Reactors of the Future (Generation IV)

[@kurzninja]

The most impressive part of this video, to me, was the professor's ability to write backwards. Incredible!

[@jimtrowbridge3465]

He probably wrote normally; then they flipped the screen.

[@_PatrickO]

He writes normal, they flip the video. It is an excellent way to make videos with a whiteboard. He is actually right handed, not left. He wears clothes without writing on it, so you cannot tell the video is flipped.

[@andrejrockshox]

@@_PatrickO nothing is flipped. he's writing on a mirror.

[@NickBFlair]

His watch is on his right wrist and he's writing with his left. Flipped.

[@DJ-eu1js]

I’ve been watching these and that is my primary observation

[@dysonspreybar4903]

Did the marker have its own mic?

[@wochuchen1349]

The equation for efficiency to temperature dependence is inaccurate: Eff = 1 - Tcold /Thot would be different if you use F vs. C, let alone K. It is over simplified. There is precise one in thermal dynamics of college level.

[@puncheex2]

@@wochuchen1349 Sure but in any country but the US (my country, as it happens) the SI unit is used: Kelvin. This is understood. Even among US physicists.

[@justgivemethetruth]

hahahaha

[@ikester475]

@@puncheex2 Indeed. The temperature scale is relative to absolute zero. I was waiting for the presenter to mention that.

[@scottcoston7832]

Pitch... higher frequency... it was annoying

[@hynesie11]

His backwards writing skills are next level

[@darksnipedflyingmadness6830]

You can just mirror the who scene in post-processing.

[@dokenboken5542]

Exactly that. He's wearing a wedding ring and a watch on his right hand? If he was left handed, he'd still have his wedding ring on his left hand as that's the culture in the US and apparently he's from Illinois.

[@MaxRuso]

Doken, damn!

[@eitkoml]

It just requires a little practice. I learned how to write backwards, upside down and upside down plus backwards in school. I was just trying to keep myself awake when the teachers' lectures were so boring and they went so painfully slow.

[@daos3300]

@@darksnipedflyingmadness6830 hehe.. you know people are going to fall for it every time

[@peterkotara]

_"Did the marker have its own mic?"_ No, a foley artist dubs it in during post production. I believe they use a mouse.

[@OmarDelawar]

Lmao enough with the pen noise jokes/puns already

[@manw3bttcks]

I wonder if the audio software could be told "filter out that high frequency sound at 14000hz" or whatever the pen squeak is.

[@ibrahimdeniz7308]

I can tell you use reddit. Why do you hate yourself? Would you like a reward for that?

[@Kitsudote]

@@manw3bttcks Most likely, doesn't sound too complicated to implement, but the real question is: Do we really want that? The squeaky marker is now a staple of this channel. Honestly, if he ever did merch, that needs to be a t-shirt or something 😄

[@sonofsomerset1695]

Meh, I'm gonna wait for the Gen V before I get one.

[@3vimages471]

You can get Gen 3's really cheap on Amazon now.

[@treasurehunter3744]

Dusty Plasma Fission Fragment Reactor

[@spvillano]

@@3vimages471 they're cheaper on eBay, although quite a few appear of Chinese manufacture.

[@protorhinocerator142]

I would say a fusion reactor is Gen 5.

[@heinz-haraldfrentzen1261]

@@spvillano Be sure yours comes with the original box and warranty papers, lots of fakes out there :-)

[@stephanfuhrmann6519]

I believed pebble bed style reactors died after the big problems of the THTR-300 in Germany. Interesting to see that these concepts are being worked on again. Thanks for your outstanding videos, professor!

[@karendarbres]

What problems?

[@nuhrii3449]

@@karendarbres it got clogged, it was mostly cherynobl fears and bureaucracy

[@fatsassin2546]

@@nuhrii3449i just like to imagine some npp worker getting a giant steel plunger And going like "Aw hell, the reactor is clogged again"

[@Petriiik]

​@@karendarbreschernobyl panics lead to a "non compromise" polici, turn off everything and forever.

[@timmyjones1921]

Seems India has a auto machine re loader and takes out spent rods at the same time and is already operational and China is already running Sodium Nuclear Power Plants.

[@allniterz9248]

“Down to a couple of weeks” I work as a nuclear contractor in the us and I can confirm that. 4 week jobs are considered long within my craft

[@bobdexter1029]

Depends in what work is being done and if its a PWR or BWR. It took almost 2 weeks for me to dry the generator out on my last BWR nuke job. Alot of dirty stuff being lifted and the deck was be taped off daily.

[@brianburk2559]

That was one really good aspect of the RBMK. Being able to fuel it without shutting down

[@mbican]

I had the same thought. Let's bring RBMK back 🔙

[@piotrd.4850]

Add to this much lower power density ....

[@YZFMANIAC08]

@@mbican 🤣🤣🤣

[@davidcampbell1420]

CANDU does this too. And Canadians uh.... use concrete domes to protect their cores like sane poeple. /facepalm Oh USSR...

[@loglad5394]

​@@mbican Just not the 1000

[@mgatelabs]

I still remember walking into a fast breeder reactor in India, it was a school thing, also got to see their largest electron scanner device for finding defects in large metal structures.

[@kgd9725]

When did you visit this reactor in India because according to Wikipedia its still under construction?

[@mgatelabs]

@@kgd9725 sometime in 2008-2009

[@pradeepkachari4648]

@@kgd9725 He probably visited the fast breeder test reactor (reached criticality in 1985), which has been in operation for quite some time now. en.wikipedia.org/wiki/Fast_Breeder_Test_Reactor

[@hvanmegen]

Damn, this channel is a gem.. subbed!

[@hbone_alldayeveryday]

"As long as we have an economic imperative for the future, these could be the reactors of 30 or 40 years." Can someone get this man a larger microphone.

[@stupidburp]

Expecting to wait at least 30 or 40 years is a defeatist attitude. Some of these designs have already had functional research reactors built a long time ago. All that is required is the will to build a pilot commercial reactor and then copy it. That could be done in less than ten years if we make it a priority or it may never happen if we don't.

[@Bradgilliswhammyman]

Too expensive and they never are profitable.

[@stupidburp]

@@Bradgilliswhammyman Check out the profit video comparing nuclear to natural gas power plants on this channel.

[@zolikoff]

It could be done in a few years but still expect to wait 30 because the world doesn't want it. They're too scared, politically or otherwise, of anything "nukular".

