Thanks for all the great comments and discussions in the comments - I have been learning a lot from reading them all. One common point is the use of helium-3, I probably should have mentioned it in the video, but the reason I did not is because I wanted to focus on the 'mainstream' fusion pipeline. The only company I have seen looking into this is Helion, which although is an interesting project, they are currently planning to create their helium-3 from D-D reactions, which I need to look into further. The other option is of course helium-3 on the moon, but I need to look into this more and it was diverting away from the key points I wanted to make in this video! Watching out for a future video comparing all the types of fuel we could use for nuclear fusion!

I had always understood that this was not a "problem". It was known perfectly well that fusion power would not be usable, unless we had fusion reactors that could use only deuterium as fuel. Current attempts at making fusion reactors with deuterium and tritium as fuel are only intended as a steppingstone on the way to building a fusion reactor that will actually be useful.

Yes, tritium breeding has to be taken into account when designing a fusion reactor, but it's not like this is some brand new thing that nobody thought about before as your title suggests.

I was worried at first that this video would be a grossly misinformed & fearmongering anti-fusion click-trap because of the title, but I have been pleasantly surprised. This is an extremely well-presented subject that presents the problem and its possible technological solutions. :)

I watch fusion related videos regularly and I heard that they experiment with different element combinations other than tritium (since it's so problematic). They mostly use it now in the *_test_* reactors because it's the most optimal combination (yet) and what they try to get working are (primarily) the reactors. If you have an reactor producing net energy using d-t it's a good sign this design might be good. But if you try to work with hard fuels directly it might never take of. It's like trying to run one of the first combustion engines with tanker fuel.

Tritium breediing does not have to rely on the fusion reactors, it can also be done using other neutron sources. It adds to the cost but is feasible. As for the Lithium 6, as soon as te demand is there the facilities will be uilt, just like with any other material. the process of enriching it is well understood and the fact that a site that was poorly run decades ago is no longer operating does not necessarily mean that the method itself is unsuitable. Other than that a good video.

Even if it's a no go, money in this kind of research is never waisted. It furthers our understanding of plasma science and provides us with new ways of thinking when it comes to energy production

I sincerely don’t get what the problem is supposed to be. We have enough of Tritium to continue researching the technology for the next couple of years. Should there be the need for more Tritium, for example because of D-D fusion appearing too far out of reach, producing it may be costly, but trivial when it comes to the technology. Neutron flux reactors are well understood and used in research all the time. Surrounding the neutron source with a blanket of heavy water, which is kinda abundant, will yield Tritium, as that’s just how it gets produced in the CANDU. You would not even need Lithium-6 for that. Should Fusion power be commercialised, more efficient methods of producing it, for example in Lithium blankets, could and would be researched. But until then you could probably come by by just firing neutrons at some heavy water.

I love how all the comments are completely destroying this video’s clickbait title/concept. I learn something new every day.

I just finished my Fusion Student days ( I guess I am more or less the same age as you) and I approached this video with my spider scam sense tingling... I did not know your channel... Well.. the scam sense was wrong... Good job man, this is a nice video with proper scientific backing data and sources mentioned. I do not agree with the background message that "they are not telling us" ... there are lots of papers focused on the breeding ratio problem... you also mention some of them... But I guess that youtube videos must have a catchy title and claim ;)... But still... a great video! My compliments! It left me with the thought that I may even be up to help you out on similar projects ;) In the meantime... Keep it up!

A good rundown of the key issues facing tritium production/consumption. However, there are a few issues I would like to point out: - Claiming that scientists are "hiding" tritium problem is not true (and frankly a bit dishonest). This is a well known problem with large volumes of papers addressing it and any introductory material to fusion technology points out this issue; - D+T reaction is not the only reaction possible (it is easiest to achieve) and it would be only a stepping stone towards even more sustainable fusion reactors. The video does briefly mention D+D reaction which could also be used to directly produce energy (requires higher temperatures hence harder to achieve); - There is quite an obvious solution to producing initial quantity of lithium needed for fusion reactors - tritium breeding facilities (i.e. a modified fission reactor). And even with the current energy crisis in Europe we might see a renascence of nuclear fission power plants, some of which might be designed with tritium production in mind.

Honestly, even if fusion turns out to be not feasable, I don't think it has been a waste. We learned so much from this project.

I thought you were about to talk about plasma disruptions and their irreparable damages to the hull. Or the fact that the hull is radioactive and will be hell of a challenge to fix. Or the fact that tokamaks are quite a dead end compared to Z-pinch but that one has curiously been ignored since the Sandia Labs exceeded 4 billion Kelvins 5 years ago, a temperature that could lend itself to the aneutronic bore-hydrogen fusion and solve both the tritium and radioactivity problems!

