Why Don't We Have Nuclear Fusion Power Yet?

13 806
Nathan Frey
Nathan Frey - 2 hours ago
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?
Rob Karmic
Rob Karmic - 7 hours ago
Have you tried turning it off and on again? I hear that duplication glitch is pretty effective.
Rob Karmic
Rob Karmic - 10 hours ago
My biggest question is why people are so scared of nuclear fusion?
Nuclear Fusion is clearly a great idea.
Rob Karmic
Rob Karmic - 7 hours ago
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?
Rob Karmic
Rob Karmic - 7 hours ago
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.
Rob Karmic
Rob Karmic - 7 hours ago
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?
TeoTull - 11 hours ago
@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?
TIBOR Purzsas
TIBOR Purzsas - 14 hours ago
You got a funy nose!
Shade - 14 hours ago
9:48 that was a quick haircut
Stephen Goodfellow
Stephen Goodfellow - 16 hours ago
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.
Emily Rowland-Rawson
Emily Rowland-Rawson - 16 hours ago
6:11 that voice crack
Xurre - 22 hours ago
Nucular, it's spelled nucular
Conservative Minuteman
What ever happened to Cold Fusion?
hardware4200 - Day ago
How about considering Thorium and Molten Salt Reactors? Thorium is everywhere.
trik - Day ago
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
JK 06667
JK 06667 - Day ago
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
Andy Davies
Andy Davies - 13 hours ago
You collect energy the same way MCF does. It heats up the chamber walls.
Drizzt - Day ago
So we are still 30yrs away from having it.
dinoxtra - Day ago
Safety measures? None, please build supernova and crack this planet in two parts, we had enough
GANTZ100pts - 2 days ago
Don't worry it's just ten years away. 😅
Manny Nanez
Manny Nanez - 2 days ago
Sci show has some competition in the comment section XP
TheOv3rlordK1ng - 2 days ago
Dumb ass
TheOv3rlordK1ng - 2 days ago
Oh god is this another google reading
Gabriel M.
Gabriel M. - 2 days ago
bye mr green
Bjørnar Iversen
Bjørnar Iversen - 2 days ago
Three lies within 30sec.. that must be a new record!
rosselur - 2 days ago
"it's still at least 30 years away. but maybe it won't be for long." that did not make sense to me.
Henry Woodward
Henry Woodward - 2 days ago
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.
Nic Hunter
Nic Hunter - 2 days ago
God damnit!! Where is Hank? I won't watch these unless it's Hank. He is actually entertaining.
TheRumpus - 2 days ago
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.
JS Wong
JS Wong - 2 days ago
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.
Chris Ashby
Chris Ashby - 2 days ago
turbulent juice
C.C. Rider
C.C. Rider - 3 days ago
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?
Sean Haggard
Sean Haggard - 3 days ago
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.
Trevor Johnson
Trevor Johnson - 3 days ago
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.
Charlie Lund
Charlie Lund - 3 days ago
"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.
Snoov747 - 3 days ago
haha charged gas
Simmi_ - 3 days ago
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?
Simmi_ - 2 days ago
Thank you, that was a very good explination. +Noah McCann
Noah McCann
Noah McCann - 2 days ago
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.
Simmi_ - 2 days ago
+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.
Noah McCann
Noah McCann - 3 days ago
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.
William Johnson
William Johnson - 3 days ago
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.
Stefan Schleps
Stefan Schleps - 3 days ago
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.)
Stefan Schleps
Stefan Schleps - 2 days ago
+Noah McCann Yeah, you're right.
Noah McCann
Noah McCann - 3 days ago
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.
WOLTROX - 3 days ago
Simple Nuclear Power is a Hoax😂
Jack - 3 days ago
Unless Hank Green is hosting, I don't watch the video.
Wei Zhao
Wei Zhao - 2 days ago
I want what I want
Dennis Gillanders
Dennis Gillanders - 3 days ago
Amateur leftist double talk
Wei Zhao
Wei Zhao - 2 days ago
pish posh
SciFi Factory
SciFi Factory - 3 days ago
This video feels like it was made 8 years ago ... there are so many new fusion projects.
