Can Nuclear Fusion Reactors Save The World?


Josh: Josh Clark

Chuck: Charles W. "Chuck" Bryant

Vo: Voiceover Speaker

Vo: Welcome to Stuff You Should Know from HowStuffWorks.com

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Josh: Hey, and welcome to the podcast. I'm Josh Clark. There's Charles W. "Chuck" Bryant. And there's Jeri, who's a barrel of laughs. And this is Stuff You Should Know.

Chuck: She gave us the old quick start.

Josh: Yeah.

Chuck: Like, "I don't want to hear it anymore. I'm pressing record." [LAUGHS]

Josh: Yeah, she knows that shuts me up, or at least cuts off whatever conversation I'm chiding her with.

Chuck: It was great. I'm telling you. If we could release the 20 seconds before each show as its own show.

Josh: Yeah?

Chuck: It would be terrible. No one would care.

Josh: No. We'd think it was funny, but everybody else would be like, "You edit this out for a reason."

Chuck: Yep.

Josh: So, Chuck.

Chuck: Mm-hmm.

Josh: How you doing?

Chuck: Great.

Josh: Have you ever been to Aix-en-Provence, France?

Chuck: No. Is that a place?

Josh: Yeah.

Chuck: No, I haven't.

Josh: It is a rustic little town in Provence. And it is strangely, maybe even ironically in the non-hipster use but in the actual-

Chuck: Yeah. It's a real word.

Josh: -definition of the word, also site to one of the most futuristic engineering projects humanity has ever undertaken.

Chuck: "Mee-mur-mee." That's the sound it makes.

Josh: Oh, I thought you were mocking me-

Chuck: [LAUGHS] No, no, no.

Josh: -for being thrilled by the thought of this thing.

Chuck: No, it is kind of funny that this thing is in a sleepy little town.

Josh: Yeah. A hamlet maybe even.

Chuck: It's like CERN in Switzerland, that's not in the city, is it?

Josh: No.

Chuck: You can't build these things in cities. That's why they're in sleepy towns.

Josh: Exactly.

Chuck: Because no one knows they're being poisoned.

Josh: Yeah, and you can push the mayor around pretty easy.

Chuck: [LAUGHS] Exactly.

Josh: This thing is called ITER, I-T-E-R, which is an acronym for the International Thermonuclear Experimental Reactor.

Chuck: That's right.

Josh: Which really gets the point across.

Chuck: Did you know the word acronym is an acronym? That's not true.

Josh: Okay.

Chuck: I just wanted to see how long you would try and sort it out in your head, like what it means. [LAUGHS]

Josh: I would have kept going another 30 seconds maybe.

Chuck: That would have been a great joke. I could have just kept it going like, "I'm not going to tell you."

Josh: I would have-maybe 15 seconds. You would have gotten that much more.

Chuck: Because you would have looked it up? Sure.

Josh: So-I wouldn't have looked it up. I would have figured it out myself. Anyway ITER is this colossal engineering project. Somebody compared it to the pyramids at Giza.

Chuck: Oh, wow.

Josh: Yeah. That's exciting stuff. The thing is it's a nuclear fusion reactor, and it's the culmination of decades of attempts to create a nuclear fusion reactor.

Chuck: Yes.

Josh: Because we've got fission down. And we'll talk about the difference in a minute. But fusion has been very elusive. And nowhere is it more apparent than in the ITER project, because this thing is going to cost approximately $50 billion when it's completed. $50 billion. They started it in 1993. They're hoping to turn on the switch in 2020, but it's looking like 2023 or 2024. And it won't be starting to produce anything until the 2040s at the earliest.

Chuck: So what's the point? [LAUGHS]

Josh: I'll tell you the point. If we can figure out nuclear fusion, Chuck, the world's-literally the world's energy problems will be solved for millennia. If we can just figure this out, we will have a almost no radioactivity nuclear option, almost limitless fuel supply-totally green, clean.

Chuck: Yeah, no pollution, no greenhouse emissions.

Josh: Right. And with plenty of energy to spare.

Chuck: Yeah.

Josh: Using the already extant infrastructure we have to supply power. Like you don't have to completely rebuild everything, you can just-to the electrical cables outside, it'll be the exact same thing.

Chuck: Yeah, you can just go to a nuclear fission reactor and press the button that says "fusion" and it'll all of a sudden join atoms instead of split them.

Josh: Exactly.

Chuck: It's that easy.

Josh: That's what the difference is. With fission you're splitting atoms and you're gaining energy from that. With fusion you're smacking them in together and you're gaining even more energy because you're exploiting a different fundamental force.

Chuck: Yeah, and that-I was being coy. Clearly there is no button, because we would have pushed it a long time ago.

Josh: Yeah.

Chuck: And when I say no pollution and no greenhouse emissions before the pedantic among you write in, we know that just even shipping something from here to there causes pollution and greenhouse emissions.

Josh: Yeah. Good call.

Chuck: But we're talking about the output of the reactor itself is very green.