Just remember folks - the end of nuclear fusion could be only thirty years away...

The idea of a Lithium blanket that will produce tritium for the Deuterium-Tritium fusion is quite old. I learned about it in a nuclear engineering course I had, as an engineering student about 40 years ago. However the main problem was not the scarcity of tritium, but the protection of the reactor's components from the neutron flux of the fusion reaction. Neutrons have the tendency to make the material they hit radioactive and cause them to transmute in to led eventually. This, for a 24/7 year round power plant operation, would require a tremendous amount of service and parts replacement. The other serious problem with the Lithium blanket, besides the scarcity of Lithium 6, is the fact that Lithium is flammable and ignites explosively. This would mean that the slightest leak of air coming in to contact with the lithium blanket, under high temperature conditions and the entire reactor would go up, like an old photographer's magnesium flash. The best way to go with fusion would be the neutron free Deuterium-Deuterium reaction, however the starting temperature for such a reaction is at least 3-4 times higher than the Deuterium-Tritium reaction. This is a temperature level absolutely unattainable with current technology, possible maybe after 100 years at least. In my opinion, with current technology, the best way to go until a Deuterium-Deuterium reaction becomes possible, is the liquid salt Thorium fission reactors, that appear to be safer and with much less radioactive waste than current Uranium fueled reactors. Also Thorium is much more abundant than Uranium and there is no issue about someone making nuclear weapons though the Uranium enrichment process or the nuclear waste reprocessing that could provide Plutonium. PS. If I remember correctly, Alpha particles hitting Beryllium produce neutrons. At least this was the way our lab's neutron generator worked, by using a Plutonium-Beryllim core and we would put our samples around it. So in what you describe, they probably want to use the Alpha particles produced by the fusion reaction to maximize Tritium production from Lithium, by enhancing even more the neutron flux.

Together with the tritium self-sufficiency problem, there is also the not so evident but critical fact that tritium recovery and re-injection (done in the tritium plant) is not immediate. Given the low cross-section of the reaction, tritium burn-up ratio is rather low and most tritium (~95%) reaches the divertor without being burnt. This tritium, along with the bred one, must make all the way through the tritium plant and tritium recovery systems to be re-injected back into the chamber. Typical residence times in the tritium plant range from a few minutes to hours. So, during startup, a reactor will need enough tritium to sustain reaction during the recovery time (minutes at best), times 1/burn-up ratio (let's assume 95%, so times 20). That's a lot of tritium (tens of kilograms) needed beforehand, and just D-D breeding might not be enough.

I saw an article about the discovery on the moon of rocks containing Helium 3 which was mentioned as a way to do fusion without emitting the troublesome neutrons. Since what we are really interested in is heat it would seem that this Helium based reaction would greatly simplify things. I don’t know why that isotope exists on the moon (and not apparently on earth) but I’d be interested in your comments on it.

This is known and has been known. The large neutron flux was to be used to breed tritium. One method is using lithium blankets just behind the walls. The other well known issue is that the reactor materials become highly embrittled and radioactive. I learned this and far more in the 1980s. Of course if the pico second terrawatt laser shot used for lithium - proton fusion works as a reactor all these issues are avoided.

The way forward seems to me to be that once sustained DT fusion is achieved we need to push forward and continue increasing the achievable temperature and confinement to the point where D-D fusion becomes self sustaining and thus do away with the tritium requirement except perhaps for starting up more easily. D-T fusion has always seemed to me as merely a prototype that is the easiest possible form of fusion just to get us started. Once ITER is running a self sustained fusion it will teach us a lot about how to optimize the confinement performance meaning we will be able to achieve the same type of fusion with a smaller device and/or achieve a much harder type of fusion (D-D) with the same size of device.

One comment, well after the fact. When someone puts "shocking" in their video title, that's most likely going to get ignored. Too many people are getting too dramatic with their titles and thumbnails, and it really detracts from the YT browsing experience. I'm not looking to be shocked. I'm looking to be entertained, engaged and informed. Your stuff is great, Ziroth - I really enjoy learning about interesting new developments in engineering, watching the science fiction of yesterday becoming the reality of today!

