Nuclear Physicist Explains - What are Thorium Reactors?

Nuclear Physicist Explains - What are Thorium Reactors?
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Read more about the Molten Salt Reactor Experiment at ORNL: www.ornl.gov/molten-salt-reac...
In this video, I explain Thorium Reactors from the perspective of a nuclear physicist. I go through Thorium Reactors and what they are and compare them to current uranium fuelled nuclear reactors.
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[@YourFriendlyNuclearPhysicist]

This is the most advanced video I’ve made so far, I tried my best to explain it as simple as I could. Let me know what you think! Are you guys team thorium or team uranium?☢️👩🏽‍🔬

[@marvintpandroid2213]

Team what has been shown to work on scale, at this point I am more in favor of Uranium.

[@bart416]

How about team accelerator driven sub-critical reactors? 😁😁

[@Evghenios79]

Team Both and also Team Fusion

[@SonnyKnutson]

Thorium for sure! But Uranium is still needed to start the reaction I think? ^^

[@kimmogensen4888]

Uranium, until technology is better, and invest in both but mostly in Uranium 10/1. But pulefuration is not always problem, i think, Sweden has uranium reactors but no nuclear weapons, not because they can't build nuclear weapons, but don't want it, or I reckon they can build one.... As a neighbor I wouldn't be concerned if Sweden built a thorium Reactors.

[@spidalack]

Finally, a proper explanation that isn't just hype. You made it quite clear and understandable. Thank you very much

[@FlorinArjocu]

+1 on that. I've seen a few clips about this, but clearly they did not understand the process and implications.

[@mightym]

Hydrogen combustion will literally make all this talk about nuclear redundant in 5-10 years

[@FlorinArjocu]

@@mightym Hidrogen plane combustion? It is not that clean. It burns at higher temperatures and it creates much more nitrogen oxides. Might be an intermediary solution until we have completely clean transportation.

[@mightym]

@@FlorinArjocu how do you get nitrogen oxide out of 2H2 + O2?

[@FlorinArjocu]

@@mightym That is very simple. You do not use pure oxygen, but you use air. Air is about 80% nitrogen.

[@sevilnatas]

The thing that I heard and sounded attractive to me, was the idea that Thorium is already being mined in great quantity but is considered tailings to other mining processes. Specifically, rare earth element mining supposedly produces a lot of Thorium waste, so that would have the advantage of creating a use for something we are currently "throwing away" right now. I am no expert, so what I have heard may be typical internet FUD, but if it is true, it does add to the benefits of Thorium.

[@KOz1caa]

This is true Google is great.

[@PeterHowell]

Additionally, the disposal of thorium is a big part of why it's very hard to get rare earth mining approved in Western countries. Being able to turn a waste product into a product would go a long way toward opening new sources for the rare earth elements we need for expanding renewables. The irony is that using thorium could hasten the transition to renewables.

[@tarmaque]

Thank you for your unfiltered opinion on the subject that isn't poisoned by unbridled optimism. You clearly have a more informed background on the subject and the ability to reason about the benefits as opposed to the disadvantages. Thank you again.

[@Joe-ho6fo]

I’ve heard a lot about the advantages of thorium. This was a well balanced and unbiased presentation of the pros and cons.

[@tonyrmathis]

Did she skip over the safety aspects of did I just miss it? Not being able to sustain run away chain reactions that lead to meltdowns is a major advantage in my opinion.

[@wezleyjackson9918]

@tonyrmathis Yeah and having cesium rods that need to be in safe storage with no earthquakes for 1000s of years could be another advantage. Better to just completely ignore the benefits of disposing of such waste with breeder reactors (LFTR Thorium) in favor of going with what you know works. (Apologies to other readers that I emit sarcasm in response to untruthful stupidity). Tony and I got triggered.

[@tonyrmathis]

@@wezleyjackson9918 I find there's two types of people who oppose thorium reactors. Those with a vested interest in other designs and members of the eco-cult who don't consider humans to be part of nature. One doesn't want change because it means less money and more work for them. The other that just hates people and wants fewer of them.

[@peterclarke3020]

Kind of - though she did miss a few major points - and failed to properly mention the LFTR’s advantages. See my other note about 7 points missed.

[@peterclarke3020]

@@tonyrmathisYour right, she missed several major points about the advantages of LFTR. No mention of the higher thermodynamic efficiency from operating at 800 deg C for instance. No mention of ‘freeze plugs’. She did mention ‘negative coefficient’ of ‘operation’ - but failed to explain it. (Thorium reactors are passively safe - because if they start to overheat, the liquid expands, reducing the reaction rate, so it cools down by itself). That was tested out at oak-ridge, when it was left running for several days, without any active controls being used.

[@toddkes5890]

Chapters: 0:32 - What is a Thorium Reactor 1:43 - How is a Thorium Reactor different from Uranium Reactor 3:06 - Fuel Abundance (amount of uranium and thorium in Earth crust vs oceans) 4:36 - Safety (Proliferation & temperature) 7:28 - Economics (enrichment vs amount used in a reactor, fuel manufacturing costs, and refueling operations) 10:45 - Efficiency (higher efficiency, but neutron speed issues) 12:35 - Waste (no trans-uranic wastes, lower radioactivity, short-term toxicity, solid vs liquid waste, chemical problems) 14:52 - Proliferation (hard to steal, U-233 proliferation) 18:49 - Current Status (little experience with running or dealing with waste)

[@mirrorflame1988]

Thank you for the time stamps and short notes. It is really helpful!

[@marcwinkler]

Where are Thorium reactors ... nowhere to be found. Why ... Thorium is not fissible.

[@toddkes5890]

@@marcwinkler Tell me you didn't watch the video without saying you didn't watch the video

[@paulsmith3921]

@@marcwinkler There is a test one being built in China.

[@marcwinkler]

@@paulsmith3921 Let them do the research, good luck!

[@bleachie]

I learned so much about Thorium reactors! I’ve heard about them before, but people acted like they had no downsides. I really appreciate all the work you put into making this video!

[@YourFriendlyNuclearPhysicist]

Thank you so much I’m so glad you found it informative ☢️👩🏽‍🔬

[@SonnyKnutson]

Ofcourse they have downsides. But they have soooo many safety upsides it's insane. The biggest being that it does NOT use high pressure water in the reactor which is the biggest cause of disasters from the current designs. Because high pressure water flashes to steam and creates a hydrogen explosion. Hot gases goes UP into the atmosphere. LFTR's doesn't use any high pressure anything. If there is an accident where the molten salt for some reason would leak out of the reactor. The contamination is contained locally and the salt freezes to a solid salt. Making the contamination very easy to manage. They are also very much cheaper because they don't need a huge containment building around them because of the same reason. The designs I've seen also have a drain tank with a freeze plug. Fans using power from the reactor to blow cold air on a pipe to a drain tank. Freezing the salt to a solid state creating this plug. In case of a loss of power the fans stops cooling the pipe and the hot salt melts the solid salt in the pipe. Then it all drains to a draintank. This tank is prepared with a lot of surface area and neutron absorbing materials. Meaning the whole reaction stops and the salt freezes solid as it cools down.

[@lmaoroflcopter]

@@SonnyKnutson hey dude there's a video above your comment you may want to watch.

