Why Don't We Have Nuclear Fusion Power Yet?

Published on Feb 6, 2019
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Fusion power is supposed to save us from fossil fuels, so when is nuclear fusion going to be a viable option and why has it been so elusive?
Hosted by: Stefan Chin
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  • i don't know about you but i've been powered by NF for a while us-tv.org/tv/video-efZ-8EbFWic.html

  • Power storage improvement will do more to stop pollution that any new power source. Storage is the key.

  • Because Financiers demand that Scientists predict their discovers, literally violating the process of science replacing it with the process of money.

  • #FundNuclearFusion

  • That 1 second hair cut at 9:49

  • this is cause they want to find a way to weaponize it as they did with nuclear …………a more powerful and cleaner source of power has excisted since the 50's

  • turbines ? all this work and we still cant find a way to get electricity more efficiently ?

  • The benchmark is producing energy at a cost that's equal or less than the current sources of energy. If you're spending billions to produce a few MW of energy, when you can spend millions to produce GW of energy, then fusion isn't worth it. I'm sure that one day we'll get there, but maybe in another 30 years ;p

  • In the meantime, Thorium nuclear energy: us-tv.org/tv/video-k6BXvw6mxtw.html

  • So many experts in the comment section.

  • Ummm, did this guy use "likelier" instead of "more likely". I'm gonna use that as my password, and by the way. Why wasn't he using grammarly, I bet he was and it just fkd him over..... fkn grammarly

  • so many chair engineers around here xD

  • It's not true that the benchmark of whether fusion is practical is when you have more energy out than it takes to run - it's when you get more money out than it takes to run.

  • Fusion produces also radioactive Waste ... but the alf life time is quite lower

  • In about 100 years we look at this video and go HAHA did we really needed to have such a big fusion reactor to gain such a luttle amount of power? or something like "dad didnt they really have fusion cars?

  • Stars don't work like we think we know they do.

  • With all of the progress, I think we can say that fusion is now ten years away - and always will be.

  • and i live Wright next to ITER so is it saff!!!!

  • My hopes are pinned on the stellerator tocamac. Wendelstein 7-X has been posting some really nice plasma confinement results in the past few years.

  • Disappointed you didn't mention SPARC and the promise that the newer, more powerful superconductors hold.

  • Who said that you need extreme temperatures to reach fusion? What about Brioullin energy and other LENR concepts? There are even ambiant temperatures fusion occurring in ass of chickens :) Concepts presented in the video are so primitive and inefficient. I am considering LENR less fringe than hot reactors and if you want to remain immediately realistic do thorium which have been abandoned because of the military motherfuckers.

  • why nowbody talk's about proton+boron aneutronic laser fusion? No neutrons, no long-term radiactive waste and much smaller devices This is a much more exciting way for fusion. www.nature.com/news/two-laser-boron-fusion-lights-the-way-to-radiation-free-energy-1.13914

  • Why isn‘t there any talk about the stellarator? There is a german research facility making good progress in the field.

  • Thermonuclear bombs are still mostly atomic bombs. They use the second fusion stage to generate neutrons which causes fast fission (i.e. more complete fission that otherwise possible) in a third fission stage. Most of the energy released by a thermonuclear bomb is from fission. The exception is the Tsar Bomba which had it's third uranium stage removed at the last minute. As originally designed it was supposed to be 100 megatons but even the soviets got nervous about that.

  • Lets say for arguments sake, that these experiments, over decades, have cost in the order of some trillions of dollars, minimum. Where would the human race be today if we had spent that money just on solar and wind? We would have a global solar economy, that's what. We hear talk of problems storing energy but if you were a Roan over 1000 years ago, they would not have even thought twice. Solar farms can pump water by day and the water can flow through generators 24-7, simple hydro power. Add to that possibilities with proven geothermal and we already have a range of effective wind turbines, although far too few horizontal micro turbines suitable for homes and businesses. Electricity is critical to a clean future and the solutions need to be foolproof and have longevity few engineers bother planning for these days.

    • If we spend all that money on solar and wind we would have an unstable power grid that relies on overpriced gasoline and coal to throttle the supply and keep it from collapsing. Sure, carbon emissions might be lower overall, but at the same time, they are floored with absolutely no viable alternatives to reduce them to zero, in at least a century to come. With all the money in RnD of nuclear fusion we have a reasonable hope to start switching to 100% green power grid within our lifetimes.

  • you lost me at man made global warming. he's a tip.....nuclear fission power generation is greenhouse gas free and something we can do NOW. don't like it? too bad. it's the best thing to use to get to something better. and you didn't even mention MSR's which is a nuclear reactor you could have in your back yard.