Josh: So if you want to know all about ITER, well, we're going to talk about it here or there because you just can't talk about nuclear fusion reactors and not mention ITER. But if you want to know a lot about ITER, there is a really great article called "A Star in a Bottle." And it's by a person named Raffi Khatchadourian. And it was written in The New Yorker not too long ago. And, man, it is every detail you want to know about the ITER project written really well. And it's long, but it's totally worth the read.

Chuck: Yeah, it's all over the news lately, and for good reason. You said a lot of energy. I have a stat. Gonna throw back to the old days here. Per kilogram of fuel, if we're talking fusion and fission.

Josh: Lay it on me.

Chuck: Fusion produces four times more energy than fission.

Josh: I saw seven.

Chuck: It's probably one of those things where it's like four to five to ten or something.

Josh: Right.

Chuck: I found four times.

Josh: Okay.

Chuck: And ten million times more than coal.

Josh: Yeah.

Chuck: Ten million times the energy as coal.

Josh: Yeah.

Chuck: And that's with equal fuel, per kilogram of fuel.

Josh: Right.

Chuck: That's just-I mean, it is the future.

Josh: Yeah, and you can say, "Well, that's great because we want 18 million times the amount of power that coal provides." You can say, "Whoa there, buddy. You can also bring it backwards." Because you can supply an awful lot of power then, with a lot less fuel. Like the advantages of nuclear fusion are mind-boggling.

Chuck: Sure. And very few downsides, which we'll get to of course, but.

Josh: Yeah, I mean, like really genuinely; it's not just like some-like, "Here's all the great stuff about it, and just don't pay attention to all these like really horrible aspects."

Chuck: Yeah.

Josh: Like there really aren't too many downsides. The downside is we are at this moment incapable of successfully creating a commercially viable nuclear fusion reactor.

Chuck: That's right.

Josh: But we've got an understanding of what the challenges are ahead of us thanks to the last 50 or so years of really, really, really smart physicists working on the problem of nuclear fusion. And the great inspiration for nuclear fusion is the Sun. The Sun, and all starts like it, are enormous, immense nuclear fusion reactors. So if you are building a nuclear fusion reactor here on Earth, you're essentially creating a star. And that is a very difficult thing to do, it turns out.

Chuck: Yeah, the Sun creates-I know we talked about the Sun in our very famous episode on the Sun. The Sun creates 620 million metric tons-it fuses 620 million metric tons of hydrogen at its core, every second. So every second at the Sun's core it produces enough power to light up New York City for a hundred years.

Josh: New York City?

Chuck: Every second. And that's the Sun. And all we want to do is do the same thing on a much smaller scale.

Josh: That's all.

Chuck: I think the guy-there was this kid who built one in his garage and he said he wanted to-I saw this TED Talk. He wanted to create a star in a box, is what we called it.

Josh: Yeah, I've seen it. Like this New Yorker called it a star in a bottle.

Chuck: Yeah, this kid's name is Taylor Wilson, and he's a nuclear physicist, and he's like 16.

Josh: Wow. He's like Doogie Howser.

Chuck: And he creates-yeah, he created a successful one. And the key, though, is not to be able to create the fusion. The key is to be able to harness enough plasma, which we'll get to, at a high enough temperature and density for there to be a net power gain.

Josh: Right.

Chuck: Like you can create fusion. But in order to get out more than you're putting in is the only thing that matters, because what you want to do is create electricity.

Josh: Exactly. There's two huge challenges right now to nuclear fusion. We pretty much understand it enough to start it going and get energy from it. The problem is material science isn't at a point where it can build a containment vessel to really house a thermonuclear reactor.

Chuck: Yeah.

Josh: And then the other big obstacle is, like you said, net energy gain. Like if you're putting in as much or more energy than you're getting out of your nuclear reactor, then you're wasting energy, and it's the opposite of what you're supposed to be doing.

Chuck: Yeah, they're not just trying to impress people with their science knowledge; they're trying to create energy.

Josh: Up to now, though, Chuck, like every single thermonuclear reactor that's ever been built has just been impressing people with knowledge.

Chuck: Sure.

Josh: Like they haven't gotten any net energy out of a single thermonuclear fusion reactor yet.

Chuck: Oh, see, I have that they have, right now they're up to like 10-presently they're at 10 megawatts.

Josh: Oh, is that right?

Chuck: Yeah.

Josh: And that's more than they put into it?

Chuck: A net gain of 10 megawatts currently.

Josh: Everything I saw was when we turn this thing on it should have a net gain, but I didn't see that they've actually done it.

Chuck: Yeah, 10 megawatts now, and ITER is going to produce 500 megawatts once it's fully operational.

Josh: Right. So the next challenge then is this: if we're already getting a net energy gain out of it, then that means that the net energy gain is-it's not sustainable. Like you said, you want to keep the thing going so you don't have to keep starting from scratch to power it up. You want it to basically be self-sustaining-

Chuck: Yeah, man.

Josh: -so you just have to add a little more fuel to it.

Chuck: That's the dream.