[@cezarcatalin1406]

@@YourFriendlyNuclearPhysicist Hey, how about liquid metal cooled fast neutron reactors? By using an eutectic mixture of tin and gallium that melts at 21C but boils at over 2000C we can make cores out of solid but thin thorium-uranium metal alloy disks stacked on rods and placed in a honeycomb shape. The volatile materials escape through the tiny spaces between the disks and bubble to the top while the rest mostly stay on the rods. Given a large enough core that can overcome via the square-cube law the neutron deficit due to escaping neutrons, it would actually be a viable way of producing power with minimal waste.

[@wernerviehhauser94]

@@SonnyKnutson yeah, well, no. Creating hydrogen from water does not require steam or pressurized systems. Radiodissociation can happen at room temperatur. Molten solt reactors generate Tritium, an Hydrogen isotope, during STANDARD operation, which has to be dealt with. Some "salts", like UF6, are gases even at room temperature. They can be generated during standard operation, too. Unexpected contaminations like these have been found in filters of test reactors, and the engineers were "surprised", to say the least. You are not as proficiently informed as you think you are.

[@ASMM1981EGY]

One of the best scientific "LECTURES" I've ever heard on the internet. Thanks from EGYPT

[@farmergiles1065]

Very clear summary and explanation of the pros, cons, and trade-offs. Many thanks! I have not looked into thorium reactors much before. Excellent introduction.

[@mrstevecox7]

Good video: I'm team Thorium! 1) I think the proliferation issue is overplayed: we have the same issues (if not worse) when it comes to Uranium. Nuclear fuels and processes will always need security. The U233 stage of thorium cycle does not need a specific place for storage: it will be in a dynamic salt solution and will not need to be separated out and cooled off. 2) Availability: only if we use up all available Thorium then we will need to develop (really expensive) undersea mining of Uranium! But the existing Thorium in India, China and in the tailings of rare earth mining will last for kiloyears even if *all* energy production is diverted to Thorium plants. This is not a significant problem 3) Tech difficulties: if 10% of fusion research funding were diverted to Thorium tech solutions (corrosion issues and pumps, mainly) then there would be working reactors by the end of 2023 (not 2050 as the projected date for anything useful to come out of ITER!). 4) Storage of waste: ditto re technical issues. The slightly larger front end costs of Thorium waste are heavily outweighed by the long term issues of conventional storage of the Uranium cycle (and these do not disappear even with reuse of Uranium waste as a fuel in a MSR). 5) In conclusion, Thorium needs to be front and centre right now, not kept on the shelf in case Uranium doesn't work out..Many thanks for a great run-down!

[@JD96893]

i agree, thorium MSRs are probably the fastest way for us to get off fossil fuels. I don't think Elina likes the thorium LFTR reactor design. I think we are seeing a sunken cost fallacy here, which is literally why research was stopped in the 70's on MSRs. The thorium abundance part failed to mention that we need something like 35 times less thorium than uranium to produce the same energy in heat. MSR reactors can also convert that energy into electricity more efficiently. So yeah to hell with uranium, we would never need to get it off the ocean floor. MSR reactors need more research done, they are superior in many ways to other reactor designs, its not just thorium reactors that need research done and need to be built. LFTRs combine the best of both.

[@robertweekes5783]

Also a byproduct of U233 is a gamma emitter, U232, which would make a bomb easy to detect remotely with instruments. There are also methods to reduce proliferation risks that have been addressed before, for example running a design with “denatured” solution including U232

[@kayakMike1000]

@Robert Weekes you sour milk the milk, so it doesn't taste so good... No one wants to have that around..

[@theotherguy982]

For your point 1, how do you account for the Protactinium, which was the stage that Elina specifically called out as the proliferation danger? That's what needs to be stored separately until decayed into U233, during which time weapons-grade nuclear material is increasingly available outside of the reactor, a situation not found at all in a typical uranium-based reactor.

[@mrstevecox7]

@@theotherguy982 The decay from Pa to U233 only takes a week or so, thus there needs to be no "separate storage". It can be kept in dynamic salt solution. There will be no difference in the security measures between Th and U plants. all fissile material needs the same precautions. Who are you getting your information about "separate storage" from?

[@autarchex]

My favorite little feature of the LFTR prototype was possibly its simplest aspect - if there is any kind of power loss or need to shut down, the cooling mechanism keeping the drain outlet solid stops, the plug melts, and the reactor empties itself into the storage / reheater tank where the liquid salt freezes until you are ready to start it up again.

[@christopherleubner6633]

Easily done as well, just make the tank a donut shaped reservoir

[@hewdelfewijfe]

This is a common misconception. There are two main problems to solve for reactor safety in any reactor design: stopping fission, and fission product decay heat removal. The drain plug does nothing to help with fission product decay heat removal. The AP-1000, a solid fueled conventional reactor, uses the same strategy for decay heat removal - have a big tank of water on standby with pipes near the core so that gravity and heat differences drive a natural circulation to move heat from the core to the outside air without pumps. In contrast, the drain plug idea is very useful to move the fuel to a new geometric configuration and location to ensure that recriticality is impossible.

[@tonyrmathis]

@@hewdelfewijfe Your 'common misconception' was used for 2 years in Oakridge over 50 years ago. The reactor shut down every weekend when scientist went home. Shut down in hours not months like other reactors. Then restarted every Monday. The same cooling pipes used for the heat exchanger could be used to remove waste heat and even if they weren't the heat isn't so high that it's a problem. The reaction stops. The fuel solidifies. The heat dissipates. Nothing melts down. Too hot no fission. Too cold solidifies. It's completely self-regulating.

[@hewdelfewijfe]

@@tonyrmathis I thought I responded to this already. Guess not. Trying again. I'm a bigger pro nuclear advocate than you are, and I know more about nuclear stuff than you do, so shut up and listen. That old experiment was a low power reactor. I do not know what things they had, if any, to remove the decay heat. Maybe all it needed was passive air cooling. When you scale that up to a commercial reactor, you're going to have much higher power densities, and then passive air cooling is not enough. It does not matter how you achieve fission - the fission products still produce the same amount of heat. The drain plug is primarily about solving the problem of recriticality by moving the fuel to a new geometric configuration. It does nothing to change the amount of fission product decay heat. You still need to move that heat out of the core. Now, the drug plug might help by moving the fuel (and fission products) to a new location that has better cooling. That could be part of a design. However, again, the drain plug by itself does not remove the need for cooling and removing fission product decay heat.

[@tonyrmathis]

@@hewdelfewijfe "When you scale that up to a commercial reactor, you're going to have much higher power densities, and then passive air cooling is not enough." A scaled up reactor would ALREADY have something other than passive air cooling. Are you really suggesting that it wouldn't also be used to cool the drain pan? "The drain plug is primarily about solving the problem of recriticality by moving the fuel to a new geometric configuration." It's not just the geometry. It gets the fuel away from the graphite moderator. My point still stands. If air cooling was enough to handle the decay heat on the Oakridge reactor then decay heat isn't a serious concern. REGARDLESS OF THE SIZE OF THE REACTOR! In fact one design incorporates storing the fuel until it decays to the proper element for burning then reintroducing it to the reactor. Molten Salt Reactors won't run at higher temperatures. The reaction is not sustainable at high temperatures. It's why they're inherently safe. Scale doesn't matter. In fact part of the problem with using them for power generation is their temperatures run so much lower that steam isn't the best choice for the power turbines. You're mixing the physics of the uranium chain with the thorium chain. Decay heat doesn't continue to build until it melts everything around it in the thorium chain. The higher the temp goes the less decay occurs. And without a moderator even at the proper temperature the reaction doesn't proceed.

