Micro molten salt reactor can fit on a truck, power 1k homes. When it's built

As the US Department of Energy (DoE) continues to look for ways to improve molten salt nuclear reactors (MSRs), a team from Brigham Young University in Utah has designed one it says can fit safely in the bed of a 40-foot truck.  The molten salt micro-nuclear reactor, which - once approved - will be built by Professor Matthew …

[Dante Alighieri]

Mb99 -> Tc99m

If this is generated continuously and extractable, you may well not need to produce electricity to profit!

Hell, it would be worth healthcare providers installing these on site for both purposes. If a refining module to get at the Mb is part of the design it would see a significant improvement in availability of funtional imaging in a lot of settings.

And for the science pedants the question of what is the half life of Tc 99 is usually incorrectly answered. Especially in hospitals and more worryingly often by those who *really*should know better.

No, it's not 6 hours ( no register time standard unit, so that's about 2.4 gov't u-turns)

[Slipoch]

Re: Mb99 -> Tc99m

So what is it if it is not 6 hours?

[Bill Gray]

Re: Mb99 -> Tc99m

Just checked the El Reg units table, and you're right; there's no time unit. This oversight should be corrected.

Any ideas from the assembled commentardiat, aside from the Gov't (US: Gummint) U-turn? (It'd be nice to have units for shorter and longer time spans. We could obviously have nanoGUTs, megaGUTs, etc., but I think we can do better than that.)

[MachDiamond]

Re: Mb99 -> Tc99m

If you want to work in government cycle units, they are 2, 4, 6 and 8 years. Or, the election intervals of major offices that sponsor, sustain or approve large scale projects that include government funding. The 8 year cycle is very risky as it mostly involves a president or some other top figure being elected to two terms. Totalitarian G-Cycles can be much longer or much shorter making those units difficult to use. Might as well use the El Sobrante Fortnight which can be anywhere from 2 weeks to a decade according to chief researcher Les Claypool.

[Alan J. Wylie]

Re: Mb99 -> Tc99m

Just checked the El Reg units table, and you're right; there's no time unit. This oversight should be corrected.

Microfortnight, surely, as used for the DEC VAX VMS TIMEPROMPTWAIT variable.

[Michael Wojcik]

Re: Mb99 -> Tc99m

Computery, but not very UK. Maybe something like the time it takes a standard kettle [cite relevant ISO spec] to heat a cup of water for tea?

[Korev]

Re: Mb99 -> Tc99m

Just checked the El Reg units table, and you're right; there's no time unit. This oversight should be corrected.

That's the ElReg of the past, injokes like these don't seem to happen much any more.

TBH I can't imagine that the BOFH has too much longer here :(

[IvyKing]

Re: Mb99 -> Tc99m

IIRC, half-life of 99Mb is 66 hours, the metastable 99mTc has a half life of slightly over 6 hours and 99Tc has a half life of 211,000 years. It takes a few days before the activity of the 99mTc drops below the 99Tc decay product.

One of the great things about thermal neutron induced fission of 235U is that the yield of 99Mo (Mo not Mb) is on the order of several per cent of the fissions. With an MSR presumably burning up 238U through fast fission, along with 239PU and 241Pu, I suspect separating the 99Mo from other Mo nuclides might be a problem.

[elregidente]

Re: Mb99 -> Tc99m

If these reactors are successful and proliferate, the supply of Mb will increase and prices will drop.

[JohnTill123]

Re: Mb99 -> Tc99m

Half life of Molybdenum-99 is 66 hours. So you need to extract it fairly quickly and use it within a few days.

[bonkers]

Re: Mb99 -> Tc99m

Molybdenum is Mo not Mb

[Arthur the cat]

Re: Mb99 -> Tc99m

If this is generated continuously and extractable, you may well not need to produce electricity to profit!

That's the alchemist's fallacy, presuming the price will remain high even though the supply massively increases.

[Michael Wojcik]

Re: Mb99 -> Tc99m

Half-life makes it somewhat inelastic as a commodity.

[Anonymous Coward]

Corrosion

They already use Zirconium Carbide as a coating for fuel rods. Couldn't they use that to line the pipes and containers? It should be resistant to the corrosion.

[Anonymous Coward]

Re: Corrosion

You have two types of corrosion to deal with: the chemical kind (fluoride salts are quite aggressive, and at 700ºC doubly so), and the nuclear, radiation kind which degrades the metals too.

That said, that problem has been solved. Materials have been developed and their deterioration is well understood so maintenance thereof is no longer a problem either.

[Dave 126]

Re: Corrosion

From this armchair, the belt and braces approach of one, making things ever more resistant to corrosion, and two, making the liquid less corrosive (as this team are claiming), seems sane.

On a practical note, whist individual parts can be coated with resistant ceramics, coating a join between two pipes is likely trickier.

[brett_x]

Re: Corrosion

a join between two pipes

talk about belt and braces

[Anonymous Coward]

A portable (stealable) nuclear reactor. What could possibly go wrong.

[Denarius]

yeah, really easy to hide a semitrailer with a hot hot load. no-one would notice

[Anonymous Coward]

If we can lose a 777-200ER airliner and 239 passengers, we can lose a MSR reactor on the back of semitrailer.

[Filippo]

If I understand correctly, the reactor is truck-sized. When it is actually operating, it will have to be hooked to cooling and turbines and whatnot, i.e. it will be in the middle of a fairly big building. I also suspect that if it has been operating, then it will need cooling before it can be moved. Overall, not very easy to steal.

[Neil Barnes]

Though there is the minor concern of what happens if some megalomaniac idiot decides to start a war in the vicinity, and lobs armour/concrete piercing missiles at it?

[Anonymous Coward]

Start a war in the vicinity of BYU? In the middle of the US?

[Anonymous Coward]

Considering the reaction of the more extreme members of the Republican party to the mid-term elections and threatening civil war, etc if they lose; yes, certainly possible.

One should not underestimate the degree of nutjob that resides there.

The love/hate relationship with the USA is strong for this Brit.

[Anonymous Coward]

I thought it was the dems saying 'vote for us or there will be civil war'? They did start the last one after all.

[cmdrklarg]

Turn down that brightness on that projection please.

[Anonymous Coward]

An MSR does not go kaboom like a LWR. First of all, as it does not use hyperheated steam as a first heat transmissor, you have no high pressure radioactive cloud escaping at high velocity if you make a hole somewhere, you'd get some glowing goo dripping over the vessel so it stays a local problem (I wouldn't touch that, though).

Secondly, if you willingly destroy the cooling system of an MSR you simply trigger the safety release which will dump the reactor mass (liquid) into a couple of storage tanks and that will be that. No kaboom there either.

Thirdly, the reaction is also self stabilising due to a number of factors - it cannot go any hotter than about 700ºC so even if the salts remains in the conatiner you simply have a heater. Again, no kaboom.

Basically, I cannot ever see an MSR feature in any thriller as they're boringly safe in comparison to light water reactors.

[Arthur the cat]

Basically, I cannot ever see an MSR feature in any thriller as they're boringly safe in comparison to light water reactors.

You massively underestimate Hollywood writers' ability to completely ignore science in their scripts. Moonfall anyone?

[Loyal Commenter]

Forget that, "The Core".

[Anonymous Coward]

Wait, are we back with Apple?

:)

[NXM]

film plots

Voyage to the Bottom of the Sea where the Van Allen belt catches fire?

Or Barbarella, which was entirely science-based. No, really, it was!

[Anonymous Coward]

Re: film plots

Who was thinking about the science while watching it? It would be interesting to ask what people remember about that film.

[ABehrens]

Re: film plots

I was impressed by Marcel Marceau's speeches..

[SonofRojBlake]

Re: Kaboom

Corbomite.

"Carbomite" is neither the stuff Kirk bluffed about having the Enterprise coated in (twice!), nor the stuff Han Solo got frozen in. Close to both though.

[Anonymous Coward]

Re: Kaboom

That's because it's new, he wasn't supposed to tell anyone about it. Now we have to shoot him.

Regards, the CIA.

:)

[Michael Wojcik]

An MSR does not go kaboom like a LWR.

And, of course, we already have plenty of things that go kaboom, many of them in motion. Fuel-delivery trucks, for example, or similar containers on trains. Grain silos. Blowing up a dam can do some, er, damage, as could blowing up chemical storage tanks. It's not like an attacking military won't have any good industrial targets if we don't deploy these things.

[Filippo]

The truck-sized thing will be in the middle of a building. I guess you would make it fairly sturdy and/or put the reactor underground.

