David Kirtley: Nuclear Fusion, Plasma Physics, and the Future of Energy | Lex Fridman Podcast #485

0:00 The following is a conversation with David Kirtley, a nuclear engineer,

0:04 expert on nuclear fusion, and the CEO of Helion Energy,

0:08 a company working on building nuclear fusion reactors and have made incredible

0:13 progress in a short period of time that make it seem possible,

0:17 like we could actually get there as a civilization.

0:21 This is exciting because nuclear fusion, if achieved commercially,

0:24 will solve most of our energy needs in a clean,

0:28 safe way, providing virtually unlimited clean electricity.

0:31 The problem is that fusion is incredibly difficult to achieve.

0:35 You need to heat hydrogen to over 100 million degrees

0:39 Celsius and contain it long enough for atoms to fuse.

0:43 That's why the joke in the past has been

0:46 that fusion is 30 years away and always will be.

0:49 Just in case you're not familiar,

0:52 let me clarify the difference between nuclear fusion and nuclear fission.

0:57 By the way, I believe according to the excellent subreddit post by pmgoodbeer

1:04 on this, the preferred pronunciation of the latter

1:08 in the US is nuclear fission, like vision.

1:11 And in the UK and other countries is nuclear fission, like mission.

1:18 I prefer the nuclear fission pronunciation because America.

1:24 So today's nuclear power plants use nuclear fission.

1:29 They split apart heavy uranium atoms to release energy.

1:33 Fusion does the opposite.

1:35 It combines light hydrogen atoms together,

1:37 the same reaction that powers the Sun and the stars.

1:41 The result is that it's clean fuel from water, no long-lived radioactive waste,

1:47 inherently safe because a fusion reactor can't melt down.

1:50 If something goes wrong, the reactor simply stops.

1:54 And there's no carbon emissions.

1:56 On a more technical side,

1:58 Helion uses a different approach to fusion than has traditionally been done.

2:03 Most fusion efforts have used tokamaks,

2:06 which are these giant donut-shaped magnetic containment chambers.

2:09 Helion uses pulsed magnetoinertial fusion.

2:12 David gets into the super technical

2:16 physics and engineering details in this episode, which was fun and fascinating.

2:21 I think it's important to remember that for all of human history,

2:26 we've been limited by energy scarcity.

2:28 And every major leap in civilization, agriculture, industrialization,

2:33 information age, came in part from unlocking new energy sources.

2:37 If someone is able to solve commercial fusion,

2:41 we would enter a new era of energy

2:44 abundance that fundamentally changes what's possible for us humans.

2:49 I'm excited for the future,

2:53 and I'm excited for super technical physics podcast episodes.

2:59 This is a Lex Fridman podcast.

3:01 To support it, please check out our sponsors in the description

3:03 where you can also find links to contact me,

3:06 ask questions, give feedback, and so on.

3:09 And now, dear friends, here's David Kirtley.

3:13 Let's start with the big picture.

3:16 What is nuclear fusion, and maybe what is nuclear fission?

3:20 Let's lay out the basics.

3:23 So fusion is what powers the universe.

3:25 Fusion is what happens in stars and it's where the vast amount of energy

3:30 that we use today here on Earth comes from the process of fusion.

3:35 It also is what powers plants.

3:37 And those plants become oil, and those become fossil fuels that then powers

3:42 the rest of human civilization for the last 100 years.

3:47 And so fusion really underpins a lot of what

3:51 has enabled us as humans to go forward.

3:55 However, ironically,

3:56 we don't do it actively here on Earth to make electricity yet.

4:01 And so fundamentally, what fusion is,

4:04 is taking the most common elements in the universe:

4:07 hydrogen and lightweight isotopes of hydrogen and helium,

4:10 and fusing those together to make heavier elements.

4:13 In that process, as you combine atomic nuclei and form heavier nuclei,

4:19 those nuclei are slightly lighter than the sum of the parts.

4:23 And that comes from a lot of the details

4:26 of quantum mechanics and how those fundamental particles combine and interact.

4:31 We also talk about the strong nuclear force that holds the atomic

4:35 nuclei together as one of the fundamental forces involved in fusion.

4:39 But that mass defect, E=MC², we know from Einstein, is also energy.

4:45 And so, in that process, a tremendous amount of energy is released.

4:49 And the actual reactions, I think,

4:50 is a lot more interesting than simply it's a little bit lighter,

4:53 and therefore, energy is released.

