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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

#341

Post by natmaka »

rbanffy wrote: post #320
natmaka wrote: post #311

Earlier quoted context omitted.

> 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

“What happens if we lose the generators?” is not a hard question to come up with. I have a great imagination and a long career built on, among other things, asking pointed questions. I would have asked that very same question, as well as “how unlikely?” as the next one.

> “What happens if we lose the generators?”

They knew. Especially after Forsmark, 2006 ( https://en.wikipedia.org/wiki/Forsmark_Nuclear_Power_Plant#J... ), which was a major subject for the industry. The first stages of a similar incident happened in France decades before.

... and it didn't change anything.

https://news.ycombinator.com/item?id=41774144

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

#342

Post by natmaka »

belorn wrote: post #326
natmaka wrote: post #302

Earlier quoted context omitted.

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.

Oroville: no radiation, no panic. The evacuation started on February, 12 and people were back home 2 days later. Moreover such event in the USA in 2017 caused deaths and nobody took note?

Come on.

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

#343

Post by natmaka »

LargoLasskhyfv wrote: post #321
natmaka wrote: post #291

Earlier quoted context omitted.

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, whi…

Thank you for those details. This is even worse than I understood.

As already stated by Kon5ole: we get the benefits and future generations gets the burden.

Nuclear (decommission, hot waste...) plays the same game.

> Do you really think all that oh so sustainable green shit is growing on trees?

No, but AFAIK we know ways (some are expensive) to alleviate part of their burden and the net result cannot be matched by other type of sources.

> Wind? How long do they last?

It depends. https://www.tvindkraft.dk/stories/a-new-nacelle-back-end/

> 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?

Nothing is perfect. Nowadays a coating is used ( https://weatherguardwind.com/leading-edge-erosion/ ).

> Their disposal after use?

https://news.ycombinator.com/item?id=41783908

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

Because in some places it can trigger earthquakes. Renewables is a set of solutions, none is perfect (one-size-fits-all). https://en.wikipedia.org/wiki/Nirvana_fallacy

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

#344

Post by rbanffy »

natmaka wrote: post #341
rbanffy wrote: post #320

Earlier quoted context omitted.

“What happens if we lose the generators?” is not a hard question to come up with. I have a great imagination and a long career built on, among other things, asking pointed questions. I would have asked that very same question, as well as “how unlikely?” as the next one.

> “What happens if we lose the generators?” They knew. Especially after Forsmark, 2006 ( https://en.wikipedia.org/wiki/Forsmark_Nuclear_Power_Plant#J... ), which was a major subject for the industry. The first stages of a similar incident happened in France decades before. ... and it didn't change anything. https://news.ycombinator.com/item?id=41774144

It's very easy to predict something that already happened will happen again.

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

#345

Post by foxyv »

Manuel_D wrote: post #282
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?

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.

I don't think that's how it works. For all we know, in ten years, parts of the Atlantic Ocean could become uninhabitable by marine life due to radioactive plumes. Or not. The history of radioactive waste disposal is very short. Dumping further could exacerbate future problems. That's kind of why we banned it.

Personally I think deep bore hole disposal in geologically inactive regions makes the most sense.

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

#346

Post by Krasnol »

Moldoteck wrote: post #313
Krasnol wrote: post #261

Earlier quoted context omitted.

Those are all things that take a looong time and cost a hell lot of money, which could be turned into electricity in 2 years if you'd spend that taxpayer money into renewable technology. The war will be probably over before those countries dependent on Russia will become self-sufficient. This is desperate, keeping alive an outdated technology. France slept on the change and now has to do everything to keep the show r…

scaling is expensive. France too, for enrichment is doing scaling of what they already did, just like Germany (I'm referring to german enrichment plant) :) Nuclear is not an outdated tech, why do you say that? Especially the ap1000 reactor. France slept on building more nuclear and was on path to ditch it, reversed only recently, that's why they are where they are, still - in much better shape than Germany in this re…

Westinghouse went bankrupt over that new reactor, and wasn't it supposed to be more cost-effective?

Nuclear has peaked, and its share knows only one way. Down [1]. It neither has become in any way more significant better nor has it become cheaper or faster to build.

Meanwhile, renewables, got better, cheaper and faster to build.

Nuclear is tech from the past. We needed it once. Now it's clogging up the grids, wasting taxpayer money and leaving waste behind for generations to care about.