Per Norrström
Per Norrström - 4 days ago
Fusion does releas radioactive waste but not so mutch and it only stays radioactive for 100 years compared to 100 000
Blue Steel
Blue Steel - 4 days ago
Sorry, distracting hand gestures. Couldn't finish.
Wei Zhao
Wei Zhao - 2 days ago
tries to conglomerate all masculinity issues without fixing the cause
Josh Wanuck
Josh Wanuck - 4 days ago
Once we figure out fusion can’t we just split the atoms and then combine the atoms together again and over and over
Noah McCann
Noah McCann - 3 days ago
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.
Joe Eoj
Joe Eoj - 4 days ago
we don't have fusion cause scientists are stupid................
tyler a
tyler a - 4 days ago
the new reactor in France just seems like a larger JET remix.

The remix to ignition.
JesseMoshe - 4 days ago
I wonder whether there is a way that the particle effects from nuclear fission can be harnessed to assist in sustaining a fusion reaction.
Phone User
Phone User - 4 days ago
Man made climate change is a scam.
Wei Zhao
Wei Zhao - 2 days ago
if it all fits like clockwork then why did the guy screw it up in the first place.
nhzxboi - 4 days ago
Slow down! Allow some time for contemplation!
Wei Zhao
Wei Zhao - 2 days ago
triple reverse psychology won't change my mind
Axel Kusanagi
Axel Kusanagi - 4 days ago
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.
Doom And Gloom
Doom And Gloom - 4 days ago
What we need is a Thorium Molten Salt Reactor.
Thorium is the future.
Fun Trump-fact
Fun Trump-fact - 4 days ago
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.
Hand Solo
Hand Solo - 4 days ago
Imagine you are a physicist and you pull off a fusion scam once from the government, you are set for the next 30 years.
Hand Solo
Hand Solo - 4 days ago
It's 30 years away from no longer 30 years away. Got it.
Silver Wyvern
Silver Wyvern - 5 days ago
They're gonna set the atmosphere on fire in 2035, just wait lmao
Silver Wyvern
Silver Wyvern - 5 days ago
#ThoriumEnergy is safer just costly to build, not to maintain however.
Silver Wyvern
Silver Wyvern - 5 days ago
We could make Thorium reactors but they dont make weapons grade material so the energy dept wont fund it
David Hansen
David Hansen - 5 days ago
thorium, LIFTR
Walter St
Walter St - 5 days ago
Smh lets go fusion
Joel Reid
Joel Reid - 5 days ago
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.
Blue Jay
Blue Jay - 5 days ago
You see, it's not a thermal energy. It's electromagnetic.
SbotTV - 5 days ago
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.
juice8225 - 5 days ago
I wonder if there are any black holes somewhere in space, made by past civilizations with uncontrolled fusion experiments..
kens97sto171 - 5 days ago
One thing that always annoys me about these types of videos. Anytime they portray internal combustion or any use of fossil fuels. They show up car with smokey exhaust spewing out of the tailpipe. When is the last time you saw a modern car doing that? Not since the 1990s and fuel injection became commonplace.
talking about fossil fuels has a finite source of energy that will run out is kind of it misleading also. Best guess is we've got at least a 100 years of fossil fuel if consumption stays consistent. possibly more because there are large fields in Lubbock Texas that have yet to be touched. Plus all of the offshore and deep water oil sources that are expensive but also a possibility.
We should absolutely be working on cleaner Greener energy everybody wants to breathe clean air. But we should do things that make sense in the meantime rather than falling for pie-in-the-sky ideas that can't really generate enough energy efficiently enough or in a cost-effective way.
Skitches - 6 days ago
No mention of the amount of co2 and environment destroyed in the process of making, installing, and maintaining solar and wind power?
Brian Reiner
Brian Reiner - 6 days ago
Doesn't the green new deal want to eliminate nuclear power plants?
Mike Mauck
Mike Mauck - 6 days ago
Do you know the word endothermic? Yes, one fusion releases about 12x more energy than it takes to form the reaction, but it takes tens of millions of tries to get one reaction, thus the overall process is doomed to be endothermic.