4:55 But that's the fundamental process in fusion

4:57 as you're bringing those lightweight atomic nuclei, those isotopes together.

5:02 Fission is the exact opposite,

5:04 where you're taking the heaviest elements in the universe: uranium, plutonium,

5:08 things that are so heavy and have

5:11 so many internal protons and neutrons and electrons,

5:14 that they're barely held together at all.

5:17 They're fundamentally unstable or radioactive,

5:19 and those elements are very close to falling apart.

5:23 And as they do that, if you take a uranium 235 or a plutonium 239 nucleus,

5:28 and you add something new,

5:30 usually it's a neutron, a sub-atomic particle that's uncharged,

5:34 that unstable, that very large nuclei will then break into pieces.

5:38 Many pieces, a whole spectrum of pieces.

5:39 But if you add up all of those pieces,

5:41 they also have slightly less mass than the initial one did,

5:46 the initial uranium or plutonium.

5:47 And in that process, again, E=MC², a tremendous amount of energy is released.

5:53 There's a very famous curve in atomic physics,

5:56 fusion or fission, looking at the periodic table.

5:59 Going from the lightest elements, hydrogen,

6:01 to the heaviest elements, those uranium, plutonium, and others.

6:05 And fusion happens up to iron.

6:07 Iron is the magical point in between

6:10 where lighter elements than iron fuse together,

6:13 and heavier elements fission or are fissile and break apart and release energy.

6:20 I think about and I look at that process in stars,

6:24 in that our star is fundamentally

6:27 an early stage star that's burning just hydrogens.

6:30 But when it burns and does fusion, those hydrogens combine into heliums,

6:35 and later stage stars can then burn those heliums and they

6:38 can fuse those together to form even heavier elements and carbons.

6:42 And those carbons can fuse together and form heavier elements.

6:46 And that whole stellar process is something that inspires

6:49 us at Helion to think about what are fusion fuels, not just the simplest ones,

6:55 but more advanced fusion fuels that we see in stars throughout the- Okay,

6:59 so there's a million things I want to say.

7:01 First, zooming out to the biggest possible picture,

7:03 if you look across hundreds of millions, billions of years,

7:06 and all the, my opinion, alien civilizations that are out there,

7:11 they're going to be powered likely by fusion.

7:14 So our advanced intelligent civilization is powered by fusion

7:16 in that the sun is our power plant.

7:22 Then the other thing is the physics.

7:24 Again, very basic, but you said E equals MC squared a couple times.

7:28 Can you explain this equation?

7:31 E=MC squared is a fundamental relationship that a patent clerk, Einstein,

7:33 discovered and unlocked an entire new realm of physics and engineering

7:39 and has shown us engineering and has shown us atomic physics,

7:46 what happens inside the nucleus,

7:47 and unlocked our understanding of the universe and paved

7:49 the way for many of the physics advancements that came after.

7:52 That we think about mass as these particles.

7:56 But in reality, at the same time, they're energy,

7:59 and there's a direct quantitative relationship between how

8:03 much energy is in all of that mass.

8:07 And in fact, all of the energy that is released,

8:09 even by atomic physics, certainly in atomic reactions, is E=MC squared.

8:12 I think most people have heard of and are used to this.

8:18 But also in chemistry and in chemical bonds, there is a change in mass.

8:21 When you take a those chemical bonds, there is a change in mass.

8:25 When you take a hydrogen and an oxygen

8:27 and you burn them and you combine them into water, there's a change in mass.

8:30 Now, that change per atom and per molecule is actually so small that it's

8:33 extremely hard to molecule is actually so

8:35 small that it's extremely hard to measure, but it's still there.

8:38 That's the energy that is released, and you can quantify that.

8:41 We use units of electron volts as a unit

8:42 of what is the energy in atomic processes or chemical processes.

8:53 Can you also just speak to the different fuels that you mentioned,

8:55 both on the fusion and fission side?

8:58 ...fission side?

8:58 So uranium, plutonium for the fission,

9:01 and then hydrogen isotopes for the fusion?

9:04 So for fission, uranium and plutonium, we don't make those nuclei.

9:07 Those, right now for humanity, make those nuclei.

9:10 Those, right now, for humanity,

9:12 those have been made in the primordial universe through super-supernova and Big

9:16 Bang and the initial formation of the universe where matter was created.

9:21 And so we dig those up.

9:24 We dig up uranium, plutonium out of the ground.

