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Comment by Yaggo | Hacker News Reader

When the said plant project started over 10 years ago, I was an opponent of nuclear power, participating in demonstrations etc. Nowadays I'm really thankful for the new plant, as every non-fossil energy source is absolutely crucial, not to mention my electricity bill. Actually nuclear has the lowest carbon footprint, and a big advantage of being able to deliver very stable power output. The challenge with waste storage and other risks are real of course, but we just have to to accept them in the current situation of global warming.

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Started over 10 years ago is an understatement. It was supposed to be finished over 10 years ago. First the Berlin airport, now this and James Webb Space Telescope: are we really just going to finish our collective homeworks?

Yeah, the final permission for the project was granted in 2002, almost 20 years ago. So I was also 20 years younger. You know, after certain age everything feels "just few years" ago.

There was also a generation gap between the earlier builders of nuclear plants and now these. Lots of knowhow was lost as we paused building nuclear for a long time. I hope we can now keep on building new plants, riding on the wave of experience from the recent projects and keeping it alive to make future builds cheaper and faster.

The worst part is that some of this know-how might've been the stuff that makes the plants safe, an accident at a newly built plant due to this would be a death-knell to the industry and our hopes of clean energy.

Also in this theme, even if material science has advanced I'm a bit curious as if it has really advanced enough that people trying to promote building molten salt breeders over and over again (that's the ones that are highly corrosive iirc? if not insert the ones with practical problems).

I'm not very worried about the safety aspect, as the safety features are probably among the most explicit parts of the design. These are carefully designed, modeled and simulated and are also the focus of the regulators. Moreover, there hardly has been a lot of room for commercial nuclear designers to the software development-like approach of trying, failing and trying again. Maybe the early experimental and weapon related reactor designers worked like that at some point? These days safety is the first priority for designers and operators alike. One example illustrating the thinking is the EPR core catcher: while the active safety features in EPR mean it's possibly the safest reactor type ever built, there are provisions to minimize enviromental release of radioactive materials in the case of catastrophic failure.

I think such design things overall is what's needed to make things safe for the environment all around, but if there was stuff that was known to designers 40-50 years ago that wasn't properly logged "and lived within the walls" then we might encounter minor failures (that in worst case could lead to major ones).

Reading about many of the early accidents in military and early nuclear industry, I'm not too sure that there wasn't quite a bit of "trying and failing" going on back then, and while that culture is not up to the NASA standards we see in space flights we've also seen how some of their contractors got slower and slower to the point where they lost the ability to finish things in time (and as time drags on the repeating of mistakes will come up again).

Estimations are really hard. I don't know about you but I consistently under evaluate every piece of work...

It's rarely simple/honest misestimations with large government contracts though.

There is just too much money to be made for the corrupt people to stay away.

The honest and good offers are rarely taken, because they've realistic estimations - the dishonest one's only care about getting the contract, not finishing it... So they'll make the much better offer. And once work starts, the corruption keeps spreading. Everyone on every layer knows how unlikely their charges are going to be contested, so everyone just charges more for the same work, siphoning money from the project.

I'd consider that a cultural issue, because people at large have really started to only think about themselves and no longer identify with their work ethic. Which is understandable because the employers generally treat their employees like disposable tools.

I don't think there is any straightforward or easy solution, and it can get much much worse too. Just look at china's production issues for inland products, esp. food and consumable products.

This project wasn't government project though, but TVO's.

If you accurately estaimted the pain and time required to complete something, you'd never get started.

Hofstadter's Law: It always takes longer than you expect, even when you take into account Hofstadter's Law.

Anything is small beans compared to Basílica de la Sagrada Família.

Building started July 2005.

> The challenge with waste storage and other risks are real of course

But the “challenge” with waste storage is a big lie.

The French have all the waste ever generated by their nuclear program sitting under the floor of a single room. The quantities of “waste” generated by nuclear plants are not really meaningful even over long time horizons.

Also Finland has for the most part solved our nuclear waste problem.