  • We need more nuclear power plants! Just don't build them on the coast or near a fault line.

  • Last Pass is wondeful! Also holy cow i really hoped we were closer to fusion.

  • Dirty secret, iter is already outdated, recent advances in magnetic field generation have rendered the design obsolescent. Keep an eye on a project out of MIT called Spark.

  • Try controlling a FUSION reaction. DUH.

  • I only people werent so unrationally scared of nuclear

  • I think that we are 100+ years away from useful(usable) fusion, maybe even 200+ years. Oh if i could only fast travel in future to see where we would be.

  • Fusion power is just 8 minutes away.

  • Why don't we get Shaggy to offer some of his power.

  • I misread fusion as poison in the title

  • Good job for ignoring the existence of biofuels

  • We're not going to run out of nuclear fission fuels sources for thousands of years... So good one 😉

  • co 2 is good the other pollution not talkt about C02 is air for plants make them grow larger, better, more fruit, more, co2 to h20 conversion, making the ground fertile we add extra co2 to grow house, to get a hie yield this is why we want no Fusion power, we need More Co2 giving plants the time evolve to eat plastics

  • If we had essentially unlimited cheap energy, we would find new ways to use it extravagantly until we drive global warming directly from all the waste heat at end end of all uses of energy. Let's not fall in love with fusion like we did with fission. The Earth must live within its heat budget, and the only way to do that is through renewables which don't create a positive net energy difference in the biosphere.

  • America is actually an excellent energy producer. What is this guy talking about? Moreover, we pollute far less per capita than the majority of developed countries. We’re good..we’re damn good. The question is how can we be even better and lead the world on yet another front?

    • data.worldbank.org/indicator/en.atm.co2e.pc?year_high_desc=true

  • Have you tried turning it off and on again? I hear that duplication glitch is pretty effective.

  • My biggest question is why people are so scared of nuclear fusion? Nuclear Fusion is clearly a great idea.

    • Most importantly, always consider the fact that you need all the information. Sometimes you need information, simply to know you don't have all of it. If you don't think you're wrong, then try throwing out some of your more favorable techniques that relied on sloppy functions when you swap them both out for a new technique entirely. Maybe one combination doesn't pick the lock, but an inverted step will?

    • Can you use all three at once, with partial compensation as a stepping stone for the full process? In other words, use maximum effort. Also, try skipping the next step, and assuming you did it. Usually that breaks things, but it may be more efficient to work around a problem AREA, as opposed to fixing the acute problem.

    • Maybe you could try and get it to suddenly collapse all at once? Probably dangerous, but it would give it a sort of short range momentum kick, right?

  • @scishow how come you do not mention the Stellarator as an alternative to the Tokamak for MCF, especially given the interesting and promising results that came out of the Wendelstein 7-X in 2018?

  • You got a funy nose!

  • 9:48 that was a quick haircut

  • The reason we have not achieved controlled nuclear fusion, is because the research is carried out by nuclear physicists. These are hobbled by an insular communal group-think that stifles any meaningful possibility of achieving a breakthrough. So controlled nuclear fusion? Don't hold your breath.

  • 6:11 that voice crack

  • Nucular, it's spelled nucular

  • What ever happened to Cold Fusion?

  • How about considering Thorium and Molten Salt Reactors? Thorium is everywhere.

  • stop telling wind power is inconsistent. 99% of wind miles is turned off because is to much electricity in grid not because no wind. 30m above ground is constant wind

  • The NIF approach seems like a dead end. How do you capture the produced energy? In practical engineering terms it seems a waste of time and resources

    • You collect energy the same way MCF does. It heats up the chamber walls.

  • So we are still 30yrs away from having it.

  • Safety measures? None, please build supernova and crack this planet in two parts, we had enough

  • Don't worry it's just ten years away. 😅

  • Sci show has some competition in the comment section XP

  • Dumb ass

  • Oh god is this another google reading

  • bye mr green

  • Three lies within 30sec.. that must be a new record!

  • "it's still at least 30 years away. but maybe it won't be for long." that did not make sense to me.

  • Thank you. Because of this video, for the first time, I’m starting to understand all the problems with fusion. I knew it had to be serious issues but I couldn’t understand the inherent problems. Now I’m beginning to understand.

  • God damnit!! Where is Hank? I won't watch these unless it's Hank. He is actually entertaining.