[@pedrobrando4606]

The Navy has a near perfect safety record when it comes to Nuclear energy or at least you do not hear of accidents.They could permanently dock a older ship.I believe a nuclear aircraft carrier could power most of a city like New York. The conventional carrier I was on produced 100000 shaft horsepower.I worked in the boiler room on CV-62.

[@strcat666]

The Thorium Cycle was prototyped 60 years ago. A Thorium reactor was shown and mentioned in this video. It is the green zero carbon technology that get rid of Coal and Gas while we are refining the sun based power sources and the batteries we need for the future. so yes you are correct sir.

[@peachtrees27]

This was awesome. Thank you for putting this together. Hope you do more of these!

[@pmdurand6765]

I would be very interested in learning about small modular reactors, Could you please make a video about these ?

[@atheistpeace7579]

been using them on submarines for decades

[@sommeone]

In case you're still waiting, he made 2 videos on SMRs and one on MMRs :)

[@davidcampbell1420]

I appreciate the professor's online mini lectures. Thank you for doing them! I feel one major advantages of Gen4 wasn't touched on strongly enough. It seems to me most (but not all) new nuclear is smaller startups employing molten salts. Configurations or design ethics to eliminate nuclear waste by using it as fuel. That's a political problem solved. Pebble bed makes this goal harder by making the waste really hard to process. Simultaneously, using liquid fuel jumps the efficiency to near full efficiency, rather than nearly zero. Most of the transuranic actinide fission products burned away, most of what's left is valuable material able to be sold. What's left of waste won't matter in it's quantities or lifespan.

[@LordZontar]

Remaining waste radiologically hazardous for only 500 years (as opposed to 10,000 - 30,000) with thorium fuel cycle and fast neutron reactor designs. A marked improvement in both waste-stream safety and fuel efficiency.

[@paulbedichek2679]

Absolutely not! TRISO is never meant to reprocess in any way.

[@davidcampbell1420]

@@paulbedichek2679 I like TRISO for niche scenarios such as diesel generator replacement systems.. its just so simple. You might happen to know... are any of the TRISO systems load following? If so the annoying waste stream might be massively minimized due to the business use cases. Big stuff, its molten salts all the way. Hurry up and wait!

[@paulbedichek2679]

@@davidcampbell1420 Yes,TRISO load follows, there is no troublesome waste problem with TRISO it is a containment system unto itself when the majority of its energy has been extracted. You can load them with Th and spent fuel if the need arises.

[@davidcampbell1420]

@@paulbedichek2679 If TRISO based reactors can load follow then this is amazing. Does this mean that micro reactors rated for 8 or 20 years prior to refueling, assume 100% loads throughout those years? Could that not mean far higher expectations of fuel life if their average loads are a fraction of capacity?

[@blakevollbrecht9026]

I find it weird that activists were able to stultify the progress of nuclear energy development; It is the next level of progress; That's undeniable. It's good to criticize any dangerous/polluting nuclear, but we need to get better at nuclear and replace fossil fuels with it. Paving everything with solar panels is bad for the environment too, and it probably won't meet the energy needs of the future, because we're always going to want to do more and use more energy. There have been hundreds of nuclear reactors built since the beginning 60-70(?) years ago, and only a few of the earliest-built reactors ended in disaster. Fukushima was built from 1967-1971. Chernobyl was built 1972-1977. Three mile island was built 1968-1978. How many issues have there been with reactors built in the last 30 years? There are over 400 in operation; We're obviously learning how to make them better, and there are all kinds of new avenues to explore there that can lead to significant progress. We need better reactors to reduce our society's footprint on earth and we need them for any type of sci-fi future that you might want to build elsewhere. (e.g. solar is terrible on the moon; 1 night lasts 15 earth-days. Also, solar energy obviously gets worse and worse if you want to go places that aren't as near to the sun)

[@Minuz1]

@ebulating what's irrational about people being scared of 500 Bn $ of disasters and counting.

[@boggless2771]

@@Minuz1 citation needed. Also, how much has been saved because of how cheap nuclear is. Not to mention fossil fuels had to become more efficient to compete with nuclear.

[@Minuz1]

@@boggless2771 those are the rough estimates of costs for the 2x biggest nuclear disasters, chernobyl and fukushima. Those are moderate estimates, some estimates for fukushima will net you results of around 650 Bn $

[@boggless2771]

@@Minuz1 $15 Billion for cleanup. About half of nasas annual budget. The estimates for the whole disaster,including the TSUNAMI that caused it totals around $200B. www.forbes.com/sites/jamesconca/2016/03/10/after-five-years-what-is-the-cost-of-fukushima/#11f92d6022ed Your citations are still needed.

[@boggless2771]

Remember the energy industry is about 10% of Global GDP. The numbers we are dealing with are incredible. In 2011, expenditures on energy totaled over US$6 trillion, or about 10% of the world gross domestic product (GDP). - wiki.

[@kahuna414]

You are a very good explainer of difficult subjects. amazing stuff here.

[@rentacowisgoogle]

Whoever came up with that pebble bed design is a damn genius.

[@heinzhaupthaar5590]

Yeah, well, it's been quite a disaster.

[@YZFMANIAC08]

@@heinzhaupthaar5590 why?

[@davidcampbell1420]

@@heinzhaupthaar5590 I agree, why? I'm not a fan of pebble bed, but I haven't heard of problems?

[@caav56]

@@davidcampbell1420 THTR-300 high-temperature thorium reactor got fuel pebbles lodged in the feed pipe to the reactor core, in addition to the fuel elements breaking more often, than anticipated.

[@davidcampbell1420]

@@caav56 aha. So its because they are using a hopper. I had wondered if that would ever be an issue. Someone else in this thread mentioned it looked bad, too. Thanks!

[@imonlyamanandiwilldiesomed4406]

What about Thorium powered molten salt reactors?

[@jamesricker3997]

They have a small problem. The molten salt dissolves a lubricant on the pumps and the lubricant clogs the reactor channels

[@imonlyamanandiwilldiesomed4406]

@@jamesricker3997 Can you support this claim with evidence? I have video of an interview with the nuclear engineers/scientists who worked on the molten salt reactor and were asked if there were any problems with it and said that there really weren't (some issues with corrosion and tritium which were solvable): kzbin.info/www/bejne/laqyYYShYsR6o9U

[@tigertiger1699]

I'm Only A Man And I Will Die Some Day Didn’t they run it for ages...

