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Century-old stone “tsunami stones” dot Japan's coastline (2015)

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Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#51

Post by __turbobrew__ »

m4rtink wrote: post #49
__turbobrew__ wrote: post #45

Earlier quoted context omitted.

It seems like you should build a water reservoir at a higher elevation than the core and then apply a similar principle where valves regulate the water stream, but if the valves lose power they fail open. The reservoir can be built so that there is always enough water to cool the core. For light water reactors this basically just amounts to a large pool up a nearby hill or in a water tower.

That is easier said than done - modern reactors are in the 1000 MW+ electrical power range, which means about 3x as much heat needs to be generated to get this much electricity - say 3000 MW. Even when you correctly shut down the chain reaction in the reactor (which correctly happened in the affected Fukushima powerplant) a significant amount of heat will still be generated in the reactor core for days or even weeks…

Yea, it seems like you could design a cooling loop that runs just off the latent heat. Im sure somebody in reactor design has sketched it out.

Some napkin math based upon heat capacity of water and assuming a 20 degree celsius input and 80 degree celsius output and 30MW heat results in about 120 liters per second of water flow needed. That is about 10 million liters of water per day, or about 4 olympic sized swimming pools. I don’t know how long you need to keep cooling for, but 10 million liters of water per day seems not insane and within the realm of possibility.

If you allow the water to turn into superheated steam you can extract much larger amounts of heat off the reactor as well.

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#53

Post by marcosdumay »

sparrish wrote: post #50
imchillyb wrote: post #27

Earlier quoted context omitted.

With radiation half lives what they are, our society should be brainstorming how to segregate and mark nuclear waste storage areas. All areas that store radioactive waste. Without clear warnings and boundaries humanity is just waiting for a catastrophe. A tiny sign and words don’t count.

They've already been working on that. https://www.ans.org/news/article-416/the-art-of-the-10000yea...

And I can't find the on Youtube the music for the glowing cats proposal, but if somebody can, it's highly recommended.

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#54

Post by bamboozled »

numpad0 wrote: post #42
teleforce wrote: post #11

Fun facts, Fukushima Daiichi Nuclear Power Plant was built beyond the warning limit of the tsunami stones. If those people that setup the tsunami stones are still alive during the incident they will have a kahuna of "I told you" moment.

The reactors were also largely fine except for grid connections and the hurricane-resistant backup generator in the basement. It was told ad nauseum at the time that there could have been couples of those on the roofs and the reactor could have just survived.

Imagine how much cheaper a few pumps on the roof would've been :)

Similar to mitigating climate change effects 30 years ago. Now it's way too late.

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#55

Post by Frieren »

542354234235 wrote: post #24
teleforce wrote: post #11

Fun facts, Fukushima Daiichi Nuclear Power Plant was built beyond the warning limit of the tsunami stones. If those people that setup the tsunami stones are still alive during the incident they will have a kahuna of "I told you" moment.

>Onagawa was… 60 kilometers closer than Fukushima Daiichi [to the epicenter] and the difference in seismic intensity at the two plants was negligible. Furthermore, the tsunami was bigger at Onagawa, reaching a height of 14.3 meters, compared with 13.1 meters at Fukushima Daiichi. The difference in outcomes at the two plants reveals the root cause of Fukushima Daiichi’s failures: the utility’s corporate “safety cultur…

This is why so many people are against nuclear. It may be theoretically possible to create safe nuclear plants, but capitalism is badly equipped to create them.

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#56

Post by amateurCoder5 »

marcosdumay wrote: post #53
sparrish wrote: post #50

Earlier quoted context omitted.

They've already been working on that. https://www.ans.org/news/article-416/the-art-of-the-10000yea...

And I can't find the on Youtube the music for the glowing cats proposal, but if somebody can, it's highly recommended.

Is it this one?

https://m.youtube.com/watch?v=amn3kn0XPLQ

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#57

Post by akimbostrawman »

Frieren wrote: post #55
542354234235 wrote: post #24

Earlier quoted context omitted.

>Onagawa was… 60 kilometers closer than Fukushima Daiichi [to the epicenter] and the difference in seismic intensity at the two plants was negligible. Furthermore, the tsunami was bigger at Onagawa, reaching a height of 14.3 meters, compared with 13.1 meters at Fukushima Daiichi. The difference in outcomes at the two plants reveals the root cause of Fukushima Daiichi’s failures: the utility’s corporate “safety cultur…

This is why so many people are against nuclear. It may be theoretically possible to create safe nuclear plants, but capitalism is badly equipped to create them.

I can't tell if this is a tongue in cheek joke or just blatant ignorance. The biggest in size and death nuclear powerplant disaster was Chernobyl under communism and it wasn't there first or last.

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#58

Post by shazbotter »

akimbostrawman wrote: post #57
Frieren wrote: post #55

Earlier quoted context omitted.

This is why so many people are against nuclear. It may be theoretically possible to create safe nuclear plants, but capitalism is badly equipped to create them.

I can't tell if this is a tongue in cheek joke or just blatant ignorance. The biggest in size and death nuclear powerplant disaster was Chernobyl under communism and it wasn't there first or last.

Just because authoritarian communism is also not equipped to build nuclear reactors does not mean capitalism is.

If A, then B does not imply "B, therefore A". This is called "affirming the consequent".

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#59

Post by shazbotter »

baobabKoodaa wrote: post #44
jonplackett wrote: post #22

Earlier quoted context omitted.

Well obviously they mean below

Not obvious to me

They famously got inundated with tsunami water. It's pretty reasonable to assume they were below the line of tsunami high water marks.

Re: Century-old stone “tsunami stones” dot Japan's coastline (2015)

#60

Post by veidr »

Frieren wrote: post #55
542354234235 wrote: post #24

Earlier quoted context omitted.

>Onagawa was… 60 kilometers closer than Fukushima Daiichi [to the epicenter] and the difference in seismic intensity at the two plants was negligible. Furthermore, the tsunami was bigger at Onagawa, reaching a height of 14.3 meters, compared with 13.1 meters at Fukushima Daiichi. The difference in outcomes at the two plants reveals the root cause of Fukushima Daiichi’s failures: the utility’s corporate “safety cultur…

This is why so many people are against nuclear. It may be theoretically possible to create safe nuclear plants, but capitalism is badly equipped to create them.

Maybe you mean democratic societies are badly equipped to regulate capitalist economies? There are zero successful capitalist economies that lack powerful governmental regulatory control.

Fukushima 1F was a failure of governmental regulation.

It's really important to understand that, because otherwise you inescapably frame the argument wrongly. Capitalism isn't the problem, regulatory weakness is the problem. No capitalist society can survive lack of effective regulation.

(Fukushima was bad, and an example of regulatory failure, but Japan's overall effective regulatory influence over its corporations — and similarly, its mafia — is the secret sauce that has made it an economic overperformer. China can also do that — because it is a brutal dictatorship. America can't do that — and things aren't looking good. UK retains the power to do it, but it's Keystone Kops. EU can't do it, either, for reasons I can't understand at distance.

But creating safe nuclear power plants is fundamentally the same problem as creating safe elevators. In a capitalist society, it's 100% about regulatory power and competence, and nothing else.

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