i believe Canada offered this technology to india in the 70s

I like a good fusion reactor.

@@LinuxLuddite Yep. India, Pakistan, China, Romania, and a few other places.

Hi Elina. Engineer from Canada here. I worked with CanDU reactors in nuclear safety for 15 years. I really like your channel and how you're making technical knowledge of nuclear reactors accessible to the world. Well done. You mentioned that Canada has an abundance of natural uranium and heavy water, which is why the CanDU reactor is particularly suitable to Canada. My understanding of how the CanDUs came to be here is somewhat different. Heavy water (D2O) isn't really a natural resource at all. It's a trace component of all water on Earth. Canada had a specialized part in the Manhatten project where it isolated heavy water by the energy intensive process electrolysis. After the war, there was heavy water on hand and a policy of non-pursuit of atomic weapons. Consequently, Canada began researching and developing reactors that could use heavy water for its neutron efficiency to permit sustained critical reactor operation minimal enrichment of fuel (eventually no enrichment). Several development reactors were built with light water coolant and heavy water moderator. As we got better as conserving coolant, precious heavy water was used as the coolant as well. I think the void coefficient on those light water cooled/heavy water moderated reactors must have been wild! So there you have it: Canada took the CanDU route to leverage its existing D2O asset and to distance itself from atomic weaponry while developing a nuclear power and isotope production technology. As the CanDU fleet scaled up, there was a need for more heavy water and mass production plants employing a chemical equilibrium reaction were built. After some decades of operation, the industry had become so efficient at conserving heavy water that the supply on hand is expected to last for generations. Much D2O is now on loan to a neutrino observatory deep underground. Those D2O plants were demolished, and we no longer produce any. You are quite correct that our domestic stock of expertise has been essential to continued operation of CanDUs. The seed for the workforce was planted as a war measure. The generations of people who have since dedicated their careers to those machines have made them highly beneficial in the long run, but that workforce doesn't develop suddenly just because a country decides to spend money. Having attended to those reactors myself, I've gained an affinity though I can see how other nations might be discouraged by all the novel moving parts.

I learned a lot about the CANDU reactor type indeed however it would be interesting to see how it compares to gas cooled reactors as well.

I was a sad day when the Arrow was cancelled but you guys in the US benefitted when the engineers and technicians left that project and played a HUGE role in the US space program.

@@Snowdog070 there is a 60% scale flying replica avro arrow being built and designed in Calgary Alberta at the avro museum

@@Kraigthecanadian At the Springbank airport.

@@threeparots1 oh yes that's the airport name but its in Calgary and most who know anything about Alberta likely knows where Calgary is

Sometimes, we CANDU things right in Canada.

I was able to see Wolseong #3 up close a number of years ago. IIRC they closed the tours at the Pickering NPP. No problem, I flew halfway across the world and saw one anyways ;)

I think the USA has lost the ability to make large pressure vessels. When we decided to replace the reactor heads we had to buy them from Japan because they could not be made in the USA. There is no foundry that can produce something that large in the US. If you don't use it, you lose it.

hmm... multiple channels, that phrase sounds vaguely familiar ;-)

I'll have to see an illustration.

@@davidhomer78 You nailed it sir/madam! I think JSW is the only one left .... I thought there was a place in Europe that forged them in the '70s but can't remember who ... or where.

Check out Osama's channel. He's a Canadian nuclear engineer and has a lot of CANDU content. www.youtube.com/@OsamaBaig

I was able to take a tour of one in Wolseong, ROK. It was interesting to see the 60s Canadian manual for it on display there, among a sea of Hangul :D. They were building two LWR (probably built by now lol) and the guide explained that the remaining spent uranium from the LWR will be finished off in the PHWR. It was a pretty sweet tour, you had to sign up for it to win it, and my gf at the time kept entering my name till she got us in.

Same here too as canadian, It's quite satisfying to finally know the basics behind this enigmatic candu reactor and the hype really worths it :) Thanks for this fabulous video!! knowledge acquired

@@MrStarmat You could have just went to a foreign national's museum showcasing the tech like I did, 10 years ago :P

Thank you for pointing this out as it was missed in the Video and is one of the ket structural safety advantages of CANDU.

Where did you grow up? My grandfather’s farm was in Underwood.

@@michaelbradley6175 Kincardine, but my mom grew up in Underwood.

Natural Uranium can sustain a chain reaction, but only in the presence of heavy water.

the heavy water just does the moderating not the cooling. cooling happens by light water circulating through the core hence CANDU reactors have a positive void coefficient if light water coolant is lost. in that case the heavy water is more easy to manage than graphite though as it won't catch on fire.

Perhaps it will have value for initial research but the production rate is too low to be meaningful as a fuel supply. Half life is around ten years so we can't even keep it in a bottle waiting for a fusion reactor.