Josh: So let's talk about the history of fusion reactors, Chuck.

Chuck: Yeah, it kind of goes back to this guy named Lyman Spitzer.

Josh: Mm-hmm.

Chuck: He was a 36-year-old Princeton astrophysicist. And this was in the 1950s. And he was recruited to work on the H-bomb, and went out and got a copy of a paper that was released from Germany, I think, right?

Josh: No.

Chuck: That had done previous experiments?

Josh: Argentina.

Chuck: Oh, Argentina?

Josh: Yeah, they announced that they had-

Chuck: Man, how'd I get that wrong?

Josh: They had successfully built a fusion reactor.

Chuck: Right. So he gets this paper, goes on a ski trip, starts thinking about how he can do this, takes a little break from his job building the H-bomb, and figures out, you know, "I think it's possible if we can harness this plasma." I guess we should just go ahead and define what plasma is, since we keep saying it.

Josh: Well, there's the normal three energy states that we're familiar with: water, solid, and gas. Liquid, solid, and gas, right?

Chuck: Right.

Josh: There's a fourth one. It's plasma. And plasma is basically like an energetic gas where the temperatures are so high that whatever atoms you put into it, the electrons are stripped off and allowed to move around freely.

Chuck: Right.

Josh: Basically the surface of the Sun is plasma. That's what plasma is. It's a gas. It's a roiling gas that's really hard to control and is really unpredictable.

Chuck: Which is why we see the Sun-like that rippling wavy looking thing, that's plasma.

Josh: Right. And the reason the Sun manages to stay together is because it is enormously massive and has a ton of gravity at its core.

Chuck: Yeah, we don't have that advantage here on Earth.

Josh: We don't. So we try to make up for that by increasing the temperature.

Chuck: That's right. And he was onto it way back then in the 1950s. "If we can just harness this, if we can just get it hot enough." And he created a tabletop device called the stellarator. And it was in a figure eight position. It was a pipe in a figure eight. And this would keep things from banging into walls theoretically. And he was onto something because-well, we'll get to Lockheed later, but they're using a similar device now, a figure eight.

Josh: Oh yeah?

Chuck: Yeah.

Josh: I didn't realize that was a figure eight.

Chuck: It is. Which is weird because what they eventually found out was that a doughnut shape was really the key to get that net gain.

Josh: And the reason that they found out that a doughnut shape worked was because in, I think, the late '50s, the U.S. had run up against a wall. They were saying like, "Okay. We've got this but we can't control the plasma." Because think about it. What you're trying to do is create a star inside something, but it can't touch any of the vessel that it's in, or else it'll just completely erupt it. Right?

Chuck: Yeah. They compared it to holding jelly in rubber bands.

Josh: Right. It was just like you can't-they couldn't figure out how to control the plasma. So when the U.S. ran up against this wall they said, "Hey, rest of the world, we're going to declassify what Lyman Spitz-" Lyman Spitzer?

Chuck: Yeah.

Josh: "-has been doing."

Chuck: "Help us out."

Josh: "And, like, we'll share if you guys share." And it turns out that the Russians had already come up against this problem and licked it. They figured out that if you put the thing in what's called a toroidal shape, a doughnut shape, using electromagnets, you can tame the plasma essentially. And the doughnut shape itself was pretty ingenious, but the real stroke of genius was by running electromagnets in rings around the doughnut. So it's like you have a doughnut and you put a bunch of earrings around it. Right?

Chuck: Yeah.

Josh: And those are electromagnets. So you're creating an electromagnetic force field which contains the plasma. But then you also put an electromagnetic force field in the middle of the plasma, so not only does it heat it up to the temperatures you want, it also stabilizes it further. So the Russians had invented what they call the tokamak, which is this doughnut-shape nuclear fusion reactor that basically became the standard for the next 50 years or so.

Chuck: Yeah, you basically could achieve a really dense, super hot plasma. And we'll get into temperatures and stuff in a bit. But since we can't create that kind of pressure that they have in the Sun due to their gravity-their gravity-the Sun's gravity. You know, the Sun and all those people.

Josh: Yeah.

Chuck: Like you said, we had to make up for it here on Earth with temperatures.

Josh: Right. Because apparently if you are in the middle of a nuclear reactor, a nuclear fusion reactor, you're going to find that the temperatures inside are about six times hotter than the core of the Sun, not even the surface of the Sun, the core of the Sun. And the reason why it has to be so much hotter is because, like you said, we can't replicate that density. We can get to those temperatures that we need, but we can't get to that density, so we have to make up for it. So we'll talk about kind of the physics of what's going on here and why you have to have high temperatures and what we're making up for with density and everything right after this.

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Josh: So, Chuck, we're talking about nuclear fusion. And it's actually surprisingly understandable, at its most basic core.

Chuck: Yeah. You're fusing atoms. It's not the hardest thing in the world to wrap your head around.

