[AtlasBarfed]

OK.

So ... WHY are there so many regulations and safety procedures? Is this political fluff? Pure overhead? I don't think so. It is inherent to the nature of a solid fuel rod reactor, the incidence (and fear) of meltdowns, and the fear of nuclear waste.

What is a nuclear meltdown. In solid fuel reactors a nuclear chain reaction is induced, so an atom of nuclear fuel splits from an incoming neutron, and in the process releases more-than-one neutron which then can trigger more fission events in nearby atoms. Of course you don't want all the fuel chain reacting in a geometrically expanding rate. That's a runaway reaction.

If intended, it can be a bomb. In a power reactor, a runaway reaction heats the solid fuel to such a degree that it melts anything around it, and gravity pulls it downward and it melts its way through ... anything. Eventually you hope the solid fuel expends enough of the fuel that it stops doing this, but by then the reactor is ruined and the national news cycle has hit.

So how does a solid fuel reactor stop runaway chain reactors? Moderator rods/systems and cooling. Perhaps you've seen some cartoon anime of an overloading reactor where the operators desperately inject rods into something. That is a moderator rod, trying to absorb and reduce the number of neutrons flying around and slow down the reaction. And there is good old cooling too.

But, like Fukushima showed, control systems are vulnerable to failure. Think you've designed enough failsafes? Nature will hit you with a bigger tsunami or a bigger hurricane or a bigger earthquake. Or.... humans over time will get lazy.

Solid fuel produces waste. As solid fuel is used, and the atoms either split in fission reactions, or absorb neutrons transmuting to other elements (some with bad half-lifes, more aggressive gamma emissions, etc). YOU CAN'T REMOVE THIS WASTE while the fuel is being used. So once enough of the solid fuel rod is used, it won't sustain a fission reaction anymore, it is then full of a ton of waste and crap.

So you have to transport it either to Yucca for long term storage, or maybe you truck it to someplace that will "reprocess it".

So solid fuel, NO MATTER WHAT, will involve active control systems and waste transport.

This is what the public is afraid of, and what nuclear meltdowns have shown can happen.

Thus every design needs to be carefully reviewed, approved, reapproved, and since there are so many actively managed safety systems with the threat of horrid meltdown, procedures and inspections and the like.

Well, what if there was a nuclear reactor design that:

1) CANNOT MELT DOWN (no disasterous runaway scenarios)

2) uses all its fuel (no waste)

So no transport of evil radioactive waste or dirty bomb material through your neighborhoods. No explosions (Chernobyl) or permanently hot cordoned off slag heaps of steel and concrete (Fukushima). No Yucca mountain.

Here's more advantages:

- scalable to small sizes, so no massive behemoth concrete towers and the like.

- doesn't even use uranium (and a rare isotope of uranium at that), it can breed fuel from thorium which is much more stable and non-radioactive.

- proliferation resistance aka can't make bombs from it (allegedly)

- possibly can "burn" nuclear waste from solid fuel reactors

It is a Molten Salt Reactor, or Liquid Fluorine Thorium Reactor. The fuel is liquid. There is a lot of stuff on the internet about it from enthusiasts. You can actively reprocess the fuel as the reactor is generating power (because you pipe it out). Because it is a breeder reactor, you can breed transuranic waste with neutrons into usable isotopes. You can extract "fission products" (the non-fissile elements resulting from atom splits or radioactive decay) from the liquid using chemical processing. In the process of "online processing" the liquid fuel, you constantly pipe the usable part back to the reactor. So the reactor uses ALL the fuel.

The liquid nature of the fuel expands and contracts with the heat of the liquid, reducing criticality. IF you get overheated, a "plug" melts that drains the liquid fuel into a cooling pan that separates the liquid into a state where it is non-critical (won't sustain a chain reaction). IF the containment reactor "sprang a leak",well, the liquid would spill into a shape that was non-critical. It can't melt down. Even if every safety system fails, it can't melt down.

The problem is a commercial design doesn't exist. At some point in the early 1970s the development was axed by the Nixon Administration (and political backstabbing if you listen to the proponents) in favor of solid fuel rod reactors.

The ENTIRE nuclear power industry is built around solid fuel. Its all they can conceive of. But as I described, solid fuel is fatally flawed from a political perspective. Large scale solid fuel reactors will never be on time and under budget in the USA.