SM96 - 6 days ago
yeah no, passwords shouldn't be stored on a remote service's storage even if it's encrypted.
Samuel Westknee
Samuel Westknee - 6 days ago
previously I tought: from +10 years and ITER is done, then project build first commercial = 30 years, but now there is a DEMO in middle ? so 30 + anoter 10-20 ?
briansgenius - 6 days ago
Nice instant haircut :P
Warren - 6 days ago
What if we used thorium in nuclear fission for now? As it’s so much more efficient and effective not to mention more safe than uranium
Ziess1 - 6 days ago
As for fission, it is currently the safest mode of energy production by far. Any wastes that are produced are not only handled properly and quarantined from the rest of the environment, but that said wastes can be also reused due to recent technological developments, actually up to 80% is reusable, thereby shrinking a 3000 year period of radioactivity down to about 600. Nuclear wastes are also the only kinds of waste that get less hazardous as time progresses, unlike, say mercury which is spewed like mad from coal reactors.
LordOfNihil - 6 days ago
videos like this it usually goes:
several minute greeny preach speech about why we need fusion (most normal people get bored here and move along)
several minute primer on the theory of operation (nerds usually get bored here and move along)
talk about one of many high budget big fusion projects (the ones that fuse cash into broken dreams)
end of video
i want to see more polywell love in fusion videos.
i want those infinite range naval vessels bristling with railguns ive been promised.
CG Account
CG Account - 6 days ago
Solar power will also be everywhere soon too lol. Next year. Right when the flying cars and moonbases appear.
David barnes stuff 2
David barnes stuff 2 - 6 days ago
We're trying to make an automatic banana peeler that's powered by a combustion engine. Sure it can be done, but why would you want to do that when there are simpler ways?
sence11 - 7 days ago
"It barely releases any CO2"...
Sorry, why is NUCLEAR fusion producing ANY CO2 at all?
Daniel Foster
Daniel Foster - 7 days ago
There's a lot missing here. You're talking about magnetic confinement, but don't mention the stellarator. Also no mention of Tri-alpha energy (colliding beams, california), general fusion's magnetized target fusion (BC), or the spinoff fusion startup from MIT.
Dragrath1 - 7 days ago
One issue with the whole thing both with Fusion and Fission is the idea of waste The dutch have a saying that there is no such thing as waste only misappropriated resources and this will have to be part of our solution given that the Earth is practically a closed system with finite resources. Ultimately Fission will likely be needed as a stop gap and whether or not we can ever achieve net gain fusion reducing "waste" will have to be a part of the solution.
Lord Samich
Lord Samich - 7 days ago
I hold you personally responsible!
undo.kat - 7 days ago
I can confine plasma in my microwave, I've seen it on youtube
Rom - 7 days ago
Fusion is just a cheap trick to make weak energy sources stronger
macsnafu - 7 days ago
This is SciShow, not EconShow, but a big part of the energy problem is the government intervention into the energy industry. If we allow the market to work with less interference, the trade-offs between the different energy sources would be more apparent and reflected in the prices consumers would have to pay. Running out of fossil fuels? We would know when the market price of fossil fuels started increasing, which would a) encourage people to use less fossil fuels, b) encourage people to use more alternative, non-fossil fuels, and c) stimulate more energy research, which would help to lead to the breakthrough that fusion (or perhaps even some other energy alternative) needs to become a reality.
Zantor Zenodex
Zantor Zenodex - 7 days ago
If a previous presidential administration over 40 years ago hadn't signed a treaty banning the US from reprocessing uranium waste, we would be reprocessing our own fuel and our supply would last much longer (decades) without producing near as much waste. Nuclear fuel reprocessing for fission is the best way to mitigate dangerous radioactive waste.
Tokamaks are incredibly outdated and not considered to be a viable method of producing fusion energy. There are other reactor designs that show far more promise which are worth covering for the MCF method, such as the polywell. The polywell is one design that doesn't depend exclusively on hydrogen isotopes for producing viable quantities of energy.