A couple km down the road from Olkiluoto is Onkalo which is basically ready with now going through final checkups and to be put into use in 2023.

https://en.wikipedia.org/wiki/Onkalo_spent_nuclear_fuel_repo...

Yup. The risk factor there is that humans might go extinct and then aliens visit Earth in 20k years and decide to start digging.

Yeah the risks are really low. Basically you would have to dig down there for any risk. The risk simulations they did for it are hilarious to read

This is the worst case scenario they thought about

> Posiva on arvioinut ydinjätteiden pahimpia mahdollisia seurauksia. Skenaariossa ydinkanisteri syöpyisi puhki tuhannessa vuodessa lasketun sadantuhannen vuoden sijaan ja samanaikaisesti sitä ympäröivä savipuskuri katoaisi selittämättömästi. Lisäksi pohjavesi kulkisikin ylöspäin ja paikan päälle rakennettaisiin kaupunki. Ihminen, joka eläisi kehdosta hautaan saastuneimmalla neliömetrillä ja söisi vain sillä kasvanutta ruokaa ja joisi saastuneinta vettä, saisi vain kolminkertaisen säteilyannoksen Tampereen Pispalassa nyt asuviin ihmisiin nähden.

Rough translation

> Posivat has estimated the worst case scenarios. In the case the vessels would corrode in 1000 years instead of the calculated 100000 years and the clay barrier would "disappear" (nobody knows how it would do that) and the ground water would move upwards (it moves down in that area) and someone built a city above it and ate from crops grown on the worst possible radiated land they would get 3x the lifetime radiation does of someone living in Piispala, Tampere

(the stuff in quotes is my additions)

Hahaha, hilarious indeed!

> [..] all the waste ever generated [...]

All the waste?

https://www.nrc.gov/waste/llw-disposal/licensing/statistics....

"Approximately 1.01 million cubic feet and 40 thousand curies of low-level radioactive waste were disposed of in 2020"

Low-level radioactive waste is not really big a problem. It does not pose any significant risk to anyone or anything.

High-level waste is the problem.

> Low-level radioactive waste is not really big a problem. It does not pose any significant risk to anyone or anything

At some abstract factual level that claim may not be [that] wrong, but I'm not convinced that statements such as that help promote the nuclear cause.

Nothing abstract about it. Low-level waste is really not dangerous.

That's not necessarily the case. In Europe after Chernobyl, radioactivity accumulated in cow's milk via grass contaminated with strontium. Children were particularly at risk because strontium is absorbed into growing bones in a similar manner to calcium. Even a low-level of radioactivity in that context can be harmful.

https://hidex.com/ebooks/liquid-scintillation-measuring-proc...

https://www.journalofdairyscience.org/article/S0022-0302(96)....

I (believe I) appreciate the physics of that claim ... but why do we bother collecting it and handling it separately?

There are towns around Utah and elsewhere in the US, with very high cancer rates from open-air uranium/vanadium/etc mining, and working in the mines.

I've visited this place and they have like historical monuments dedicated to the handling of the health issues: https://en.wikipedia.org/wiki/Monticello,_Utah#Uranium_minin...

And luckily the level of radioactivity is inversely proportional with the half-life. The hotter it burn, the faster it decay.

>All the waste?

Probably not the most boring kind of waste.

> "Approximately 1.01 million cubic feet and 40 thousand curies of low-level radioactive waste were disposed of in 2020"

It’s worth noting that even a million cubic feet isn’t a big quantity, this is something one guy with an excavator could feasibly bury. (Not that we should actually pursue the guy-with-excavator disposal strategy)

It's 28317 cubic metres or 500 residential swimming pools, 4 by 7 by 2 metres. By contrast 250000 cubic metres of concrete went into OL3[1]. This is also low level waste such as Fukushima rubble. For reference the UK has LLW in storage amounting to 14700 cubic metres or 17800 tonnes by mass, with an activity of 11 terabecquerels.