China is actively working on LFTR/MSR/liquid fuel reactors. Coincidentally (not) there are several research reactors appearing in some US research universities and national labs. And LFTR/MSR has some real challenges in materials engineering (molten salts are hard), and of course the liquid fuel reprocessing is complicated, not as hand-wavy as I may have made it seem.

But IMO the fundamental advantages of the approach are the only known viable path to a nuclear reactor that is economical and politically palatable in the USA. A fundamentally safe practically waste-free reactor.

The you wouldn't need so many white gloves, inspectors, etc. Scalability means you can build them in a factory, and if one of 20-100 reactors fail (can't melt down, remember), well, you drain the (liquid, remember) fuel and cart it away and replace it with a new one and pipe the fuel back into the new one.

Now to emphasize THERE ISN'T A VIABLE COMMERCIAL DESIGN YET. Maybe it's impossible. And the vast majority of the nuclear industry (solid rod reprocessing, waste transport, reactor vendors) doesn't even want a liquid reactor, because they can't profit off of it. They have no interest in its development because it is a massive risk, they are desperately trying to eke a profit out of current nuclear plants, which are fundamentally noncompetitive on LCOE economics. Really, the government has to do it.

[jdkee]

"But, like Fukushima showed, control systems are vulnerable to failure."

Fukishima showed that organizational incompetence that led to backup generators being placed in the tsunami zone is a bad idea.

[Gwypaas]

There has been more near misses in the nuclear industry than tsunamis. After Fukushima about all plants in the west had to install independent core cooling because the regulators realized the risk was systemic, even though the cause was special in the case of Fukushima.

A nuclear reactor in Sweden had a severe incident in 2006 when many of the "defense in depth" layers had been accidentally removed through freak occurrences and upgrades.

https://en.wikipedia.org/wiki/Forsmark_Nuclear_Power_Plant#J...

[AtlasBarfed]

Do you think blaming "organizational incompetence" as a one-off is going to relieve constant review and regulation?

*You're arguing against the wrong point.*

Organizational incompetence is an every GREATER inevitability than a tsunami, earthquake, meteor strike, tornado, hurricane, or terrorist attack.

The point is that solid fuel reactors are currently completely fucked from an economic standpoint. They are fundamentally economically noncompetitive. They will hang on until grid storage, geothermal, or (god help us) natural gas turbine + CO2 capture replaces them as grid levelers. No, I don't think pebble bed or other approaches will work.

I love nuclear, it is so cool. I WANT a viable nuclear reactor option, that's competitive and useful. Does it HAVE to be LFTR? No, it's just the only design I see that really addresses all the semi-rational political concerns.

The nuclear lobby does itself no favors, just like you did with your immediate retort. "Death rates are low". "Nobody died from Fukushima". Those are fundamentally losing arguments politically, it will get the nuclear industry nowhere.

Now, as I said, the entire "nuclear lobby" is the "solid fuel legacy nuclear design lobby". They are riding out a loser's hand as long as they can. A switch to a radical new design might as well be the same thing as shutting down every existing nuclear plant. It's the same economic armageddon to them, so they don't care about "nuclear the idea" just "nuclear the profits".

But the dangerous thing is that all the practical nuclear engineering/knowledge that might allow a radical reactor design to succeed won't be around if the nuclear industry just clings to a slowly sinking ship. Everyone will die or retire in a generation, and then nuclear power, the IDEA, has a longer road to viability. Or it may be permanently disabled.

I don't want that. I want the nuclear industry, nuclear lobby, and American research infrastructure to WAKE UP and start really working on economically viable reactors. NOW. I mean, China isn't asleep at the switch.

But I don't see it. I see bullshit astroturfing stories like clockwork here. Which just saddens me.

[jdkee]

"Organizational incompetence is an every GREATER inevitability than a tsunami, earthquake, meteor strike, tornado, hurricane, or terrorist attack."

No, that isn't necessarily true. Look at the FAA, which has led to ever greater increases in airline safety, to the point where airline travel in the U.S. is safer than driving a car. Absent the 737 MAX debacle, airline deaths per mile had declined by multiple orders of magnitude since 1980.

SMR technology is being proven a safe and and cost-effective nuclear technology.

Also, the number of deaths from Three Mile Island, Chernobyl and Fukishima are orders of magnitude less than current coal or oil fired electrical generation. I don't see what pint you are seeking to make.

[AtlasBarfed]

Your comment is like a zoo of the nuclear industry's failure.

My point is that managerial incompetence is inevitable and YOU AGREE and that REGULATION IS NECESSARY for solid fuel reactors. But the point of numerous other posts is that REGULATION MAKES NUCLEAR UNECONOMICAL and needs to be reduced. But by your very admission, it can't.