Your channel is the first to introduce something new to fusion that I have yet to hear about

I'm not a fusion subject matter expert, but I would like to add that the US government has a Tritium research and production facility at the Savanah River Site in South Carolina. It's just one part of the site, and it's primary function during the cold War was nuclear weapons production. Although you need a DOE Q clearance (top secret) to work there, there are thousands of such employees on the site. As such you can read job descriptions on job postings and get a good idea of what they do without actually having access to any classified documentation. Though we aren't currently increasing the number of weapons in the stockpile, they are producing new ones to replace older ones. It may be too expensive to make sense for fusion, but there is certainly a lot more than 25kg of tritium, it just isn't on the "commercial" market. The Savanah River Nuclear Laboratory lists fusion and Helium-3 research in many of it's descriptions for research scientist and engineering job positions so they are definitely involved in some sort of research to that end, not just weapons. Maybe there will be a crossover one day, and the Tritium housed for weapons could be used for fusion. Source- I live in the city beside SRS.

Nuclear fusion is hard. Nuclear fission is easy. Both need radiation shielding and other safety measures but the latter is cheap. Fast spectrum molten salt nuclear is intrinsically safe. It removes all of the inherent hazards caused by any other technology. That makes it cheap. The fast spectrum means no long term waste. Everything gets burnt.

Well, there's a false premise right at the beginning of the video. The deuterium-tritium fusion reaction may be the one that has gotten the most attention. It is the most attractive candidate to work, which is why ITER has chosen it. But it's not the only possible fusion reaction available. For example there is deuterium-deuterium, deuterium-helium-3 and proton-boron-11. At least those are the ones I've seen suggested before, and I seem to recall that there was someone just recently suggesting using proton-boron-11 in a test reactor, but I don't remember which company it was. There are advantages and disadvantages with all of these. The problem with Helium-3 is that it is also a very rare material, but it is possibly quite abundant on the surface of the Moon, so if we get a mining base up there, then this may well be a good solution. Because of the extreme efficiency in fuel spent per energy produced, it can actually be feasible to have Moon mining for this as a fuel. Proton-boron-11 requires extremely high temperatures (gigakelvins), but it doesn't produce neutrons, which reduces or removes the problem of activation of the reactor housing material, as well as neutron radiation damaging the reactor directly. But the billion-degree plasma is not an easy thing to deal with... not that the million-degree plasma of D-T is "easy" either. I have no impression that this is "shocking" nor being kept secret by anyone, nor is it a big "news". The problems of creating, and handling, tritium are well known. In fact, all variants of hydrogen are notoriously difficult to deal with. Just look at all the trouble NASA is having with the hydrogen on their SLS rocket. Even though they have more than fifty years of experience in dealing with cryogenic hydrogen, they still struggle with keeping it where it's supposed to be and preventing leaks.

The main problem with fusion (outside it not being anywhere near operational yet) is the cost. No one's been able to show if it's going to be viable or not. These reactors are extremely expensive and wear down pretty fast

Super informative - thanks for explaining a complex problem so clearly :)

One other little problem…materials must be developed that can withstand highly energetic (14 MeV) neutron bombardment. Those high energy neutrons will knock atoms of the first wall off their lattice sites. This creates vacancies and the vacancies coalesce to form voids. The end result is void induced swelling. Components will grow in three-dimensions and will lack stability. This was a large problem in our fission breeder reactors that produced fast neutrons of only 1 MeV energy. The fuel was lifetime limited by swelling of the structural cladding and fuel ducts. Within a year of operation volumetric swelling amounted to 16%. This swelling has to be accommodated by allowing the reactor core to move. Fusion reactors, with their much higher energy neutrons will need to accommodate some swelling in the first wall. Excessive swelling will require replacement of the first wall which will be complicated due to it being radioactively activated by the neutron bombardment. Vanadium and Vanadium-chrome alloys resist swelling, but there likely isn’t enough vanadium in the world to service manifold fusion reactors.

there is something people should know that money spent on big scientific facilities are not wasted even if projects fails to achieve its goal because of the technologies that come out during their work towards targets which can be commercialized and open new industries and opportunities and this kind of technologies private sector will never ever take the risk and spend money in

All those problems are not a problem at all. What stops us from getting fusion is the problem of high pressure and high temperature. If pressure is too low, then you need higher temperature, so atoms have higher chance to bump on each other and merge. Current problem is to build a container, which can hold a very hot plasma (problem with the cooling) under a very high pressure (problem with strong enough material). Next big problem is with pipes which delivers fuel and energy to starts the fusion. I think that the first commercial fusion reactor will be very deep under water in the ocean (like in a drilled hole in the Mariana Trench). That way it will get cooling and additional pressure from the water (to keep reactor intact) and fuel from Deuterium in the water.

Tritium production is considered an undesirable effect in molten salt reactors.

