Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Fukushima Reactor: TEPCO robot aims to extract nuclear fuel

spectrum.ieee.org

Post reply on HN
Print view View original

291–300 of 357 posts

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

#291

Post by natmaka »

LargoLasskhyfv wrote: post #229
natmaka wrote: post #210

Earlier quoted context omitted.

Please source.

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 industrially obtain electricity from renewable sources (no major accident similar to a nuclear's one, nor such dangerous waste).

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

#292

Post by natmaka »

slt2021 wrote: post #243
natmaka wrote: post #189

Earlier quoted context omitted.

It's not about energy density but availability. If a nation cannot buy uranium (scarce resources, embargo...) it loses at least temporarily its nuclear infrastructure (and gasps for energy). This is not a real concern for renewables. > Nuclear is capturing strong and weak forces Other (way more practical and determinant) parameters are less enticing. For example: it 'burns' uranium and produces dangerous waste.

>>If a nation cannot buy uranium (scarce resources, embargo...) not an issue at all, Canada, Australia, Kazakhstan, bunch of other nations mine and sell uranium. Whenever there are big mountain ranges, there is uranium. and it is cheap as a commodity

Current uranium reserves are sufficient, under current obtention conditions, for slightly over 130 years of supply.

Nuclear now produces, worldwide, less than 10% of electricity (which is less than 2.2% of total final energy).

Double the reactor fleet and each new one will only produce under current conditions for 60 years (in other words it will probably be quite difficult to finance).

Canada and Australia pertain to the Anglosphere, therefore if nuclear enjoys a 'Renaissance' in the US they will provide uranium to their friends first, and will not provide it to any nation not aligned with the Anglosphere. For quite a bunch of nation Canada and Australia aren't dependable providers.

Kazakhstan can be subdued by Russia (yeah, I know, their current stance is apparently defiant, however recent history is quite clear: https://en.wikipedia.org/wiki/Kazakhstan%E2%80%93Russia_rela... ) or even China. Uzbekistan, also extracting uranium, stands in similar shoes. Who wants to have to beg Russia for uranium?

Read on: https://www.reuters.com/business/energy/exclusive-us-utiliti...

https://www.nytimes.com/2023/03/10/business/economy/russia-n...

https://www.hydesmith.senate.gov/hyde-smith-questions-us-rel...

> bunch of other nations mine and sell uranium

Not really. Niger, Namibia? China and Russia are more and more in control there.

> Whenever there are big mountain ranges, there is uranium. and it is cheap as a commodity

Not at all. Please source. In many places obtaining it is very difficult due to local conditions, ore grade...

During the 'uranium bubble' (around 2007) prospection hugely intensified and raised a mere 15% new known and inferred reserves ( https://en.wikipedia.org/wiki/Uranium_bubble_of_2007#Impact ). Who wants to bet billions on this?

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

#293

Post by natmaka »

slt2021 wrote: post #244
natmaka wrote: post #217

Earlier quoted context omitted.

> stockpiled Doing so may trigger a market tension. France reprocesses only part of its fuel, and only 1 time. > the problem will be the same Uh? An existing fleet of reactors is moot without uranium. An existing fleet of renewables just works (it only needs wind, sun, geothermal activity...)

Uranium supply is not an issue at all, given that plenty of nations sell it, it is not rare mineral and can be found in abundance. and you need to replenish uranium fuel like once in 5 years - so this is not an issue at all for nuclear energy

> Uranium supply is not an issue

I disagree: https://news.ycombinator.com/item?id=41783584

> you need to replenish uranium fuel like once in 5 years

At best. Then, if you cannot obtain uranium, your reactor is just a pile of hot waste.

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

#294

Post by natmaka »

Moldoteck wrote: post #220
natmaka wrote: post #217

Earlier quoted context omitted.

> stockpiled Doing so may trigger a market tension. France reprocesses only part of its fuel, and only 1 time. > the problem will be the same Uh? An existing fleet of reactors is moot without uranium. An existing fleet of renewables just works (it only needs wind, sun, geothermal activity...)

you need to gradually replace renewables, especially for a grid that was gradually deployed. You still can stockpile nuclear, France does have several years worth of fuel for such emergencies. France reprocesses only part of the fuel, is expanding Orano facility, but why is this relevant? They do it and they get additional un-enriched uranium stockpile. WTH dude? Are you just throwing random antinuclear statements ar…

Most materials used by renewables are eternally (at human scale) reusable. In France recycling 95% of the sheer mass of a wind turbine is now mandatory ( https://www.lemoniteur.fr/article/demantelement-des-eolienne... )

> France does have several years worth of fuel

Indeed, 'le stock stratégique', about 9 years at best (counting the average amount of uranium already present in reactors). 9 years at best for an overall of your gridpower production system... good luck with this!

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

#295

Post by natmaka »

Moldoteck wrote: post #222
natmaka wrote: post #218

Earlier quoted context omitted.

> unit 4 proved there's positive learning curve Unit 4 proved that work units in a given project, sharing the same lapse of time and space, can benefit. Extrapolating it to a whole set of projects is another matter (see the referenced study). > a continental scale grid Already exists and is continuously extended: https://en.wikipedia.org/wiki/European_Network_of_Transmissi... > dunkelflaute Its real impact (surface,…

Yeah, vastly overstated... at this point you're not serious dude. I'm also very aware of european grid, but I guess you didn't read the part that you still need huge overcapacity

I cannot see any counter-argument in your answer.