You can't make it invulnerable, of course, but note that we still haven't had a major nuclear accident at Zaporizhzhia, despite everything that's going on over there (fingers crossed!), and a MSR power plant would be intrinsically much safer than that.

From what I understand, the MSR wouldn't be more dangerous than any number of industrial plants that deal with highly toxic materials. We've got plenty of those lying around, and we don't stay awake at night thinking about them. The MSR is probably safer than most of those, actually; the salt is not gaseous and actually pretty heavy; it won't get around much.

[Anonymous Coward]

In 1970 a friend did his degree "industry year" at a chemical plant in Billingham, UK. He showed me the muddy looking stream running past the perimeter. He said that if anyone fell in it then they wouldn't call an ambulance - just a hearse.

[Anonymous Coward]

Give the Tories a few months, we'll be there again!

[Loyal Commenter]

You end up with a puddle of no longer molten radioactive salts, which isn't exactly Chernobyl.

[Anonymous Coward]

Correct, it still needs a cleanup.

It doesn't magically become a mere salt lick for radioactive cows :).

[Spherical Cow]

Well I'm not going to lick it.

[TRT]

Can you recycle them in a moosion reactor?

[Anonymous Coward]

Would that not be technically be called a crust when it has cooled and hardened out?

Asking for a pedant :)

[GaryB_]

Not with molten salt so much. Not enough material and it will turn into a bunch of rock-like particles that could be essentially vacuumed up.

[Wellyboot]

Hazarding a guess, it would also be taken off the trailer and bolted down first.

[Pete 2]

> it will be in the middle of a fairly big building.

So size-wise, will this design be any more attractive, flexible or economical than a Rolls Royce SMR. Which is claimed to offer an entire power generator in the space of two football pitches? And that outputs 50 times the power.

Though I imagine all the transmission infrastructure would increase that considerably/

[Anonymous Coward]

The SMR is pretty poor on fuel burn and will contribute to the increasing pile of hard to deal with waste. Fast reactors can be run on the existing waste which resolves 1) the supply of fuel and 2) what to do with what we already have.

[Anonymous Coward]

Not a rocket scientist, or boffin - but where does the energy come from to melt the salt come from?

Maybe need to invent a reactor that runs on vinegar. Was thinking pepper, but would be too silly...

[Phil O'Sophical]

A fish-on chips reactor?

[BenDwire]

Bravo sir!

[TDog]

That's aweful

It had me splitting my sides in reaction.

[Filippo]

I guess you melt the salt with external energy; after that, you add the fuel and it stays hot on its own. I don't think the initial energy input is very large, compared to what you get after it's up and running.

[Loyal Commenter]

Presumably, the reactor is warmed up first, and fuel is poured in already molten.

[Anonymous Coward]

The SMR is pretty poor on fuel burn

Assuming you mean MSR, their fuel efficiency is truly spectacular compared with an LWR: an MSR converts over 99% of its fuel into power, as opposed to the current LWRs which can't even get above 1% so that's between 100 and 200 times better.

Unspent fuel and byproducts are substantially better with MSRs so I don't know where you got your data from.

[Filippo]

There was an article going around a few weeks ago, maybe a few months now, that stated that SMRs ("Small Modular Reactor", not "Molten Salt Reactor", although I guess one can also be the other) produce large amounts of waste (per unit of power, compared to LWRs).

I am not a nuclear engineer, and I have absolutely no idea of whether that article was correct, or exactly to which reactor types it applied, or what exactly it defined as "waste".

[Richard 12]

Compared to a bigger one the same, yes

It just comes down to scaling.

For a given design, the output goes up with the amount of fuel - approx. volume - of the reactor, but most of the waste is the enclosure, which approx. scales with the surface area.

That only applies to the same design though.

[Anonymous Coward]

No, I did mean SMR, not MSR. I do know the difference :) And the SMR is not a good idea.

[Fred Goldstein]

Right. The SMR has the same problems as other boiling-water uranium-cycle reactors. It's your basic "Atoms for Peace" dual-use 1950s model repackaged as an SUV rather than with tail fins.

[Disgusted Of Tunbridge Wells]

You mean there aren't going to be dozens of these doing laps of the M25, causing rolling black-outs if one of them develops a flat tyre?

[Arthur the cat]

You mean there aren't going to be dozens of these doing laps of the M25

With an inverse trolley car system for power, the trucks feeding electricity up to overhead cables.

[Toni the terrible]

Not easy to steal? but you know someone would try - if not Crims then State Actors etc

[Xalran]

Not much.

As mentionned, it's designed in such a way that It cannot go boom even if you poke it the wrong way.

It will just go back to a safe, cold, stable state.

The worst that can happen is that some idiot poke a hole in the thing and the reactor content spill out over some area... And honestly if that happen, the Fluoride salt polution is probably worse & more dangerous than the radioactive one.

[zuckzuckgo]

> What could possibly go wrong.

Someone might put it in a DeLorean and then all kinds of chaos will follow. I saw a documentary about this many years back. It even predicted the Trump presidency.

[Anonymous Coward]

"and it generates valuable elements accessible for reprocessing after the reaction is complete."

That's a... unique... framing of high level nuclear waste.

[Anonymous Coward]

The whole point of MSR-based reactors is that they produce substantially less nuclear waste than the things we've been running for decades - as a matter of fact, they can even recycle some of it (although it must be said that that is a rather tiny amount, the benefit lies in not producing it in the first place).

Worth noting: current nuclear reactors use 0.5% of their fuel before it needs extracting, and even after (super expensive) reprocessing that percentage is not that much better. Ergo, 99,5 of the fuel input returns as waste, and here with extremely long halflife. MSRs do pretty much the reverse as a side effect of how they work: 99.5% of their fule is converted into energy, which does not only result in less waste, but that waste also has a much shorter half life.

Add to that that aformentioned fuel is Thorium which is presently a waste product (of rare earth mining) in itself and close to immediately usable in the form it occurs as opposed to the expensive enriching of the rather rare Uranium in "traditional" reactors and it's actually a scandal that we ever started with the other approach, but hey, bombs :(.

Personally I can't wait until we have MSRs online because that will very much change the landscape. But the interesting challenge will be that the corrosion problems have been solved and the solutions patented - by the Chinese. How that's going to play out I don't know, but it'll be interesting.

[Filippo]

> But the interesting challenge will be that the corrosion problems have been solved and the solutions patented - by the Chinese.

I wouldn't worry too much. They're patents. They are only protected by the rule of law. If it gets to the point where we really need to make MSRs with that tech, and the Chinese really won't license them, we'll just ignore the patents, handwave some excuse, and use the tech anyway.

[MachDiamond]

"I wouldn't worry too much. They're patents. They are only protected by the rule of law."

The trick is never to patent the entire thing. Just enough that the missing parts only work if the patented things are used. If nothing is published about the missing bits, it winds up as just as much of a science project as it was before. In the US, even if the courts wanted to ignore the patents, it would be very tough for them to do it. It would take some sort of legislative pixie dust premised on the manufacture of a national security issue if one wasn't near to hand already. Five will get you a thousand that China will file patent applications in the US for US protections. They'll do the same in the EU and everywhere else. It's not like they are strapped for cash to do it.

[Fred Flintstone]

The trick is never to patent the entire thing. Just enough that the missing parts only work if the patented things are used

In that context I can only admire Singer who invented the sewing machine. All he patented was the hole in the needle. Pure genius.

[Filippo]

> It would take some sort of legislative pixie dust premised on the manufacture of a national security issue if one wasn't near to hand already.

Exactly! If it becomes really important, the legislative pixies will start crapping dust by the truckload. Some governments already ignore patents on things like e.g. vaccines, and power generation is potentially more important than that. Put it plainly, patents can withstand a lot of pressure, but not infinite pressure. I'm 100% sure that the Chinese understand this very well, and will not demand unreasonable licensing terms. Either we'll come up with alternative designs, or the Chinese will make some money, but that's about it. We won't be left without the tech; that just doesn't work.

[Anonymous Coward]

The problem is that the US have been hammering China for years for doing the exact same thing as the US did themselves to get their industrial revolution started: ignoring patents (that's why some companies were on opposite sides of the country).

The moment the US changes that tune, all bets are off when it comes to any future patent compliance by China and I'm not sure the US is ready for that - not only would a lot of lawyers lose work (which is the one good thing), but it would also put a damper on innovation.

Now I know that especially the Republicans are evidently not big on consequence analysis, but that doesn't mean they don't exist..

