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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

#131

Post by chickenbig »

fsh wrote: post #10
Filligree wrote: post #7

Earlier quoted context omitted.

On the other hand, the existence of coal power proves that releasing small amounts of radiation is fine, really. So we should be able to build a lot more nuclear power plants; it would take a lot of accidents like these to match the releases from coal.

The explosion of Chernobyl released a few thousand PBq of activity. Coal contains a few tens to a few hundreds of Bq/kg. You would have to burn something like 50 times the world coal reserves (and make sure not to use any exhaust filters) in order to match the radiation release of Chernobyl.

> Coal contains a few tens to a few hundreds of Bq/kg

Presumably these are from very long-lived isotopes, so will continue to emit at this rate for the forseeable future.

In contrast, the fission products (from Chernobyl) tend to have short half lives of the order of a few days, giving a short burst of radiation. Caesium 137 looks to be the most troublesome isotope in the long term (with a half life of 30 years). https://en.wikipedia.org/wiki/Chernobyl_disaster#Relative_is...

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

#133

Post by ludwigschubert »

locallost wrote: post #44
TheGamerUncle wrote: post #41

Earlier quoted context omitted.

ok but lol you are still obviously denying and acting blind to the fact that for many many years, that neither we will nor our lungs will get back, coal had to be ramped up and overused in Germany, Nuclear is safe and effective and until we actually solve the battery problem most of the world should switch to nuclear if we want to survive, Yale has tried to fit the numbers on many occasions but not even them can disa…

> ok but lol you are still obviously denying and acting blind to the fact that for many many years, that neither we will nor our lungs will get back, coal had to be ramped up and overused in Germany This simply isn't true. Coal use for electricity has been declining consistently in Germany and especially since the first shutdowns of nuclear plants (cca 2011). And the replacement was not natural gas as in e.g. the US.

Here’s a chart of Germany’s energy mix over the last 30 years:

https://ourworldindata.org/grapher/share-elec-by-source?time...

Looks like coal usage for electricity production indeed only went up for ~3 years around 2011, probably we can consider that a mere blip within the downward trend.

Wind and solar indeed seem to pick up what nuclear used to bring to the energy mix. Gas usage is only slightly up over 30 years, which doesn’t look like it’s directly substituting nuclear — but surely it could have gone down had nuclear be kept around?

(Personally, I wish politics would have pushed harder against coal and simply ignored nuclear for a couple more decades. But political feasibility is important ofc, and I don’t know how hard of a sell that would have been in 2010.)

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

#134

Post by chickenbig »

pfdietz wrote: post #14
elzbardico wrote: post #12

Earlier quoted context omitted.

The fact that their system cost is prohibitive in the real world? The fact that we don’t fucking have the slightest idea of how to deal with recycling that stuff on their EOL? Or would be the fact that mining cobalt and lithium in the required quantities to indulge on the fantasy of a solar/wind based grid would poison an inordinate portion of our environment? Or would it be the fact that every single fucking country…

You provide excellent examples of the bogosity of the arguments. Let me demolish them in turn. 1) System cost Sure, it's high. That's because we spend huge amounts of money on energy. ANY system to replace fossil fuels will be expensive, in the trillions of dollars. But if this is an argument against renewables, it's an even bigger argument against nuclear. Because nuclear is much more expensive than renewables. 2) R…

> 1) System cost

> But if this is an argument against renewables, it's an even bigger argument against nuclear. Because nuclear is much more expensive than renewables.

I agree that the nuclear power stations are more expensive per kW of generation capacity. But that does not mean that the overall system must be more expensive (fallacy of composition?). It would depend on the quality of the intermittent resources, their location, demand profiles, cost to build, cost of transmission and storage and so on.

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

#135

Post by chickenbig »

7952 wrote: post #63
slt2021 wrote: post #51

Earlier quoted context omitted.

nuclear fuel: nuclear rods can last about 3-7 years, lets say 5 on avg. 150 rods per 1 GW reactor. so its like one or two rail cars of fuel - extremely compact footprint. how calculate yourself how much fossil fuel you need to power 1 GW power plant for half a decade, and how much CO2 emissions will you generate? How many rail cars of coal Germany will need to generate 1 GW 24/7/365 for 5 years reliably ? it is just…

So for nuclear power to be successful you just have to change human nature and politics to secure long term investment. And do so in countries that cannot even figure out how to properly fund education.

> you just have to change human nature and politics to secure long term investment

Perhaps it will take generational change (and stopping the propagation of anti-nuclear tropes). Perhaps it will take societal selection (where those who invest will out-compete the others).

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

#136

Post by Kon5ole »

pyrale wrote: post #23
Kon5ole wrote: post #21

Earlier quoted context omitted.

Once you decide to run nuclear power in a country you have centuries of unavoidable costs no matter what the next government, or next ten generations of citizens decide to do. This is a unique cost consideration for nuclear power, which IMO is rarely considered by the proponents.