> huge overcapacity

You didn't source this. This vastly depends on many parameters. Moreover as renewables machines are cheap, recyclable, and can be installed in unused places (or even protect them, as offshore wind does for oceans) you have yet to show which challenge this 'huge overcapacity' stems.

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

#296

Post by natmaka »

vlovich123 wrote: post #277
natmaka wrote: post #174

Earlier quoted context omitted.

> need for batteries They are needed for transportation, whatever the way we produce electricity (even with nuclear). > renewables can’t be used in various industrial processes Why? There is no difference between nuclear-produced electricy and renewable-produced (or battery-stored)-electricy. > Hopefully we get fusion soon Does some optimistic scientist hope to enjoy an industrial prototype before 2050?

In the renewables case they’re needed for transportation AND grid. The dream that car batteries are used as grid storage afaict remains a dream with no forward movement on that front.

> In the renewables case they’re needed for transportation AND grid.

Indeed. So? There are more and more vehicles, and the average amount of electricity they store (reflected by their autonomy) grows. One of the reasons is well-known: https://ourworldindata.org/battery-price-decline

> no forward movement

This isn't true, many experiments are running ( https://en.wikipedia.org/wiki/Vehicle-to-grid#Research )

Even EDF, France's leader of the nuclear industry, field-experiments it: https://www.edf.fr/entreprises/transition-energetique/mobili...

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

#297

Post by natmaka »

Dalewyn wrote: post #248
natmaka wrote: post #169

Earlier quoted context omitted.

Naoto Kan was an advocate of nuclear energy, changed his mind after Fukushima, and the industry now tries hard to use him as a scapegoat. Don't worry, experts are perfectly able to maintain a high level of safety (nope), then to assess correctly during an accident (nope: https://www.scientificamerican.com/article/nuclear-power-ody... ), and also to manage the aftermath (nope... https://www.scientificamerican.com/arti…

Congratulations, you're armpits-deep in the Japanese political propaganda machine. PM Naoto Kan infamously declared "I know nuclear!" in unilaterally ordering TEPCO around during the crisis and ultimately denying their request to scuttle the reactors. Nevermind that TEPCO had the finest nuclear engineers Japan could muster at that moment. For his valiant achievement of causing a nuclear meltdown and turning back the…

> ultimately denying their request to scuttle the reactors

A solid source detailing the story would be useful.

TEPCO ignored his order to stop pumping in order to avoid re-criticality, and Kan soon accepted TEPCO views on the matter: This seems sourced to me (no mention of scuttling anything): https://en.wikipedia.org/wiki/Naoto_Kan#Fukushima_nuclear_ac...

> was rewarded with merely the loss of

I don't think so. Japan was, then, in a political turmoil with 4 prime ministers from September 2006 to June 2010 (when his mandate began): https://en.wikipedia.org/wiki/List_of_prime_ministers_of_Jap...

He passed a bill to promote the use renewable energy. This is sufficient, even for this ex nuclear enthusiast, to be blacklisted and villified.

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

#298

Post by natmaka »

Dalewyn wrote: post #251
natmaka wrote: post #120

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.

Refusing to understand that everyone (politician or not) can fail and that if we now can replace something dangerous in case of failure (nuclear) by something new which isn't (renewables), we should do so... is the error in logic I am talking about.

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

#299

Post by natmaka »

lupusreal wrote: post #219
natmaka wrote: post #164

Earlier quoted context omitted.

> 0.45% of the nuclear waste Do you mean that the Fukushima nuclear accident dumped locally in a few days 0.45% of all dumped nuclear waste during the last ~80 years?"? If so it seems non-negligible to me. > 20 years earlier (nothing on tectonic timescales) this wouldn't be up to much discussion Not sure about this. Maybe ~50 years ago, and even so the accident at Three Mile Island (1979) didn't pollute much but trig…

"Triggered quite a lot of discussions" is an ultra-low bar. Lots of hysterical bullshit triggers a lot of discussion. Aliens, puzzagate, etc. TMI was an expensive mistake but the public wasn't at risk.

... thanks to sheer luck as, AFAIK, no-one knows exactly why the reactor didn't completely melt, threatening the vessel and therefore containment.

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

#300

Post by vlovich123 »

natmaka wrote: post #296
vlovich123 wrote: post #277

Earlier quoted context omitted.

In the renewables case they’re needed for transportation AND grid. The dream that car batteries are used as grid storage afaict remains a dream with no forward movement on that front.

> In the renewables case they’re needed for transportation AND grid. Indeed. So? There are more and more vehicles, and the average amount of electricity they store (reflected by their autonomy) grows. One of the reasons is well-known: https://ourworldindata.org/battery-price-decline > no forward movement This isn't true, many experiments are running ( https://en.wikipedia.org/wiki/Vehicle-to-grid#Research ) Even EDF,…

The drawbacks section is pretty damming that this is unlikely to work:

> JB Straubel, then chief technology officer of Tesla Inc, discounted V2G, claiming that battery wear outweighs economic benefit.[87] A 2017 study found decreasing capacity,[88][89] and a 2012 hybrid-EV study found minor benefit.[90] A 2015 study[91] found that economic analyses favorable to V2G failed to include many of the less obvious costs associated with its implementation. When these less obvious costs were included, the study reported that V2G was an economically inefficient solution.

Post reply on HN