[MachDiamond]

"the legislative pixies will start crapping dust by the truckload"

I agree with that. They will and damn the consequences. The problem is that while ignoring a patent on the latest Neodymium magnets might just create something along the lines of a strongly worded communication through channels, not respecting patents for something as big as MSR technology could lead to embargoes on crucial goods and restrictions against large corporations with operations in China. If GM were effectively shut down in China in retaliation, US politicians' heads would be on the block waiting for the axeman to finish honing his blade.

[Toni the terrible]

Manifest Destiny Rules over patents

[PCman999]

The Chinese ignore patents anyway and one would only have to tweak the %'s of the alloys to get materials just as good but not covered by the patent. It's not as though there is only one possible solution to the issues at hand.

[TDog]

99.5% of their fule is converted into energy

As any fule kno (copyright Molesworth, N).

[Anonymous Coward]

Re: 99.5% of their fule is converted into energy

Yes, my lysdexia occasionally rules KO..

[Fred Goldstein]

I am not sure that the article actually refers to the LFTR thorium-cycle reactor, which I agree is a very promising design. The article actually seems to refer to a uranium-cycle molten-salt reactor. Like the LFTR it apparently doesn't go critical when it gets hot, and the reaction slows when the liquid salt drains, but its fuel cycle is still based on uranium and thus it has a lot of long-lasting isotopes in its waste. Not as much as the 1950s designs we have been using, but much more than an LFTR.

I suppose the advantage of the uranium cycle is that it creates a revenue stream for the uranium mining and refining ($$$) industry, like conventional fuel-rod reactors, while the LFTR burns thorium, which is a waste product of neodymium mining and refining and thus essentially free for the taking. And to the vulture capitalists, free fuel is bad; they are looking for revenue streams to tout to stock speculators, not to save the world.

[MachDiamond]

"free fuel is bad"

The waste stream will suddenly find value and no longer will be free. Right now, Thorium costs mining companies a bunch of money as it's a radioactive hazardous waste. If they could get $1/ton it would eliminate the cost of disposal and make the Neodymium and other rare-earths worth going after. China did a good thing by the government taking on the unneeded Thorium and it's made them the leader in rare-earth metals. They likely figured that the Thorium would be worth something down the road and it's a very big country so they could find some place to store out of the way. In more democratic countries a lash up between private industry and the government like that would engender a whole slew of lawsuits and cries of "unfair" (whatever that means).

[Toni the terrible]

If you can use it it isn't waste its a profitable byproduct

[Slipoch]

The published journal papers I have seen on small reactors show that the emissions created in building them is far above using coal power for the same output wattage over the same lifetime.

Would be interested to see how these salt ones stack up against that in environmental cost of production vs the total output and cost of input.

[Anonymous Coward]

Plenty of informative videos on Youtube will tell you that they stack up so well against both traditional fuels and current nuclear reactors that a lot of scientists have literally spent a llifetime trying to get this off the ground against the existing nuclear industry which is making a fortune being paid for handling all the problems.

Got a piece of land not good for anything else? See if you can store nuclear waste - an income for centuries! Need bombs? We make the kaboom stuff! (not a feature of LFTRs). Need fule? Have this, of which you can only convert less than 1 percent into actual energy, and we will charge you for reprocessing again!

It's criminal that we didn't listen to the scientists who came up with this (the majority of whom have actually died of old age by now).

BTW, those YT videos will also point you at published and reviwed sources of information if you want to read through it - it's well documented..

[Arthur the cat]

Need bombs? We make the kaboom stuff! (not a feature of LFTRs).

Unfortunately wrong. See this article from Nature that shows that the processing of salts from Thorium based MSRs can produce U²³³ far more safely than getting it from conventional reactors. U²³³ can be used pretty much like U²³⁵ for making bombs.

[itzman]

U233 and bombs...

Really not a good idea. Its a nasty hot material and you dont want your military anywhere near it.

[sitta_europea]

[quote]

Unfortunately wrong. See this article from Nature that shows that the processing of salts from Thorium based MSRs can produce U233 far more safely than getting it from conventional reactors. U233 can be used pretty much like U235 for making bombs.

[/quote]

Except that you can't handle the U-233.

U-233 is invariably contaminated with U-232, which is hideously radioactive so you're looking at isotope separation down to ppm levels just to be able to handle it. Ask any Iranian how easy it is to separate similar isotopes down to that level. As for making bombs, U-233 is a lot more like Pu-239 than it's like U-235 but the impurity problems remain, and are much more serious for U-233 than they are for Pu-239 where the acceptable impurity is a few percent, not parts per million.

Oh - I *am* a nuclear physicist.

[Arthur the cat]

U-233 is invariably contaminated with U-232, which is hideously radioactive so you're looking at isotope separation down to ppm levels just to be able to handle it. Ask any Iranian how easy it is to separate similar isotopes down to that level. As for making bombs, U-233 is a lot more like Pu-239 than it's like U-235 but the impurity problems remain, and are much more serious for U-233 than they are for Pu-239 where the acceptable impurity is a few percent, not parts per million.

Did you actually read the Nature article? It's not isotope separation, it's chemical separation of Protactinium 233. To quote

After irradiating thorium with neutrons for around one month, chemical separation of 233Pa could yield minimal 232U contamination, making the 233U-rich product easier to handle. If pure 233Pa can be extracted, then it merely needs to be left to decay to produce pure 233U.

And

The separation of protactinium from thorium is not new. We highlight two well-known chemical processes — acid-media techniques and liquid bismuth reductive extraction (see 'Ways to obtain pure protactinium') — that are causes for concern, although there may be others. Both methods use standard nuclear-lab equipment and hot cells — containment chambers in which highly radioactive materials can be manipulated safely. Such apparatus is not necessarily subject to IAEA safeguards.

Oh - I *am* a nuclear physicist.

Bravo. Well done. Shame it's chemistry that mostly matters here.

[MachDiamond]

"Oh - I *am* a nuclear physicist."

Then you'd know that bombs made from U233 broadcast their location to everybody and also have a nasty side effect of destroying electronics near them. It's not too hard to store Pu based bombs in a way that blocks alphas and betas, but gammas are a B*tch.

[MachDiamond]

"Got a piece of land not good for anything else? See if you can store nuclear waste - an income for centuries! "

The Nevada Proving Grounds fit that description of being not good for anything else. They already store nuclear and hazardous waste on it and monitor it for trespassers.

[MachDiamond]

"The published journal papers I have seen on small reactors show that the emissions created in building them is far above using coal power for the same output wattage over the same lifetime."

What type of small reactor and what forms of pollution? A big issue with the PWR is the containment building needs to be large and strong to contain an incident that flashes the water being held under boiling by very high pressure. The expansion from liquid water to gas is on the order of 1000:1 which is why the containment building is so large. An MSR such as a LFTR operates at ambient pressure so a huge thick concrete dome is not required. There is still a need for impact protection in the case of an attack. The use of CO2 as the working fluid might mean that siting an MSR near another process that produces CO2 might be very symbiotic although the gas shouldn't escape during normal operation.

Not all pollution types can be equated with each other. I'd find it better to deal with some CO2 from concrete than a whole bunch of particulate matter put in the air and a radioactive pile of fly ash that nobody has seemed to find a use for. Does it make sense to use heat from the reactor to drive a Sabatier process to make CH4? At least in the near term, natural gas is still needed even if the goal is to wind down its use in residential buildings.

[Anonymous Coward]

The default SMR operating temperature also comes close to the heat required for the most efficient process to produce hydrogen, and the hydrogen story too is far from over.

[Fred Goldstein]

I'm surprised your comment is getting so many negative votes. Current types of uranium-cycle reactor (PWR, BWR, etc.) do appear to be very much *net negative* in how much energy they create vs. how much goes into building them, running them, mining the fuel, refining the fuel, disposing of waste, and post-operation site cleanup. Molten salt designs may have a different equation, though anything with a uranium-based fuel cycle is highly suspect. Thorium avoids that.

[Anonymous Coward]

Uranium cycle with fast neutrons works too and is a gateway to thorium. But when you say 'breeder' people instantly think 'bomb'.

[Kevin McMurtrie]

I'm not a nuclear physicist

Curious - 10 MW is more continuous power than the burst of heat from a crushed Tesla. When it's said to be meltdown proof, does that mean a yellow hot core sitting on a burned-out platform but not immediately leaking? How much time do you have before impurities in the salt become a problem with a failed reactor?

I like the idea of easy nuclear power but know that PG&E would need extreme idiot proofing if they decide to operate them.

