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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

#321

Earlier quoted context omitted.

https://de.wikipedia.org/wiki/Untertagedeponie_Herfa-Neurode https://de.wikipedia.org/wiki/Deponie_Ihlenberg

I cannot read German, Google Translated it, and could have misunderstood but could not find how those waste sites may trigger such major accident, nor about untreatable waste and one of them stores nuclear waste ("from the Greifswald nuclear power plant")! Chemical industry also produces very dangerous waste (Seveso...), I agree. This cannot serve as an excuse for nuclear, especially as, nowadays, we know how to indu…

Sorry.

Unfortunately the two sites have no english entries in Wikipedia, I just put them there because they are the two largest, but still mostly unknown to the general population.

With the exception of the locals, who fear for them leaking into their groundwaters. Which may be unfounded for Herfa-Neurode because that is sitting in a real stable formation, for now...

...which says nothing about larger timescales, which we are dealing with here, because much of the stuff stored there has no 'half-life', and is way nastier than anything which caused Seveso.

The other site, Ihlenberg, formerly called "Schönberg" ('nice Mountain', get it?) has a more interesting history. It's located right next to the former border between West-Germany and East-Germany, seperating them from the end of WW2 until reunification.

In those times they buried much western trash for money in rather 'hush-hush' and corrupt ways there. The nastiest ones. They were poor and needed the money. What exactly, and how much, at which position und which conditions is still unknown, and not easy to assess, because that probing would disturb the other nasty stuff which it is embedded in.

The fear there is much more founded, because it happend in rather uncoordinated ways, because of the 'hush-hushness' due to corruption, and that site is not stable. If it leaks, it has the potential to poison the whole Bay of Lübeck.

It also sits on something like a geologic fault line roughly spanning from Kiel in the Northwest to there, caused by glacial rebound of Scandinavia. Slowly and gentle for now, but one never knows, right?

That was that. As to an excuse for nuclear...

Do you really think all that oh so sustainable green shit is growing on trees? Maybe look into so called 'superfund sites' in the USA, and how they overlap with semiconductor production sites, which also applies to solar cells. Japan should have had some of those 'oopsies', too. But probably not spoken about, because the nail that is standing out has to be hammered in, right?

Wind? How long do they last? What's with the abrasion of the (mostly the front edges) blades while they operate and the entry of those stuff in form of microplastics into the environment?

Their disposal after use?

The large fundaments they need in the form of concrete, and the OH MY GAWD ALL THAT NASTY CARBON!1!! that is causing? Not to speak of the disturbance of ground water tables, when they have to go 15 to 40 meters (or even more) deep for stability.

Geothermals? You have much of that. Why is it used so rarely?

Sayonara.

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

#322
post #257

Earlier quoted context omitted.

Google is free but you linked to a prototype and a “will be” article rather than proven results.

they did build the stuff, so 'catching up' is a pretty correct statement. I didn't say they catched up, for that they'll need much more time and effort, but they do have progress

It’s still a non-answer to the original question. Look, we all get that you’re a fan and there’s nothing wrong with that (especially here) but overstating things does not help the cause. Nuclear power proponents often act like there’s some conspiracy to suppress the technology when basic economics is a simpler explanation. In this case, it’s great that progress is happening but it’s still the case that if our goal is decarbonizing you’ll see almost immediate reductions taking the same money and bringing renewables online a decade or more sooner. That doesn’t mean that we shouldn’t consider nuclear for some of the edge cases but there’s still too much R&D needed for it to be a primary source.

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

#323

Earlier quoted context omitted.

SMRs are being touted now, but (1) they aren't that small, and (2) they have to be grouped together or else fixed labor costs become unacceptable per unit of power output. The result is a collection whose power output isn't too different from conventional large reactors.

I agree it’s unlikely but by the same token renewables don’t really solve this problem any better - at the end of the day you need batteries for both.

Renewables scale down much better than nuclear does, particularly PV. For that matter, so do batteries.

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

#324

Earlier quoted context omitted.