[@imonlyamanandiwilldiesomed4406]

@@tigertiger1699 Ya, they ran it for over a year. I remember seeing a picture with one of the scientists holding a readout with 5000 consecutive operational hours circled on it.

[@tigertiger1699]

I'm Only A Man And I Will Die Some Day Absolutely.., I’m visiting a nuclear station tomorrow as it happens, taking my doubting Wife to get a calm professional overview 👍

[@superdoobo]

This guy is a genius at writing backwards!

[@seedcraftthree]

The advance from current nuclear fuels to the new pebblebed method reminds me of the advance from musket balls to bullet cartridges...this was very educational by the way, thank you

[@lorriecarrel9962]

I love listening to your videos,you do such a good job breaking it all down.

[@encinobalboa]

Dear Professor: Thank you for your very informative series of videos. Please do a video on breeder reactors and the potential they have to not generate waste products which is a big problem with current commercial reactors. Also, please take a look at French Nuclear Program and the social benefits that this program, i.e. cheap electricity and reduced carbon emissions.

[@JK-rv9tp]

The Canadian CANDU heavy water system, around since the 70s, has the ability to be hot refueled. It also runs on natural uranium so you don't need access to enrichment.

[@mikeknecht9665]

I wish I had you as a prof. back in the 80's

[@andrewlambert7246]

Refueling downtime a major weekness with light water reactors. It means that one has to have another reactor to compensate the loss of power.

[@aaroniter8163]

7:48 When I read the text below it and noticed it was my native tounge (german), as well as this prb. beeing an older version so the ideas of it has been around in my country for quite a while, I felt ashamed for what my goverment and country has done in the last couple of years. We had the technology to solve most of our issues, but politics and naive ideology of Wind&Sun made us blind.

[@MrCantStopTheRobot]

It's kein politics, alles corruption.

[@sachinkrSharmavirescoenergy]

Great summurization of PBR. Thanks Sir.

[@dylbert140485]

Who needs nuclear research. Clearly everyone in the comments section knows everything already.

[@3vimages471]

Now I know how everything works I don't need you.

[@haliax8149]

I see this type of comment quite a bit, and it's annoying. Mainly because you're actively discouraging somebody's investigation, and thus ability to debate, of this topic.

[@turningpoint4238]

I know the one important thing and thats it's dam expensive and will be for the foreseeable future.

[@turningpoint4238]

@@haliax8149 ?

[@shadowpoet4398]

Hey, u want some whine with that wahh-burger and french cries? -_- this is fun stuff, try to have a good time m'kay?

[@k0zkk519]

Great videos professor, keep up the amazing work

[@alexej01]

Next episode: Pens Of The Future Same efficiency as today's pens, but without emitting a sound that stabs your brain.

[@Fish-ub3wn]

[@uploadJ]

Never heard it; mind over matter. Numpties, YMMV.

[@sbravo3761]

Grown ass adults out there crying over things not even babies would. Shameful really.

[@texasdeeslinglead2401]

Lol

[@nomangreybeard535]

alexej davidov yeah, i couldn’t make it past him writing ‘passively safe’

[@matejorsag6515]

He spoke so much about the pebble bed design whereas only one sentence about the molten salt designs, which are the most promising ones.

[@davidcampbell1420]

I'd agree. It may be unfair of me to suggest this, as I don't know this gentleman.. but I get the impression that because most of the promising new technology is small start up companies, they fall outside of the traditional nuclear industry.

[@AntiNeoFascist]

Agreed. He seemed stuck in the solid fuel mentality. Like even when he mentioned the molten salt, he referred to the salt as the coolant, and then followed up with "These all still follow the same basic idea of solid fuel in rods of pellets" while overlooking the designs where the molten salt is both fuel and coolant.

[@davidcampbell1420]

@@AntiNeoFascist Is anyone actually doing molten salts without liquid fuel? I suppose it might be one way to speed up new tech due to the dinosaur regulators... helps with one key safety issue that's always bothered me, with the pressurized water. Still though, I'm unaware of this statement of his being true?

[@user-xl5kd6il6c]

He had a partnership to shill the pebble bed design. He said so in a previous video, so that might be the reason

[@chazzhou]

Pebble bed design will enter commercial operation this or next year with HTR-PM (200MWe) reactor, and a scaled-up 1000MWe version will be built within the next five years. So far, all the molten salt designs are in the experimental phase. I think that's why.

[@darrenmarchant1720]

2:15 so a Thorium power plant at the south pole of Mars would be more efficient?

[@matthewgrotke1442]

Any heat exchanger placed in a cool environment will be more efficient than one placed in a hot environment. To increase the efficiency, you can either increase the hot temp and/or decrease the cool temp. Putting it on mars would decrease the cool temp.

[@FixItStupid]

Lies Of Nuclear Cancer For You Too

[@haliax8149]

@@FixItStupid morons like you everywhere

[@davidcampbell1420]

@@FixItStupid Cancer Medication Is Made By Nuclear Reactors :)

[@Nill757]

Brilliantly simple explanation.

[@Waldemarvonanhalt]

The Soviets made a class of submarines that operated with reactors that used lead for coolant. They were really loud, but it allowed for a smaller maritime reactor.

[@hamansing787]

When you say "really loud," does that mean audibly loud where the crew had to put headphones or loud on a radar ? Please explain. Honest question.

[@caav56]

@@hamansing787 Sonar-loud.

[@chrismusix5669]

China just opened an HTGR reactor in Shidaowan, a 4th gen reactor.

[@JesterAzazel]

I learned a bit about pebble bed reactors after playing Reactorcraft.

[@avada0]

4:24 I never realized this. So you can avoid using heat engines and the carnot limit(?!), to produce power. You can feed it to a solid oxide fuel cell, that coincidentally only works on high temperatures, but can be (according to claims 80-90% efficient). The big question is how efficient such a cycle can be? The output of it is water again, which can be fed back to the reactor for re-splitting. If it's insulated the heat loss should be minimal.

[@jamesleonardpanes9915]

"It's the Sony Nuke-Man. A personal portable nuclear power source. They were a big fad on Malnak. Come to think of it, they were the last fad on Malnak. " Alf

[@tburrows357]

Can’t the CANDU reactors refuel while running?

[@proximo1033]

The molten salt reactor uses fuel that is resolved in the carrier salt, reaches criticality only when introduced to the graphite moderator in reactor core, can be simply drained and separated from the moderator by means of gravity when all possible system fail, there's no need for any downtime while refuelling nor removing fission products, any fuel processing can be done during normal reactor operation. The salt doesn't have to be held under pressure while being at very high temperature, eliminating the risk of leaks, radioactive steam explosion, the necessity for hight vessels strength that can significantly reduce costs.