  • Any script which includes the lines "a bunch of energy" as occurs about the the 2:45 mark, suggests the author has no idea what they are talking about. So I stopped watching there. Why is it that the non-regular presenters seem to have dumb-downed scripts? Presumably they have some input on the script.

  • Starts of by saying fusion doesn't produce any radioactive waste or by-product, unlike nuclear fission. Ends up stating correctly, 7 minutes later, that neutrons released from fusion turns the reactor vessel itself highly radioactive. The vessel itself becomes the "radioactive waste". Unlike the fission products and "unburned" mixed oxide fuel elements in nuclear fission reactors, which can be reprocessed to new fuel (in the case of the "unburned" fuel) or diverted for beneficial use e.g. industrial materials and radiomedicine (for the fission products), or even consumed in another type of reactor (heavy isotopes produced in thermal spectrum reactors can be fissioned in fast spectrum reactors), there's pretty much nothing you can do with the radioactive reactor vessel of a fusion reactor. Besides letting it stick around, buried somewhere, irradiating the surroundings for thousands of years.

  • turbulent juice

  • ok i'll be the first to admit, i'm pretty much dumb as dirt, but HOW is solar and wind energy harmful to the ecosystem?

  • The real question is why isn't our grid powered 100 % by fission plants. We have harnessed the power of sun. We should use it.

  • Hi there. Has current theory goes to get a finite amount of fusion energy in this day and age, we expend more energy then we received, as for it's always 30 years away, most physicists theorise you can take that to the bank. It's containing the little amounts that are generated even for a nanosecond.. What's that bloody thing called, the CERN super collider and they want to build a bigger one, they have produced other particles that have lasted longer. Whoop de doo. G . A small God. Goofus. Allegedly.

  • "We don't want radioactive waste hanging out on the planet for thousands of years, threatening peoples lives." Sigh... Nuclear Waste doesn't hurt anyone, and probably never will. It can sit in an underground repository until the end of time. Also the better fission reactors we get, the less time the waste needs to decay to background. A liquid fueled fast reactor will consume all the transuranics leaving only fission products as waste, and those decay relatively quickly. Don't be afraid of long lived waste, Uranium 238 has a 4.4 x 10^9 year half life, but that means it is very very weak at emitting radiation. Short half life = dangerous for short amount of time. Long half life = not dangerous at all for a very long time. Don't be spooked by long half lifes.

  • haha charged gas

  • Would this mean that a fission reactor would be a perpetual motion engine? I thought it was impossible to create energy, we can only change it's type? They said in the video they hope to get more energy out then they put in. Surely if we cannot create energy this isn't possible? Am I being dumb?

    • Thank you, that was a very good explination. +Noah McCann

    • Simmi_ you are correct that you can only get back how much energy was put in. But it doesn’t have to be “you” who put the energy in. This is true with more conventional fuels like oil as well - it is essentially solar energy concentrated over long periods of time. We burn it and get that energy back over short periods of time. Nuclear energy (either fission or fusion) works in a similar way, the energy was put there during the creation of the universe and we are extracting it. The energy necessary to release energy isn’t always the same as the energy being released. Imagine you came upon a 1kg mass balanced atop a tall tower of blocks. That mass has gravitational potential energy. You could release that energy by simply tipping over the tower of blocks. Tipping the blocks likely won’t take as much energy as will be released from the 1kg mass because you don’t have to move the whole tower, you just need to move it enough that it becomes unstable and gravity handles the rest. Now, if you were the one who put the 1kg mass on top of the tower, there would be no net gain of energy (from your perspective), there may even be a net loss if you also had to set up the tower. But if someone else were to set up the tower and 1kg mass, then you would be gaining energy while they would have lost energy.

    • +Noah McCann I did mean mean fusion, I was slightly drunk when writing that comment. I have a basic understanding of general relativity but Im struggling to grasp how putting energy into a machine will net a sustained gain in energy for a long period. Does this not go against the conservation of energy law? I'm meaning you can only ever get back what you put in.

    • Simmi_ I assume you meant “fusion reactor” rather than “fission reactor”- but in either case there is no perpetual motion. As you said, energy must change from one form to another. In the case of nuclear reactions the energy comes from the mass of the input. If you measure the mass of the output, it is less than the input - the difference was converted into energy. This is due to the equivalence of mass and energy, as the (simplified) equation from Einstein shows: e=mc^2, where ‘e’ is energy, ‘m’ is mass, and ‘c’ is the speed of light. You can get a lot of energy from a small amount of mass. But you must first overcome the bonds that hold the nucleus together.

  • Molten salt reactors using thorium are overlooked because is almost ready to go. The money spent on fast breeders should have been changing Thorium232 to Uradium233 instead of changing U radium238 into Plutonium239.