[Anonymous Coward]

Re: I'm not a nuclear physicist

The reason an MSR doesn't go into meltdown when you leave it alone is because the reaction needs to be continuously encouraged to happen (known as "fertile") - it's the opposite of the chain reaction of current reactors ("fissile") which needs to be slowed down to avoid the earth shattering kaboom. This video may help too.

Thus, if there is a problem you can simply pull the plug at the bottom of an MSR, let the liquid contents flow out in a receptacle underneath and it'll coll down as it's no longer reacting with the radiation source in the reactor, as opposed to having a failing cooling system resulting in a radioactive blob that will slowly melts its way past all those lovely acquifers that we drink from towards the centre of the earth because there's nothing shutting it down.

The safety of MSRs is due to a number of factors so substantially better than current reactors that we should have switched after Chernobyl, but the problem was the super corrosive liquid salt that they're named after (MSR = Molten Salt Reactor): it took a lot of work to develop materials that could handle that.

We're now at a stage where we can, and we should.

[MachDiamond]

Re: I'm not a nuclear physicist

The AC missed some of the finer points. An MSR in many forms needs to have the liquid radioactives in a container set up to slow neutrons down (thermalizing) so they have a better chance of being useful. Fast neutrons don't work. This means that if the reactor is drained into a suitable container, there is nothing in that container to slow neutrons down and the reaction screeches to a halt. The drain plug can be a salt that's kept solid through cooling so if the cooling goes away, it melts and the main reactor vessel will drain. Lose power or have some huge fault and the operators can run away leaving the system to shut down on its own.

The enrichment of U for PWR's is not enough for them to go "boom". They'll melt, but they won't suffer a nuclear explosion. The explosions at the Fukushima plants was due to a build up of Hydrogen since hot water under pressure will split into H and 02. This is why you will see re-combiners as part of the system in PWR reactors. They are there to get the H and O2 back together again so they don't go boom. Kill the power and the re-combiners stop working. The chain of cascading problems at Fukushima sealed its fate. If handled correctly, the reactors would still be around in one piece. It goes to show that having something that's "walk-away safe" is a major step forward.

[Anonymous Coward]

Re: I'm not a nuclear physicist

I wanted to keep it simple :)

There's also the fact that it self stabilises - if things get too hot you get again neutrons to fast to cause a reaction plus a greater atomic distance so the reaction automagically throttles down to regain that equilibrium. This is one of main reasons MSRs will work well in a grid supply system, they're by default load following. Extract more energy for power and they'll adjust accordingly, extract less and it throttles down to match.

Personally I am glad to see more and more attention paid to MSRs, even in the US where it was actually invented.

[Loyal Commenter]

Re: I'm not a nuclear physicist

Also worth noting that the last-resort safety cut-out on these is a salt plug that meths if it gets too hot. The whole lot empties into a tank without any neutron moderators, and the reaction stops. It's an absolutely passive fail-safe system.

[Loyal Commenter]

Re: I'm not a nuclear physicist

*melts not meths. Stupid fingers.

[Xalran]

Re: I'm not a nuclear physicist

The worst that can happen is if an idiot pokes a hole into the reactor core and the molten salt spill over an area... if it's a bit of landscape some serious chemical fluoride cleaning will have to be performed ( the radioactive contamination is less dangerous than the fluoride one and will be delt with during the fluoride cleanup. ), like any chemical spill.

So if the spill occurs in a controlled environment ( don't expect these trailer sized plants to actually sit on a trailer except for military purpose ) you'll have a concrete with some lining pond under the core to keep the molten salt in a limited area in the event that an idiot poked a hole in he thing.

And since the radioactive material is mixed with the molten salt, if the core gets emptied, no metldown can occurs.

[JohnTill123]

Re: I'm not a nuclear physicist

"the radioactive contamination is less dangerous than the fluoride one and will be delt(sic) with during the fluoride cleanup"

That's the most frightening thing I've read recently.

I am a physicist, and I'm very familiar with CANDU PHWR tech. Natural uranium fuel, heavy water moderator, low power density, refuel while running. Very efficient and well understood and running well for decades.

The promises about these small modular reactors of wonderful safety and extreme efficiency are all wonderful, but you are putting a LOT of extremely reactive and corrosive molten salts and radioactive material in a container made out of some sort of new magicunobtanium material that will do what no other material can do and resist damage.

That's a REALLY high power density and a LOT of very dangerous stuff: If the flouride salt is MORE dangerous than spilled and concentrated radioactive reactor fuel, then it is very dangerous indeed!

So please build the first of these somewhere really remote, and VERY far away from drinking water aquifers and put them in a containment building just in case some ISIS clowns decide to fly an airplane into them. When they've been running for a few years and there's good evidence of safety and no "we didn't think of that..." problems, then and ONLY then consider putting them somewhere closer to home.

[Anonymous Coward]

Re: I'm not a nuclear physicist

Don't worry, that has already all been worked out. If you're a physicist I'm surprised you do not seem to be aware of the developments in this area as it's very easy to find and extensively documented.

Have a read, worth it.

[Loyal Commenter]

Re: I'm not a nuclear physicist

I'm a chemist (well, my degrees are in chemistry anyway, I don't actually work as a chemist). Fluorides are horrible, horrible things. I would seriously hope that these things, since they are likely to be heavy metal fluorides, aren't very soluble, so wouldn't leach into water supplies easily, but I would also seriously hope that there's secondary containment, and then something like a sealed concrete floor.

But basically, fluorine chemistry rings alarm bells, and that comes down to it being the most electronegative element. Even its salts, which are supposedly pretty much inert (ignoring the idea of Lewis acids here) can be nasty things, biologically speaking, and that's before you get into the heavy metal part.

[Richard 12]

Re: I'm not a nuclear physicist

Yup, horrible stuff. You don't want to touch it, and want to be very careful about containing and mopping up spills. The salts being solid at RTP does help with that, of course.

Fluorine stuff is pretty commonly made and used in chemical plants - refrigerants, steelmaking etm

Techniques for handling it are well known.

[Anonymous Coward]

Re: I'm not a nuclear physicist

What about my toothpaste?

[Fred Goldstein]

Re: I'm not a nuclear physicist

IIRC both toothpaste and LFTRs (thorium cycle) use sodium fluoride. It is not that dangerous by itself. The hard part of the LFTR is that it needs regular decontamination via bubbling in gaseous fluorine. Thus the plant needs a fluorine generator. Not radioactive, but seriously nasty chemically. That is, of course, an engineering problem, and it is still only a recipe for local, short-term problems, not long-term radioactive contamination.

Conventional reactors need constant cooling, even after scram. Hence the concern at Zaporizhzhia, where the orcs are playing with something worse than fire, and have no comprehension of how dangerous it is.

[Loyal Commenter]

Re: I'm not a nuclear physicist

It contains a very small amount of fluoride ions, which are supposed to intercalate with the calcium phosphate in your tooth enamel and strengthen it, IIRC. You are not supposed to swallow toothpaste, and, to be fair, if you swallowed enough for the fluoride to be toxic, you'd probably be spewing up frothy minty goodness everywhere first.

[Loyal Commenter]

Re: I'm not a nuclear physicist

Refrigerants are a different kettle of fish, because they are covalently bonded (and fluorine-carbon bonds are pretty strong). The ones that are toxic tend to be toxic for different reasons (usually related to the free pairs of electrons liking to intercalate into things)

[Loyal Commenter]

Re: I'm not a nuclear physicist

...BTW, covalent fluorides tend to be immiscible in both water and organic solvents, due to the fact that the orbitals containing the free pairs of electrons are small, because of the element's electronegativity. This is why PTFE (polytetrafluoroethylene, better known as Teflon™) is used as a non-stick surface, because it repels both water and oil.

In general, in chemistry, you can either dissolve something in water / another ionic solvent (if it is an ionic compound), or in an organic solvent if it is covalently bonded. The choice of organic solvent depends largely on the dipole of the thing you want to dissolve, so things like organic acids dissolve well in solvents with a large dipole, such as ethyl acetate or dichloromethane, and things that are non-polar dissolve well in non-polar solvents, such as cyclohexane. The adage is "like dissolves like", and nothing is quite like a fluorine compound.

[TRT]

Re: I'm not a nuclear physicist

I have indeed seen the results of a fluorine flask rupture. You know those urban explorer videos of structures abandoned decades ago? A bit like that but without any signs of living matter (like plants) and after only the couple of hours it takes to pump the room out safely.

[Loyal Commenter]

Re: I'm not a nuclear physicist

Elemental fluorine is a nightmare, because it will react with pretty much anything you can think of (xenon tetrafluoride is a stable compound, and xenon is noble gas, elements which are notable for being the most unreactive things about).