[@alamagordoingordo3047]

Great content, very clear and concise and exhaustive for a difficult topic, best thorium reactor video i have seen.

[@TheDocValerian]

Thank you for explaining this in a very understandable and hype-free format that focuses on what we currently actually know and also what the drawbacks are.

[@ahettinger525]

I've always liked everything I've heard about thorium reactors (admittedly, mostly due to the safety advantages of molten salt designed compared to our more common PWR designs), but you pointed out concerns I've not heard discussed before. Thank you!

[@danilooliveira6580]

the thing is, modern reactors are already INCREDIBLY safe, of course being virtually impossible to catastrophically fail is better than incredibly safe. but given all the other problems, the safety ends up being not as interesting.

[@JohnW118]

@@danilooliveira6580 No, not so "incredibly safe". High pressure water Uranium reactors will ALWAYS be inherently dangerous, prone to runaway meltdown and steam explosion. Three disastrous and long-lasting failures already across the world (plus two more in 1957). And then there is the easily retrieved Plutonium...far more dangerous than U233.

[@m4ktub1st]

@@danilooliveira6580 Except for the cost. Current designs are safe because a lot is invested in construction. If new designs are safe by default then the cost of construction could be reduced. For example, MSRs operate at low pressure and can do without those costly containment buildings.

[@dongleseon8785]

@@m4ktub1st No, MSR operates with extremely reactive coolant with high temperature which means it's the opposite of "safe by default" thus the safety measures are probably more expensive than PWR. MSR is only safe from total melt down. It has higher risk of other accident. Also, high gamma radiation means more embrittlement of core material = More frequent maintenance & shorter life span

[@m4ktub1st]

​@@dongleseon8785 Thank you. I was indeed assuming most of the cost was to protect from a total melt down, the most catastrophic scenario.

[@TCampbell001]

Great video Elina! I've been reading about thorium as a fuel source for years, but you gave a thorough explanation of the process. I always thought the waste produced was minimal ( compared to LWR) and could be recycled.

[@davidreznick9902]

I think CANDU reactors are the way to go. They can run on unrefined uranium, thorium, or even spent fuel. They can refuel without shutting down. They also have been used for decades and are a known, safe design.

[@nathanwilson7499]

Once-through fuel cycles are nuclear training wheels; for million year sustainability we need breeders (Th or U238) and reprocessing. Yes Candus can breed using thorium, but they need more frequent reprocessing compared to fast breeders or LWRs, which drives up cost. Liquid fuel makes reprocessing cheaper, so it's that or fast breeders (with or without LWRs).

[@grahambennett8151]

@@nathanwilson7499 Can you build them cruise-missile-proof?

[@juandiegosol9981]

Great and clear video, thanks for the explanation! I'm just starting to learn about Thorium and this definitely got me to start in the right track

[@HeathInHeath]

Thank you for the clear explanation of the issues involved in the consideration of thorium reactors for nuclear energy production. I have never heard such a comprehensive explanation and found it quite enlightening.

[@JetDom767]

The thing with thorium reactors and uranium there will always be advantages and disadvantages. But honestly I agree we need something where the reactor deals with its own waste, I would also be open to the idea of fast breeder reactors.

[@marcwinkler]

google 6 150 000 results for history of past experiences like superphenix tricky staff

[@yulfine1688]

Waste hansn't been an issue since the late 60s when dry casks were being utilized and not a sinlge leak has ever happened from a dry cask. Also you can bury them similar to how the planet handles its own versions of nuclear waste on site and it wouldn't be harmful or dangerous to anyone and you could easily do it for the life of the entire plant.

[@steveofthewildnorth7493]

Excellent video! My late father-in-law worked on the molten salt reactor experiment during his career at ORNL. He'd have loved your explanation.

[@anteparts]

Amazing, I love it ! Thank you for the perfect sum of MSR and Thorium explanation. Will look for new episodes

[@cfoote416]

Thank you for all the hard work and such a great explanation.

[@larsegholmfischmann6594]

Thank you so much for making this! I really learned a lot from it, found considerations I didn't realize was there. I'm actually less optimistic about thorium now than I was before, mostly because some of the stories I heard was apparently wildly exhaggerated. Top notch Elina :)

[@JehuMcSpooran]

Great explanation, Elina. There were a few things in there that has not been brought up and explained in other videos on the subject. I wasn't aware of Uranium 233 and how it is weapons grade. I do agree that finding a way to burn our old nuclear waste is a priority. Waste is a resource not yet exploited.

[@robertweekes5783]

Burning waste can be done most easily in an MSR, because it’s much easier to do chemistry with liquids than solids 🧪

[@outerspaceisalie]

There are already some ways to burn waste, but it has so many downsides and is so expensive that we dont really do it.

[@ObiWahn68]

You haven't heard about U-233 being weapons grade because it isn't! No country has developed nuclear bombs based on U-233 for a reason. Impurities of U-232 as low as 50 ppm are enough to make it unusable for nuclear bombs and the impurity in a Thorium based reactor will always be much higher than that.

[@outerspaceisalie]

@@ObiWahn68 but u-233 reactors do produce weapons grade material. 😂

[@ObiWahn68]

@@outerspaceisalieNo, they don't. What kind of material are you talking about? As I explained the U-233 itself isn't weapons grade due to the impurities and they produce neither U-235 nor Pu-239. 🙄

[@QingWeiSanguine]

This was very interesting :) I did not know about the liquid salt state of the thorium in these reactors. Thank you so much for the great explaination of how this works :)

[@wnhulsey3]

This scientist is highly capable and a delight from which to learn. Thanks so much for this excellent work!

[@alexluthiger731]

She knows and understands what she is talking about. A rare phenomenon these days. 🍷🌁

[@callthemall]

Can you do a video explaining the difference between generation 1, 2, 3, and generation 4 reactors? Excellent videos I have watched every single one!

[@csdn4483]

Mostly it's built in safety measures. One example I know of with a Gen 3 PWR design was using borated water in a "pool" at the bottom of the reactor vessel that due to density differences would stay in the "pool" while the regular water was traveling through the core. However, if the regular water started to boil off, the borated water would naturally move upward from the "pool" to cover the core and shutdown the reaction. Gen 3+ reactors typically require an act of sabotage, by removing the inherent safety systems, to cause a meltdown. Typically the worst accident you'll ever see with Gen 3+ reactor is a LOCA (loss of coolant accident) which on the scale of accidents is a 4 (TMI was a 5, Chernobyl and Fukushima were 7, the highest, Windscale was a 6). Accidents scale 1 to 4 are always contained within a small area whereas 5 can get into the environment and 6+ has environmental impact.