[1] https://ourworldindata.org/grapher/share-elec-by-source

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

#347

Post by wildzzz »

rtpg wrote: post #106
duskwuff wrote: post #89

Earlier quoted context omitted.

You might be thinking of temperature ratings, which are indeed just based on more stringent testing. Radiation hardening is, well, harder . It typically means some combination of different semiconductor processes (often silicon-on-sapphire and/or larger feature sizes) and added internal redundancy (ECC memory, TMR, watchdogs, etc). All of these require that the rad-hard parts be manufactured separately from the comme…

it definitely wasn't temperature ratings, and it definitely was chips going into satellites. This was part of an internship at a place (I was in the "normal IC chip" testing zone, though). I just might not be sure on the "space-rated" things being "radiation-hardened" or if it's more just "well they're gonna be more tested".

You're thinking about taking commercial parts and screening them for radiation tolerance rather than building parts from the ground up to be radiation hardened. Sometimes a vendor gets lucky and the chip has a pretty decent radiation tolerance that makes it useful for short duration missions. It's not going to last 15 years in GEO orbit but it could do well on a satellite only designed to last a couple years. It's not cheap to do radiation tolerance screening but it's way more expensive to make small batches of radiation hardened parts.

Sometimes the vendor will add a little more to the substrate that doesn't increase cost much but does provide a little bit more radiation tolerance. Other times there are certain things the customer must do like constantly rewriting registers. It's not perfect but you can save a lot of money taking an off the shelf TI part and flying it versus spending tens of thousands for something of similar performance but with a guaranteed level of radiation hardness beyond what you actually need. I've used a commercial TI ADC that works really well in a radiation environment (perhaps as long as 5 years in GEO) despite not being sold as such. We just decided to screen it to see how well it performed and based on that test data, we made the decision to fly it. I'm not sure who's idea it was but something about the design of the chip led us to believe it might perform decently. TI was not involved and was at first a little concerned when we told our sales rep we were planning to fly it.

Older chip designs use larger features that generally perform better in a radiation environment than newer designs using smaller features. An old 74-series logic chip might actually perform just fine when it comes to heavy ions but may not live as long as something like a 54-series that has a larger substrate that can absorb more gamma over time.

Another method is flying unscreened radiation hardened parts, they were built to a certain standard but you buy them without all the extra testing to save a few grand because you trust the vendor has a good process.

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

#348

Post by Manuel_D »

foxyv wrote: post #345
Manuel_D wrote: post #282

Earlier quoted context omitted.

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.

I don't think that's how it works. For all we know, in ten years, parts of the Atlantic Ocean could become uninhabitable by marine life due to radioactive plumes. Or not. The history of radioactive waste disposal is very short. Dumping further could exacerbate future problems. That's kind of why we banned it. Personally I think deep bore hole disposal in geologically inactive regions makes the most sense.

The areas around the nuclear waste disposal sites are monitored for radioactivity. Radiation drops to ambient levels very sharply. Radioactive material decays over time - it'll get strictly less radioactive as time goes on.

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

#349

Post by defrost »

pvaldes wrote: post #319
defrost wrote: post #289

Earlier quoted context omitted.

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".

Invasive cancer statistics in Japan were compiled for the Fukushima Cancer Registry database and published by the National Cancer Center Japan. If we review average annual percent change on Thyroid cancer incidence, there was a more or less stable value between 2008 and 2011. Then in 2012 there is a sudden increase of 10,8% on Fukushima, versus a 3,7% for the whole Japan in the same year [1]. Some increase is normal…

> So, something happened in 2012 that increased Thyroid cancer on Fukushima .. How would you explain that?

The obvious answer would be that radioactive iodine-131 entered the food chain and that strontium-90 also was being ingested by dairy cattle and was being concentrated (biologically magnified) in cow’s milk.

As demonstrated in Australia by Hedley Marston.

This seems unrelated to what was being discussed .. the direct attribution of deaths amoung the excavated cohort to nuclear causes.

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

#350

Post by polotics »

pfdietz wrote: post #281
polotics wrote: post #270

Earlier quoted context omitted.

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.

Why either-or? it's: (1) a lot of sobriety (2) any and all available technology with a well understood and well modelled risk/reward impact/scale plan

Also note that you seem to mean new-renewables (wind and solar) when you write "renewables". At this point and for a long time the large-scale and frequent renewables are hydropower and biomass, that are renewable, but are not new.

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