In general, if you are thinking about using fluorine for something, or the nastier fluorine compounds, such as HF or FOOF, the first, and last, advice I will give is, "don't".

[Anonymous Coward]

Re: I'm not a nuclear physicist

I would also seriously hope that there's secondary containment, and then something like a sealed concrete floor.

Oh yes, it's still radioactive sludge so nobody is going to cut corners there (kinda hard to get it licensed otherwise), but you're still dealing with something that is far easier to manage when it comes to risk. An LWR gives you all sorts of fun problems like irradiated water (reactor as well as storage pools), storage space, high pressure radioactive steam you need to contain - there are fewer dynamic risks to manage with liquid salt.

It's also not the only place this is used as a heat transport medium - solar concentrator towers use it too.

[Anonymous Coward]

Re: I'm not a nuclear physicist

You remined me of this strip about chlorine trifluoride :).

[Loyal Commenter]

Re: I'm not a nuclear physicist

I am reminded of FOOF, and the advice, "don't".

[Anonymous Coward]

Re: I'm not a nuclear physicist

There is a whole branch of chemistry that seems obsessed with sticking fluorine to things. It might be the same bunch who like sticking nitrogens together like some atomic scale jenga tower.

There is a great book called 'Ignition' all about rocket fuel chemistry and the amount of work they did with fluorine is spectacular as no-one got killed.

[MachDiamond]

Re: I'm not a nuclear physicist

"The worst that can happen is if an idiot pokes a hole into the reactor core and the molten salt spill over an area"

The test reactors built in the US did have a containment around the reactor in case something broke. It would be very messy, but would keep the materials out of the environment.

[bolangi]

This is the loop that contains the fissioning uranium fuel that powers the reactor.

It seems doubtful that there is a system for removing all the daughter products.

How will it generate electric power? It will pass the heat off to a steam turbine which is not included in the 40' shipping container.

[Anonymous Coward]

The output of any reactor is always heat. How you use that heat is more a design decision.

[Filippo]

The shipping container is for the reactor. It would be housed in a building. The turbines will be in the adjacent building. Also, there will be an office. A maintenance area. Parking lot. Etc. All the things that make up an actual power plant.

Nobody said that you'll have a 40' shipping container sitting somewhere with a power line coming out of it. It is, however, very good that the most complicated and delicate part of a power plant fits in a shipping container.

[Screwed]

Concentration on the size of the reactor tends to read as if an artic turns up, the reactor gets put on a prepared slab, and someone turns up to connect some cables.

We need the full scale of the plant to be clarified.

If each one can power a thousand homes, we'd need 3634 (2020 figures) for London alone - and that's just for houses. Add in the extras you identify, and fitting them in will be extremely challenging!

[Wellyboot]

You've hit the nail square on!

The area occupied¹ by small generators compares very badly with full sized traditional power plants though one of these will probably occupy less area than 10Mw of wind or solar needs.

I can't see many situations where a 10 Mw active generator is economically feasible compared to running cable for a few miles to an SMR (Twenty/thirty times the power output) but the designers may well be looking closer to home. Utah (B-Y uni home state) has a fairly sparse population outside of the cities, these could potentially find a place given the challenging landscape conditions any large scale infrastructure development would be faced with (very expensive per head of population).

¹300 of these won't fit on the Hinkley-C (3+ Gw) site area.

[Toni the terrible]

Well make a giant MSR then!

[MachDiamond]

"Well make a giant MSR then!"

If you are looking to supply power to London or New York, why not?

[Loyal Commenter]

Even if you stack them up like shipping containers? Assuming they are the same size as a standard shipping container, five high, I make that about 13m tall (a 4-story building or so), with a footprint of about 1,800 m², or an area of less than a quarter of a football pitch. The Hinkley C site is much larger than that, at about 525,000 m²

Of course, you're going to need space for heat exchangers and turbines, but unless I've got a decimal point out by several places there, I'd say you've got your maths wrong.

Even if you don't stack 'em, There's much more than enough space on the Hinckley C site to lay out 300 things the size of shipping containers. I wouldn't actually be surprised if there are actually more shipping containers on that site than that, right now.

[MachDiamond]

"Even if you don't stack 'em, There's much more than enough space on the Hinckley C site to lay out 300 things the size of shipping containers. I wouldn't actually be surprised if there are actually more shipping containers on that site than that, right now."

The full layout will be much much larger. These would still need some sort of safety containment, power conversion, cooling and enough room to have access for heavy cranes and a buffer zone. If something bad happens to one, you don't want to have the need for a zone that shuts down another dozen.

[Loyal Commenter]

So, if the containment, and so on were ten times the footprint of the reactor, you'd still have space. I'm assuming you would be funnelling all the heat into a smaller number of turbines as well, not having one turbine per reactor, because "efficiency," but for something for which the primary purpose is outputting heat, and which has its own closed loop for fuel processing, the plumbing should be "relatively" simple.

I would have thought that containment for one of these things would essentially be composed of a glorified steel tank underneath it, and some radiation shielding around it to stop the fast neutrons it gives out when running. I don't know much about the engineering of such things, but I find the idea that it would have a surface area that much larger to be unlikely.

[TRT]

How many can you fit, say, on the footprint of a motorway service station? And how many recharges of a Tesla can it do before it runs out of fuel?

[MachDiamond]

"How many can you fit, say, on the footprint of a motorway service station? "

Maybe one.

"And how many recharges of a Tesla can it do before it runs out of fuel?"

Answering that requires a whole bunch of additional data. It's like asking how many packages could you tie up with a ball of string.

[MachDiamond]

"Utah (B-Y uni home state) has a fairly sparse population outside of the cities, these could potentially find a place given the challenging landscape conditions any large scale infrastructure development would be faced with (very expensive per head of population)."

Low hanging fruit first. Big cities and areas with high power demand industries make the most sense to get an MSR plant first. It then has to be calculated whether the power losses for long transmission lines make more sense to accept over adding SMR's for sparsely populated areas. In the mean time, more people will be adding solar to their homes so the requirements for the grid will change. On the other hand, more EV's might add needs in places where there hasn't been much. To make firm plans this year is a waste of time. Solve a bit and reevaluate when the time comes.

[Filippo]

I suspect that one power plant can and will fit more than one truck-sized reactor. I'm thinking ten or twenty or more.

Power-per-square-meter is unlikely to be as good as a giant reactor, of course, but it wouldn't be that bad, and the logistics would be a whole lot easier.

[Loyal Commenter]

There's also the situation where you can have a number of these, and be taking them in and out of service to meet demand, for maintenance, and so on, which sounds, to me, a lot easier than doing maintenance on an operating PWR.

The individual reactor could even have a relatively short lifespan before being emptied, towed away, stripped down, cleaned up and recycled, the sort of design decision that traditional nuclear plants make very difficult.

Admittedly, that "cleaned up" step is probably not a simple as phrasing it with two words may suggest.

I think the key here is probably flexibility.

[Anonymous Coward]

One of the features of an MSR is that it can actually be restocked while live - that's one of the benefits of the liquid loop (another one is live continuous extraction of the byproducts such as gases).

I think the main attraction of this solution is point power: instead of needing to run long supply lines you basically dump one or two containers (the second one to convert the heat into whatever you need) on location and get going. That was in general an MSR benefit: put power where you need it. Take, for instance, steel or aluminium works who need power to operate: you can use both heat and power from this.

[Loyal Commenter]

One of the features of an MSR is that it can actually be restocked while live - that's one of the benefits of the liquid loop (another one is live continuous extraction of the byproducts such as gases).

I would have thought that there would still be corrosion of parts, maintenance of pumps, and so-forth, which might require taking it out of commission to fix, and I would imagine the reaction vessel itself would have a limited lifespan, what with all the neutrons zipping through it.

[John Robson]

One major reason for this is that an existing thermal plant (coal, gas, biomass, whatever) can "simply" have several of these delivered, and replace the boiler with steam from these.

Although reading the article... the actual reactor is 4' * 7', so the generation might well be on board the 40' container.

[Loyal Commenter]

The rest of the container is probably the fuel loop and reprocessing.

[MachDiamond]

"It is, however, very good that the most complicated and delicate part of a power plant fits in a shipping container."

I'm not sold on fitting it in a standard shipping container as the best goal. I would like a design that can be built in a factory rather than on-site and is modular enough to be able to be shipped on standard sized trucks. If all it takes is fitting modules together at the location and giving the whole thing a good testing before going hot, that's a good thing. There still needs to be some things done on-site such as building some sort of containment and installing a drain tank down hill of the reactor core.