Fukushima could have been easily predicted. That’s what passive safety is about.

> Fukushima could have been easily predicted After such an accident some armchair experts are quite sure that it "could have been easily predicted". Before the accident (to "easily" prevent it) or during it they are nowhere to be found. https://news.ycombinator.com/item?id=41774144

I won't try to summarize here, but long story short, the conditions which led to the Fukushima disaster were well known and TEPCO was warned as early as 2000, but they did nothing to prevent it. There a number of good sources on the Wikipedia page (https://en.wikipedia.org/wiki/Fukushima_nuclear_accident#Pri...).

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

#325

Earlier quoted context omitted.

And that's different from "it was replaced by coal". You should probably have started with a correct statement, not a falsehood that you had to rephrase into a correct statement.

in the end it's the same. Replaced with coal&gas = more coal&gas was used than it would have been needed with nuclear on

Which again is a completely different argument than what you started with. The argument was that nuclear power was replaced with coal and gas.

As we've concluded it evidently was not. Both coal and nuclear power has been replaced with renewables.

I would suggest you stop spreading falsehoods.

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

#326
post #237

Earlier quoted context omitted.

The Oroville Dam crisis could have been avoided if the power plant did proper maintenance on the dam, and the power plant management was found as being the primary cause of the accident. Dams are in general man made and maintain multiple nuclear bombs in terms of energy in potential, which need to be handled with care. The crisis had as much to do with the weather as Fukushima had to do with earthquakes. Much of the…

The Oroville Dam didn't collapse and the crisis didn't make a single victim Is there a debate about those raw facts? https://damfailures.org/case-study/oroville-dam-california-2... > handled with care > proper planning and prevention I agree. Everyone can fail. Letting very dangerous tiny material undetectable without a complex equipment and active for years getting out then be dispersed on huge areas by wind/rain/..…

How can you claim that there wasn't a single victim when they evacuated 180,000 people (including hospital inpatients and elderly people)? If we use the same evacuation-to-death ratio as Fukushima, the Oroville Dam crisis caused 2416 deaths. In addition it should have costed the government hundreds of millions in evacuation costs, repairs of infrastructure, and lost revenue because of damages cause by the spillway.

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

#327

Earlier quoted context omitted.

> The failure was humans Isn't it always true, for such matters? As we cannot avoid committing errors it seems better to prefer a way without any risk of major accident (very dangerous radioactive things, difficult to cleanup, travelling long-distance thanks to wind, rain...). No wonder renewable sources quickly gain traction.

Characterizing the failure of politicians as a failure of nuclear power is the error in logic I am talking about.

You cannot separate the human equation from the technology.

As I said: "The big problem with nuclear is not technological, it’s guaranteeing that whoever is responsible for it will be competent, capable and solvent for hundreds of years."

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

#328

Earlier quoted context omitted.

The government was no more or less inept than any other organisation - government or private - anywhere in the world. When faced with pressure to save money but still deliver, weighed up against a very low risk of catastrophe in their time, they did the mental math and cut corners, found ways around the safeguarding policies previously put in place and kicked infrastructure spending down the line. The big problem wit…

It wouldn't have cost hardly anything to have a pipe so the hydrogen could vent outside rather than inside, which resulted in a detonation.

And yet it was not. Can you guarantee that the operating board resposible for a future reactor would not make a similar mistake?

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

#329

Earlier quoted context omitted.

It is not about how much it can store. You cannot wish away the charging losses. There are no losses to pumping gas into a tank. Nor can you wish away the losses in the charger itself. Converting AC to DC is hardly 100% efficient.

In that case, you should also not wish away refining losses, where petroleum is turned into gasoline and other fuels.

If you want to get an accurate accounting of CO2 emissions, sure.

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

#330

Earlier quoted context omitted.

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…

There are a number of cheap-as-dirt things that could have been done to prevent the disaster. Putting the generators on a platform was one. Venting the hydrogen outside instead of inside, another. Having emergency repair parts on site is a third. Having a gravity-fed way to cool the reactors with external water, a fourth.

And so on.

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