CowboyCree63 - 7 days ago
Maybe you guys should look past the old technology of nuclear fission, and start looking at technologies like Molten Salt Reactors, and one of the most abundant elements on earth, Thorium, that can be used in the MSR, along with all that radioactive waste you talked about.
James Wayne
James Wayne - 7 days ago
It's always 20 years away.
Shannae Darkehart
Shannae Darkehart - 7 days ago
I don't often downvote on a SciShow video, but this really needed a lot more research to be done before the script was written.
Jedadiah Tucker
Jedadiah Tucker - 7 days ago
i saw a doc on 2nd and 3rd generation fission reactors that can use the waste products of the reactors we currently use. the one guy they kept talking to said the reason we havent built them is the public opinion of anything nuclear is poor so no one wants to pay for it. that seams like a really stupid reason to leave a bunch of toxic stuff laying around when we could be using some portion of it up to make more energy.
Mora Fermi
Mora Fermi - 7 days ago
No mention of MIT's ARC? That's a bummer...
Peter Chan
Peter Chan - 7 days ago
Nuclear power 'clean' . . . provided ONLY that nothing ever goes astray.
Fukushima, anybody?
And Chernobyl, even if almost everybody has completely forgotten about the catastrophe 32 years ago, the vicinity is yet uninhabitable most likely for some tens of thousands of years to come.
The people who had been living near Chernobyl - and their offspring - sure know much more painfully than any scientist by far.
Daniel Dulu
Daniel Dulu - 7 days ago
I read about fusion back in the 70's and it was supposed to be attached to our houses producing what we need. I am not a physicist but when I figured out what was needed and the actual process I very quickly realized the issue is scale. The sun works because it is huge. It's very size controls and contains fusion. The fact that we have to use proportionally more energy than it produces just to keep it in check should be a sign that this is not going to work, EVER.
Tha Hatter
Tha Hatter - 7 days ago
How y'all gonna know how something is gonna work that y'all ain't ever made yet? Seems more like a hypothesis and don't get me wrong y'all probably right about it would work but those statements should be stated as hypothesis and nothing more then that until proven don't you think?
Jwad - 7 days ago
Iter is a stall tactic to do nothing. The brilliant engineers are quickly hired away. Piss on the people. Starve them out.
Dávid Kertész
Dávid Kertész - 7 days ago
I guess they should say it's at least 30 years away.
Connor Stinnett
Connor Stinnett - 7 days ago
After reading up on the German made: "Wendelstein 7-X" stellarotor...
How could you guys at scishow *not* mention -let alone make a video about it?
I mean, the bounds of engineering are getting redefined; with strides I thought never would be reached anytime soon!
Dávid Kertész
Dávid Kertész - 7 days ago
Now I'm imagining a huge internal combustion engine, which burns hidrogen bombs in each cycle.
Eric Delaune
Eric Delaune - 8 days ago
I'm starting to think Thorium is the future, not Hydrogen Fusion.
Daniel Bickford
Daniel Bickford - 8 days ago
Tldr, it's complicated
Tristan Band
Tristan Band - 8 days ago
Honestly, at some point we might have to admit that sustainable fusion reactions MIGHT be only possible with large masses and gravity? My pessimism may very well be unfounded, but it's not a possibility that can be dismissed. It doesn't mean years of research has been fruitless; we learned a lot about physics in the process that we might not have otherwise learned, and new knowledge always justifies investment. But it does mean that, in trying to achieve fusion as a source of electricity, we could be chasing the impossible.
Fission has a place, but not long term. Like it or not, we may end up relying on solar panels and wind turbines combined with batteries for power long term.
Matthew Hammond
Matthew Hammond - 8 days ago
Wind and solar are “inconsistent?”
He does not mention that coal power plants are required to make up for the difference in power or the added expense.
Koppa Dasao
Koppa Dasao - 8 days ago
Well, build nuclear fission plants, if you think about the environment!
rosario lake
rosario lake - 8 days ago
the answer is zero gravity to stabilize all of it
PrivateSi - 8 days ago
You need the gravity of a star to contain the reaction. You'll always use more electricity than you get out using artificial magnetic fields... Fact, proven time and time again by 10 of 1000s of fusion experiments.
Next videos