Josh: Yeah, so with fission we're splitting atoms. You're taking an atom and you're splitting its nuclei apart. You're splitting the neutrons and the protons apart from one another. And when you do that, one of the four fundamental forces, electromagnetic force, pushes them away. And you get this burst of energy. With fusion you're taking nuclei from different atoms, you're taking protons and neutrons and you're smashing them together. And when you do that, you're unleashing what's called the strong force, which appropriately enough is stronger than electromagnetic force, which is why nuclear fusion yields more energy than nuclear fission.

Chuck: Yeah, Einstein himself said, you know, each time you smash these things together you're going to lose a little bit of mass. And that little bit of mass is a ton of energy as it turns out.

Josh: Mm-hmm. That's right. The famous E = mc.2

Chuck: Yeah, and I don't think he realized in 1905-or maybe Einstein did.

Josh: Einstein probably did.

Chuck: Yeah, Einstein probably did.

Josh: I would guess he did.

Chuck: Yeah.

Josh: So the problem is even though it is very easy, just smash some protons together, there is a tremendous amount of resistance to that smashing together.

Chuck: They don't want to smash together.

Josh: No, because it's just like if you take a magnet, two magnets, and you put the positive poles towards one another. They repel one another. Right?

Chuck: Yeah.

Josh: Same thing-that's the same principle on an atomic level, too. If you take protons, which are positively charged particles, and try to put them together, they repel one another. And the closer you get them together the stronger the repellant force is, the electromagnetic force. Right?

Chuck: Yeah.

Josh: But, if you can get them close enough, the electromagnetic force is overcome by that strong force, the strong nuclear force, and they become bound together. Because the strong force is that one of those four fundamental forces of the universe, and that is the force that keeps atoms together. And that force is stronger than the force that repels like-charged particles.

Chuck: Yeah. And when you talk about close, they need to be within 1 x 10-15 meters of one another in order to fuse.

Josh: Right, so that is-if you will indulge me.

Chuck: Sure. Are you going to read a bunch of zeros?

Josh: Yeah.

Chuck: [LAUGHS]

Josh: It's 0.000000000000001 meters apart.

Chuck: [LAUGHS] Right.

Josh: That's how close they have to be.

Chuck: That's right, to get them to accept one another and to fuse. I think-I have a theory that if they-they're not fusing because they think they're going to be made into a bomb, and if we told them that we were creating energy, they might be more willing to fuse together.

Josh: Yeah, because protons are peaceniks. Everybody knows that.

Chuck: Sure.

Josh: So when they do fuse together, right, when you do cross that threshold and the strong force takes over and overcomes the electromagnetic force, like we said, a tremendous amount of energy is released. And it's released in part in the form of neutrinos, neutrons, right? Which are neutral particles which suddenly start carrying a tremendous amount of kinetic energy. So let's say you have one atom, and you've got another atom. And they're both like, "I'm not getting close to you. We're not going to get-okay, we got together."

Chuck: Yes.

Josh: That force, that mass that's displaced is transferred through the neutron that gets kicked off of the atom. Right?

Chuck: Yeah.

Josh: And it's carried out. Now, a neutron doesn't have any kind of positive or negative charge. It's neutral. It's a neutron, which means that it can pass through the very electromagnetic fields that are keeping this plasma, where this reaction is taking place, together. Once that happens, Chuck, it can go out to what's called the blanket wall in a thermonuclear reactor, warm it, and then that heat is transferred into a water-cooling system. The water is warmed up, turns to steam, which generates-which, I guess, moves a turbine. And then all of a sudden the turbine is producing electricity.

Chuck: Yeah, it's funny how it just gets so complex, but all you're still trying to do is create steam to turn a turbine.

Josh: Yeah, it's like hooking the ISS up to a horse.

Chuck: Right. [LAUGHS]

Josh: You know? Move it over there.

Chuck: So there are a few types of fusion reactions. The ultimate goal-right now what we can do, on a small scale, is what's called a deuterium-tritium reaction.

Josh: Yeah.

Chuck: That's the one that we can currently achieve. That's one atom of deuterium and one atom of tritium combining to form a helium-4 atom and a neutron. The ultimate goal-I mean, that's good. And that'll create a lot of energy. But there are a few downsides. Tritium is radioactive, for one.

Josh: You have to mine it from lithium.

Chuck: Yeah.

Josh: And lithium is fairly rare.

Chuck: Sure. The ultimate goal is to reach deuterium-deuterium reactions, which is two deuterium atoms combining to form that helium-3 and a neutron. And you can get that from the sea water. It's abundant, almost limitless. And I couldn't find this, but I think clean water can be a residual effect of this. Am I wrong?

Josh: I don't know if it's-well, you're probably not injecting water, but to get the deuterium-

Chuck: Uh-huh.

Josh: I mean, desalination plants are the key to the future as far as supplying the world with fresh water.

Chuck: Yeah, I though I saw somewhere where it was an actual byproduct.

Josh: Is that right?

Chuck: Yeah, but then I couldn't find it, so I'm not sure if that's right or not.

Josh: You know what? You just jogged my memory. I feel like in a hydrogen-powered car water is one of the byproducts.

Chuck: So maybe so.