[@Dave5843-d9m]

The issues with all new designs are regulatory. Solid salt "freeze plugs" and dump tanks are active safety devices so they will exercise the regulators. Pumped fuel is another where they'll have difficult questions. What happens when the pump which moves highly active fuel goes wrong? How do you change it out without putting operators at any risk? It's a tough one to answer and it won't be low cost to solve. Simply not pumping the salt solves it entirely as there are no pumps to be regulated. Thermal convection will do the job. But that would mean a high fuel inventory so why not put the fuel in fuel tubes which can be lifted in and out just as we do right now with AGRs. The coolant can be the same salt but with no fuel content. That does need control rods but the industry expects to see these so regulations are easier.

[@ano2425]

At the moment the things you are talking about are dreams.

[@proximo1033]

@@ano2425 Oh really? check out this then: kzbin.info/www/bejne/p5XCnXWGl8qJqLM

[@proximo1033]

@@Dave5843-d9m the pumps in this design are not that critical because even when they fail the fuel will simply drain down completely without any dramatic situation so where do you see such big regulatory concern. Well-designed pumps can run for many decades well over the life span of graphite moderator. But really there's no need for this discussion because there are already many existing designs and experts that have MUCH more knowledge. Example? check out my other answer. So if you're interested then check out also Gordon Mcdowell channel.

[@guytech7310]

@@proximo1033 Issue is that salt forms cakes in the cooling system that break off and hit the pump blades, leading to damage or short life. Also with a failed pump, clogged with highly radioactive solidified salt is a nightmare. The MSR reactor from the 1960s wasn't fully decommissed until 2005 due to the hazard of getting the contaminated salt. A MSR reactor would have to operate using pellets or some other system to isolate the fuel from the molten salt to avoid the salt from being contaminated. However all future nuclear plants are on hold due to Fukashima & the huge cost overruns at Vogtle, GA plant. No utility wants to dump tens of billions into plants which are now largely unprofitable. Currently about 2 plants per year are getting shutdown and the only reason its not higher is because a lot of states are subsidizing operating costs to keep them running.

[@bobsmoot8454]

We need innovative Gen 4 plants NOW, and personally I would love it if they were either mini or micro reactors and spread them to every town city and village in the USA

[@chris03101996]

what about the molten salt reactor ??? there is models where the fuel is directely disolve in the coolant

[@adlucem9845]

No country is building thorium. Theyre prototyping fussion plasma. Thorium is a youtube fad.

[@mukiex4413]

@@adlucem9845 MSRs don't need to be thorium-based. They're designing several uranium-based molten salt reactors and making their way through vendor review. Fusion is a research fad. When they get a whole second of steady state, maybe we'll talk. Probably not tho

[@smacleod69]

Dude, you really know how to write really well backwards for the rest of us to read!

[@andrewheffel928]

You can't get a new nuclear power plant permitted in the US. Which is a shame, because until nuclear fusion is perfected, nuclear fission is the only reliable non-greenhouse gas producing power source we have. Hydroelectric is maxed out, there are only so many rivers. Wind only works when it is blowing, and solar only works during the day. Germany went with wind and solar, with coal fired plants as backup power. They now burn so much coal at night and when tne wind does not blow that Germany produces more pollution than before they switched to green energy. France stuck with nuclear power, and is doing just fine. We need to build a massive number of generation 4 nuclear power plants around the world to supply the worlds power needs without carbon emissions. By the time these nuclear plants are worn out in 40 years, hopefully we will have solved the problems with nuclear fusion and can switch to that.

[@spvillano]

@odegaard the Foundation series was a series of Azimov books on that subject. The Foundations kept knowledge alive for when civilization gradually rebuilt from the inevitable collapse.

[@akinoz]

Such a informative video, thanks professor.

[@velwheel3135]

Should we look into building low efficiency reactors where we can allow ' spent ' nuclear fuel to continue to decompose. The goal is to reduce radioactive spent fuel storage and environment contamination.

[@arthurzettel6618]

Finally, someone who thinks the same way I do on nuclear waste. Rapid Radioactive Entropy is what you are referring to. For the life of me; I believe that (R.R.E.) can be done but these Nuclear Engineers aren't thinking far enough out of the box. I mean Nuclear Waste could be rendered innert by Rapid Radioactive Entropy.

[@jeebusk]

Or MSR

[@haliax8149]

@@arthurzettel6618 Except that the OP's comment is false. High efficiency means less waste overall, and waste reprocessing can handle any leftovers.

[@AximandTheCursed]

The most efficient way to eliminate spent nuclear fuel/high level waste (trans-uranics and other actinides) that I know of is in a fast-spectrum reactor. Both Moltex and Elysium have proposed designs using Chloride salts in a fast spectrum analogue for this purpose. It seems like a win-win scenario to me, as you eliminate the waste while generating electricity. The design even allows for the elimination of weapons-grade fuel, once diluted in the salts.

[@strcat666]

That is The Thorium Cycle. The end products have a half life of less thes a week. The products are safe for reuse in a year.

[@allad399]

What is the feasibility of using thermal batteries to try and diminish refueling downtime and improving availability?

[@paulbedichek2679]

Natrium

[@paulbedichek2679]

345MW with 500MW for 5 hours from thermal salt storage.

[@williamolenchenko5772]

Moltexenergy.com has an interesting twist on the molten salt reactor concept. The static salt reactor keeps the fission products separate from the coolant.

[@KoralMae]

Great link. Thank you for posting it.

[@adlucem9845]

No one is developing MSR's. Theyre developing fussion plasma reactors that have 0 waste.

[@davidcampbell1420]

@@adlucem9845 About a dozen or more companies around the world are designing MSRs. They merely sit outside the traditional industry, so you have to seek them out. None of the media, or policy analysts seem to be even aware. It's all over KZbin though.

[@christopherhennings6615]

In the very beginning it is stated about Generation III reactors "that they have the wonderful feature of being passively safe... you don´t need to keep the water on it". Why did Fukushima then happen? From a previous video I had the impression that missing water was the problem, because even a shut-down reactor still produces heat for some time. Or did I got the reactor classification wrong?