These are the estimates for decomissioning of all the Olkiluoto reactors[2]:

"The amount of decommissioning waste is around 32 000 m3, generated from Olkiluoto 1 and 2 mainly during 2068-2076. The amount of Olkiluoto 3 decommissioning waste is estimated to be around 11000 m3 before packing and generated during 2079-2085. Additionally there will be approximately 2000 m3 of waste from the spent fuel interim storage decommissioning to be generated around 2100."

  1. https://www.tvo.fi/uploads/File/2009/OL3_Basic_Facts_2009.pdf
  2. https://ec.europa.eu/energy/sites/ener/files/fi_2nd_nr.pdf

Those are numbers for the waste from bomb making, not power generation.

Those two have been linked together ever since the discovery of the chain reactions. The US nuclear weapons are managed by the Department of Energy..

It's not even an actual "waste". Given a proper nuclear cycle and a proper diversity of reactors, you can both extract precious isotopes and reuse "waste" as fuel for another kind of reactor.

AFAIK, Russia, for example, had got extremely good at cycling nuclear materials. I assume it is due to the fact that after Chernobyl they were actually forced to invest in nuclear energy due to safety reasons, rather then abandon it.

Uh, there's plenty of spent fuel components that aren't fissile. It's not a perpetual motion machine. So to say that it's not "actual waste" is rather unhelpful.

A breeder reactor can extract fifty to a hundred times more energy from nuclear fuel than the reactors we're currently using. What's left after the breeder is through has relatively short half life and needn't be stored "forever".

All that a breeder does is that it consumes U238 in addition to U235 (in much higher quantities than a non-breeder, of course). I don't quite see how this changes the amount of actual waste per unit of energy generated. Which means that a breeder will decrease the amount of uranium that you need to mine, but that's about it. Your "soup" of fission products will be very similar between Pu239 and U235 fission, so what you're saying about "what's left [having] relatively short half life" works for current non-breeder reactors as well. And activation products I imagine are almost the same. (Why wouldn't they be?)

No. Read about "burner" reactors: https://en.wikipedia.org/wiki/Breeder_reactor#Waste_reductio...

You're talking about fast-neutron reactors, not about breeder reactors. Fast-neutron reactors can split certain actinides that thermal reactors won't split, but a fast-neutron reactor doesn't have to be a breeder and a breeder doesn't have to be a fast-neutron reactor. In fact, when it comes to fast-neutron reactors, a burner (which consumers fissionable actinides you put in it) is the exact opposite of breeder (which produces more fissionable actinides than you put in it initially). Not quite sure how you mixed that up.

AFAIK most fast-neutron reactors can be used as both burners and breeders depending on loaded blanket. The same neutron flux can be used to split actinides and transform U238. The planned BREST reactor is a good example here: https://en.wikipedia.org/wiki/BREST_(reactor)

But you can't end up simultaneously with less and more actinides at the same time. That alone is mathematical impossibility.

What? Different blankets simply produce different results. Load blanket with mostly U238, irradiate it with fast neutron flux for a bit, and finally radio-chemically process the result to extract useful fission elements for new fuel rods to be used in thermal-neutron reactors. Load blanket with waste (stuff which you got after removing Uranium and Plutonium from spent fuel rods) and keep under fast neutron flux for some time and in addition to a bit of energy you will get radioactive, but relatively short-lived waste since almost all actinides will be destroyed.

Then you're reconfiguring a breeder into a burner. You don't have both at the same time.

But I have to say that the part where you concentrate a substantial mass of an unholy mix of medium-lived actinides to be burned into a fairly large structure seems kind of scary. I'm not sure I'd like to work in that part of a nuclear fuel processing plant. Fortunately it's almost certainly an academic question because the probability of this coming into fruition is very low nowadays.

>Then you're reconfiguring a breeder into a burner. You don't have both at the same time.

My point was what the same fast reactor can be used as both breeder and burner without specifying "at the same time". And I am pretty sure (though not 100% confident) that you can mix both breeder and burner rods, thus changing breeder/burner ratio at will.