9:26 And in fact, most plutonium we make from uranium,

9:28 and we can talk about how to enrich uranium if we want to go down that road.

9:31 But that's how we get those molecules and nuclei.

9:35 For fusion materials, hydrogenic species,

9:38 or hydrogens are primordial in the universe.

9:40 Also, only the most common things that are in primordial in the universe.

9:44 Also only the most common things the universe.

9:47 The suns and stars are made up of hydrogens and heliums,

9:49 and so the vast majority of atoms in the universe still are hydrogen.

9:57 So the basic fuel for fission is already in the ground,

10:00 and then the basic fuel for fusion is everywhere.

10:03 Is everywhere, and we particularly use a type of hydrogen called deuterium,

10:07 which is a heavier isotope of hydrogen.

10:11 Hydrogen is typically one proton and one electron, atomic mass of one.

10:15 Deuterium is an atomic mass of two,

10:17 which is a proton, which is a charged particle,

10:20 and it has a neutron in its nucleus, which is an uncharged particle.

10:24 And so that's deuterium.

10:25 As the fuel now, deuterium is also found in all water on Earth,

10:28 in the water I'm drinking right now.

10:32 It's in my body.

10:34 It's in Coca-Cola.

10:35 It's everywhere.

10:37 And it's safe and clean and one

10:39 of those fundamental particles that was born in the cosmos,

10:42 and we estimate that in seawater here on Earth, we have,

10:46 if we powered at our current use of electricity, all of humanity on fusion,

10:52 somewhere between 100 million years and a billion years

10:55 of fuel in hydrogen and deuterium here on Earth.

11:00 And how is that stored mostly?

11:02 Mostly that's just in water.

11:04 Mostly it's a mix of, we call this actually heavy water,

11:07 where you have normal water that you're used to.

11:10 We talk about and you learn in school, is H2O,

11:13 where there's two hydrogens and oxygen in a nucleus in the molecule.

11:18 And deuterium, or heavy water, is D2O, two deuteriums and an oxygen.

11:23 In reality, it's actually an interesting mix where you have some HDO,

11:31 so a mix of hydrogen and deuterium.

11:56 You also have other hydrogen but also in chemistry and in chemical bonds,

12:15 that in those chemical bonds, there is a change in mass.

12:16 ...fission side?

12:16 So uranium, plutonium for the fission,

12:17 and then hydrogen isotopes for the fusion?

12:17 In terms of fuel, is that correct to say?

12:19 That's correct to say at today's power level.

12:21 I think what's interesting is the idea that as we deploy the same power

12:25 source that powers the universe here on Earth as humans, can we do more?

12:30 Can we have access to much more electricity,

12:33 and much more energy and do really interesting things with that?

12:36 And still there's large amounts, millions and millions of years of power even

12:41 at much higher output power levels for humanity.

12:45 Yeah, so the moment we start running out of hydrogen and helium,

12:49 that means we're doing some pretty incredible things with our technology.

12:54 And then that technology is probably going to allow us

12:57 to propagate out into the universe and then discover other sources.

13:00 Because you can also get it on other planets.

13:02 Whatever planets have water,

13:03 it looks more and more likely like a lot of them do.

13:07 What an incredible future,

13:09 just out into the cosmos, nuclear power plants everywhere.

13:13 Okay, so to linger on some of the technical stuff,

13:17 you said strong nuclear force.

13:19 So how exactly is the energy created?

13:22 So how does the E=MC squared, the M go to the E infusion?

13:31 So in fusion, you take these lightweight isotopes like hydrogen and deuterium,

13:35 and as you combine them and get them closer and closer together,

13:40 some really interesting fundamental physics happens.

13:42 So first these atomic nuclei are charged.

13:44 They have an electric these atomic nuclei are charged.

13:47 They have an electric charge, and they like charges repel.

13:51 And I think everybody is familiar

13:53 with that, where you take two positive charges,

13:55 and you try to push them together,

13:57 and the electromagnetic force between them repels them.

14:00 So you have a force that's actually pushing against them.

14:04 So in fusion, you work to get your fuel very hot,

14:07 very, very high temperatures, 100 million degree temperatures.

14:10 And temperature really is kinetic energy.

14:12 It's motion, it's velocity.

14:13 So that these particles are moving so fast that even

14:17 though they're coming together and there's this repulsive electromagnetic force,

14:20 they can still come close enough that another force comes into play,

14:24 which is the strong force.