​@@adamgavey1028 Viable fusion will need a C rate of ~10 and tritium neutrality. In an ideal world if we are 30 years from viable fusion we will need tritium produced to start reactors and perform research. More Candu reactors are key to this and perhaps short lived Candu SMRs with a ~10 year life may be a good way to generate it. Candu SMRs are in development. Without something we will never achieve fusion due to being supply constrained (in addition to the many incredible engineering challenges).

Very good point, and I would add It is an identified concern that the scheduled decommissioning of these CANDU reactors presents a limitation for future fusion research. It is surprising to me that so little effort has been focused on validating that breeding tritium from lithium is actually viable for fusion power generation.

@@ccibinel Agreed, Li6 blankets for breeding Tritium seems to be one of the only viable options. Fusion has a long long road to hoe.

@@Pnote2000 Actually, one of the key mission ITER is to test tritium breeding. To me, it seems like one of the easier problems to solve in fusion. I think you also need the 14 MEV neutrons from fusion to test in real conditions so it is very dificult to test without a large fusion machine.

And now Darlington will be producing Molybdenum-99!

Whats the use o cobalt-60?

@@joaquimbarbosa896 Treating cancer, and sterilizing food mostly

The Cernavoda NPP does not have a pressure relief building. Not every CANDU station has that building. 😁

I think that the only ones with a vacuum building are the sites in Ontario having 4 or more reactors sharing a vacuum building. The single unit in New Brunswick does not have one.

You are correct.

This is not new. Russian VVER 1200 and VVER TOI use SAOZ (САОЗ) tanks to fill the reactor with borated water, which is simpler in principle, because everything is contained in a containment along with the reactor.

I am from Cernavoda and people in the city are still waiting for Units 3 and 4 to be built many years after Unit 2 was put in operation. (let's not talk about Unit5) The politicians seem to just run down the clock until the first two units close and then back to burning coal it is I guess. :( I mean, we have 11 hydro power plants already built 98% and we just aren't using them. Goddamn expensive imported electricity seems to be very tasty.

Hah I was in Romania 3 years ago and I did not know this! I would have gladly taken a tour (if they do them) when I was there.

@@cezarcatalin1406 I am from Arad. Not only that, but from what I have heard, we have natural uranium deposits but we import uranium because our processing plants are shut down. Lovely country to live in :)

@@alexandrufrateanu I mean, you can be sure that if the socialists wouldn’t’ve built most of the current housing and infrastructure Romania relies upon nowadays, all the neoliberals after 1990 would’ve never even attempted it themselves. They can’t even build roads right (compare Transfăgărășan with Transalpina or “Transrarău” and let’s not forget the Brașov-Orăștie highway that crumbled in 3 months) and even when it comes to maintaining the old infrastructure they constantly fail (the “repair” job done at Unirii passage in Bucharest where vans constantly get stuck and the surface road started slumping into the concrete construction below).

How can you say Ceausescu was paranoid for not being dependant on foreign countries? This is a good thing and he did well. Should we put him down for everything?

Thanks a lot for the comment ! I appreciate it and I’m glad the videos were informative enough that gave you all the necessary info to make your own decision on the topic!☢️👩🏽‍🔬

@Richard, You hit the nail on the head. Global eduction is perhaps the biggest hurdle holding back nuclear energy. It's awesome to see that you had a curiosity to acquire knowledge and facts about nuclear, and that it changed your opinion on it. 👍

indeed, that was a fail from Elina. Online refueling is indeed a good way to make weapons grade Pu in a "water reactor",while generating electricity no problem. In a PWR you can also do it, but why would you? Just use HEU.

Yes that was a jarring misstatement for me too. The whole "D2O is a better moderator" line is a bit of a furphy, it's not the moderation but the lower absorption rate which allows a CANDU to have a neutron economy able to support unenriched uranium as a fuel.

@@sjholmesbrown Exactly. And historically that was the reason why Werner Heisenberg in Germany decided to use Heavy water for the experiments, since regular water didn't fit the bill. In terms of moderation light water is better, since the proton has the same mass as the neutron while the deuteron has twice the mass.

I was hoping someone brought this up. I hope more countries buy CANDU reactors, but we should be realistic about proliferation

The German Wikipedia article on CANDU reactors actually mentions that this reactor type is especially suitable to generate plutonium: "* die Bauweise als Druckröhrenreaktor. Sie erleichtert technisch den Bau solcher Reaktoren und erlaubt zugleich eine relativ einfache Gewinnung von Waffenplutonium, da im laufenden Betrieb Brennstoff zugegeben und entnommen werden kann." -> "* the construction principle utilizing preasured reactor pipes. It makes building such reactors more easy technically, at the same time it allows for a realtively simple creation of weapon grade plutonium as nuclear fuel elements can be added and removed at any time while the reactor can be kept running"

Yes dumping the moderator would stop the reaction but poison injection where a neutron absorber is injected into the moderator acts much faster and is what is used.