[@HexaSquirrel]

@@csdn4483 Also, Gen 4 contain large improvements in efficiency: from Gen 3/3+ ~33%; Gen 4 ~50% efficient.

[@-_-fedde]

Love your videos, they are very helpfully. I have a test about partial physics, and your content helps me be motivated about the subject and helps to learn.

[@brynduffy]

Very good presentation! The best I've heard so far over the last several years.

[@woodrowbarstad4549]

amazingly clear, concise and through presentation. logical analysis of pros and cons. Storage and proliferation are obviously of relevant concern.. thank you

[@michalchik]

I think really what we should be focusing on in this technology is the molten salt aspect of it. The incredible efficiency largely comes from that aspect of the technology. Thorium is great for a lot of reasons and it is probably our preferred fuel but what's wonderful about molten salt is that we can make it much more efficient and separate out waste products very easily as well as building intrinsic safety in the geometry of the nuclear core through thermal expansion and the drainage basins.

[@philplasma]

I had heard of Thorium and molten salt in terms of reactors, but never so detailed and well explained. Thank you. Real Engineering just covered Helion's fusion reactor, I'd be curious to see your reaction to it.

[@lukegriffith2590]

:)

[@jokermtb]

Yes- saw the Helion news too. Looks interesting

[@tonyrun5802]

I may suggest this video, which treats the matter in an even more in-depth way: kzbin.info/www/bejne/fmfQmapjeLOrl6c

[@jovianr900]

@@Joe-by8jh Did you mean fusion reactor? Your comment makes no sense either way.

[@gabbes23]

@@Joe-by8jh ... I'm pretty sure the thorium reactor at Oakridge was connected to a thermal radiator because there was no generator connected to the heat exchanger. It pumped out a bunch of thermal energy that had to be dissipated. It isn't really like fusion where you need to pump in loads of electricity... Once the fission reaction is happening all you have to keep up to it is more thorium (except for running the pumps and other machinery I suppose). My biggest gripe about the Oakridge reactor was that uranium was mostly used in it to test the design.. A lot of thorium was turned into U233, but they were shut down for political (supposedly budgetary) reasons before they could use much of it. Something like 500t of the U233 is currently being destroyed because it was never allowed to be used (a significant effort is underway to save that U233). Also because of the way they were shut down, the reactor and equipment were never cleaned out before the fuel froze inside. They still have to clean that up somewhere I believe. The concept of the experimental thorium reactor requiring more power than it made isn't really a logical concept for fission power in general I don't think...? Unless you have statistics on how much power was required..? I think the thermal output at the radiator was about 7MW..

[@rossheikkila6959]

I love your easy explanation to a complicated subject. As a Refrigeration Mechanic I may have enjoyed more advanced learning in Physics. Great work! Calgary, Canada

[@Bruvva_Wu]

Well said! Answered alot of my questions. Thank you!

[@JK-rv9tp]

Nobody seems to have ever heard of the Canadian heavy water reactor CANDU, that's been around since the 70s. From what I can tell it's a unique design. Where I live, CANDU reactors provide 2/3rds of our electricity. They run on natural uranium with deuterium as the moderator, and can be refueled while running, with the fuel loaded horizontally instead of vertically. Control rods are suspended electromagnetically for passive shutdown with power failure.

[@eboyce24]

I only recently started looking into nuclear, and CANDU was the first type that popped up while hunting for PHWR details. Seemed like there was a lot of development with some issues with politics and execution, and it was hard to tell whether their newer models just aren't being implemented due to past failures or whether other models are more attractive--or some combination of the two. To me, not knowing much about it, the designs sound pretty good for small-scale, potentially modular designs. Like some other commenters i'd definitely like to hear Elina's take on recent or not-so-recent developments for CANDU-6 derivatives and CANDU-9, and whether there is a future for the models despite what appears to be a lack of significant interest. The US hasn't seemed to have been a target market, and i'm wondering whether we just have better designs already that i haven't seen yet.

[@JK-rv9tp]

@@eboyce24 CANDU was developed b/c Canada was a tier 1 nuclear power that participated in the Manhattan Project, but didn't have the manufacturing base to build large single vessel designs, and wanted to be free of the enrichment requirement. Deuterium allows use of natural uranium, and the pressure tube design allowed easy manufacture of the bits. The downside of HW is more space is required btwn fuel bundles so the core is larger overall than an equivalent light water reactor. US and other powers were uninterested b/c they needed the enrichment capability anyway for weapons. However, another bonus is you can burn spent LW reactor fuel in a CANDU. S Korea has one of each and does exactly that.

[@nirmalkrish4113]

Very underrated channel; thank you very much for this beautiful video; this should be shown in all secondary schools from grades 6 and up. Keep up the good work, loving the feeds.

[@LFTRnow]

Elina, I've been studying LFTR reactors for over 15 years and I think you've made a good video here, but wanted to add some points: 1. (Abundance), everything you said is correct, however, thorium is also available as 6%+ concentrations in Monazite sands, which are the sands used for extraction of rare-earths (the materials we use for high technology and renewables today). The thorium is currently considered waste, and due to being (mildly) radioactive, is considered a disposal hazard. When thorium reactors take off properly, the fuel will basically be free - the waste from our rare earth mining. One other point, when considering land extraction, thorium is more abundant across many countries compared to uranium. This means you don't need to have access to the ocean or to be one of the "lucky" countries that have or don't have uranium. Thorium is basically everywhere, but especially in the rare-earths (particularly the "heavy" rare earths). Keep in mind also we have a LOT of U238 (depleted uranium) lying around, so this is another great source of non-fissile, ie FERTILE fuel for reactors, just like Th232 is a fertile fuel. 2. (Safety), As you know, reactors in general are very safe, you need only compare deaths/TWh the "deathprint". You also mentioned about the fuel from a LFTR potentially freezing in the reactor during power loss. This is unlikely due to an additional automatic safety feature known as the freeze or salt plug. In the bottom of the tank there is a pipe that leads to another tank which is designed to radiate as much heat as possible and can be a storage tank. A fan blowing on the salt plug keeps it solid. If power is lost, the fan loses power and the salt will melt due to losing its cooling, and the reactor salt drains into the tank below it. Note this is all done without human or computer intervention. 3. (Economics), all very well done in your video. I'd add that if you assume 6% thorium (in monazite sand) and you assume you can extract and consume all of that thorium in a LFTR, then a soda can of sand has the energy equivalence of 40,000 gal of gasoline. Google Monazite sand (and thorium) as well as the energy density of thorium and gasoline to check my math. To me, this means thorium (and LFTRs) make oil obsolete or archaic. Liquid fuels could easily be made from the reactor heat. 4. (Efficiency), again all well done. I'd point out that the U233 would make an excellent start-up material for more reactors. Once you have a proper LFTR running, you can extract some of the fuel as startup for other reactors. U233 also becomes Ac225 from natural decay, and this is a cancer treatment called "MATT - Medical Actinium Theraputic Treatment". Also the U233 can eventually become Pu238 which is used to power RTGs for space exploration. You need a special reactor for making RTG fuel, as standard reactors with U238 contaminate it with too much Pu239 and other heavier isotopes. 5. (Waste), the fission of U233 creates a similar mix of isotopes to U235 (and Pu239) fission, with some ratios changed a bit. These fission products decay comparatively quickly (you are correct about the hundreds of years figure). Once you have isolated the fission products then you have a more concentrated (but less volume) of waste and much of this waste can be recycled, which is not easily true for the solid fuel reactors of today. Since the fuel is a liquid you can chemically pull out the elements of interest, and many of these isotopes are valuable. There is no reason to assume that alternatives to water ponds would be required to house the waste of a LFTR as the same fission products are made. However, there will likely need to be some interm cooling for the first day or week after the hottest (thermally and radioactive) materials are extracted. They will rapidly solidify however, or could be reacted with other elements to make solids of the element of interest for storage in the spent fuel pool. 6. (Proliferation) The U233-based bomb does work, but it still is difficult to deal with. The U232 produced along with the U233 is highly radioactive and thus easy to detect. It would also cause havoc with the bomb makers as well as any electronics. Finally, one could make this argument about a lot of reactors. Used improperly, they can be used to breed materials into bomb materials. However, it is easier to enrich U235 than it is to go through the diversion of fuel from reactors.