[@heinz-haraldfrentzen1261]

From my understanding, the meltdowns that occurred in reactors 1-4 were the result of residual heat, and that the backup systems were placed below the reactor core. When the earthquake hit, seismic monitors automatically inserted the control rods, stopping the chain reaction, and then the backup motors and procedures for a shutdown began. One hour later, when the tsunami swept in, over the undersized seawall, the lower areas of the reactors flooded, where the backup equipment was. These systems shut down, and over the course of the next 48 hours, the residual heat from the reactors was enough to melt the core and the other materials around it, creating the "lava" that is associated with a meltdown. But that lava did settle within the containment structure, and remains there today. There were still however, gasses that were building up, and because the gas filters were located in the flooded area, eventually the release of hydrogen gas occurred, and caused explosions. While there were explosions, they were limited to areas where blast walls were built to prevent total building failure. The containment structures are still in tact. They will need to be maintained for 60 years, at which point, the contaminated nuclear fuel can be safely removed. I know...a bit long winded..but it is nuclear physics..

[@christopherhennings6615]

@@heinz-haraldfrentzen1261 Hey! Thanks for the reply. So the passively safe feature mentioned in the video here for generation III reactors is not perfectly correct, as even a shutdown reactor requires maintenance even though at a very basal level...

[@heinz-haraldfrentzen1261]

@@christopherhennings6615 Passively safe, from a theoretical prospective, is true when discussing how to prevent the chain reaction from continuing. But the real world example at Fukushima shows that not everything goes according to plan. I'm going to have to watch this video a few more times to better understand the concepts of the higher temperature reactors that could be developed. Sounds interesting, and I like to have this kind of information when I argue that nuclear energy is what will help us mitigate carbon emissions, while providing sufficient power, far better than wind and solar could do.

[@christopherhennings6615]

@@heinz-haraldfrentzen1261 Yup, the theoretical perspective is a tricky one. Thanks again for helping me out. I agree that regarding carbon emissions nuclear power is an option that should not be missed. However, from an insurance perspective I find it difficult that companies, e.g. Tepco, are allowed run reactors, but cannot cover the cost of the worst scenario or cost of radioactive waste disposal. At second sight this is even challenging for a nation, especially with the long decay time of some isotopes in mind.

[@heinz-haraldfrentzen1261]

@@christopherhennings6615 my guess is that power operators self insure, and since they are typically a regulated monopoly, there are protections from them bearing the full brunt of a full on lawsuit and such.

[@BokoMoko65]

This is amazing ! Thanks professor !

[@stevesilverman3505]

I would also be interested to know what defined generations 1, 2 and 3.

[@PavelSkollSuk]

Cooling: Lead would be too heavy for anything in industrial scale (also bismuth). Sodium is OK, but a little bit more dangerous for operation personel. Salt containing any halogens is really corrosive in high temperatures, but we can mostly deal with that some way. The "cold water" in the primary cooling circuit in nuclear power plant Temelín is about 290°C (hot is only above 320°C). Fuel: Thorium as a fuel is already used for example in India and Soviets have used it in Kazakhstan. But you don't have waste useful for nukes, so it is not so much supported.

[@uploadJ]

No mention of Gallium either.

[@paulbedichek2679]

Lead isn't too heavy.

[@NewJak14]

Really love your channel and teaching style! Looking forward to new videos :)

[@elefnishikot]

what about Liquid Fluoride Thorium Reactor?

[@haliax8149]

That's Gen IV.

[@adlucem9845]

No one is building thorium reactors for a reason. Everyone is actually developing fussion plasma. Zero waste.

[@elefnishikot]

@@adlucem9845 the us is not building thorium reactors because they are being suppressed by vested interests they are being researched by many other countries like india

[@davidcampbell1420]

@@adlucem9845 Tons of people are developing Thorium reactors. They are just outside the traditional industry. They are all smaller startups, who will leapfrog the older industry. In fact, the Thorium people have been helping the Fusion people. They've helped by employing some of the chemistry they've cooked up while working with molten salt design.

[@davidcampbell1420]

@@elefnishikot I see this too. The regulators and the laws surrounding this are absurd. You have Americans going to Indonesia to partner with that government to replace coal plants over there with molten salt tanks. Still, there's some hope, especially as "old nuclear" is essentially in free fall collapse.

[@yuanyuanzeng6442]

Interesting use of real time slide graphics semi transparent and alpha keyed during the recording of the presentation. Plus reverse image allowing writing on glass to appear right ways. Oh and the information is interesting too..

[@Elios0000]

worth doing a video on just MSRE

[@OleTange]

See kzbin.info/www/bejne/q3yWZ2qKbM1pkLs

[@thelimitingfactor]

Great work man!

[@BrianD146]

Listening to the Daily talk about carbon offsets with Delta airlines got me thinking about generation 4 nuclear reactors. There's about six different designs with six different criteria one of course is they're walk away safe / self moderating. They're non-proliferation, they burn more spent-fuel than they make and it shines for substantially less time. The benefits are so pronounced but even Bill Gates is got his own company building this right now. China, Russia, India and Indonesia are moving ahead while the Trump administration has given the green light to explore this new technology. I would like to see them as common as a hospital in any City. We're not talking about gigantic generation three reactors that can run away or meltdown. One of the generation for designs makes a lot of oxygen and hydrogen and this hydrogen could be used in airplanes. Now everybody wants to freak out about hydrogen flying around but right now they're full of kerosene so no matter what being in an airplane is not all that exciting if you're going to crash. At any time there's about 10,000 airplanes in the air and they could all be carbon neutral with a sustainable source from generation 4 reactors. There's also talk about airplanes running on methane that could be extracted out of the atmosphere and then put back into airplanes. The energy to extract as methane could be from generation 4 reactors. Same with desalination plants in many parts of the earth. If there's drought in one particular area you could have a generation 4 reactor on a floating barge that comes to a certain port and makes fresh water. The media has got to stop scaring people along with politicians. I would much rather live next door to a generation 4 reactor or any reactor than a fossil fuel plant. Start doing a real comparison of the deaths that actually come from radiation exposure versus industrial deaths from oil or coal, natural gas, fracking, even working on wind power or solar. Anybody who works at any kind of industry producing things runs risk of injury or death and nuclear to date is far safer then fossil fuels. I can start going on about the exaggerated fear of Fukushima or Chernobyl but there isn't room for that discussion today.

[@OsirusHandle]

Oh wow, you have a whole course! I saw the economics one, will now watch all the others :)

[@madrzegada3700]

damn squiking marker

[@uploadJ]

I never even heard it ... until the numpties in the COMMENTS section mention it.