14:25 And then once you get within a very close distance

14:29 on the order of the scale of those nuclei themselves, of those atomic nuclei.

14:33 So the tiniest thing you could imagine,

14:35 and probably way smaller than that, these particles then are

14:38 attracted to each other and they combine and they fuse together.

14:42 At that point, you create heavier atomic nuclei that have a slightly less mass,

14:47 slightly less total mass in the system,

14:51 and that mass equals MC squared as energy.

14:55 So extremely high temperature, extremely high speed.

14:58 Maybe that's one of the other differences also with fusion and fission,

15:02 is just the amount of temperature required for the reactions.

15:06 Is that accurate to say?

15:08 Yeah, and I think fundamentally it's that in a lot of ways,

15:11 fusion is hard and fission is easy.

15:14 Nuclear fission happens at room temperature,

15:17 that this uranium and plutonium is so likely to break

15:21 apart already that simply the adding of one of these neutrons,

15:25 one extra particle will then break it apart and release energy.

15:29 And if you have a lot of them together, it will create a chain reaction.

15:33 Fusion, that doesn't happen at all.

15:35 Fusion is actually really hard to do.

15:38 You have to overcome those electromagnetic forces

15:40 to have a single fusion reaction happen.

15:42 And so it takes things like in our sun

15:45 we have what is called gravitational confinement, where the gravity,

15:48 literally the mass of the fuel itself is pulling

15:52 to the center of the sun and it's pulling.

15:54 And so there's a large force that's pulling

15:57 all that fuel together and holding it and confining

16:00 it together such that it gets close enough

16:03 and hot enough for long enough that fusion happens.

16:07 And then we have to figure out if we're building fusion reactors,

16:10 we have to figure out how to do

16:13 that confinement without the huge size gravity of the sun.

16:18 That's right.

16:19 Obviously, the sun is vastly larger than Earth,

16:22 and so we can't do that same process here on Earth.

16:25 Yet.

16:26 No, I'm just kidding.

16:26 All right.

16:27 But we have other forces we get to use.

16:29 We can use the electromagnetic force,

16:31 which the sun doesn't get to do, to apply those forces.

16:35 And I actually want to take a pause right there and point out a word.

16:39 Historically, we've used the word reactor around fusion,

16:41 but I don't think that's right.

16:43 And for me, we're really careful about this terminology.

16:47 When we look to how that word is defined,

16:50 and we can look to how the experts define it, it doesn't really apply to fusion.

16:55 So the Nuclear Regulatory Commission, the NRC,

16:58 defines reactor as, I have it right here,

17:01 "A nuclear reactor is an apparatus other than an atomic weapon,

17:06 designed or used to sustain nuclear fission in a self-supporting

17:09 chain reaction." And there's two big parts to that.

17:14 That one, fission reaction.

17:16 Obviously, fusion is not that, and we've talked about why,

17:19 but also the self-sustaining part.

17:21 In that a reactor is self-sustaining,

17:24 you take your hands off of it and it keeps going.

17:27 In fusion, that doesn't happen.

17:28 And we know because we have to do it every day and it's really hard to do.

17:33 And so we actually use the word generator,

17:35 because we don't talk about, for instance,

17:37 a natural gas reactor, is that if you stop putting in fuel, it turns off.

17:41 And the same thing happens in fusion.

17:43 And so we're pretty careful about making sure we talk

17:47 about that as a generator where you're putting in fuel,

17:50 you're getting electricity out.

17:51 And then when you stop putting in fuel, it just shuts off.

17:55 And you can go even one step further and say,

17:57 "What am I going to do with this fusion that powers the universe?

18:00 And what does humanity want out of this?" And what we want is electricity.

18:04 We don't simply want a set of reactions or even heat and energy.

18:08 That's great, but what I really want is electricity.

18:12 And yeah, we'll talk about the technical details

18:14 of one of the big benefits of the linear design of the approach that you do is

18:19 you get to electricity directly as quickly as possible.

18:21 And some of the other alternatives, have an intermediate step, and those again,

18:26 are technical details, but let me still linger on the difference between...

18:32 fusion and fission.

18:32 What are some advantages at a high level

18:35 of nuclear fusion as a source of energy?

18:38 fundamentally as a source of energy.

18:40 In fusion, you're taking these lightweight isotopes,

18:43 you're bringing them together,

18:45 you're releasing energy, and that energy is in the form of charged particles.