[@LFTRnow]

6a (Proliferation). Robert Hargreaves wrote an excellent response to the issue regarding proliferation from U233 and LFTRs. This is his reply which you can read in "New Scientist". Drs. Hargraves and Moir respond: A commercial reactor will make just enough uranium to sustain power generation. Diverting any would stop the reactor, alerting authorities to a breach. Certainly terrorists could not steal U-233 dissolved in a molten salt solution along with lethally radioactive fission products inside a sealed reactor. International Atomic Energy Agency (IAEA) safeguards would require security, accounting of all nuclear materials, surveillance and intrusive inspections. It is conceivable that a nation or revolutionary group might expel IAEA observers, stop a liquid-fluoride thorium reactor (LFTR) and attempt to remove U-233. Skilled engineers would need to modify the radioactive reactor’s fluorination equipment to separate uranium from the fuel salt. U-233 produced in a LFTR is a poor choice for nuclear weapons because the neutrons that produce U-233 also produce 0.13 percent contaminating U-232, whose decay products emit 2.6 mega-electron volt, penetrating gamma radiation. That would be hazardous to weapons builders and obvious to detection monitors. The U-232 decays via a cascade of elements to thallium, which emits the radiation. A year after U-233 separation, a weapons worker one meter from a subcritical 5-kilogram sphere would receive a radiation dose of 4,200 millirems per hour, compared to 0.3 millirems per hour from plutonium. Death becomes probable after 72 hours of exposure. After 10 years, this radiation triples. U-232 cannot be removed chemically; centrifuge separation would make the equipment too radioactive to maintain. Conceivably, nuclear experts might try to devise chemistry to remove the intermediate elements of the U-232 decay chain before thallium is formed. But at-risk nations could be limited to using a LFTR variant with no chemical-processing capability. Deploying LFTRs will decrease, not increase, risks of nuclear weapons proliferation. Kickstarting LFTRs with plutonium can consume existing stocks of that weapons-capable material. Using thorium fuel reduces the need for U-235 enrichment plants, which can make weapons material as well as power reactor fuel. This energy source is cheaper than coal, can increase prosperity and can reduce the potential for wars over resource competition.

[@heyRex]

👍

[@remibegaud1896]

Do you see any major dowside to this type of reactor ?

[@ChemEDan]

Username checks out :)

[@remibegaud1896]

@@ChemEDan you're right

[@adamjeayes6525]

Excellent video - I learnt more from this than several previous videos about Thorium reactors, particularly about the pros and cons. Would love to see a detailed video about the type of reactors that can use up existing nuclear waste, as you alluded to towards the end. I've heard about these a while back, but the detail was sparse, the pros & cons not really examined from a balanced point of view, and now I can't even find anything of note on the subject - but I think you'd do a great job explaining them! It seems like an absolutely obvious way forward, so why aren't we developing reactors that can burn up existing waste & turn it into clean electricity? Also, how efficient would these waste-burning types be - what's left at the end of the process exactly?

[@dporangecounty]

I’m a long time viewer and supporter of Subine and only today discovered your channel. Loved your reaction to her video and look forward to viewing more of your content.

[@acephas3]

Honestly, molten salts seem to have so many applications over the last 20 years. Learning about Thorium reactors in a balanced, nuanced way is why I love this channel.

[@HootMaRoot]

I think the main reason there is lots of talk about molten salt reactors and batteries is we now have materials that will not corrode as easily with different types of molten salts

[@SonnyKnutson]

@@HootMaRoot Yes, still more high temperature corrotion resistant materials would be needed but a lot of it already exists. Plastic composites that can take nearly 2000 degrees celcius.

[@dennisgarber]

@@HootMaRoot I think a good section of the video should have been devoted to materials now available that can make lftr a reality.

[@ipissed]

@@HootMaRoot "As easily" are the key words. There is no known material that can handle molten salt. It's like liquid sandpaper. It will deteriorate anything eventually. The only answer is to build two power plants and constantly rotate one while the other is being rebuilt. Not worth it.

[@fanOmry]

@@ipissed Why? Just make sure each lasts long enough to payback and more the investment, and have enough spare parts so they can be built fast enough. Done.

[@kevininpualsphotoclass]

This is more in-depth than reaction videos, I love it. Would You consider expend this into a series on Generation IV Nuclear Reactors?

[@rgsteele290]

Nicely don,e you answered all my questions about Thorium reactors. I agree completely with your conclusions.

[@adamcheney3421]

Awesome video, thank you; I thought the information on proliferation risks was particularly enlightening. Any chance you could do a similar breakdown on pebble bed reactors? They seemed to be all the rage a few years ago, bit it's all gone quiet ..

[@lamina566]

First, the reactors used in France use Plutonium as a fuel source which is highly usable to make nuclear bombs. Second, the US DOE designed and implemented a Thorium reactor in the 1960's and the reactor was operated for over 5 years without an incident. The reason why the project was shut down was because DOD had decided that light water reactors were to be used to power submarines and other military platforms in the late 1960's and they didn't want this initiative to detract from the DOD decision.

[@JoseFernandez-yz1sf]

LFTRs has graphite in its core to moderate speed of neutrons, so the graphite deforms under neutronic radiation and needs to be replaced once in a while, this increases the operational cost, however there are solutions to mitigate this cost. Another problem is leaks of tritium, also could be mitigated with some engineering. The Hastelloy N was invented in ORNL during MSRE and according to some reports I have read from MSRE the corrosion found was tiny or non-existing.

[@chapter4travels]

The problem with Hastelloy N is that it was never nuclear-certified. In the US that certification would take 20 years and a few billion dollars because the NRC hates nuclear. Instead, they are just replacing (refurbishing) the reactor vessel every 6-9 years as you said. From the numbers I've seen, this is still very economical.

[@CapitaineNautilus]

Thanks for providing such an excellent presentation.

[@416dl]

An technical and well balanced look at reactors, or any energy source, is a rare thing as it seems as if there is a tug of war over the future energy market as it continues to grow. Thank you for this.

[@langdalepaul]

I think you would get a balanced view from any nuclear scientist.