[@uploadJ]

Numpty, if it had been finger nails on a chalkboard or someone chewing, that's a different story. I hope those two bother you as well.

[@MostlyPennyCat]

I know it's a non-issue, but the idea of super heated high pressure pipes fill of liquid sodium is terrifying. 😂

[@propelegant]

While I found the lecture interesting, I would like to have reference made to the historical context of reactor design. The original light water reactor was designed by Alvin Weinberg to be used in nuclear submarines and never intended for domestic electricity generation. In fact, he advised against there use as the design does not scale up well, being difficult to maintain safety. Alvin was then approached by the airforce to design a nuclear reactor for the airforce to match the submarines. Clearly, the light water design would be too heavy so he developed the molten salt reactor (which you refer to as GEN 4) which was built and tested in the 70s proving to be inherently safe and efficient burning up the majority of the fuel. (as opposed to the light water reactor which can only burn about 3% of the uranium). The strengths of the LFTR design were many including the fact that fuel is dissolved in the molten salt rather than relying on very expensive pellets or pebbles, there is no need for a hugely expensive containment housing (as required by a light water reactor). This type of reactor can be made small enough to fit on a lorry and cost about the same as a passenger aircraft to build.

[@maltekoch1632]

All systems have there problems. At light water reactors I would guess we know them the best. For example liquid fuel has problems when some elements falling out of the solution an pile up in pipework or other places. With the fuelballs we have worked in Germany and had problems that piles of balls don't behave nicely and get very chaotic. By this balls had very different times in the reactor. Like 5-10 times faster in the middle. The coating of the balls wasn't sufficient to hold back radioactive isotopes from the inside and leaked them in the cooling gas, which isn't wanted in the design. A broken pipe in the heat exchanger could have caused a runaway reactor like in Tschernobyl, because of the influx of water in the hot core.

[@davidcampbell1420]

I hope Kirk Sorenson, or any of the other start up companies trying to make this happen will have success. They seem so optimistic, and fresh, and come from outside the traditional nuclear industry.

[@paulbedichek2679]

Alvin Weinberg is a hero, but he also developed the LWR and the BWR,which are the safe clean cheap electricity we enjoy today the world over. Te first thing the Russian did was empty salt reactors for missiles these are the all day missiles Putin brags about, we know exactly where they have flown as they leave radioactivity. We will deploy the molten salt reactor with an IMSR which has many advantages over a LFTR,Terrestrial Energy although the Canadians were supposed to support it yet the went with a boiling water small reactor design instead, but US has smr PWR NuScale ,salt cooled TRISO test reactor Kairos, XEnergy He cooled TRISO,and fast reactor with thermal salt storage Natrium,plus a small experiment of a fast reactor with molten chlorides it would be nice to hear someone order a Terrestrial Energy IMSR,gthey are better than LFTR's in many aspects they run 7 years and are replaced, no pipeline or leaks everything contained in a pot can burn waste and Th. The best salt reactor would be ThorCom,they won't even talk to the US with our rediculous regulations a clean sheet with Indonsia,they'll write the laws and regulations together and they have a very small island for themselves to build the first one on with a cable underwater for a mile or two to the mainland.

[@pierQRzt180]

awesome video. The sources I found only list Gen 4 ideas, but they don't explain what they are trying to achieve!

[@derekanhalt3417]

I need to know what generation his DaVinci script is on.

[@kuroihana3228]

Really genius design Thank you very much

[@michaelmontana251]

Dude is from mirror universe

[@jeffhurckes190]

So, would the NERVA be an open-cycle VHTR?

[@EinachserLS]

A 15 megawatt helium-cooled pebble bed reactor ran in Germany from 1969 until 1988. During this time it apparently encountered all kinds of problems, had several potentially dangerous accidents, and released a bunch more radioactive materials into the environment than it was supposed to. One of the scientists working on the project for over 30 years therefore expressed doubts on the general viability of pebble bed reactors, and criticised their export into countries like China or South Africa. en.wikipedia.org/wiki/AVR_reactor

[@recklessroges]

More research is a good idea. I'm still stuck with the feeling that packing spent spheres can't be the most efficient. Tetrahedron pebble bed?

[@phobos134]

but also were llik 50 years into the future and may today better work out its kinks

[@paulbedichek2679]

Germans love coal and are generally pretty backwards technically,China and the US are both running HTGR's.

[@Goo-ke1rx]

@@paulbedichek2679 That‘s the result of the ignorance of the politicans and their blindness for new ideas in engineering and breakthroughs in research, especially in the nuclear-energy research.

[@paulbedichek2679]

@@Goo-ke1rx Yes, the Germans lost their nerve with the HTGR, the near accident I heard about was they were emptying the reactor of the spheres and one got caught in the door, no harm, but that was the last of German clean energy research for constant sources. Everyone who works on these US, especially XEnergy, and China, are very cognizant of the German design flaw, so progress is made. The Germans used to have confidence in their science and technology, but they are so frightened of the Russians that they do everything to make Russia stronger and more of a menace, they import Russian coal, oil, and gas, not only paying Putin so he can build more tanks to terrorize Urkraine and the rest of Europe, but Germany is in the forefront of helping the Russians to melt the Artic, Russia is cold, covered in permafrost and Germany needs a melted Artic so the Russians can dig more coal gas and oil currently under the ice and also get their fossil fueled ships to move through Russian waters so Germany can buy more goods from China the world’s largest burner of coal.

[@b.f.randall5580]

@Illinois EnergyProf, I'm curious what you think of the TWR that would use Depleted Uranium or just plain yellowcake.... That's the Natrium scale-up plan.

[@jebise1126]

yes some russian reactors used lead+cadmium for cooling... but making that liquid again when reactor was down was no fun thing

[@listerdave1240]

The only way ahead that seems to make sense is molten salt thorium reactors with a brayton cycle turbine and a steam heat recovery turbine. It addresses safety, fuel utilisation (and hence reduction of waste products). The carbon emissions from obtaining thorium are also much lower than they are for the equivalent amount of uranium required to produce a given amount of electricity. The major difficulty seems to be the continuous reprocessing cycle which involves a large number of different chemical and physical separation processes. However there is no reason why it should not work on a large scale if sufficient R&D is dedicated to the problem.