Never thought of this, very interesting. And absolutely amazing job on the video mate!

I have to congratulate you, I LOVED TO WATCH YOUR VIDEO, all the information, the research, and the editing, ALL great, thank you for sharing this with us all 👌👌

I remember when we were only 10 years away from nuclear fusion. Then, 10 years later, we were 20 years away. Recently, we were only 30 years away. It’s like that dream where you are running down a hallway that keeps getting longer.

If that were the only problem with fusion we could solve it by building more fission reactors to breed tritium. The more serious problem is that fusion is nowhere close to energy break even.

You are spot on my friend. This will be one of the most challenging aspects of adopting any DT system, if and once the burn method essentials become mature. While not a shocking problem -as your quotation of certain authoritative journals, and a long-history review of the field would show - it seems to be the one issue that, to me, stands a chance of really hamstringing the evolution to actual use. It may be so bad in practice that we may be seriously forced to take more in interest in "exotic" cycles like HB11 (now just getting significant funding). Many thanks for a well researched presentation - will send my students here! I wish you a great career ahead!! regards D Barillari (nuclear physicist and on-time CANDU specialist)

Well the short term solution seems obvious, build more fission reactors to support the fusion reactors. I see no problem with this. We can create a looping system where the byproducts of one fuels the other.

as a person who is writing a paper on fusion reactors and has encountered countless clickbait fusion reactor videos during research I thank you for making a very well explained and informative video which doesn't dodge around the topic for 10 minutes just to mention the actual thing in the last 30 seconds :)

Another possibility is hybrid fusion-fission reactors: use the fast neutrons generated by fusion to trigger fission in ordinarily unfissionable Uranium-238. Then use the neutron surplus from the U-238 fission to breed the tritium needed to continue the cycle.

I was tempted to “pre-empt” your video, but decided instead to listen right through. You are absolutely correct about the lithium breeding issue. It is an area that has had too little “investment” of technology and effort because the current strand of research is focused on - 1. getting stabilised plasmas 2. Establishing a “burning” plasma with all of the potential additional stability issues associated with a burning plasma versus a non-burning plasma. 3. Getting the required gain in thermal efficiency - I.e. more nett power out and than power used to establish the maintain the burning plasma 4. Running the plasma for long enough to be a viable producer of energy. All of which problems are still yet to be resolved. And until they can be, the next phase of a “production prototype” will not be financed by anybody. It is during the “production prototype” phase that the breeding issue will need to be resolved- alongside many very serious metallurgical problems that many scientists do not yet realise they are going to face. (or maybe, some do, but are deliberately keeping quite about these so as not to throw a spanner in the works of the development efforts). My personal opinion, for what it’s worth, is that these issues will hold up the introduction of fusion reactors for a longer period of time than that taken by the physicists and engineers to establish a burning plasma. But many in the industry think that taking the energy from a fusion reactor will be as straight forward as doing so from a conventional nuclear fission reactor. Technology which is well established. Again, my personal opinion is that you are comparing chalk with cheese. But, on the bright side, I think the problem is a “nut that can be cracked” if there is enough investment in the research. ITER may provide a number of answers - but to be honest, I think that ITER is now as much a costly white elephant which is diverting money that could be better used elsewhere - as far as fusion research is concerned. Again, my opinion, is that nuclear fusion will be solved and developed by private initiative - not through a project such as ITER. There is much evidence that this is happening already.

If you think about it mining minerals in space can just solve all these rare element problems

I think that the main reason the supply problem isn’t addressed more often (and is kind of elided) is because just on its face nuclear power (both fusion and fission) face large amounts of popular opposition. Evangelists want to boost enthusiasm for the tech, and you don’t get effective boosts if you front-load these concerns. If we ever want to see nuclear power become a replacement for fossil fuels we need to get the public on our side, and “we’re still addressing some issues, but those are solvable and the process is still very safe” is about as far as most people need to hear for fusion. Fission is more tricky, and requires more education, but that’s just because of the high profile disasters.

So I'm a roofer, not a scientist, no degrees, not a single minute spent in a university science class. I have a passion for fission technology and therefore learned how breeding works. Then one day I noticed the tritium problem, because I learned probabilistic neutron flux rates for breeding in fission. So just saying a layperson builder with an internet connection could figure the tritium problem out on his own. No science journalist has any excuse.

Instead of spending billions of resources on fusion that will perpetually be 20 years away, people should concentrate on MSR fission (LFTR).

A most impressive video. This is the first of yours I've watched and I've happily subscribed.