Negative industrial byproducts creating costs for future generations is an unique challenge? Have you heard of climate change?

Any one power plant has no measurable effect on global climate. (All fossil power plants combined worldwide have about the same emissions as all cars; about 1/6).

So, if your fathers started coal plants, you close them, stop paying for them and can forget about them. this is not at all the case if your fathers started nuclear plants, not only do you have to pay, your children have to pay, all their lives, and all your grandchildren, and so on.

What bugs me is the tendency of proponents to pretend that the decision is no biggie. It is a biggie. At least understand that, then we can have a rational discussion about it!

Energy storage solutions and infrastructure for generating synthesized fuels (hydrogen and others) will require investments, but those investments will be a gift to the future. We will bear the burden of building the infrastructure now, but future generations will benefit from what we have built.

Nuclear is the opposite, we get the benefits and the future gets the burden.

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

#137

Post by virtue3 »

legulere wrote: post #67
JumpCrisscross wrote: post #29

Earlier quoted context omitted.

> 61.5% of Germany's electricity comes from renewable sources Now. For years they switched to coal. Even today, Germany falls to the siren songs of the gas lobby, who promise a €1.5tn investment into gas infrastructure will be happily written off for the sake of the planet.

Nuclear was replaced by renewables, not by coal: https://commons.wikimedia.org/wiki/File:Energiemix_Deutschla... https://commons.wikimedia.org/wiki/File:Electricity_generati... A point you certainly can argue about, is that coal should have been replaced by renewables before nuclear, but that discussion is over now. For gas use electricity production is just a minor use. Most gas is consumed by industry and for heati…

Here are some key events in Germany's nuclear phase-out: 1998 A coalition government includes the phasing out of nuclear power in its policy

(this was later un-done in 2009 and then redone in 2011 which is the cause of confusion).

IE. Germany got INCREDIBLY lucky that China went hard into renewables and dropped the price of them dramatically. Because they did basically replace or plan to replace all the nuclear plants with coal plants.

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

#138

Post by pyrale »

Kon5ole wrote: post #136
pyrale wrote: post #23

Earlier quoted context omitted.

Negative industrial byproducts creating costs for future generations is an unique challenge? Have you heard of climate change?

Any one power plant has no measurable effect on global climate. (All fossil power plants combined worldwide have about the same emissions as all cars; about 1/6). So, if your fathers started coal plants, you close them, stop paying for them and can forget about them. this is not at all the case if your fathers started nuclear plants, not only do you have to pay, your children have to pay, all their lives, and all you…

So basically you’re so caught up in this infighting between two carbon neutral energies that you’d rather spread disinformation about climate change and the negative effects of coal…

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

#139

Post by defrost »

natmaka wrote: post #113
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…

Deaths (nuclear accident): 1 confirmed from radiation (lung cancer, 4 years later), and 2,202 from evacuation. Source: https://en.wikipedia.org/wiki/Fukushima_Daiichi_nuclear_disa... Long-term effects on health are disputed: http://csrp.jp/wp-content/uploads/2014/09/2013-UNSCEAR-Repor... http://www.fukushima-disaster.de/fileadmin/user_upload/pdf/e... https://apjjf.org/thierry-ribault/4761/article The nuclear accident…

> 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 2,202 disaster-related deaths in Fukushima\*, according to the government’s Reconstruction Agency, from evacuation stress, interruption to medical care and suicide; so far, there has not been a single case of cancer linked to radiation from the plant.

    That is prompting a shocking reassessment among some scholars: that the evacuation was an error. The human cost would have been far smaller had people stayed where they were, they argue. The wider death toll from the quake was 15,895, according to the National Police Agency.

     Of the disaster-related deaths, 1,984 were people over the age of 65.
~ https://www.ft.com/content/000f864e-22ba-11e8-add1-0e8958b18...

\* technically not "in Fukushima" but any deaths over the following seven years in the group evacuated from Fukushima.

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

#140

Post by Kon5ole »

bell-cot wrote: post #99
wkat4242 wrote: post #55

Earlier quoted context omitted.

Barrels don't last when filled with nuclear material. The radiation embrittles the materials over time, they wouldn't last 100 years. And then all that crap will be released into the ocean and swerve all over the world.

Assume that the folks building the barrels know about the embrittlement, and have both a decent budget and some experienced engineers to mitigate the problem. Also note my phrase "bury them". Radwaste is not some magical Sealed Evil in a Can. If bound in compounds with substantially higher density that the ocean sediments, and emplaced a few tens of meters below the sea floor, then gravity will quite strongly discour…

Four decades of studies by experienced engineers and a very decent budget to figure out how to store US nuclear waste has resulted in 0 solutions so far. I think we can safely assume that dumping it at sea is not an option.
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