[@paulbedichek2679]

No,that is not the way at all, although I love the Brayton cycle, there are too many risks with it, steam is well understood,Th isn't needed, we can use it if we want but waste and fuel costs are not important. It is the cost of the reactor and time to build, the French already recycle all of their waste yet you find plenty of protestors who insist on coal power,as its organic and natural. Fast reactors mitigate waste streams more completely than using Th,the Russians have already closed the fuel cycle,US is deploying the Natrium system 345MW with 155MW of five hour salt storage.An ideal system would be the traveling wave reactor the fuel lasts hundreds of years and practically dirt is the result, the US and China are both researching these, In between would be a molten chloride fast reactor which the US is building a small experiment size to study.The LFTR built by the Chinese we all applaud, but it is 2MW,so years from commercial use.

[@stanleytolle416]

Molten Salt Reactors are allot better. They are absolutely safe, work at high temperatures suitable for high efficiency and industrial applications, can be refueled while operating, can load follow, their energy can stored to be used for peak power needs, they can power the whole country for over a 100 years on the present nuclear waste stock piles, so why so little discussion about them?

[@ano2425]

You are another victim of the thorium propaganda 😂 check the facs.

[@davidcampbell1420]

Right? All these companies need is a couple billion dollars in seed money to get the problems solved. Stuff like salt corrosion of piping seems like a pretty easy engineering problem to solve. Everyone's locked in by regulatory hurdles it seems. I feel someone's going to get it done sooner or later, and then suddenly out of nowhere there will be a renaissance of companies across the world doing it.

[@davidcampbell1420]

@@ano2425 Propaganda? The Thorium people are coming from outside the industry, not within it. They are starving artists. They can't even afford propaganda :) They'd be the victims of propaganda. Besides, thorium use in MSRs has been thoroughly tested for many years.

[@croftegan7993]

They are a no brainer.

[@croftegan7993]

Hopefully Thorcon will demonstrate the technology. kzbin.info/www/bejne/pXOUeqWweal8b8k

[@dporangecounty]

Are their any non-thermal fission reactor designs? Helicon Energy has plasma containment generator but it part of their fission reactor which may or may not become a commercial energy generator. Thank you.

[@cerebralm]

No one: this guys marker: LET ME SING YOU THE SONG OF MY PEOPLE XD

[@brmelez]

Why no mention of liquid fluoride thorium reactors?

[@maninthemiddleground2316]

I don’t know if anyone has noticed this 🤷‍♂️ .... Is there a camera trick? Or is this guy able to right backwards legibly??? 😱

[@alexmagno2]

Probably the video was inverted. Note that, from our point of view, he is wearing a watch on the right hand and writing with the left hand. It is possible to be a coincidence, but very unlikely.

[@33VMUH]

@@alexmagno2 Also, the breast pocket of his shirt is on his right side, not his left side. Finally, he is wearing his wedding ring on his right hand, not his left hand.

[@lowspeedyoyo]

@@33VMUH yup, but then he would be writing from the right to the left

[@dunneincrewgear]

I think he's writing on a mirror. The camera is behind him but filming his image in the mirror.

[@lowspeedyoyo]

@@dunneincrewgear yup!

[@daps87]

What about the CANDU reactor? Do you not feel that it qualifies as a Generation IV reactor?

[@TheSanych]

He forgot to mention, than liquid sodium fast neutron reactor is commercially operated right now. en.wikipedia.org/wiki/BN-800_reactor

[@AlexGullen]

Someone please tell me this guy is an educator too in the broader sense than just this offering. Wow, just wow.

[@kaya051285]

In Europe (and many other places) heating homes and businesses uses more energy than electricity. Nuclear could play a part in heating. Nuclear heat can be generated at low temperatures low pressure and would be close to 100% efficient The problem is you would have to build a big district heating grid. This would be slow and costly but once built it would last a hundred years and could be powered by cheap heat only nuclear reactors There would also technically be no waste because the waste can just keep on powering the nuclear heated grid indefinitely so long as humans need warm homes the waste is not waste but low power long lasting energy for the district heating grids. New reactors for electricity generation are 3-5 GW thermal. District heating reactors that are 1/10th the power so around 0.5MW and supply the needs of 200,000 homes would work the energy side would be very cheap. Nuclear should concentrate to address this market. It's a huge market. And the technology needed isn't an advance in nuclear but and advance in methods to build cheap distributed heating grids.

[@Dave5843-d9m]

Molten salts especially those with no moving parts can do all of this. The high core temperature makes efficient electricity but there is still much waste heat perfect for district heating or water desalination, etc.

[@davidcampbell1420]

I agree with you, and with David Elliott. In fact, the Chinese are planning a district heating system just like this. They're building it right now. I don't think it's anything as cool as the molten salt stuff, but it's a high thermal loop they're planning, for exactly this purpose. The nuke plant's heat exchanger loop will basically be the city itself.

[@paulbedichek2679]

@@davidcampbell1420 There are two different programs, one uses rejected heat to heat water in a district heating loop, the other would be ti build a new type reactor, very low cost, very safe and sited close to where people live, part of the question asked was the people's reaction, even though it is a brutal dictatorship,the leaders want to keep it that way and public acceptance is important.Chernobyl helped destroy the Soviet model. There are already district heatingnloops in different part of Europe and the world.

[@davidcampbell1420]

@@paulbedichek2679 I see. Ive often wondered about micro reactors that are coming. Helium cooled TRISO fueled ones are super simple. Or, if we can get molten salt reactors such as Elysium where it runs right at the edge of criticality and merely sips fuel. Anyway tiny systems that can replace boilers in large buildings. It would fill the role of natural gas nicely if regulatory regimes were in place. I dont see it as any different as how they inspect gas pumps at gas stations. Just require the HVAC company to allow inspections of the core.

[@paulbedichek2679]

@@davidcampbell1420 The Ultra Safe Nuclear co is building TRISO fueled He cooled 15MW reactors, OKLO wanted to get a license for their reactor1.5MW, fast reactor, sealed with heat pipes and super critical CO2 Brayton cycle turbine, but the NRC denied the license without prejudice so they can apply again. There are other companies building micro reactors that will go on military bases, they were printing the reactor internals which saves time and money.

[@mitchcard2708]

What about Candu reactors? Online refueling, can run well over 550 days without a outage.

[@markir9]

Yeah, seems none of the US experts want to talk about them. Seems like an excellent design.

[@zolikoff]

CANDU is not an acceptable design in the US because it has a positive void coefficient and the NRC will not have that. I did not make the rule, but this is it...