When I was at school a physicist dealing with functional analysis in physics came to give a short lecture to encourage us to pursue physics education after school. Among other things he said he's dealing with approximate stochastic equations - ones in which by definition a concrete solution is impossible only a probability approximation. And he said that thermonuclear fusion at scale is described by one of those. The obvious problem, he said, was that since that was the case - it's pretty much impossible to build a reactor and be sure it won't just explode at some point... wiping pretty much all life on the planet. I'd say that might be a bigger problem...

There are a couple of solutions. The first one is to use hybrid fusion reactor with more efficient neutron multipliers (fissile materials like minor actinides or plutonium), then this neutrons could be used for tritium breeding. The second one is to create special fission reactors with lithium rods (but this option seems less atractieve for me).

This is an excellent account of some of the issues facing tritium breeding, but one could add the problem of tritium escaping the reactor. This seems inevitable given that the tritium will be bred from lithium based material in a hot environment and that adequate tritium diffusion barriers do not exist. Even the relatively low tritium levels in the Canadian Heavy water reactors give rise to tritium loss to the atmosphere.

Maybe you addressed this in other videos, but one important missing point is that for the moment, the fusion reactors that are imagined, do not contain any device or mean to recover energy; while it is the main target of the fusion process, for the moment there are no plan to recover the heat, produce water vapour and make a dynamo turn. Since the heat is maintained in a magnetic levitation, the fusion is "wireless" and do not touch the walls, so how do we recover the heat ? Is it only by radiative transmission ? The main challenge include PRODUCING heat to start and MAINTAINING heat to continue the fusion reaction, but to produce energy you need to tap into a store of excess heat. (that is the opposite)

If we spent the same money on storage research as we did on fusion research, we might have achieved something big by now. We have a big fusion reactor in the sky, harnessing the power is easy, storage isn't.

It has long been recognised that a fission reactor is needed alongside any fusion reactor to provide start up power for the fusion reactor and produce tritium. Several fusion reactors could be powered and supported by just a single fission reactor. The suggestion that fusion reactors will supply safe and radiation free limitless power one day is completely false. The radioactive waste products will be easier to deal with, and fusion reactors are inherently safer than fission reactors, but they are not risk free. Commercial pressures with result in corners being cut, resulting in excessive neutron flux leakage and the possibility of liquid metal explosions in under specced heat exchange mechanisms. Fission reactors are still going to be the dominant force in the safe generation of massive amounts of electricity with minimum emissions to the natural environment for the next 30 years or more.

It might be good to also be an advocate of thorium fueled molten salt reactor development because as you know it has significant advantages over existing fission and it has been tried and tested at Oakridge decades ago but research and development went in another direction. With todays urgent needs for green base load energy we should putting fusion on hold channeling development effort and funds into Thorium as it has huge potential to be available as an intermediate measure 'til fusion is available.

Only touches the surface of the many problems that fusion is facing rn.

For those without the "bring back youtube dislike" extension installed, this video currently has 11k likes to 5k dislikes. So maybe take this information with a grain or two of salt.

I remember the ridiculous hype of nuclear fission in the 70s - electricity was going to be free! New tech IS ALWAYS HYPE until you have it, then you know the true cost.

Please do a video about First Light Fusion: projectile fusion aka pulse fusion (not self-sustained). As I understand it can use deuterium only or both tritium and deuterium. Would this be feasible in your opinion?

good explanation of a problem that is not relevant and therefore is correctly not focused on by most fusion enthusiasts. There is simply something fundamental about plasma behavior lacking in our understanding atm. We are not close enough to a breakthrough in fusion that will make this problem relevant. But when we get there, I suspect this problem will be way easier to solve than our current problems

Deuterium+Tritium is not the only way to get fusion. It's the easiest, that's why it's the one used in nuclear bombs, but that extra neutron means you have to get extra careful with materials surrounding the fusion core - and eventually, most those materials will get radioactive, which compounds the issues. It's far simpler if you go with helium-3, or forget that and concentrate on deuterium+deuterium reactions, although these last ones require higher pressures and temperatures release much less neutrons as by product

So...fusion is still 30 years away? Nonetheless, fusion research has been remarkably successful. At generating research grants. We can (and have) spent our money on worse things.

What about helium 3 ?

I used to love the idea of fusion. But even more than the isotope supply issues here, the greatest obstacle is practically dealing with the huge neutron flux coming from the reactor. It will quickly degrade and transmutate all the reactor structures and will leave them insanely radioactive ... hard to maintain and lots of radioactive waste. The ability to get the heat from fusion and turn it into usable energy (i.e. steam for turbines) is not close to being solved.