It may also be a good idea to come up with a 5-year design where all of the MSR's built in that period are based on one set of plans. Nothing changes other than safety critical fixes until the next 5-year period where any new installations are upgrade to the next set of plans. This would mean that spares make sense to keep on hand and not every installation is bespoke so operators and staff can move from place to place and not have to spend much time learning after each move.

[MachDiamond]

"It will pass the heat off to a steam turbine which is not included in the 40' shipping container."

If a steam turbine is used, that's going to mean an expensive power generation section as well as the need for cooling water since very thermal system needs a hot and cold side to realize any output.

Anybody have any reference material on turbine costs for various sizes? I'm expecting that a single 1GW rated turbine is much less expensive than a bunch of smaller ones that add up to 1GW.

The 40' shipping container is not that great for security either. Speaking of security, all of these small plants will need it. Even if it's just to keep the independent business people from salvaging the metals just sitting there. Never mind some more organized group that might find it interesting to cause or put themselves into a position where they could cause something bad to happen. "It would be a real shame if something happened to your nice reactor. Yes indeed, a damn shame."

[Kristian Walsh]

It can fit in a shipping container. It won’t live in one. It probably wouldn’t even be shipped in one. The inventors mentioned this only to illustrate how small the system is compared to a traditional fission reactor. They are not going to try build a bloody power station in a 40-foot container.

The most likely configuration is a battery of “larger-than-a-container-but-still-fairly-small” reactors to provide a much more controllable, and safer, source of heat to drive steam turbines than using a single large PWR, with the added advantage of being able to perform rolling maintenance without needing to take the whole thing off line.

[John Robson]

Shipping containers have a really useful property though... they can easily be shipped.

Trying to disconnect anything which is transferring that much power is generally considered exciting, so I don't think theft is a significant risk.

[PCman999]

One possiblity for the future is new thermal couple designs that reached 40% efficiency with temps above 1000°C and of course it's just tiny lab size samples now. Most reactors are only about 30% efficient, high temp gas reactors at about 50% - so 40% is awesome for low maintenance, probably never wear-out thermal couples. Waste heat from the reactors is still hot enough to drive a turbine (like the way gas turbines have steam turbines attached for 60% efficiency with CCGTs) or to do district heating. Direct heat is very hot and good for process heat - able to replace fossil fuels in heat, non-electric areas for even more efficiency gains.

[Christian Berger]

How does one secure it?

I mean, sure it might be meltdown-proof, but what if someone goes there and either just takes the reactor with them or plants a bomb next to it.

Considering there are decent amounts of radioactive materials inside of it, using it as a "dirty bomb" seems a plausible scenario.

[Xalran]

Re: How does one secure it?

First the radioactive material is in the form of liquid... molten in a fluoride salt.

The wort that can happen if an idiot plant a bomb on a MSR core is some square meters of fluoride contaminated ground. ( that chemical contamination is worse than the radioactive )

Fluoride spill are ( somewhat sadly ) regularly dealt with in chemical plants so it's not really an issue.

( it will just need another layer of precautions due to the radioactive material, but that's just adaptating a known process )

[Loyal Commenter]

Re: How does one secure it?

What if someone goes to a refinery and plants a bomb next to it? Or a school? Or a hospital? Or your mum?

In case you don't get my point, if you put a bomb next to something, the problem is the bomb, not the thing it's next to. Standard practices apply to preventing people blowing things up with bombs, starting with fences, and moving up in sophistication.

[timrowledge]

Re: How does one secure it?

Oh, I dunno. That bridge in Crimea might be a good example of how the combination of ‘bomb’ and ‘thing next to bomb’ makes the problem much more interesting.

[Loyal Commenter]

Re: How does one secure it?

We could probably mitigate against that sort of thing by not putting a nuclear reactor on a public bridge...

[MachDiamond]

Not allowed.

An MSR is "unproven" technology so getting approvals to go hot will be very difficult. That sort of thinking is a major roadblock for many things, but new nuclear power plants get hit really hard. Why use diesel busses? They are proven technology and a PRT system is not (even though it is). Nobody is going to be tossed out of office or be fired for specifying diesel busses on a transportation project.*

There is also a problem with getting permits for the siting of reactors so just having more smaller ones is going to mean more billable hours for more attorneys. There are enough people that break out in hives and go into hysteria if "nuclear" is mentioned. It's that vitamin Sc deficiency rearing its head. If they also have a condition abbreviated by the letters "JD" it gets even worse as JD is a Sc antagonist doubling the problem.

*I just watched Inside the Factory where they showed the assembly of electric London busses so somebody got brave about specifying an electric vehicle. The drivetrain is sourced from BYD in China as a complete subsystem which is something of a bummer. They drive the sled right off the lorries when they're delivered and into the first assembly station.

[Anonymous Coward]

Missing the point ?

A reactor this size could potentially be dropped into existing power stations and use their turbines etc.

[MachDiamond]

Re: Missing the point ?

"A reactor this size could potentially be dropped into existing power stations and use their turbines etc."

Possibly. Although, it wouldn't make sense to replace a coal burner with a tiny reactor. It makes more sense to replace the burner with a reactor that's the same size. This depends on the remaining life of the turbine and ancillary equipment as well. Reuse of the same site for the same purpose could cuts some costs and it would also mean that the overall system is already aligned for inputting power at that node. While MSR's should be much safer, there are still constraints to have in place regarding population near the plant, wind directions and other facilities in the area.

[rivimey]

Re: Missing the point ?

As others have said, there's real benefit to multiple smaller reactors rather than pne massive one. Though I do wonder whether the unit size might be somewhat larger than is mentioned in the article.

[MachDiamond]

Re: Missing the point ?

"Though I do wonder whether the unit size might be somewhat larger than is mentioned in the article."

Something that would power a thousand homes isn't all that great. In a dense residential area, 1,000 homes takes up much less space than some may think. This is especially the case in areas where it's multi-family units and apartments.

An issue with wind and solar it those installations dropping their power at places on the grid where the original design didn't anticipate those inputs. The same problems that stem from that would also apply to using lots of SMR's in the same way. Re-fitting an existing coal plant makes more sense as the system has been designed and built to put a bunch of power onto the grid from that location. It might also make sense to increase the power and upgrade the lines and substations to handle it. All of the right of ways will have been in place for some time so there won't be the push back from needing to install a whole new set of pylons.

[gandalfcn]

How about CORE POWER (UK) Ltd?

[dai_electric]

Let's make a delivery! I shall avenge us!

<pic from RA2>

[VernRedHair]

Nuclear promoters always leave out key issues

As is common practice with nuclear power promoters key issues were left out from this promotional article. What fits on the trailer is far from what a practical power plant would look like. Numerous other large components would be needed. That includes a heavy radiation shield. Useful products from the fission reaction were mentioned but numerous other fission products would end up as high level radioactive waste (SNF). In the U.S. we were promised a deep geological repository in the 1950s yet there is still no such repository on the horizon and no one has been held accountable for that failure. No other nuclear power in the world has an operational deep geological repository either.

Fans of nuclear power, especially those promoting MSRs, tend to immerse themselves in echo-chambers of like-minded people to reinforce their deeply entrenched worldview. They tend to be masterful at excluding critical assessments such as the following. They also tend to assume that we have 20+ years to turn things around to save our asses.

Arjun Makhijani PhD: Small Reactors and Mass Production

https://www.youtube.com/watch?v=h4JFKY_R-p8

Small Modular Reactors: High Demand for Water and High Costs are Hurdles

https://www.youtube.com/watch?v=ikLpaW2mimQ&t=108s

IPCC report: ‘now or never’ if world is to stave off climate disaster

https://www.theguardian.com/environment/2022/apr/04/ipcc-report-now-or-never-if-world-stave-off-climate-disaster

UN chief: World has less than 2 years to avoid 'runaway climate change'

https://thehill.com/policy/energy-environment/406291-un-chief-the-world-has-less-than-2-years-to-avoid-runaway-climate

* This statement was made 4-years ago.

[MachDiamond]

Re: Nuclear promoters always leave out key issues

"UN chief: World has less than 2 years to avoid 'runaway climate change'"

The only thing a government body can move that fast on is voting themselves raises or programs for free stuff they can use to buy votes.

[Anonymous Coward]

Re: Nuclear promoters always leave out key issues

I'm pretty sure that by now we should have no ice at the poles, most major cities should be under water and half of humanity should be dead. However we have Al Gore and John Kerry still flying about telling us the sky is falling.

Maybe all this is just some huge con to get paid lots of money... hmmm...

We must solve the problem faster by continuing to do the things that have not solved the problem!