>the part where you concentrate a substantial mass of an unholy mix of medium-lived actinides to be burned into a fairly large structure seems kind of scary

Yeah, fuel and waste handling is probably the most difficult part of a breeder/burner system, not the reactor itself.

No, fast neutron reactors are less poisonable, and can achieve much higher burnups even with conventional fuel.

Well, I didn't dispute any of these two. I'm just not sure how one can claim that a breeder's spent fuel "has relatively short half life" when the actinides from a breeder (such as Pu239) have medium half life and a breeder is specifically designed to produce them in substantial amounts, higher than the original load of fissile material.

The detail you’re overlooking is that it stays active for thousands of years, so even a small volume will end up being very costly.

And other countries have much higher volume of waste stored, how about 40000m3? https://en.m.wikipedia.org/wiki/Morsleben_radioactive_waste_...

The most radioactive fraction has relatively short lifetimes. (There is only so much energy that can be radiated out.) Even the Elephant's Foot in Chernobyl is much less radioactive now, mere 35 years after the accident.

The less radioactive fraction will indeed stay active for thousands of years, but its level of radiation will be closer to natural sources than to an atomic bomb.

There's a sour spot of isotopes with half-lives of 1-100 thousands years, these are still very radioactive but will not decay in any forseeable future.

How can you be so sure about that? We have like waste from max 40-50 years now sitting around and the problem is still unsolved. I doubt that civilisation can manage to manage this waste for 100'000y to come.

Because the quantities of waste are laughable https://nda.blog.gov.uk/2019/08/02/how-much-radioactive-wast...

(The HLW is what people mostly worry about)

Even in a weird scenario where we don’t start recycling our nuclear “waste”, storing 100000x the current amounts would not present a particularly huge challenge.

The really radioactive stuff (fission products) is basically gone after 300 years. The longer-lived stuff (transuranic elements: plutonium etc) could in theory be recycled and burned up in another reactor, though this probably won't happen in practice. It's not as scary as the fission products though: it's less mobile, less bioavailable, less radioactive, etc. Still definitely a hazard, but a lower grade of hazard.

The waste will be radioactive for 100000 years, but it will not be dangerous for that long. Low levels of radioactivity is not a problem. It takes a much shorter time for the waste to reach the same level of radioactivity that the original ore that we dug out of the earth had.

It's sitting around. Solid. Inert. Meanwhile there are gigatons of CO2 released to the atmosphere every year that causes an extremely acute global problem and we have no idea what to do to that either.

My post was not about CO2 (the fact that I hate that we emit way too much that I remove some via Stripe Climatr). Sitting nuclear waste still needs to be maintained for centuries to come and we still have no solition for that.

But there is little difference to maintain the current amount of waste or 100 times as much.

The challenge is a lot smaller than it is generally made out to be. Nuclear waste has a weird decay curve due to the absolute mess of isotopes it contains. That means it is insanely radioactive at first, but also decays very quickly. After a while, only the long-lived isotopes are left, but they are also not very radioactive.

We tend to conflate the two, and assume that the waste is both highly radioactive AND long-lived, but this is not the case. It is highly radioactive for a reasonable amount of time, and then low-level radioactive for a really long time.

The challenge is only how to handle it while it is incredibly radioactive, but the timescales involved are not at all impossible to deal with. Once it has cooled down, just leaving it buried is perfectly fine. There's very little long-term risk.

(Let's say, as an oversimplification, that the time of high danger is maybe two hundred years - a long time to be sure, but not unprecedented in terms of large-scale engineering projects. Around that time, the radioactivity starts dropping very sharply.)

The challenge even at low radioactivity is materials for containment. If containers are damaged by the waste, as they likely will be over long durations, than refreshing the containers is insanely complex and fraught with hazards.

And from a geopolitical perspective, given everything going on and Finland’s neighbour

It's almost as if you could benefit of thinking about second-order effects instead of following ideology blindly. Unfortunately nuanced discussion and thinking seems to be out of fashion.

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