Josh: Yeah.

Chuck: All right. Don't quote me on that, though. But at the very least it's a great way to create energy.

Josh: Right. And you also can get tritium from helium, I believe. So even now with the deuterium-tritium reactions that we're working on, there's already a workaround. You know? Like you can create a thermonuclear reactor that's a breeding reactor, to where the byproduct, helium, can be used to harvest more of the fuel you're using, tritium.

Chuck: Yeah, and aren't we running low on helium?

Josh: We are. Which is-like remember when we were talking about in the dirigible, the Zeppelin? Which one was it?

Chuck: Well-

Josh: Blimps? "How Blimps Work."

Chuck: Yeah, and then a long time ago we did one on, what was it?

Josh: The MARS turbine.

Chuck: Yeah, MARS turbine requires helium.

Josh: Yeah, but, yes, there is very clearly a helium shortage. And the idea that we're just using it for party balloons rather than this is scary.

Chuck: Yeah, and don't be confused if we say things like deuterium and it sounds super complex. All that is is hydrogen with an extra neutron.

Josh: Yeah, it's an isotope.

Chuck: Yeah.

Josh: So there's three isotopes of hydrogen, and they're all still the same element-they're all still hydrogen-but they have different configurations as far as their neutrons go. So protium is a hydrogen isotope with one proton and no neutrons. Deuterium is a hydrogen isotope with one proton and one neutron. And tritium is a hydrogen isotope with one proton and two neutrons. And like you said, tritium is radioactive, but the beauty of it is you need very, very, very little of it to fuel a nuclear fusion reactor. And it becomes a stable helium, a nonradioactive helium, in the reactor. So you don't have this leftover radioactive fuel. Isn't that awesome?

Chuck: Yeah. I think they said it would be equivalent of the radiation we just see every day in walking around on the street. Right?

Josh: Yes. The background radiation, I believe. I saw that too. The thing is is the parts to the nuclear reactor themselves will become irradiated over time. Apparently though, compared to the kind of radioactivity that's generated from nuclear fission, this stuff you could just disassemble and bury in the desert for 100 years, go back and dig back up, and it'll be totally inactivated. So the stuff that is radioactive is extraordinarily manageable.

Chuck: Yeah, it is. And, like I said, we don't want to make it sound like this is perfect. They do predict the short- to medium-term radioactive waste problem. And they say that's due to activation of the structural materials.

Josh: Right. The actual thermonuclear device itself.

Chuck: Yeah, and while you don't need much tritium, even a few grams of tritium is problematic. But hopefully, you know, there's no accident. Although they say accidents with these-if you just turn the power off, it stops everything. It's not like a chain reaction can occur like a fission reactor, where it's out of your control

Josh: There's not a meltdown. Which, also if you want to know more about that go listen to our "How Nuclear Meltdowns Work" episode. That was pretty good. We released it right after Fukushima.

Chuck: Oh, yeah.

Josh: But it applies to all fission reactors.

Chuck: That's right.

Josh: So the goal is ultimately deuterium-deuterium reactions, where you're pairing those together.

Chuck: That just sounds clean.

Josh: It does. And the reason why is, again, it's abundant fuel. You can get it from desalinating sea water. And then secondly it's not radioactive at any point. So it wouldn't make the thermonuclear reactor itself radioactive, too.

Chuck: That's right.

Josh: The reason why we're not doing that already is because we can't achieve the temperatures necessary.

Chuck: That's right. Which leads us to the two big stumbling blocks. Everyone knows this is a great idea. There's no one out there saying, "Oh, I don't know about this fusion thing."

Josh: Right.

Chuck: "Creating a star in a box sounds kind of weird." The problem is the barriers that we have here on planet Earth, which is, one, temperature and, two, pressure. We have achieved the temperature; the requirement is 100 million Kelvin. And, like you said, that's about six times hotter than the Sun's core. Which is pretty intense. And the other is pressure. Like we said, we need to get them within-I'm not going to make you read all those zeros again, but smash-

Josh: I will.

Chuck: -smash them that close in order to fuse. And since we don't have that kind of mass and gravity that the Sun does, there are a few pretty genius ways that we're working around that.

Josh: Yeah, there's basically two, as it stands. And then the Lockheed Martin one, which a lot of people are skeptical about, we should say. It's kind of a variation on one theme. But basically there's two ways that we've figured out to create nuclear fusion reactors so far. One is using magnetic confinement, and the other is using inertial confinement. So magnetic confinement uses that tokamak technology.

Chuck: Yeah, it's sort of like CERN. You know, it's using magnets to create pressure. I guess in CERN's case they're using it to create speed. But in this case it's to create pressure.

Josh: Right. So what you're doing is you have this doughnut-shaped chamber, and that's your reaction chamber. And then, again, rings around the doughnut that go around the inside and outside of the doughnut.

Chuck: Mmm.

Josh: I know, I'm kind of imagining wonderful doughnuts, too.

Chuck: We're going Homer Simpson here.