[@peterfitzpatrick7032]

@@langdalepaul ... just like we got a balanced view about the COVID "vax" from any doctor ? Hah !! 😂

[@niemerow1953]

This is the best video I've seen of the pros and cons of thorium reactors. Thank you!!

[@YourFriendlyNuclearPhysicist]

Thank you so much I’m glad you appreciate it 👩🏽‍🔬☢️

[@michaelwebber4033]

No one else I've ever watched talking about thorium has ever explained the proliferation issues with it. Thank you that was fantastic

[@pavelevtushenko9006]

Thank you, Elina, very clear explanation and nice video.

[@holden5478]

Excellent video! I was arguing with my nuclear engineering friend of mine (I'm an electrical engineer) over thorium reactors a few years ago. He was very much against adopting it on scale based on practicality.

[@YourFriendlyNuclearPhysicist]

Thank you I’m so glad you liked it 👩🏽‍🔬☢️

[@goiterlanternbase]

Other than her, he had actually a grasp to reality and not just so flashy promotions from a bunch of tech scammer's😏

[@RobBCactive]

My experience of doing the requirements analysis of the control system for a nuclear power station project has made me a fan of renewables. Basically the interaction between government & large private interests make megaprojects with large political & economic implications very traumatic.

[@goiterlanternbase]

@@RobBCactive 🤣🏆

[@dallassukerkin6878]

So good to hear the other side of the coin on this matter! All I have heard previously was positive with no hint that there was any downsides to thorium at all.

[@eb4452]

Excellent, well thought out presentation. Thanks!

[@kaspermortensen2677]

Fantastic interview Jesse, super entertaining and insightful

[@davidhemsted5372]

Can you do a similar video with Copenhagen Atomics including their response to your comments on proliferation?

[@barry7608]

Thanks Elina, I have subscribed, because of your unbiased and knowledgeable video. I worked for 35 years in the nuclear industry, NOT power generation but lots of work with isotopes. To me, it's not a case of 'teams' or 'winners', its about making the right choice and videos and input from people like yourself should give us the best option. Keep safe and keep up the good work.

[@FranzJStrauss]

unbiased 😂😂😂😂😂😂 russia sits on the most of the nuclear fuel market do you astroturfing trolls think we are all stupid???

[@pastorDbow]

Best presentation I have seen on this technology!

[@davemcbeardface8976]

Hi, this is the first time I’ve heard of this and the first video of yours I’ve seen. I found the information easy to understand as you explained it well. That said I think I need more information before I can comment on what I think about this interesting topic.

[@1kreature]

Great video, but one mistake is to assume we would long-term store the liquid fuel as spent. All waste elements would be extracted from the fuel on a continuous basis, in a process that would probably be economically viable from just selling other trace elements being produced. A lot of very expensive isotopes for science and medicine would be more available this way (molybdenum-99 etc). The unwanted biproducts would be in oxide or fluoride form that after aging becomes for example metallic forms like Neodymium. With the electric car industry requiring staggering amounts of this rare earth metal this waste also becomes a business. (Neodymium-147 has a half-life of 10.9 days so not very much more aging than is done with cheese.) When it comes to proliferation the liquid uranium reactors would not be any better as the actual risk is in a reactor where different parts of the biproducts can easily be separated out during operation. As-is, non-liquid reactors are run to produce materials, and then the fuel rods are liquified and centrifuged in a separation and enrichment effort to produce the same materials. The liquification can be based on salt again, so pretty much the same.

[@seanbutterfield1]

While a new regulatory and oversight scheme might be needed to secure the Protactinium as it decays to U-233 stored outside the core in some countries, I don't think that is any more a proliferation risk than the Plutonium in current waste streams, or indeed the U-235 already used in current fuels. Team Thorium!

[@SonnyKnutson]

Agree. The many many added safety benefits of LFTR's seems like a nobrainer to me. One of the biggest being that there is no high pressure water in the reactor that can spread into the atmosphere in case of a catastrophy. It simply leaks and goes solid without much contamination except some local.

[@CraftyF0X]

Well I guess reporcessing and pulling out the Pu-239 from spent fuel is chemically a lot more challanging than just fluorinating your Pa-233 decay tank until the U-233 hexafluoride bubbles out which is about one more step away from being ready to make a bomb out of it. Now Iam normally the one who dismiss proliferation risks, as I think it's bizarre to imagine a bad actor with the resources and scientific background to covertly steal the material, build a bomb out of it (without any testing) and use before anyone notice, when going a much cheaper and frankly technicllly simpler route with bilogical warfare just makes a tons more sense even if said actor just wants to see the world burn, I thought it worth mentioning why the two things are different by their difficulty. Seperating is actually easier, building a bomb out of it when you can only remote handle because of U-232 contamination with hard gamma decay chains is not trivial matter at all. So as many thing it is actually nuanced, its true that separation is easier but does it make it more of a proliferation risk ? I don't think so.

[@seancollins9745]

the sub critical design is good, and if the pump shutoff, the reactor just cools down, eventually, passive safety is a win.

[@johnwaldmann5222]

The regulatory regime in many countries is designed solely to defend old school 1950s reactor designs, and the later minor (improvements on that design). Or rather, the regulatory regime is designed to defend the regulatory regime. The risk of weapons proliferation due to use, disposal, and potential abuse of thorium reactors is far less than the risks associated with use, disposal and abuse of medical grade nuclear products. The risks of failure are astronomically lower than light water and presurised reactors. And the thorium reactor design lifespan is substantially longer vastly reducing decommisioning costs. To make a comparison, the paperwork required to obtain a thorium reactor licence in mosy countries (those signed up to the present international regulatory regime) exceeds the amount of paperwork required by the entire global civil aviation regulatory regime to authorise use of a new aircraft. Not because the regime is pointless, but because the nuclear regime -unlike civil aviation- is based not on sound scientific and engineering premises, but because the nuclear regime is designed purely to reflect cold war premises, and 1950s high pressure reactor designs and not open to adaptation to accomodate newer technological developments or scientific advancement. Fusion reactors actually have a easier future simply because it steps arround the entire nuclear regulatory regime.

[@CraftyF0X]

@@johnwaldmann5222 Couldn't have said any better.

[@grumpy3517]

Very valuable information. Thank you!

[@valkyriedd5849]

Beautiful presentation, very informative.

[@John83D]

Overal it is quite nice video describing the LFTR in general, but there are missing some very important things regarding the benefits of LFTR which make the LFTR shine. In example the section comparing thorium abundance. We don't have to mine it at all, it is byproduct of normal rare earth minerals mining. The infrastructure is there. Second thing missing is the fact that the fuel in molten salt is used almost entirely circa 98% in contrast to 4% with solid fuel. Hence there is much less waste produced for the same amount of energy produced. There is also missing the fact that some LFTR designs plan to use the constant processing and purification of the fuel and use the "waste" for other things, such as pu238 for deep space exploration, curing cancer etc. Also if they manage to create a reactor core and all the piping resistant to corrosive nature of the salt they can use the same material for the waste containment. One of the byproducts of the LFTR is also tritium which we need for future fusion reactors. Also another huge benefit is that we can take existing nuclear waste add it to the salt and make energy of it plus further reducing the waste to a point where we don't need to have long therm storage at all.