[@markir9]

Thank you for the insightful comment! However they could still discuss them? Also I note that their design has multiple redundant, non power necessary safety features (for the reason you mention I guess), and given their excellent safety record - still seems like a good design!

[@jaakkooksa5374]

Chernobyl-type RBMK reactors make refueling a breeze because you don't even have to stop them to replace fuel assemblies :-)

[@jaakkooksa5374]

@@TR2000LT Seriously, the fuel assemblies are in individual tubes which are accessible from above. Just open the cap, pull out the assembly and put in a new one. The reactor can operate at full power the whole time. This also makes it ideal for producing plutonium for nuclear weapons, because that requires changing the assemblies at a fast cycle because otherwise the isotope ratio will be wrong.

[@jaakkooksa5374]

@Matt S In Chernobyl a core catcher would hardly have helped, because the whole damn reactor exploded :-)

[@puncheex2]

Sure, at the risk of eliminating the outer enclosure.

[@Dave5843-d9m]

RBMK uses solid fuel so the burn-up rate is low and the fuel itself is expensive. Molten salts (or using fuel salt in fuel rods) solve the burn-up issue and they also solve the noble gas pressure issue. But fuel salt in rods will not retrofit into an existing water reactor designs because the temperatures are too low.

[@jaakkooksa5374]

@@puncheex2 Who wants to pay for an outer enclosure anyway? :-)

[@EDARDO112]

One doubt that I have is about the maintenance, I saw a news about a reactor that was shot down to refueling and they stated that while the reactor was down they take the time to do some maintenance that can only be done while the reactor is off, in that case how this kind of maintenance would be done? And isn't the RBMK reactors able to refuel while online??

[@jorgeneo560]

ahhhhhh stop that noise please!!!!!!!!!!!

[@kennyfordham6208]

😭

[@rabidlenny7221]

Could you find a squeakier marker?

[@thisisntsergio1352]

Bruh. What about THORIUM?????

[@OleTange]

See here kzbin.info/www/bejne/q3yWZ2qKbM1pkLs

[@nyinkercom]

Hi. So which one of these are used in the new Russian "game-changing" Brześć-300 plant?

[@rbfabc]

I scrolled to the comments only to confirm my presumption that the first one would be about the screeching marker

[@redcrafterlppa303]

You are practically describing the rbmk reactor in green. - on the fly refueling - carbon moderated - cannot blow up ; )

[@Blackshark876]

I would love to show this video to all the green people that want to turn off all nuclear reactors. I hope politics agrees with science and europe builds them.

[@danadurnfordkevinblanchdebunk]

It's going to have to happen in a climate-change future.

[@MrCantStopTheRobot]

The Greens are a strange cult. It's such a shame, but almost as a rule I can't think of any major party that actually matches their label.

[@samsawesomeminecraft]

how about a critical ball of high pressure uranium gas? I imagine the temperatures there would be extremely high, which offers great efficiencies!

[@caav56]

Look into gas-core nuclear thermal rockets. The problem is in keeping this ball from expanding too much and from leaking isotopes.

[@samsawesomeminecraft]

@@caav56 thanks! reading the wikipedia article was very interesting.

[@adamthethird4753]

Could have started and stopped at MSR reactors...solid fuels in all of their forms is a poor way to do it.

[@uploadJ]

No mention of the Hydrino reaction AKA SunCell (tm) by the Mills group.

[@hosmerhomeboy]

a fellow gordon mcdowwell fan i see.

[@uploadJ]

Mcdowell maybe?

[@hosmerhomeboy]

@@uploadJ ya that

[@jeebusk]

Uranium and Plutonium is great for bombs, Thorium is great for energy.

[@justgivemethetruth]

What keeps the lead, or sodium or salt from cooling down and solidifying inside the pipes carrying it? Is there any way to recover from that? But I think there is virtue in these molten substance reactors because a system under enormous pressure is a problem. The ability to walk away and have the whole system shut down on its own if a great benefit and a good selling point to the neighbors.

[@justgivemethetruth]

@Andy Geee - OK, but that is a lot of heat to generate ... what happens if like in Fukushima if the generators are not working?

[@justgivemethetruth]

@Andy Geee - not really responsive to my question.

[@greggolding2291]

CANDU reactors fuel online and they've been in operation for decades.

[@davidcampbell1420]

Heavy water CANDU with online refueling was the best of the old designs. It's lack of a need for an enrichment facility is also great in that it uses standard U238 with the 0.7 U235 naturally found in ore. What's nice about this now is because the fuel pellets are simple chemically/neutronically. Moltex, which is a UK company collaborating with New Brunswick Power are going to take the CANDU waste and use it as a fuel in a molten salt design. Liquify it and burn it right down to nearly nothing, while powering your cities.

[@greggolding2291]

@@davidcampbell1420 All great points! I'm very excited to see what Moltex has to bring!

[@davidcampbell1420]

@@greggolding2291 They need to hurry up. Darlington is going to get mothballed soon. Ontario cant afford to move backwards on green house gases.

[@CUBETechie]

If you use a U235 shoot an neutron on it you get the core gets unstable and split into Kr86 and Ba 144 and you have 2 neutrons which fly away and enter another Atom For example U238 and it turns into Plutonium 239. Did I understand it correctly?

[@TheNorang]

Thorium is the Future and that's where we should go

[@adlucem9845]

Actually fussion reactors are the future.

[@paulanderson79]

@@adlucem9845 Problem is that we have no way of sustaining a fusion reaction at this point in time.

[@Steven-sy3ye]

Hi professor, could you do a video about the gen4 terrapower reactor design?

[@alvaroverdion]

I'm not sure if we have 30 o 40 years to get VI generation reactors. The planet needs them now.

[@uploadJ]

The planet is just fine. The PROBLEM is the periodic HYSTERIA that overtakes MANKIND from decade to decade.

[@bhfourtwoeight7343]

My prediction in late 2020: More like 7-10 years before Gen IV plants are built one off, a few more years before they are factory built. 2035 common. There may be function prototypes of the Gen IV cores within 3-4 years. Supply chain development and custom construction should result in a working plants within 5-7 years. Factory scaling up will take another 2-3 years. Some timeline overlap likely. I'd guess 2035 at the latest for "off the shelf" plants. Gen IV's will start replacing existing fossil and retired nuclear plants. By 2030's Gen IVs will be replacing the retiring grid scale solar and wind farms.

[@Fish-ub3wn]

Professor, please run audio throug a filter to cancel out this screeking noise of your pen. It's disturbing. Otherwise great material.