Josh: They create electromagnetic fields. Now remember, this plasma is hydrogen gas that's been heated up to a temperature so hot that the electrons just float off and move around freely. And because of this higher temperature, these particles have become really, really energized. So they're moving and bouncing all over the place. And the pressure is building up. But because electrons are negatively charged and because protons are positively charged, if you use alternating electromagnetic fields, you can contain this plasma so that this incredibly hot gas that's six times hotter than the core of the Sun can be contained within the electromagnetic fields.

Chuck: That's right. And we talked about "power in, power out." You'd need about 70 megawatts of power to create this, to start this fusion reaction. But you're going to yield about 500 megawatts.

Josh: That's the ITER project, I believe.

Chuck: Yeah, that's the ITER. And that's only a 300- to 500-second reaction. But like we said earlier, the eventual goal is that it's sustaining itself, which is just a beautiful concept.

Josh: Yeah. So basically what they do is the gas is injected into the chamber, the hydrogen gas, and then there's the electromagnetic fields that are holding the plasma in place. But then, remember, we said the Russians figured out that if you put an electromagnetic field in the middle of the whole thing, it will stabilize that plasma but it also heats it up. So it serves this double purpose. And then just to add a little extra temperature, they shoot it with microwaves and some other stuff and then heat it up, and then as the plasma goes crazy and all the fusion energy is released, the neutrons move their way outside of the electromagnetic field into the blanket, which they heat up. And the heat energy is transferred to power that turbine or move the horse down the lane.

Chuck: And it's just creating steam.

Josh: Yeah, and, I mean, that's what ITER is doing right now. That's what they're trying to prove. And then also, as ITER is spending billions and billions and billions of dollars and running into tons of delays-and it's an amazing project-Lockheed Martin basically just came out and said, "Oh, by the way, this thing that you're trying to do that's going to be 100 feet tall and require staggering amounts of energy and money, we're doing one that puts out the same amount of energy as yours but it's a tenth of the size," which means it's almost out of the gate commercially viable.

Chuck: Yeah, that is their Skunk Works division of Lockheed. And they announced this like three days ago, here in mid October. And they've gotten a lot of blowback from the scientific community.

Josh: Because they wouldn't release data.

Chuck: They don't have data. They said it's a high beta device right now, and kind of shut out the scientific community as far as questions go. And every scientist that I saw interviewed for this said, "Yeah, they're trying to get some attention to get some partners to join in."

Josh: Well, yeah, plus it makes you want to run out and buy Lockheed Martin stock.

Chuck: Yeah, exactly. [LAUGHS]

Josh: Because if one company can figure out how to create a thermonuclear fusion reactor here on Earth that's scalable-

Chuck: That fits in a truck.

Josh: Yeah, then that person would be very wealthy.

Chuck: Yeah, so it's a dubious claim, but they are, you know-they're working toward a good thing. I'm not like pooh-poohing the whole thing.

Josh: Right.

Chuck: But until they have hard data and like some proof, then I think the scientific community has got their arms folded right now.

Josh: Yeah, and I mean they have released some details. It's just not detailed enough for a scientist. It's detailed enough for Aviation Week.

Chuck: I bought it.

Josh: Yeah. They wrote an article on it. And basically what the guy they interviewed was saying was that over at ITER they have a low beta ratio, which is the amount of electromagnetism that you need compared to the amount of plasma you can put into the chamber. So there's like 5% plasma to 95% electromagnetism just to keep this plasma thing from just blowing up. Because that can happen.

Chuck: Sure.

Josh: It might not melt down, but if everything went wrong, the whole thing could blow up.

Chuck: Well, and, you know, you know what an atomic bomb is? It's a fusion reaction.

Josh: Right. This is a lot of those all put together in one 100-foot tower. This guy was saying that the beta ratio for their machine is like 100%. So what he was saying is they figured out a way, and again, it's not very detailed, but they figured out a way to contain the plasma but in a way that also allows it to expand. Because if you think about it, the more plasma there is, the more hydrogen atoms there are; the more hydrogen atoms, the more isotopes there are; the more nuclear fusion reactions or events you can have, the more energy you can yield. Right?

Chuck: Yeah.

Josh: So they're saying they figured out how to contain the plasma. But, again, like you said, the scientific community is really skeptical because they think it's just a PR stunt.

Chuck: Well, I think they made the mistake by saying they invented a magicometer to make it all happen, and don't ask about it.

Josh: Yeah, right.

Chuck: I did see, though, where Lockheed was using the figure eight, the stellarator configuration.

Josh: Yeah.

Chuck: And I think that's true. I found a couple more sources that were kind of vague about it, and I think the details on it are just vague, period, but I don't know why they would abandon the doughnut shape if the figure eight was, you know, 1950s technology that's sort of been disproven.

Josh: Well, supposedly their whole jam was that even in the doughnut, even in the tokamak, this doughnut-shaped reactor, plasma has a tendency to just move around and make its way out. Like it's still not fully contained. And they're using something, basically mirrors to catch the plasma that's getting out, and moving it to parts of the electromagnetic field that are less dense. So if there's a bunch of protons in this part of the field, that field is being strained, but then maybe there's not that many protons over here. So they use mirrors to direct the protons to the low-density area of the-

Chuck: Just keep it all even?