18:51 It's already in the form of electricity.

18:53 Fusion itself has electricity built into it without

18:56 a lot of the steam or thermal system requirements.

18:59 And so, that's a really nice fundamental benefit of fusion itself.

19:04 Also, this reaction that's really hard to do turns itself off,

19:08 so you end up with that fusion is fundamentally safe,

19:11 and that's really a key requirement of any industrial

19:14 system is that it turns itself off and is safe.

19:17 You turn the key off on your car, you know it's going to turn off.

19:20 I guess the flip side of that, just stating the obvious,

19:23 but it's nice to lay it out.

19:24 nice to lay it out.

19:25 For nuclear fission, it's a chain reaction,

19:27 so it's hard to shut off, reaction, so it's hard to shut off,

19:31 and it works by boiling water into steam,

19:32 by boiling water into steam, which spins turbines and produces electricity.

19:37 and produces electricity.

19:38 Can you talk through this process in a nuclear fission reactor?

19:41 process in a nuclear fission reactor?

19:43 In a nuclear fission reactor, you put enough of this fissile material,

19:48 uranium or plutonium, together such that as these unstable molecules,

19:53 these unstable atoms crack open and break apart, they release heat,

19:57 that the component parts of those are actually quite hot.

20:01 And so not only are the component parts that the uranium breaks

20:04 into, and it's a whole spectrum of different atoms and atomic nuclei,

20:06 and it's a whole spectrum of different atoms and atomic nuclei,

20:08 are hot, but it also releases neutrons.

20:10 are hot, but it also releases neutrons.

20:12 It also releases more of these uncharged particles.

20:14 more of these uncharged particles.

20:14 And if you do it right,

20:16 this fissile material will be next to other fissile material,

20:18 this fissile material will be next to other fissile material,

20:19 and so that neutron will then go and bombard another

20:21 and so that neutron will then go and bombard another uranium nucleus,

20:24 again opening that up and releasing uranium nucleus,

20:26 again opening that up and releasing more heat and more of these neutrons.

20:29 more heat and more of these neutrons.

20:30 And that's how you have those reactions of a self-supporting chain reaction,

20:33 those reactions of a self-supporting chain reaction,

20:35 and that chain reaction then continues.

20:37 and that chain reaction then continues.

20:38 People design fission reactors such that you have

20:40 just the right balance fission reactors such that you

20:42 have just the right balance of enough neutrons

20:43 are made such that the reaction is continuing,

20:44 of enough neutrons are made such that the reaction is continuing,

20:46 but not so many neutrons are made that it speeds up.

20:48 because you don't want it to speed up.

20:50 And there's some kind of cooling mechanisms also?

20:52 Like, that's part of the art and the engineering of it?

20:55 and the engineering of it?

20:56 And then the key is at the same time,

20:58 you want to make sure that the whole thing is in water,

20:59 is typically the cooling fluid.

21:00 whole thing is in water, is typically the cooling fluid.

21:02 There's some more advanced fission reactors that have different cooling fluids,

21:04 advanced fission reactors that have different cooling fluids,

21:06 but water typically,

21:06 where then that absorbs that both the heat but water typically,

21:08 where then that absorbs that both the heat and those extra neutrons.

21:10 And so you use the water and the fluid to then extra neutrons.

21:12 And so you use the water and the fluid

21:14 to then run a steam turbine to do traditional

21:15 electricity generation run a steam turbine to do traditional

21:17 electricity generation and output electricity through your steam turbine.

21:19 and output electricity through your steam turbine.

21:21 You end up with complicated systems of flowing liquids and flowing water,

21:23 up with complicated systems of flowing

21:25 liquids and flowing water, balancing the heat.

21:27 balancing the heat.

21:28 A lot of fission reactor design comes from that thermal balance of keeping

21:30 this reaction comes from that thermal balance of keeping this reaction going,

21:33 making sure it doesn't speed up, because that's going,

21:35 making sure it doesn't speed up, because that's an uncontrolled chain reaction,

21:37 which you would not want, an uncontrolled chain reaction,

21:39 which you would not want,

21:40 and balancing the cooling and the output of getting the water out of it.

21:42 want, and balancing the cooling and the output of getting the water out of it.

21:48 So we should say that for reasons you already laid out,

21:50 maybe you can speak to it a bit more,

21:52 maybe you can speak to it a bit more, is nuclear fusion is much safer.