Now take a look at all the material science issues remaining to be solved when it comes to the hard neutron radiation inside the tokamak. It's another of the many "may be solved some time in the future" issues surrounding nuclear fusion.

Add to that the fact that tritium has numerous other uses in industry - the insignificant annual supply is already used up for things that have nothing to do with fusion. The simple basic truth of the matter is that fusion will fail simply because it is too expensive. To meet humanity's future expected energy requirements we will have to build dozens if not hundreds of actually functioning ITERs. Unless we have some magical 24th century Star Trek-like economical transformation, EACH ONE will still require the combined resources of several first-world countries. It's just not going to happen.

I am not sure why you are assuming Li 6 is required for fusion. 　　n + Li6 → T + He4 + 4.8 MeV 　　n + Li7 → T + He4 + n - 2.5 MeV As you can see, Li 7 is required to achieve > 1 tritium regeneration.

Hit the nail on the head with this video. I'll give my own input. 1/ There are a few massively funded projects currently happening. They're operating like massive Go Fund Me's except they've effectively become massive black holes for money. Fusion reactors being one example and particle colliders being another. Effectively they've become distant from their original intentions and instead now appear to massive PR teams working for a way/reason as to why they should exist - like biased statements and known things that cannot be done (they know fine well) but know that money will come to them if they give enough convincing bull sh**. Nuclear fusion being ten years away - for the past 30 years for example. 2/ You've mentioned it here - such reactors, if they would ever work, require 'spicy' ingredients. Spicy as in non-standard isotopes. Isotopes that are made within nuclear reactors. (you'd almost think that governments are creating reasons as to why filthy dangerous currently operating nuclear reactors are still needed - in the mean time another byproduct is nuclear materials for bombs..) 3/ I liken fusion reactors to that other non-starter called thorium reactors. I'm sick to death of trying to explain to clueless individuals spouting to me how thorium is the way forward when in fact these same people would struggle to understand personal hygiene. Thorium reactors are a very old nuclear technology. They're certainly not nuclear free - just like current day fusion experiments. Thankfully, way back when thorium research was done they realised that it was a non-starter for energy and quickly abandoned that research. Today though, with fusion everyone has gotten greedy and won't let go of the idea. A good video for pointing out just some of the reasons why fusion will not work.

There is a design for a fusion power reactor that has been practical since the 1960s except that no one would want to build one. It involves creating a large concrete Dome and then exploding hydrogen bombs inside. The Dome would have to be really large and really thick but it would produce a lot of power. You would just use the heat generated to drive steam turbines. This steam might be a bit radioactive though. As I said no one would want to build one

I am 70 years old and have always been something of a "science buff". For as far back as I can remember fusion has been "just over the horizon". It's always just 20 years or so away. Were I a cynic I might suspect that the whole fusion chase is no more than a dodge; a con; a way to make some people rich.

Another problem also exist - degradation of superconductive coils in neutron flux. We can't stop all NF reaction neutrons from reaching coils. For ITER it is not big problem because it active NF reaction will be counted hours per year at best. But for hypothetical commercial NF reactor with GW output working 24/7 neutron flux will destroy coils for time less than year.

As I have understood it, the fusing of deuterium and tritium is easier than other fuels and this is why it is used. What People seems to misunderstand is the fact that ITER and other big projects only are plattforms to get a proof of concept... the real fusion-powerplants Will sadly not Be up and running any time soon. We can only hope that the existing tritium is enough to set us on a path forward...

You can also fuse Deuterium with Lithium-6 to produce 2 Helium atoms. In fact, this method is often used in hydrogen bombs using Lithium(6) Deuteride instead of the Deuterium-Tritium mix which loses potency over time due to the short half-life of tritium.

Scrap fusion research and invest in fission

This video seems to fall into the common "science vid" trap of being perfectly fine, but with a way overblown, clickbait title that ruins the quality. Glad that comments are pointing out the not-so-shocking nature of current fusion developments.

The solution seems fairly strait forward, people just don't want to hear it. More Fission plants. Not only do Fusion plants need a large amount of tritium that can be produced in them, they also need a large amount of power to "jump start" the fusion process (even assuming they get the power output to positive, this will still be true). Current generation Fission plants are much much safer and produce less waste than older models, but almost none are operating due to fear of nuclear power.

Is there any particular reason we can't build more tritium-breeding fission reactors, as either a temporary stopgap while getting better fusion breeders online, or even as a permanent solution? Yes, fission reactors are less safe, but unlike with a reactor intended to power a city, which you'll want to be somewhere in the general vicinity to minimize transmission losses, this kind of reactor could be placed in the middle of the Gobi Desert or something with only minor efficiency losses considering the energy density of the product. That would automatically make it safer than any coal plant in history.

