rickover's "Paper Reactors" paper for a similar take on this.)

Another factor that contributed not only to Fukushima but other inundations following the Tohoku earthquake was that in response to the megathrust-fault slip, the east coast of Japan sank about a meter lower.[1] Engineers building seawalls failed to take this into account, as I understand.

I'd first realised that such quakes could lower land on the continental plate of megathrust faults when looking over satellite imagery of Banda Aceh after the 2004 Indonesian earthquake and tsunami. Regions along the coast were flooded long after the tsunami had passed, which I realised must have come from a lowering of the land itself.

Seattle and the Pacific Northwest may face similar issue should their Big One occur eventually.

________________________________

Notes:

1. "https://www.sciencedirect.com/science/article/pii/S003808061..." https://www.sciencedirect.com/science/article/pii/S003808061...>

Re: Fukushima Reactor: TEPCO robot aims to extract nuclear fuel

#288

Post by pvaldes »

Dalewyn wrote: post #108
kelnos wrote: post #107

Earlier quoted context omitted.

But that's kinda the point: name one government in the world where politicians don't play political games, sometimes in ways that put their citizens in danger. I'm sure you can't, because no such government exists. "Everything would have been fine if it weren't for the politicians" is not a path forward. These sorts of disasters will continue to happen.

I agree, but then that should not be falsely characterized as a failure of the nuclear industry and technology. The failure was humans, and a very specific subset at that.

> should not be falsely characterized as a failure of the nuclear industry and technology. The failure was humans

Humans working in the nuclear industry are "the" nuclear industry. By definition all economical sectors are arranged around human workers. Remove each human and the industry will lose its reason to exist.

Re: Fukushima Reactor: TEPCO robot aims to extract nuclear fuel

#289

Post by defrost »

pvaldes wrote: post #265
defrost wrote: post #139

Earlier quoted context omitted.

> and 2,202 from evacuation. The primary source for that wikipedia quote argues that the act of evacuating "just in case" caused deaths and that had people remained in place no such deaths would have occurred. Over 65,000 people were evacuated from the vicinity. One such death, for example, was 102 year old Fumio Okubo who lived 30 km inland and hanged himself after being forced to move for no good reason. There were…

> The source argues that the act of evacuating "just in case" caused deaths and that had people remained in place no such deaths would have occurred. We'll never know. Doing history fiction, a more probable outcome would be a lot of people dying by "natural causes" in the next months. We talk about places that were mostly ghost cities for a decade, for some reason. This common discourse of "but nobody died ever by th…

There is a pool of people who definitely died. That's not in dispute.

What is questionable, as you point out, is the application of different tricks and shades of "can't prove, must be nuclear" to claim all deaths in the pool as a direct result of nuclear.

As others have pointed out there are similar yearly figures for tenuous "coal deaths" as there are here for seven years of post disaster "evacuation deaths".

Re: Fukushima Reactor: TEPCO robot aims to extract nuclear fuel

#290

Post by pvaldes »

TheGamerUncle wrote: post #42
ViewTrick1002 wrote: post #18

Earlier quoted context omitted.

The difference is the cost coming from handling it. The latest figure on the cost to handle Fukushima is $190B from 2016. The great thing today is that we don't need to accept radioactive releases from either nuclear power or coal. Simply build the cheap scalable option instead: renewables.

while cheaper in some contexts and somewhat scalable, renewables are nowhere near being as scalable or effective as nuclear, specially as tensions with China rise

Renewables can be destroyed by a war, but it will not take ten years to rebuild and connect it again to the grid when the war is over. Is not only cheaper, but allows a gradual recover of the electric supply. With nuclear a recover is much more rigid and rushing it is potentially catastrophic.
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