[@RobertBalejik]

btw there is already such material (Hasteloy-N) which was tested at the oak ridge

[@mirrorflame1988]

This is very interesting topic - Indian nuclear policy has been focused on Thorium since the beginning as we have the world's largest or second largest deposit. Furthermore, we were cutoff from all nuclear discussions for decades (Pakistan was allowed though despite being known nuclear proliferaters) so we had to develop our own way with things regarding Thorium reactors (Breeder reactors). We are focusing on becoming self-sufficient energy power with our own reserves in the next stage of our nuclear policy.

[@12pentaborane]

It is an impressive feat, it's also a testament to the CANDU reactor to be able to run on it as well.

[@miscbits6399]

Thorium doesn't lend itself well to solid fuel systems due to the extreme gamma issues of the fuel rods and produces at least as much waste as uranium if used this way. Indian efforts have been mostly geared towards solid-fuelled operation and suffering accordingly The best way to proceed is to get a working molten salt system and THEN switch to fuelling on thorium. Keep an eye on Wuwei...

[@Rory20uk]

Very enlightening - thank you!

[@vauchomarx6733]

Very informative video, and good to see you address the proliferation risk! That is also my main concern, and it's often missing from the discussion. One model that seems safer and more useful is to use a combination of Thorium and depleted Uranium as fuel…

[@RexxSchneider]

But neither thorium nor depleted uranium are fissile, so you need to transmute them into U-232 and plutonium in a breeder first. But because it's relatively simple to chemically separate those products from their precursors (when compared to uranium enrichment), it immediately creates a danger of proliferation of weapons-grade fissile material. I'm sorry, but that doesn't fit my definition of "safer". YMMV.

[@ldkbudda4176]

@@RexxSchneider Proliferation is a BAD argument !!! The countries with long history of operating nuclear reactors and even thouse countries which posess or produce its own nuclear weapons, how that "proliferation" mantra forbids them to design, build and succesifuly operate liquid salt thorium reactors on their own soil? You see - your many times expresed mantra is 100% debunked !!!

[@MrDamged]

Great video! Please do one on CANDU / heavy water realtors. They have a lot of hype around them like Thorium reactors. It would be nice to see an unbiased video on these too.

[@AlldaylongRock]

There have been tests for the use of thorium as a fertile fuel in HWRs that are using reprocessed LWR fuel. Speficically Pu-Th MOX , a Pu-Th-U MOX, or a sort of a «breeding blanket» similar to the ones utilized in fast breeders. India is the country most interested in developing this technology at the present. I personally like HWRs quite a bit. And its a much more proven technological basis than LFTR.

[@FokastudioGreece]

Wonderful analysis ... and I love the enthusiastic tone...

[@dondouglass6415]

Great and fascinating video... thank you and Huzzah!! 😊

[@cerealport2726]

It'd be great to see a video explaining how new reactors could use spent Uranium fuel.

[@albdamned577]

Molten salt as a heat exchange is a pretty cool idea, even without a nuclear heat source. I feel like I'm in the early days of the steam engine.

[@coachhannah2403]

Early days of steam engine while the rest of the world is far ahead.

[@tjairicciardi9747]

amazing video, really appreciate the plain language explanation

[@confuzzius]

Great video thanx Elina! First time I actually have a reasonable understanding of the issues at stake in Thorium tech.

[@ccibinel]

Great video. Really hoping that the CANDU SMR projects continue to be funded and eventually produce effective reactors. Widespread use of SMRs that also burn waste would be a huge benefit to reducing waste and fossil fuel use. Not sure if the SMR designs provide for any tritium extraction for fusion research but given the general design of SMRs I doubt it.

[@bulbarobat]

Why is everyone so worried about nuclear waste? After all, nuclear waste is literally a few square meters of space near the station. Unlike coal-fired power, which emits thousands and thousands of times more radioactive waste, among other things. When coal is burned, radioactive waste is also generated. Does anyone take this waste into account? No. In fact, when the pipeline to Germany was blown up, it was like dropping several atomic bombs. But no one cares at all.

[@ojiisanthewise7260]

Thank you for the video Elina!!! My belief is if Oakridge had this working in the late 60's and humanity can put a person on the moon around the same time, based on the safety benefits, there should be a way to engineer all of the shortcomings such that in comparison to uranium, thorium would win out. Uranium reactors are the horse and buggy. I'm sure if KZbin was around in the late 1800's a comparison video with the automobile would point out that automobiles are too complex, potentially dangerous for drivers due to high speeds and needs a new source of fuel that would cause waste. Therefore, we should continue with our tried and true horse and buggies going forward. New and better energy sources are the solution to many of the problems that plague humanity.

[@goiterlanternbase]

They don't had a working reactor, they had a build reactor, that was causing problems on end and was given up, because of that.

[@ojiisanthewise7260]

@@goiterlanternbase You are incorrect sir, please try again.

[@bombheadgames9565]

What a good explanation. Well done for being impartial and mentioning some of the negative aspects and challenges of Thorium as well as the good, many other posts claim it is almost non-polluting, whereas you give details on how toxic it is likely to be.

[@frankdecardenas53]

Thank you for you explanation is veer enlightening, I was always wondering why this technology was being used more.

[@SonnyKnutson]

About the storage for the salts. You say they are liquid but they are not liquid in atmospheric temperatures. They melt at around 2-300 degrees. So they would be solid for storage. Like table salt :P

[@chapter4travels]

Yep, she got that part wrong.

[@dalethomasdewitt]

Salt dissolves readily in crust waters.

[@chapter4travels]

@@dalethomasdewitt Not that form of salt.

[@zeon5323]

Elina, please talk about gas cooled reactors (HTGR) like the one that was at Fort Saint Vrain in Colorado USA. I love this content.

[@philipyoung7034]

Yes, I have been commenting for years on that reactor as an example of a thorium solid fuel reactor in commercial use. Fun fact: I discovered that reactor because an environmental group used it as an example of a "successfully" decommissioned reactor returned to nature. It was successfully decommissioned, but it was then converted to a conventional, natural gas, power plant.

[@zeon5323]

@@philipyoung7034 Creating even more pollution!

[@bulbarobat]

@@zeon5323 Why is everyone so worried about nuclear waste? After all, nuclear waste is literally a few square meters of space near the station. Unlike coal-fired power, which emits thousands and thousands of times more radioactive waste, among other things. When coal is burned, radioactive waste is also generated. Does anyone take this waste into account? No. In fact, when the pipeline to Germany was blown up, it was like dropping several atomic bombs. But no one cares at all.

[@philipyoung7034]

@@bulbarobat zeon wasn't commenting on nuclear waste, but the carbon emissions from the gas generator at the former nuclear facility. In other news: No one cares about Aberfan.

[@bulbarobat]

@@philipyoung7034 You're comparing the emissions from a match and a smoking truck. By the way, some more funny math: those who blew up gas pipelines literally dropped 15 atomic bombs on Europe. Because all the energy that was previously obtained from gas will need to be replaced with coal. Moreover, coal of low quality and low heat capacity. And when coal is burned, radionuclides are emitted. But no one cares at all. And the culprits are not looking for it at all, although everyone knows who did it.