Also, since heavy water is necessary for the reactor to work, any overheating of the fuel will boil the water, removing the moderator and stopping the chain reaction. Plutonium is actually produced, but for the weapons-grade stuff you'd need to irradiate each fuel assembly for a suspiciously short time which would produce very little electricity. The whole world would immediately notice your weapons program and stop selling you uranium.

You can hot swap floppy drives in any computer (that even has them still) FYI... Maybe not really "hot" as they only use the power when reading or writing to disk, but you can certainly swap them with the computer fully booted.

Thank you for your comment ☢️👩🏽‍🔬 I am glad you found the video informative

Having such a different design can mean safety regulations are not appropriate or hard to apply. For example, most reactors have a negative void coefficient, meaning the fission rate falls when coolant is removed, but CANDU reactors have a slight positive coefficient. This is actually a very minor issue, especially when so many other factors and active safety systems have an effect, but regulations assuming a negative coefficient will disqualify a CANDU without an effort to change the regulations (which some people might regard as weakening them under corporate pressure).

the higher upfront cost and not being able to Make plutonium efficiently is two reasons why it’s not more popular

Can't make bomb byproducts. Hippie Canadians :P

Because it has few advantages. Basically, this is the cost of heavy water. Considering that France and Russia are massively enriching uranium for reactors, enriched fuel for light water quickly pays for itself. And also its complex design, like the RBMK reactor, only CANDU is also under pressure, which causes a lot of problems with pressure pipes.

@@nedward.7442 Heavy water is easier and cheaper than refining petroleum. The problem is that it is unconsumed, once you've made it you don't need to make more, and therefore has a small niche market. Enriched Uranium is consumed faster and is simpler to make a bomb with, hence a larger market. It is also less safe. All the nuclear disasters have been from enriched uranium facilities.

@@allanlank 1) What does oil have to do with it? How is heavy water production cheaper than recycling? This is a completely stupid comparison: a product that is consumed by the whole world, and a product that is needed only in narrow circles of production. 2) The bomb requires a uranium enrichment plant and the purchase of lithium 6, this will be such a large-scale production that everyone will notice it. Moreover, the main disasters did not occur due to enriched uranium at all, but mainly due to the incorrect design of the reactor and the carelessness of the workers (Chernobyl Nuclear Power Plant and Fukushima). How long has it been since your enriched uranium burns out faster? In reality, it’s just the opposite: the higher the enrichment, the longer the life of one company.

"Inspired" lol, such a cute way to say xerox copy of / logical evolution of the original cirus into a large scale colandria based phwr

props for still learning 👍

The CANDU reactor is about as old as you are, if not older. IIRC the first CANDU reactors had very little if any computer controls (I mean yeah they used TTL, but not full on computers).

If you're talking about the reactor at The University of Utah, it's actually a TRIGA reactor (much lower power and used primarily for research) and its on the engineering campus.

@@tedgood1224 , It's probably like you said for research but in Canada. :-)

@@test40323 It was actually a SLOWPOKE reactor, another type of research reactor, and is currently shutdown. Edit: you can have a look at the wikipedia article for SLOWPOKE reactors.

@@harryhall4001 , ah...you are right. My memory failed me. Thanks for the correction.

I think UT is the Universtiy of Toronto.

I'm not aware of any actual work being done on the CSMR. Do you have a reference other than the marketing materials? I know we're working on MOLTEX, ARC and BWRX licensing, but am not aware of any CSMR work actually being done.

Smrs are like free beer tomorrow signs at the local bar. Anything that runs a pressurized water system will require containment As the primary expense currently nukes must be big for economy of scale. Thorium Liquid salt and low pressure primary loops will make smrs a reality. Till then it's all flying car advertising...

There are books about this stuff, or take a tour of an NPP if you can.

Thanks for the comment ! Indeed this is a very cool feature ☢️👩🏽‍🔬

Glad it was helpful!☢️👩🏽‍🔬

😂

@@MitzvosGolem1 🤘☺️✌️

Unit 3 and 4 at Bruce A are using the same pressure tubes it was built with when they first came on line in 1977/78. They are prone to creep and have had to be 'shifted' at least a couple of times on Unit 3 (Unit 4 can float on both ends so not as big a concern) to compensate, but they do go longer than 20 years, at least the newer alloy that isn't as prone to delayed hydride cracking (the problem with the old tubes on Unit 1/2). Unit 3/4 were down for about 5 years of that total operational time during the infamous layup period before Bruce Power was formed and brought them back to life. So, other than maintenance outages, those pressure tubes have performed for at least 33 years or so of high power operation. If the tubes are not being replaced already, they will be soon, as they were several years ago on Unit 1 and 2. I retired from Bruce A a few years ago as an Operator, at the last in the Control Room as an ANO. Good job and a great overall reactor/turbine design.