My intrusive thoughts wondering how many revolutions I could get on a fidget spinner while sitting in the middle of that pretty glowing donut thing

See “The Trouble with Fusion” by Prof Lidsky 1983, MIT, covering the tritium fuel problem and much more, circulated widely in fusion circles decades ago. “One of the first issues posed by the D-T fusion reaction was how to supply suScient tritium. Tritium is radioactive, with a relatively short half-life of 12.4 years, and therefore it exists only in minute quantities in nature. Luckily, the neutron emitted in D-T fusion can react with an isotope of lithium to produce tritium…” “…Lithium itself poses serious engineering prob- lems. It is an extremely reactive chemical: it burns violently when it comes in contact with either air or water and even capable of under- going combustion with the water contained in concrete. The lithium may be either in liquid form or in a solid compound. Liquid lithium blankets produce substantially more tritium and allow it to be more easily removed. How- ever, the need to handle large amounts of this metal in liquid form leads to technical com- plexity and poses safety hazards. The tritium-breeding region has other engi- neering requirements. It must be designed in such a way that the structural materials, as contrasted with the actual lithium, capture a minimum of neutrons. Also, the operating temperature must be high enough so that the coolant, when piped outside the reactor, can generate steam eSciently. Outside the blanket, powerful magnets must provide the magnetic fields to contain the plasma. These fields will exert enormous forces on the magnets themselves, equivalent to pres- sures of hundreds of atmospheres. If made from copper wire, these magnets would con- sume more power than produced by the reac- tor, so they will have to be superconducting. Superconducting magnets, cooled by liquid he- lium to within a few degrees of absolute zero, will be extremely sensitive to heat and radia- tion damage. Thus, they must be eFectively shielded from the heat and radiation of the plasma and blanket. Temperatures within the fusion reactor will range from the highest produced on earth (within the plasma) to practically the lowest possible (within the magnets). The entire structure will be bombarded with neutrons that induce radiation and cause serious damage to materials. Problems associated with the in- flammable lithium must be managed. Ad- vanced materials will have to endure tremen- dous stress from temperature extremes and damaging neutrons. The magnetic fields will…” In the 40 years since, no prototype work has been done to resolve the difficulties w T production. As said, it’s expensive and requires all kinds of permits to handle, which is why most reactor tests are done w inert gas. When and if fusion becomes viable, expect to see a wave of proliferation scare tactics about how T enables hydrogen bombs.

Thank you. I graduated in physics in 1973 and was interested in fusion then as a career. The JET project then estimated 30 yrs to commercial scale. - ie 2003. In 2005 I met a new physics graduate who had the JET information - it still said 30yrs. The problem of tritium creation was well known then. Unfortunately, some scientists ignore the facts before them when lured by the funding and dreams of immortality (the person who made fusion happen). They happily pull the wool over the eyes of politicians and the public who have insufficient scientific knowledge to critique the scientist. While the world faces real dangers on energy, environment, food supply etc, far too many of our best physics brains are playing games like this, the LHC looking for bosons, dark matter/cosmology, space travel etc.

you forgot to expand on the biggest main Issue I find with fusion as it stands, and that is that it requires temperatures several times the sun's own to operate. This is an issue because the energy in is far greater than the energy out without matching or exceeding the pressure of the gases making up the sun's fusion process. This means that as it stands, it is very energy inefficient by design since it would be quite unsafe if the pressure was artificially done to the required level. Feel free to correct me if I'm wrong, I'm not an expert on this specific topic and just know a bit about fusion.

"In any system of energy, Control is what consumes energy the most. No energy store holds enough energy to extract an amount of energy equal to the total energy it stores. No system of energy can deliver sum useful energy in excess of the total energy put into constructing it. This universal truth applies to all systems. Energy, like time, flows from past to future" (2017).

Fantastic video, got yourself a new subscriber! One more question: I’ve heard speculation from some astronomers that the moon may have large quantities of tritium in its surface. Is there any validity to this claim?

New breakthrough!

Fusion cannot work profitably in earth gravity. The huge mass of the sun packs hydrogen atoms so tightly together they fuse. Gravity is the input of free energy necessary to the 'perpetual motion' of fusion. Without massive gravitational forces, it's necessary to pump absurd amounts of energy into the system to cause fusion to occur - and when all is accounted for, this energy input will always be greater than the useful energy one can extract from the system - because perpetual motion is not possible, however complex the machine.

we could also just keep up fission reactors until we have done enough research for fusion. if there are any questions about the waste: it can be used to get even more power without any leftovers at the end. the reason that isnt used is because the bad connotation of nuclear fission, we cant build new plants if it is stopped on all sides and so we cant build better plants to use those better waste solutions.