  • Like everything else our all-knowing scientists have done over the last hundred years. Fusion power seems environmentally sound. Until there is a breach of some kind within a *Tokamak. And we end up with a runaway fusion reaction spilling gigantic amount of highly radioactive material into the atmosphere for thirty or a hundred thousand years. Or until some genius just has to prove himself by developing a fusion bomb. And like the Castle Bravo test miscalculates the yield and the Earth ends up being fried and humanity ends up extinct. Another thirty years....*( but yeah, the magnetic field seems like a step forward.) Peace.

    • +Noah McCann Yeah, you're right.

    • Stefan Schleps fusion reactions cannot enter a runaway state largely due to the high temperatures needed to sustain them. While you are likely correct that this technology will have environmental impacts we have not fully considered, I think that is a very poor reason to avoid its study. Particularly given the known environmental impacts of our existing energy production methods. Also, to avoid something because “humanity ends up extinct” is pointless - humanity ends up extinct no matter what we do. Either it actually becomes extinct, or it morphs into something that cannot reasonably be called human in our modern sense. Neither are good reasons to let our technology stagnate.

  • Simple Nuclear Power is a Hoax😂

  • Unless Hank Green is hosting, I don't watch the video.

  • Amateur leftist double talk

  • This video feels like it was made 8 years ago ... there are so many new fusion projects.

  • Fusion does releas radioactive waste but not so mutch and it only stays radioactive for 100 years compared to 100 000

  • Sorry, distracting hand gestures. Couldn't finish.

    • tries to conglomerate all masculinity issues without fixing the cause

  • Once we figure out fusion can’t we just split the atoms and then combine the atoms together again and over and over

    • Josh Wanuck this is not possible, because when the atoms are split some of there mass is converted into energy. It is this energy which is collected by the reactor. One way to think of this is like cutting a chocolate bar - every time you make a cut, a small amount of the chocolate is being lost as small flakes of chocolate or chocolate dust. If you cut the chocolate 10 times and then put the (large) pieces back together, they wouldn’t have the same weight as the original bar. Note that this isn’t a perfect example - because you could collect all of the small chocolate shavings and restore the original weight. In the case of fusion/fission what you’ve converted to energy cannot be easily converted back to mass - and even if it could, that wouldn’t get you any usable energy because the energy you could have used was instead put back into the reactor.

  • we don't have fusion cause scientists are stupid................

  • the new reactor in France just seems like a larger JET remix. The remix to ignition.

  • I wonder whether there is a way that the particle effects from nuclear fission can be harnessed to assist in sustaining a fusion reaction.

  • Man made climate change is a scam.

    • if it all fits like clockwork then why did the guy screw it up in the first place.

  • Slow down! Allow some time for contemplation!

    • triple reverse psychology won't change my mind

  • UGH! Just use Thorium MSRs until then! It's as plentiful as lead and uses 99% of the energy in its bonds, can be bred with radioactive waste to render it inert, and it's walk-away safe and makes no waste of its own. Seriously, why hasn't the science community put all its weight behind this technology before daydreaming about pie-in-the-sky crap that may never pan out? Because it's a stopgap? I just don't get it.

  • What we need is a Thorium Molten Salt Reactor. Thorium is the future.

  • Why Don't We Have Nuclear Fusion Power Yet? Good question, SciShow, but don't ask me. Watch your own video to find out. A better title would have been *'This Is Why We Don't Have Nuclear Fusion Power, Yet'.* You're welcome.

  • Imagine you are a physicist and you pull off a fusion scam once from the government, you are set for the next 30 years.

  • It's 30 years away from no longer 30 years away. Got it.

  • They're gonna set the atmosphere on fire in 2035, just wait lmao

  • #ThoriumEnergy is safer just costly to build, not to maintain however.

  • We could make Thorium reactors but they dont make weapons grade material so the energy dept wont fund it

  • thorium, LIFTR

  • Smh lets go fusion

  • Fission fuel can last tens of thousands of years if we allow refining of the waste and Fast breeder reactors. This is why Canada and Australia oppose Nuclear disarmament despite not having nuclear weapons... because nuclear disarmament would make these technologies banned.

  • You see, it's not a thermal energy. It's electromagnetic.

  • Solar does cause climate change, though, right? Production of panels shoves a bunch of crap into the atmosphere and environment. Additionally, battery production for power storage is terrible for the environment.

  • I wonder if there are any black holes somewhere in space, made by past civilizations with uncontrolled fusion experiments..