Josh: -of the field. Yeah. To even the whole thing out.

Chuck: That makes sense.

Josh: Which makes sense. But, again, if you're not releasing data, don't expect the scientific community to buy it.

Chuck: You've got that right.

Josh: So there's another way to build a thermonuclear reactor that's currently being worked on, too, and we'll talk about that right after this.

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Chuck: So, buddy, magnetic confinement is pretty neat. And we talked about that and that's understandable, and I love it. I want to date it. But internal confinement I want to marry, because it has lasers.

Josh: Uh-huh.

Chuck: At the National Ignition Facility at Lawrence Livermore Laboratory they are actually using laser beams. They have a device called the NIF device where they focus 192 laser beams on a single point in a 10-meter diameter target chamber called a hohlraum. That's got to be German. And basically inside that target chamber they have a little tiny pea-sized pellet of deuterium-tritium in a little plastic cylinder. It's funny that it can be plastic somehow. [LAUGHS]

Josh: Yeah, you'd think it would introduce like impurities or something into it.

Chuck: Yeah, or it would need to be like iron or something. I don't know.

Josh: Mm-hmm.

Chuck: It just seems unstable. But that is 1.8 million joules of power from these lasers. And it's going to heat the cylinder up, generate some X-rays, and then that radiation will convert that pellet into plasma and compress it. So, again, they're creating plasma, but instead of smashing it together with magnets, they're super-heating it with lasers.

Josh: So that's your-your money is on that one? You like that one more?

Chuck: I just think it's neat because I like lasers.

Josh: But that's your preference of the two?

Chuck: Yes. Well, actually whichever one works is going to be my preference. [LAUGHS]

Josh: Okay.

Chuck: And that one will yield 50 to 100 times more energy out than energy put in.

Josh: I got you.

Chuck: So that's a good goal.

Josh: So, yeah, I guess basically the whole point of magnetic confinement is that if you can do without electromagnets you have a more simple and elegant solution.

Chuck: Oh, you meant he internal confinement, or-

Josh: Inertial.

Chuck: Inertial.

Josh: Yeah, that's what I mean. Inertial confinement. Basically the whole thing just happens so fast, you don't even need these magnets to confine plasma because you're not creating the sustained ignition, right?

Chuck: Yeah, I might have said internal confinement before, by the way.

Josh: It's inertial.

Chuck: Yeah, I know.

Josh: That's all right.

Chuck: So what about cold fusion, buddy? That was all the rage I remember, back in the '80s.

Josh: Yeah, because in 1989 some researcher said that they successfully created nuclear fusion using just room temperature stuff, like palladium. They took palladium and-

Chuck: Banana peels and beer cans?

Josh: Pretty much. Heavy water, which had deuterium in it. And they put the whole thing together and created nuclear fusion without the high temperatures, hence the name cold fusion. And if you can get around these high temperatures then you work out the whole material science problem. Right? And if you work out the whole material science problem then it's a desirable thing to have cold fusion. The problem is a lot of scientists tried to replicate these guys' findings and weren't able to. So basically they were kicked to the curb.

Chuck: So does that mean has cold fusion been abandoned? Or are people still trying to get on that train?

Josh: No, in 2005 some UCLA researchers basically said, "We think we might have this thing down." And they did. It's something called pyroelectric crystal fusion.

Chuck: Oh, that's right.

Josh: Pyroelectric fusion.

Chuck: They use a crystal?

Josh: Yeah, or basically it's the same result. They do what would be called cold fusion. The problem is is it has a negative net energy yield. You have to put in a lot more energy than you get out of it.

Chuck: Right. Well, that's no good.

Josh: No.

Chuck: ITER seems like they are making headway more than Lockheed, despite their claim. They are being-like we said, it's in Europe, and it's being financed by a bunch of different countries. The U.S. is in, but they're kicking in, I think, the least amount, only about 17 million euros last year. Of course we contributed dollars, but they're giving it to us in euros.

Josh: Right.

Chuck: I think the E.U. spends the most, about 80 million. South Korea and China kicked in about 20 and 19 million respectively each. And I saw earlier where Russia was involved, but then I didn't see what they had contributed financially, so I'm not sure.

Josh: Yeah, they're definitely involved, still.

Chuck: Are they, still?

Josh: Mm-hmm.

Chuck: All right. Well, maybe they're just-we're writing a chit for them for later. They'll just pay us back.

Josh: Right.

Chuck: But it is a very expensive prospect. And you need, you know, countries getting together for something like this. It's not the kind of thing that like the U.S. can take on on their own. I guess unless you're Lockheed Martin.

Josh: Right.

Chuck: And you don't have to prove your data.

Josh: Right. So that's nuclear fusion. We'll see what happens.

Chuck: Yeah, you got anything else?

Josh: Man, no. I just say everybody should go read "A Star in a Bottle" in The New Yorker. It's really, really good.