21:55 So there's no chain is much safer.

21:56 So there's no chain reaction going on.

21:58 You can just shut it off.

21:59 You can just shut it off.

22:00 But it should also be said that as far as I understand,

22:02 the current fission nuclear reactors as far as I understand,

22:04 the current fission nuclear reactors are also very safe.

22:07 are also very safe.

22:08 I think there's a perception that nuclear

22:09 fission reactors are unsafe, they're dangerous.

22:10 fission reactors are unsafe, they're dangerous.

22:12 And if you just look empirically at the statistics,

22:14 look empirically at the statistics,

22:15 that the fear is not justified by the actual safety data.

22:18 by the actual safety data.

22:19 Can you just speak to that a little bit?

22:22 Yeah.

22:22 We've been talking about the reaction processes themselves,

22:24 but I think fundamentally,

22:26 fundamentally, let's take a step back and look a little broader and say,

22:28 "Let's look at what we care about," look at what we care about,

22:30 which is the power plant, making electricity.

22:31 And I look at this from a nuclear engineer's point of view.

22:33 this from a nuclear engineer's point of view.

22:35 I spent a lot of years studying these systems.

22:37 studying these systems.

22:38 And modern fission reactors, I believe, are engineered to be safe.

22:41 believe, are engineered to be safe.

22:42 They're engineered in ways where as those reactions maybe speed up

22:45 where as those reactions maybe speed up and those systems get hotter,

22:50 and those systems get hotter,

22:51 they actually are built to expand and cool down passively and natively.

22:53 cool down passively and natively.

22:55 And there's protection systems in place that modern systems are quite

22:57 safe place that modern systems are quite safe from an engineering perspective.

23:01 perspective.

23:02 And so I believe that we have figured out

23:04 how to build nuclear fission reactors in a way

23:05 build nuclear fission reactors in a way where

23:07 the engineering of the power plant is safe.

23:09 plant is safe.

23:10 I would say that I look back at the history of what we've built over time,

23:13 of what we've built over time,

23:15 and the challenge hasn't come to the engineering actually.

23:17 engineering actually.

23:17 I believe the engineers have solved these problems.

23:19 The problem comes from humans, The problem comes from humans,

23:22 and the problem comes from other things around nuclear power.

23:24 comes from other things around nuclear power.

23:26 You have to enrich that uranium to put it in a plant.

23:28 enrich that uranium to put it in a plant.

23:30 And the plant's safe, but you had to enrich that uranium,

23:32 but you had to enrich that uranium, and that is some of the problem.

23:35 Or a plant is designed to run Or a plant

23:37 is designed to run for a certain number of decades safely,

23:39 but do we run it longer than that?

23:40 but do we run it longer than that?

23:41 And so those are where I think the real challenges happen,

23:43 the real challenges happen, is more with the humans around these systems

23:46 than the engineering of the power plants themselves.

23:47 than the engineering of the power plants themselves.

23:50 Well, I have to ask then, what do you think happened in Chernobyl?

23:52 What lessons do we learn from Chernobyl What lessons do we learn

23:55 from Chernobyl nuclear disaster and maybe

23:56 also Three Mile Island and Fukushima accidents?

23:57 Fukushima accidents?

23:58 I think you're suggesting that it has to do with the humans a bit.

24:01 humans a bit.

24:03 So with Chernobyl and Fukushima,

24:04 I actually put Three Mile Island in a different category.

24:06 in a different category.

24:07 In fact, some of the recent news in the last

24:09 year is that we're gonna be restarting Three Mile Island,

24:10 year is that we're gonna be restarting Three Mile Island,

24:12 because there's such a need for clean base load power.

24:14 such a need for clean base load power.

24:16 So that's actually a very interesting other topic we should talk about,

24:18 interesting other topic we should talk about, is why and how we're doing that.

24:21 But more than that, But more than that, going back

24:23 to the accidents that did happen in both of those systems,

24:25 you can point to in both of those systems, you can point to the human failure

24:29 rather than the engineering failures of those systems.

24:31 the human failure rather than the engineering failures of those systems.

24:34 That in Fukushima specifically, That in Fukushima specifically,

24:36 there were multiple nuclear fission reactors on the same site that successfully

24:39 reactors on the same site that successfully kept running through the tsunami,

24:42 totally successfully, the tsunami, totally successfully,

24:44 and were only later shut down for more political reasons.

24:47 more political reasons.