[Wellyboot]

Re: Nuclear promoters always leave out key issues

Fans of <insert idea/thing here>, especially those promoting <insert pet project here>, tend to immerse themselves in echo-chambers of like-minded people to reinforce their deeply entrenched world view.

That's social media algorithms for you, not long ago they used to stand on boxes in parks and find out quickly if the general population gave a flying one either way about their thoughts.

Humans evolved worrying about what might kill them in the next five minutes, not next week, never mind several years down the line. Engineers can only provide solutions to problems, it takes those in power (however they achieved it) to commit to action.

[Alan J. Wylie]

fluoride salts were incredibly corrosive to metals

The team looked into the density, viscosity, heat capacity, thermal conductivity and other properties of molten salt

In one of my previous jobs, I helped to build a viscometer for a European research institute to measure the viscosity of molten Plutonium fluoride (tetra? hexa?) at temperatures of up to 1500°C

I'm afraid it was one of the (many) companies that I've had the misfortune to be working for when it was closed down.

I still remember clearly the brilliant white light escaping through the gaps where the two halves of graphite heating chamber met.

[ArrZarr]

Going to be honest, the idea of a chemical named "Plutonium hexafluoride" makes me want to back up against the wall.

I'm no chemist, but even if I were, I don't know if I'd be at all interested in dealing with anything quite so spicy.

[Loyal Commenter]

From what I've read, if you ingested that, it would be the chemical toxicity of the plutonium that would kill you first. If you survived that, and the acute radiation poisoning, then the fluoride ions would certainly fuck you up. (The lethal dose of fluoride ions in an adult is apparently 5-10g, and they don't play nicely with bones)

I don't know if the chemical toxicity of plutonium is apocryphal, I doubt anyone has actually tested it for such.

[MachDiamond]

"I don't know if the chemical toxicity of plutonium is apocryphal, I doubt anyone has actually tested it for such."

It has been tested. One of the reasons it's so bad is that it isn't a natural element so we humans have no tolerance for it at all having never had it in the environment.

[Loyal Commenter]

Has it really? Tested for systemic toxicity in humans? Not in tissue cultures, or in animals?

I'd like to have a word with the ethics board that approved that one.

[bobbear]

You could make an interesting comparison between the old method of storing local energy in gasometers and this method of locally producing energy by this process, if it ever makes it off the drawing board and into mass production, that is. Just convert every church, (or any other ubiquitous structure such as a B&Q store), in every town to a molten salt reactor and energy problem solved!

Well... on the face of it, that is.. If you look a little deeper all nuclear power converts mass into energy, (as do non-nuclear methods), so although the authoritative NASA/GISS figures for global mean surface temperature show that global warming is often generally exaggerated & abused by various interest groups, this process is still nevertheless energy polluting, so not the ideal solution, but then given the 400% and rising increase in the human population since the turn of the 20th. century, energy pollution, (mitigated only by genuine renewables), is always going to be a problem, (among many others..), although I think Mad Vlad is working on a 'final solution' to that particular problem like a 20th. century predecessor..

Definitely an interesting local base load option, though, reducing transmission losses by localisation into the bargain as it does, and also making large scale destruction of a country's energy infrastructure that bit more difficult.

I wonder if the electrical energy system will evolve to the point where a national grid distribution system no longer exists in its present form? Interesting times.

[Evil Scot]

RFC - New El Reg Unit Of measurement

B&Q store as a size of Power station.

[Dave 126]

> all nuclear power converts mass into energy, (as do non-nuclear methods),

Non-nuclear methods such as? Burning fuels doesn't convert matter to energy. The mass of matter remains the same in a chemical reaction such as combustion, though to demonstrate that to yourself is tricky since you need to weigh gasses... Scratch that - you'd should be able to burn a fuel in a sealed container and observe no change in mass.

Please don't play around with inflammable liquids though, especially don't try to ignite them in sealed containers.

[sitta_europea]

> > all nuclear power converts mass into energy, (as do non-nuclear methods),

> Non-nuclear methods such as? Burning fuels doesn't convert matter to energy.

Yes, it does.

Not very much, but that's still the physics of it.

[Graham Dawson]

Releasing the energy stored in chemical bonds isn't, in any way, the same as converting mass to energy.

[bobbear]

The mechanism is irrelevant - you are still releasing latent energy stored in mass and that is energy polluting..

[bonkers]

Not sure about that one, they are at least in one way similar - in that the products weigh less than the reactants, as previous post noted.

And in another way, much like chemical reactions, it is the binding energies, not the components themselves, that change.

The binding energies of the daughter nuclei are fractionally higher than the fuel nucleus.

All the particles are conserved*.

So, even nuclear reactors don't exactly "convert matter (or mass) to energy" - as in the annihilation of whole particles, let alone "back to future" direct annihilation of garbage into stupendous energy.

* some of the neutron flux that sustains the chain reaction will NOT be captured in the surrounding materials and will then decay (in ~1/4 hour) into a proton, electron, neutrino - but the "hadron number" - (protons+neutrons) is the same. Think of a neutron as a bound proton+electron that is unstable in "air" - i.e. outside a nucleus.

Further caveats below, more for interest than for proof.

OK, there might be side-reactions where daughter nuclei decay through beta+ process, and the positron will annihilate with a nearby electron - that ## would## be direct conversion of mass to energy.

However, B+ decay is only favourable for neutron-light isotopes, and daughters of fission are naturally neutron-rich. I think that's the right way round, could be wrong.

If you're really picky, or just interested, yes, in beta decay, there is an antineutrino, 0.3eV or less.

It might then annihilate with a "proper" neutrino, making a direct conversion of matter to energy - but this would be in a distant galaxy, due to the vanishingly low "cross sections" - reaction probabilities - of neutrinos generally. Actually, maybe not at all, there are arguments that the neutrino is its own antiparticle, a "Majorana" particle - though this is unproven. It would mean that there is no annihilation.

[Loyal Commenter]

No it doesn't. It moves electrons from higher-energy orbitals into lower-energy ones, releasing the energy difference as heat. Add oxygen to carbon and burn it, and you end up with the same mass you started with in carbon dioxide. The nuclei involved have the same mass they started with, as do the electrons that have lost some energy.

This is the fundamental principle of how chemistry works. Shunting electrons about, and either adding or taking away energy to allow this to happen.

[Loyal Commenter]

Whoever down-voted that, be aware that you are downvoting the entire field of chemistry. Chemistry doesn't agree with your opinion.

[MachDiamond]

"Definitely an interesting local base load option, though, reducing transmission losses by localisation into the bargain as it does, and also making large scale destruction of a country's energy infrastructure that bit more difficult."

Everything in engineering is a compromise. You have to solve for the most pressing, most important problem and then see if you haven't dug yourself an even worse hole someplace else.

Lots of SMR's means lots more security and it can't be done by people that couldn't get a job at a take-away. It means much more monitoring in and around the plant to, at the very least, reassure the local population that everything is fine. It means more trained staff to run each one of these facilities. While they might be able to be remote controlled and operated from a central location, that will never be allowed on too many levels. It's too much to hope that it would ever be so safe that people would be comfortable with that.

If the main goal is to have a massively segmented electrical system as a buffer against enemy action, the problem isn't the power network. It does make sense to not have things so interconnected that a fault at a distant substation shuts down power for a large portion of the country, so it's back to finding the best compromise.

Transmission losses are a real thing, but they have to be balanced with the costs and difficulty in keeping lines very short. It could be more financially viable to have some above average losses to send power to a small community vs. installing a dedicated power plant that serves them exclusively.

[Xalran]

Original purpose

"The designs at the time ultimately proved unusable for their original purposes. "

In the 1950s and 1960s the original nuclear powerplants purpose was not to generate power... but to generate Plutonium in enough quantities to build bombs.

MSR byproducts are a PITA to use in bomb making. the U235 is contaminated by U233 and separating them cost an arm, a leg, an eye, a kidney and a lung.

and if Thorium is used in the Molten salt, Pu can't be produced in large enough quantities.

And even if the recycling ability of the MSR is small, it's good to note that they can be used to recycle long lived wastes from the pressurized water reactors into short lived ones. Any way that can reduce the amount of long lived nuclear waste is something that needs to be looked at.

[MachDiamond]

Re: Original purpose

"In the 1950s and 1960s the original nuclear powerplants purpose was not to generate power... but to generate Plutonium in enough quantities to build bombs."