Chuck: Yeah, it's pretty neat. You can also go to Instructables if you want to build a nuclear fusion reactor in your garage. You can do so. You're not going to create energy because, like we said, you're going to be putting in more than you get out, but there are instructions, and that kid did it. His is a little more advanced than the Instructables one, obviously. But, yeah. I might.

Josh: The 16-year-old kid.

Chuck: Yeah, he's amazing because his was legit. He's done more than that, too. His TED Talk was pretty impressive.

Josh: Cool.

Chuck: He's like working with Homeland Security already for various projects.

Josh: Oh, I'm sure.

Chuck: That have nothing to do with this.

Josh: Yeah, I'm sure.

Chuck: Yeah.

Josh: Well, if you want to learn more about nuclear fusion, you can type those words in the search bar at HowStuffWorks.com. And since I said that it's time for listener mail.

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Josh: And, Chuck, before we do listener mail I want to give a shout-out to our Kiva team.

Chuck: Yeah. For those of you who don't know, we did a podcast many years back on mocro-lending. And Kiva, K-I-VA, dot org is a organization where you can loan entrepreneurs and-well, it used to be just developing counties. Now you can do it here in North America, as well-$20 at a time that you can get paid back for. You can get your money back if you're not happy. Or you can just keep reloaning that money, and it helps them get their small business going. And we started a Kiva team many years ago. And it is killing it. So you've got some stats for us?

Josh: So basically as of October 19th we have loaned-our team has loaned $2.7 million-

Chuck: [WHISTLES]

Josh: -to people in developing counties.

Chuck: Nice.

Josh: And in the U.S. here or there. And the big one is we've exceeded 100,000 loans by our team. Our team only has 8,079 members, so to all 8,079 of you guys, thank you. Way to go. Congratulations.

Chuck: Yes. And thanks, as always, to Glen and Sonia, our de facto Kiva-what would you call them? Presidents?

Josh: Presidents.

Chuck: Presidents of the Stuff You Should Know team?

Josh: Yep.

Chuck: Captains of the Stuff You Should Know team?

Josh: No, presidents.

Chuck: Okay. Presidents.

Josh: Presidentes.

Chuck: Glen is like, "Yes, president."

Josh: Yeah, they've been really, like, keeping it going for us.

Chuck: Yeah, and, you know, sometimes we'll forget, and Glen will nudge us: "Hey, guys, remember the Kiva team. We should mention it."

Josh: Right.

Chuck: And we do so.

Josh: So the next goal we have is for $3 million in loans. And we're on our way to it. So come join us. We don't begrudge people who are late to the party. Just go to Kiva.org/team/StuffYouShouldKnow and you can sign up.

Chuck: That's right.

Josh: So now it's time for listener mail, right?

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Chuck: Indeed, sir. I'm going to call this "Skywriting Follow-up from Australia." "Hey, guys. Recently listened to 'How Skywriting Works' and it reminded me of something. Although this may not be suitable for listener mail," which I disagree actually, because I'm reading it.

Josh: Clearly.

Chuck: "I was maybe eight or nine when a few friends and I were out on the street playing and doing things that nine-year-olds would do." That's so awkward to say that.

Josh: So you're not replacing something right there?

Chuck: No.

Josh: Oh.

Chuck: They were just doing nine-year-old things.

Josh: Okay.

Chuck: It was good clean fun. "We looked up and saw a plane starting to skywrite and were instantly intrigued at what was being written. It started with an H and then an O. This went on for maybe 20 minutes until finally the word 'Hooters' was scrawled across the sky, albeit backwards." So I guess they had the Hooters restaurant chicken wing chain in Australia.

Josh: I guess, or a rich kid.

Chuck: Yeah?

Josh: A really immature rich kid.

Chuck: Yeah, or that. "My brain couldn't comprehend how this person managed to screw up writing a word backwards. The best reason my childish brain could come up with was the skywriting took place somewhere between us and a group of people that it was initially intended for and that I just thought it was written up and downwards rather than across the sky. Until now I never understood or bothered to learn why it was like that. So thank you for keeping the podcast great and allowing me to figure that out." That is from Marlan-oh, boy-Hapuarachchi.

Josh: Nice.

Chuck: Have you ever seen a word like that?

Josh: Hapuarachchi.

Chuck: Hapuarachchi, Marlan from Sydney, Australia. Man.

Josh: Thanks a lot, Marlan H.

Chuck: And that's Marlan with an A, even.

Josh: Oh, yeah?

Chuck: Marlan.

Josh: Huh. Well, thanks a lot, Marlan. And we're going to say it like that.

Chuck: Sure.

Josh: If you have an awesome last name and want to share it with us, you can tweet to us @SYSKPodcast, you can join us on Facebook.com/StuffYouShouldKnow, you can send us an email to StuffPodcast@HowStuffWorks.com, and, as always, join us at our home on the web, StuffYouShouldKnow.com.

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Vo: For more on this and thousands of other topics, visit HowStuffWorks.com.

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