[@dday1412]

Very helpful. Thank you!

[@erikjohansen1873]

Brilliant explanation of the process.

[@wollm1325]

Thank you for this balanced and honest analysis. Ther is a lot of talk going on and it is hard to determine what is true and what is wishful thinking. What i take away from your talk is that the process engineering is still incomplete and needs research and proliferation is a concern. I think these are challenges we can crack and the promise of safe and low cost energy is still there in LFTR. This should get more attention in the university community and politics should free up the way to develop this.

[@YourFriendlyNuclearPhysicist]

Indeed 👩🏽‍🔬☢️ thanks for your comment

[@axl1002]

How can you call it balanced and honest when she intentionally misled the audience to believe that fissile Uranium235 is only 3 times less common than Thorium by using the numbers for the useless U238?

[@wollm1325]

@@axl1002 it was shown in the graph.

[@axl1002]

@@wollm1325 It doesn't matters, the uninformed people will understand 3:1 because that is what the scientist said in general. The people don't care for the details.

[@enriquegarciacota3914]

Hello, thank you for this. Regarding storage of the molten salt waste materials, you mentioned that liquids are difficult to store long term. Wouldn’t they solidify once they are out of the reactor (they would be “salts”, not “molten” any more)?

[@yetanotherjohn]

I think the fluorine-salt compound itself is a liquid, even at room temperature. MAYBE? xD

[@jimswenson9991]

FLIBE salt is solid at room temp. and actually dissolves only slowly in water. Not too bad, imo. Fresh out of the reactor, with no chemical repurification cycling, you would have radioactive self-heating. Enough to keep it molten for a month, maybe? I dunno that. There are usually two stages of conventional spent fuel storage. Fresh&hot, in a pool. Older&warm, in a sealed casket.

[@chapter4travels]

You are correct, she got that wrong.

[@petersteenkamp]

You can also remove the Flibe salt through vacuum distillation. In other words, you can theoretically separate the salt, the fuel, and various fission waste products in a process that is similar to what is used in the oil industry to separate various hydrocarbons, just at much higher temperatures and more corrosive conditions. Technically challenging but in theory possible.

[@keithdowsett1352]

Unlike the oxide based fuel in uranium reactors, many heavy metal fluorides will react with atmospheric moisture. This results in production of toxic HF as well as water soluble complexes which can leach out. So, 'dry' storage underground would not work well.

[@laserguidedbrick]

Thank you very much for this explanation and pointing out some the various issues with available current technologies and waste management of Thorium reactors. I do agree that continued development of reactors that use existing stockpiles of spent fuel would be a better in the long run as we fully understand the technology that is uses. Also, the recycled spent fuel will require less storage time at the end of the process.

[@mariagavriilidou7525]

Amazing video. I really love they way you take a subject and you break it down into parts and then start to explain each part. It is so helpful to understand the topic. Thank you can't wait for your next video ❤️

[@gericla]

Okay, on your video commenting on the "Nuclear Waste" video, I said I wanted a video on Thorium--and here it is, and as complete and thorough in answering all my Thorium questions! Very impressive! And thank you for educating us on these important, possibly emerging technologies.

[@sixp1205]

Team Thorium! Well done. I would love to see major DARPA emphasis placed on research and development. Any process that transforms 200,000 year half-life waste into 200 year half-life waste is moving in the right direction.👍

[@SilvaDreams]

Ironically most of that "waste" isn't fuel rods but clothing and lab equipment or anything else that comes in contact during the refining and processing of uranium.

[@dactylntrochee]

I was afraid you were selling thorium and playing down its weaknesses, but you came through in the last half and brought up the realities that I knew must be. Very good, as always.

[@RGB06084]

Great stuff Doc!

[@samjohnson5044]

Thank you very very much for this comprehensive overview.

[@g.m.5448]

Thank you, that was a pretty good explanation and summary of the state of art. I always wondered about the Thorium hype, and was a little suspicious it might not be as rosy as sometimes depicted. Your presentation confirms my reservations. The aspect of proliferation of weapons grade fuel might indeed remain the biggest obstacle for wide commercial use, compared to the technical issues which probably will be solved sooner or later.

[@dogoku]

Hi Elina, can you discuss about high-temperature gas-cooled reactors like Japan's (red/pink) Hydrogen reactor that got activated last year and claims to produce energy and hydrogen in an environmentally sustainable way? Also any thoughts on the recent development about nuclear fusion announced by the Americans.

[@anxiety4daysmusingmedic891]

This please 🖤

[@MonsterSound]

The recent development about nuclear fusion announced by the Americans majorly downplayed the fact that to charge the lasers required 300Mj. They focused their announcement on the measure that the 2Mj lasers produced 3Mj of output, and WOW ignition was achieved. That is very, very far from net energy gain. 2c

[@nuanil]

@@MonsterSound Yeah Fusion announcements only ever count the energy difference in the last step, and leave out the 19 other steps along the way that cost them 99% of their energy.

[@upstream1942]

I really apreciate all the pros and cons, for a balanced evaluation of the thorium reactors' possibilities. Now do SMR, please 🙂

[@fabrizionastri9484]

Great video, and very good conclusion with your own view

[@Ryukachoo]

Unfortunate reality: It's easier to sell a molten salt reactor to the public because of the very high passive safety, and honestly public perception is BY FAR the largest barrier to nuclear research...so might as well embrace that

[@hewdelfewijfe]

The thing is, the AP-1000 pressurized water reactor has basically the same passive safety system. Arguably the biggest unique safety advantage of a liquid fuel salt reactor is that the cesium and strontium form very strong chemical bonds with the salt, so strong that if you blew up the reactor with a bunker buster missile, the cesium and strontium would probably remain in solution in the salt which would solidify on site.

[@thomastl9581]

Hi Elina, In the future I would like you to explain the type of reactor on Thorium and U238 which are BOTH found in abundance in combination with a small particle accelerator( already in existence) in order to produce fission between the two of them. Thank you for your lovely and cheerful explanation! All the best to you! Professionals like you will be in high demand in the near "interesting future that awaits us

[@Indrid__Cold]

Excellent presentation. You answered virtually all of my questions. I'm thinking, the thorium "deal breaker" is the high gamma ray emission of thorium waste. Shielding against gamma rays is extreamly difficult. Its like trying to eliminate light from a nightclub. Any tiny "leak" is like a gamma knife, and can go undetected for a time if it arrises newly. Its a huge challege for gamma ray source labs, and they are not dealing with the huge amounts of material the industry would need to ramp up to. Not impossible, but inconvenient and dangerous.

[@wezleyjackson9918]

Go tell the Chinese who claim to have a Gen4 commercial grade research Thorium LFTR reactor running safely. Just because the USA and entrenched Uranium/Plutonium industry turned their back on Thorium LFTRs and development has only gone ahead by India and China, doesn't mean we can conclude this technology cannot be safer than traditional Uranium/Plutonium nuclear.

[@matthijsklomp]

Great to hear someone who knows what one is talking about. Very well done!

[@alexandrosgiannikos9796]

Great overview with pro and cons

[@cbhirsch]

Great explanation of the complete fuel cycle. Thanks for making this video.