Then, despite me stating the obvious that various nuclear arguments like "average deaths" and "average radiation released" are politically completely ineffective. Particularly since Fukushima. Does anyone in nuclear disagree that, whatever the logical reality of the stats, this argument is worthless? Yet you parrot it here.

I think it is funny you say "well you exclude the 737 MAX". Why would you exclude that from a discussion of managerial incompetence? THE 737 MAX WAS A DIRECT RESULT OF MANAGERIAL INCOMPETENCE. In fact the 737 MAX is a PERFECT example of the additional challenges of managerial incompetence in an age of vastly complex software stacks and control systems. Did anyone on Hacker News not see garden variety software corner cutting in the exposes on the 737 MAX?

Here is another problem with nuclear arguing for less regulation: people's faith in regulation and oversight is fundamentally worse now that it was a generation ago. Perhaps it is because of the republican elite war on government, perhaps it is greater awareness and spotlights from the internet, perhaps it is a result of industry lobbies undermining regulatory agencies and starving them and propagandizing against them for their short-term financial gain.

The public will not trust a for-profit company to:

- run a nuclear plant long term that can melt down

- properly transport the waste

- trust that the waste is secured properly (Yucca or whatever)

They will not. So you need a design that won't melt down (so if the operators screw up, it's not a disaster) and there's no waste transported through neighborhoods (that some scumbag / mobster won't dump on the beaches or in a swamp somewhere).

"oh that would never happen" Um, what did Fukushima do with its irradiated water? That wasn't even the mob.

You know what else happened in Fukushima? The government clammed up and wouldn't release any information. Some of that is Japanese culture, but still it was a cover up. The US Military was releasing more information about radiation release than the Japanese government!

If you want reduced regulation, you need to make a meltdown proof reactor and one that virtually eliminates the waste. As someone that isn't in the nuclear industry and has no economic interest in LFTR/MSR (are there even any companies left working on it in the US?), when I saw those two aspects of LFTR/MSR, that's when I got enthused about nuclear power.

...

"SMR technology is being proven a safe and and cost-effective nuclear technology."

Sigh, that is pure PR boilerplate weasel words.

[Georgelemental]

> The point is that solid fuel reactors are currently completely fucked from an economic standpoint. They are fundamentally economically noncompetitive.

If all of this is so "fundamental", then why does South Korea manage to build plants for cheap? And why has France managed to have its entire grid be nuclear-based for many decades? Please explain.

> I want the nuclear industry, nuclear lobby, and American research infrastructure to WAKE UP and start really working on economically viable reactors.

Then we must fix the regulatory incentives. That's how capitalism works: corporations chase profit. So if you want them to innovate, you make innovation the profitable option, instead of adding a mountain of regulation to block anything new.

[ZeroGravitas]

> its entire grid be nuclear-based for many decades?

This has a "60% of the time it works every time" feel that seems common when discussing the French grid.

https://www.statista.com/statistics/462535/nuclear-share-ele...

Why didn't they get to 100%, and why do people go out of their way to avoid discussing that?

[Georgelemental]

France nuclear share stopped growing because of the terrible policies of François Hollande—the president with low-single-digit approval rating, who singlehandedly turned France's formerly largest political party into small fry, because people hated him so much.

And then Macron decided to continue the insanity by following up on Hollande's unfulfilled promise to close the perfectly functional Fessenheim plant.

Then there are the "market competition" policies. It used to be that the French grid was entirely run by EDF, a state enterprise. And it worked well enough. But then the EU (with buy-in from complicit French politicians) decided to introduce "privatization"—except it's totally fake, as EDF has to sell energy to the private companies at prices set (to much lower than the market price) by the government. This has hurt EDF financially, and combined with other lacks in investment during the past decade or two means that they have lost a lot of organizational competence (skilled engineers are gone).

[Georgelemental]

> It is inherent to the nature of a solid fuel rod reactor, the incidence (and fear) of meltdowns, and the fear of nuclear waste.

So why do these factors not apply to South Korea? Last time I checked, the laws of physics are identical there and here.

> They have no interest in its development because it is a massive risk, they are desperately trying to eke a profit out of current nuclear plants

Everything nuclear is already a massive risk, that the NRC will decide tommorow that they are feeling grumpy so your billion-dollar years-long project is canceled. Of course companies won't assume additional risk on top of that! The only way to survive is to play it as safe as possible.