@@frederickcwinterburn1837, Bruce plans to re-tube all the others. Unit 6 is nearly done and set to return to service this year and will be followed by 3 and then 4. Not sure about scheduling for the rest. Expected lifetime of the new tubes is 30-35 years.

CANDU reactors are terrible for proliferation as they avoid the whole enrichment step -- fuel it with unenriched uranium and it makes plutonium that you can separate chemically with no costly enrichment equipment. It also makes tritium just in case you feel like going thermonuclear.

Thank you so much for your kind comment! ☢️👩🏽‍🔬 I am glad and excited to have such platform to inform and educate the public 😊

tiktok is a platform for the spreading of mental retardation and insane ideas that will get you killed - don't watch that brain-cancer inducing platform, nothing good is there.

You don't have to worry. The US would never rely on another country, even their friendly neighbour to the north for their nuclear energy technology.

How did you model it? I'm assuming some kind of software?

Sounds like a school I’d like to do to ! In my school we learnt nuclear is lethal and we’re given the example of Chernobyl !

Damn we had Pickering NPP not TOO far away from us, they could have taken us there. What years were you in elementary school? I went in the late 80s, when there was still funding and interest (as well as pride) in this kind of stuff. FFS my middle school had a full on woodshop - gone now.

@@YourFriendlyNuclearPhysicist In Poland, they started Zarnowiec NPP, but I think Chernobyl had something to do with that project's stop. You sould talk about the Shoreham NPP - Long Islanders are STILL paying for that mistake, literally.

@@YourFriendlyNuclearPhysicist Just came across your channel. I grew up 1.5 hours away from Bruce Nuclear, largest CANDU plant in the world (8xCANDU 6 ~6400MW). Our high school physics class went on a tour during construction of the last 4 reactors in the '80s and could walk around inside the containment. I have touched the face of a CANDU calandria...lol Overall a good video, but a couple of questionable bits. 1) CANDU reactors don't have a pressurized "vessel". Instead the vessel (calandria) which contains the bulk of the moderator (D2O) is at atmospheric pressure and the individual horizontal tubes or fuel channels are pressurized. It is through these tubes containing the fuel bundles that the coolant (also D20) flows. Canada didn't have the ability to forge such large vessels and this is a design compromise that allows local production of reactors without that ability, plus it allows for online refueling as a bonus. 2) It is highly questionable to state CANDUs are more proliferation resistant. CANDUs actually produce more Pu than LWRs, but they also burn more. A typical LWR gets about 1/3 of it's energy from Pu Fission. A CANDU gets about 1/2 from Pu Fission. If the fueling cycle is followed, there is less Pu in spent CANDU fuel compared to LWR fuel (as % of mass). However and this is where the potential problem is, due to it's ability to online refuel, a nefarious operator can sneak fuel bundles in and out for short fuel residency times which is exactly what is needed for isotopically pure Pu-239 production. In fact, that's how the Hanford dedicated military production reactors worked (but with graphite moderator instead of D20). The reality is as you rightly exposed on your thorium video, if you have a reactor of any type, then you have a proliferation risk unless IAEA controls are strictly enforced. You should do a review of the MOLTEX designs if you haven't already. That is likely to be what eventually replaces CANDU plants in Canada. Overall great job...keep it up!

RBMK and MKER are already dead. They have the advantage that, with a certain design, they can also operate on natural uranium (the ADE-2 reactor, a producer of weapons-grade plutonium, could do this), burying CANDU. But their main big drawback is the impossibility of recycling, because... after the end of the life cycle, hundreds of tons of radioactive graphite and chlorine (a product of graphite processing) remain, so there is no other way out except bricking. it's under concrete. Regarding the production of plutonium, fast reactors cope with this much better.

Beautiful words that never come true. I'm worried that never, given Vogtle's experience...

I'm also a fan of MSRs but would like to see the NRC allow a liquid/molten salt fuel at least in some research/experimental reactors. We really need to be developing the next generation reactors now.

@@johnmason455 Concur!

I remember when some people from ORNL did a exhibition when I was in middle school. They brought among other things some of the uranium beads used for making the pebbles in this reactor. They were in a little glass bottle and as fate would have it when it was being passed around it got dropped, and lots of tiny uranium beads went all over the classroom. They swept most of them up, then we all got turns using the Geiger counter to hunt the rest. They made a game of it. We ended up finding all but 4 of them. Could only imagine what would happen nowadays 😅

@@christopherleubner6633 Uranium is laboratory radioactive, but very toxic.

@nedward.7442 in the form it was in, it was not an issue, the tiny beads were like mini jawbreakers that had a hard silicon carbide shell, a layer of graphite, and some a nice chewy uranium core. The beads were super tiny as well, about the same size as a pin head.