To be fair you can, fuse anything up to iron(iron being you end product and theoretically have a net energy gain. The limited supply of tritium isn't much of a concern. Tritium is probably the easiest to figure out (though even that is debatable) but seeing as we have fused things where the end product is element 118, I think we will be fine.

There is no problem with nuclear fusion, there is a problem with the old tokamak concept, where we spend most of the money! We should invest into different newer fusion concepts. For example the two-laser picosecond Proton-Boron Aneutronic fusion. for example the DPF (dense plasma focus fusion). There is no Tritium needed, no neutrons from prime reaction, no neutron radiation, no radiactive waste and you can direct conversion into electricity without boiling water, making steam and use a turbine with generator.

We've been making stuff with neutron bombardment for ages without fusion reactors, fission reactors produce tonnes of neutrons too. These tritium breeding blankets seem like a complicated and expensive way of doing something that can easily and cheaply be done using other methods.

Tritium is currently not stockpiled because it decays. Once fusion reactors come online, sources of tritium will come up pretty quick: Distillation, nuclear waste, etc

Are the Tritium products on Amazon different from the Tritium used in reactors?

Just " always " 20 years more. It's a fusion myth for now . Wild goose chase .

Seems kind of a waste to put this much energy into a dubious energy source. Fission works; renewables work; both are known quantities. Fusion research has been going on for six or seven decades and may take just as long to become viable.

If I understand correctly, ITER and most fusion reactor research is based on methodologies that fight the nature of plasma. LPP Fusion is the leader in fusion development due to a methodology that harnesses the nature of plasma, rather than fighting against it.

Fusion scientist: Business case, I don't need no stink'n business case!

progress is never without it's challenges, the only tragedy is that so many is willing to give up on progress

John Keely machine shop work during late 1800's was able to control some forces of nature with resonance vibrations. He used arrays of tuning forks hooked to what we now call thermocouples and thermopiles of silver, gold and platinum wires. Inharmonics of certain RATIOS applied would cause molecular and atomic attraction. He could even cause same poles of magnets to attract. several books available. Keely And His Discoveries, + Free Energy Pioneer + The Snell Manuscript - which is a tech summary of Keely's 3 reports printed about 1892.

Tritium supply is a minor issue - when compared with the other beasts that the fusion industry is tackling. This includes first wall issues, plasma control, power supplies, heating methods and diagnostics. You need to separate problems that are limited by the laws of nature, from those that arise because fusion has been chronically under-funded. Bare in mind that until just recently, fusion has not received anywhere near the amount of funding that it is now receiving. A real sea change is occurring; and we've always had people who have said that this is impossible. We will continue to have naysayers --- even as the fusion industry continues to roll forward and succeeds.

Fun fact: Li-7 can also produce tritium if bombarded by energetic neutrons. This effect was discovered when the Castle Bravo test yielded an explosion three times larger than estimated. The package used LiD enriched to 40% Li-6. The scientists thought the remaining 60% Li-7 was inert, and accordingly calculated the estimated yield at 5Mt. Turns out, they were incorrect about Li-7 being inert, and wound up getting a 15Mt yield.

238 - 235 is three atomic units and solving that problem was huge. How much worse will be extracting 6Li from 7Li? There is only one atomic unit difference between the two. Additionally, we have been investing in and doing our best to create a fusion reactor since 1953. That's right -- 1953! That was 69 years ago. Are we to keep struggling with this until we have put in a solid hundred years? In my opinion fission is the real answer, especially when thorium is used in a LFTR type reactor. Just thought I'd give everyone a dose of reality.

This really puts the Fukushima tritium scandal into perspective. If there was even a remotely environmental consequential amount of tritium in that water it would be like just shovelling billions of dollars into the sea.

I can remember way back in 2037 when the first fusion reactor came online. There was a couple of years when they weren't sure if it would be a sustainable technology because of tritium availability. Then they discovered how to mine it directly from comets, and since then it has never been an issue. We still haven't solved the deuterium only fusion reactor though! We pay around 200 credits a year now for our energy, its a utopia!

People disliking this video should watch the entire video. They're making lots of really good points with evidence

2:45 Forgive my ignorance, but Half life of 12.3 years doen't mean our supply decrease by half every 12.3 years, it means radioactivity decreases every 12.3 years. That's a slight difference.