It's much easier to build a reactor dedicated to producing Pu than to build one set up to produce power and have Pu as a byproduct for bombs. It was Nixon's argument against continuing funds for the MSR experiments, but Nixon was a politician, not a scientist or economist. Waste from power plants in the US aren't re-processed. Re-processing was banned at one point and after the ban was lifted, no company wanted to invest in a re-processing facility. There wasn't a market for Mox fuels and it could all be banned again wasting a huge amount of capital investment. The US likely has enough Pu for bombs to be getting on with. What was in short supply was Pu for TRG's. I think that there is capability again to make that type although it's a slow process. Perseverance and Curiosity Mars rovers are both powered by Pu fueled RTG's.

[Primus Secundus Tertius]

Scientific units please

I get so tired of promoters of power stations claiming to support so many thousands of homes. For heavens sake, can we have the real power, in watts or multiples thereof.

A fortune is spent out of my taxes on education for ordinary people. I therefore claim they should know the difference between a kilowatt, megawatt, and gigawatt; and how many homes they can support in summer (1 KW each) or winter (10KW each).

[Anonymous Coward]

Re: Scientific units please

A kilowatt runs your laptop, a megawatt charges my iPhone. For a few hours.

:)

Joking aside, I agree with you, but I suspect this is because it avoids giving exact numbers. Remember, it has to stay political. The moment someone mentions actual facts they'll take their eye off the ball and start squabbling about how that was measured.

That's too why the whole cloud thing was such a raving success. "Someone else's computer" would have invited discussions about specs which would require actual knowledge, which has about the same repelling quality to management and Sun readers than actually visible lowing radioactivity.

Sorry, as I get older I'm getting more and more realistic cynical..

[MachDiamond]

Re: Scientific units please

"I get so tired of promoters of power stations claiming to support so many thousands of homes."

The other big problem is one of whether their estimate is before or after natural gas is banned. Before or after petrol cars are banned and people need to charge an EV. Is it the number of homes in a senior community or in an area with lots of families.

[Cliffwilliams44]

But the Church will oppose it!

Nice idea, but the Church of Climatology will start a heresy campaign against it. Claiming this will bring on the end of the world.

Logic and science having nothing to do with with their religious fervor!

[Loyal Commenter]

Compare this to JRM's Mister Fusion demonstration plant...

...and here we have something that might actually appear and be useful.

[Toni the terrible]

Re: Compare this to JRM's Mister Fusion demonstration plant...

...before fusion power occurs?

[Loyal Commenter]

Re: Compare this to JRM's Mister Fusion demonstration plant...

Well, to be honest, "before fusion power occurs" is somewhere between 20 years away and never, so yes.

[MachDiamond]

Re: Compare this to JRM's Mister Fusion demonstration plant...

"Well, to be honest, "before fusion power occurs" is somewhere between 20 years away and never, so yes."

There has been fusion, but the joke is it takes an enormous amount of power to "strike the arc" and achieve fusion.

What hasn't been demonstrated is self-sustained fusion for a useful period of time. Useful being enough time to amortize the energy used in the start up. There will still be the issue of power conversion to sort out once the fusion part is running, if ever.

[Sgt_Oddball]

As a serious thought...

If this whole process can be contained within a sealed container with no moving parts, would it not be easier to move over to ceramic? Or at the very least ceramic coating to the inner surfaces to prevent fluoride corrosion.

Or is there some serious reasons as to why that wouldn't work? (yes, I know high pressures, but those could be designed around surely and would be an easier problem to resolve vs having metal dissolve due angry high temperature toothpaste?)

Most likely there's very good reasons I've not considered in the 5 minutes I pondered on this but I'd interested in what those are

[rivimey]

Re: As a serious thought...

My understanding is the reactor is not pressurized so nom not high pressures.

[Loyal Commenter]

Re: As a serious thought...

I think maybe because ceramics don't deal well with heat stresses, vibration, etc., whilst metal alloys typically do.

For example, if I handed you a metal saucepan and a ceramic bowl and told you that you had to drop one of them onto a concrete floor, which one would you drop?

[Sgt_Oddball]

Re: As a serious thought...

Not necessarily so. I mean look at Champagne bottles. They can contain impressively high pressures as for the vibrations, with no mechanical pumps, just convection currents so I'd be interested to knowwhere those vibrations would get induced. At the secondary stage maybe but then you can use a different material to transmit the heat to a vibration isolated area for the turbines generating power.

As for dropping metal pan vs ceramic bowl... I've seen cast iron shatter so not impossible. I've also seen pirex bowls bounce before. So it'd depend.

[Loyal Commenter]

Re: As a serious thought...

Champagne bottles are technically a glass, not a ceramic (the difference being that glasses are non-crystalline, IIRC), and they are also designed to be strong. Compare the thickness of the glass in a champagne bottle to the thickness of steel that would be required to contain the same pressure. Nobody launches ships by trying to smash steel flasks of champagne against them.

Cast iron can shatter, yes. Cast iron is not steel, they are chemically and mechanically very different things. And yes, sometimes glasses and ceramics survive being dropped. Not usually onto concrete though.

[hammarbtyp]

Whoops

"According to The Salt Lake Tribune"- previously known as Salt Solid Tribune

[Anonymous Coward]

I'll take any flippin nuclear on offer, frankly

No religion. Just want solid reliable dependable dispatchable cheap energy.

i.e everything that renewables don't deliver.

[Anonymous Coward]

Re: I'll take any flippin nuclear on offer, frankly

Renewables could deliver ON AVERAGE. Its just the world doesn't work very well on averages.

It is fun when the greenies claim there is no such thing as baseload. Then say you can charge your leccy car on cheap overnight electricity.

[Binraider]

Re: I'll take any flippin nuclear on offer, frankly

There is no such thing as cheap electricity because the resell price is determined by the most expensive yet (currently) unavoidable generation source. Unless you are making your own power you are tied into the price of gas by free-market economics 101.

For the record the solar system on a very average 2 bed semi was able to generate and store enough power with room left to export yesterday; on a not particularly clear autumn day. Sure, 3 months of the year I won't quite be able to generate that much. And for the other 9, I will definitely exceed that. That is all marginal demand avoided off the grid, and by definition, that is all gas not being burned to run computer/fridge/cooker/TV, or even the washing machine (provided I turn that on at the right time of day).

Cover 10% of the housing stock in the country with comparable systems and that's a good chunk of total demand sliced off, all the time for not that much expense (certainly not compared to the cost remortgaging to raise 10k to install suitable generation & storage). And a state-level intervention to get grants out there to do this is equally do-able rather than just relying on the better off proportion of the population to do the sums and decide this is a far better return on investment than most other things. Insulating properties being an even better ROI, though despite massive high profile protests "being poor" and living in "poor housing" still lacks support to get the insulation done up to good standards.

Measures to reduce how much one "consumes" from the grid are by far the best option.

Beyond that, yes, baseload "nuke" should basically be scaled to be equal to demand that never goes away. That's approx 15GW in UK; so more than double the nuke capacity we currently have in serious development. Variable demand above that level makes a lot of sense to supply with wind where possible; and gas & interconnection where not.

But supply is also subject to Free Market economics 101 so shortfalls are the subject of profiteering. This is something the EU has started making some moves on doing something about, and we could really do with doing something too.

[Anonymous Coward]

Re: I'll take any flippin nuclear on offer, frankly

Its not 'free market economics 101' tying the wholesale cost to the cost of the last dispatched power source (usually gas in the UK). It is by design to keep the wholesale cost high. The renewable generators bid low to get the contract to build knowing full well that any dip will be picked up by gas and that they will get the gas wholesale price.

A free market system would be the generators get paid individually rather than though the current collective wholesale market.

Remember a lot of the fossil fuel companies are heavily invested in renewables as it is a total cash cow.

[Binraider]

Re: I'll take any flippin nuclear on offer, frankly

Pretty sure we have just argued for the same point in different terms.

In a generators paid individually world; your contract for supply is with the windmill or gas burner. Both would still tend to the last-dispatched cost, because why would you not charge as much as possible?

Competition only reduces prices where there is surplus, free market economics 101.

The wholesale market could be designed to limit resale price by generation cost; those in power and shares have no desire to do so. And so the problem continues.

[GaryB_]

Mobile, modular

Imagine a vehicle that runs for years — boat, mining, in air Satellite. I’m not there do use it’s just as a heat source especially for desalination.

[Fruit and Nutcase]

BYU

Almost pre-destined that BYU are working on Molten Salt reactors, Utah/Salt lake country

[ShortStuff]

Here we go again !!

This technology has been promised for decades and never goes anywhere. It has either already been developed and used within the military, or is bogus and used only to extract money from taxpayer funded government grants.