24:47 But the old one, the oldest of them that had been on site for long periods,

24:50 them that had been on site for long periods, and maybe, maybe too long,

24:52 I think some experts have looked at this in the past I think some experts

24:55 have looked at this in the past

24:56 was where some of the problems actually happened.

24:57 was where some of the problems actually happened.

25:01 And so, I look to that less as a failure of the engineering of the power plants,

25:08 engineering of the power plants, and more of the humans around those systems.

25:12 around those systems.

25:13 That we should be operating these plants as designed,

25:15 and then I believe they're safe.

25:16 these plants as designed, and then I believe they're safe.

25:18 And that gets to some of the atomic weapons questions

25:20 And that gets to some of the atomic weapons questions that I

25:22 think are the other part around nuclear reactors are the other

25:25 part around nuclear reactors and fission reactors that are concerning for me.

25:30 Can you speak to those?

25:31 So, maybe this is a good place to also lay out the difference between

25:33 nuclear fission lay out the difference between

25:35 nuclear fission power plants and nuclear fission weapons,

25:39 power plants and nuclear fission weapons,

25:42 and maybe also nuclear fusion power plants and nuclear fusion weapons.

25:50 Like, what are the differences here?

25:53 Fusion power plants can't be used to make nuclear weapons.

25:59 Fundamentally, the processes in fusion aren't the same

26:03 processes that happen in nuclear bombs and nuclear weapons.

26:06 It's actually one reason I started in fusion,

26:10 and most of our team thinks about the mission of fusion,

26:14 of delivering clean, safe electricity, is it also can't be used to make weapons.

26:19 And I think that's a little bit

26:21 of a distinction from traditional nuclear fission reactors,

26:25 is that while I totally believe as a nuclear engineer,

26:28 we can build power plants now that are safe,

26:31 that aren't going to have reactions.

26:33 They use a fuel, uranium and plutonium,

26:36 that can be used to make nuclear weapons.

26:40 We know that if you take enough fissile material together,

26:44 enough uranium and plutonium,

26:45 put it in a small volume, that it will not just create a reaction,

26:50 but it will create a supercritical reaction that will then continue

26:53 and grow and release a tremendous amount of energy all at once.

26:56 And that is a bomb.

26:57 That is a bad situation, and that is what we want to avoid.

27:01 A lot of the key is recognizing

27:02 that even though there are things called fusion bombs,

27:05 the H-bomb, the hydrogen bomb, the hydrogen bomb has uranium in it.

27:10 It's still a fission bomb.

27:12 So, fundamentally, this works because you have a fission reaction, a primary,

27:18 and that creates radiation that induces a fusion reaction with a small

27:24 amount of fusion fuel that then boosts that uranium reaction again.

27:29 And so most of the energy, in fact 90% of the energy in an H-bomb,

27:34 is all still from the uranium reactions themselves.

27:37 Yeah, I think people call it a nuclear fusion bomb,

27:40 a hydrogen bomb, but really it's still a nuclear fission bomb.

27:43 It's just that fusion is a part of the process to make it more powerful,

27:47 but you still need, like you said, the uranium fuel.

27:50 So it's not accurate to think of it as a fusion bomb really.

27:54 And if you take away that fissile material,

27:57 that nuclear fission reaction, the fusion reaction doesn't happen at all.

28:01 In fact, researchers have over the decades tried to make

28:07 an all fusion bomb and been very unsuccessful at it.

28:10 The physics and the engineering don't support

28:12 it can ever happen with our understanding today.

28:14 The topic we're talking about is more broadly called proliferation,

28:18 and this is the creation of nuclear weapons

28:22 in the world and the distribution of those weapons.

28:25 And something we know as physicists and engineers is

28:29 that fusion can't be used to make nuclear weapons.

28:32 We know that.

28:34 But that is not sort of widely known.

28:37 And part of what we went out to do

28:40 is work with the proliferation experts in the world,

28:43 the people who work to prevent nuclear weapons from being made, being created,

28:47 being shared throughout the world,

28:49 because we know the challenges, the geopolitical challenges that happen.

28:52 And we went to those proliferation experts, and we were worried they would have

28:57 the sort of the same historical question of, like,

29:00 "Well, the word nuclear is in fusion,

29:02 so therefore it must be related." And, and in fact, the total opposite happened.

29:08 What they told us is, "Please,

29:10 please go develop fusion power plants absolutely as fast as possible.

29:14 The world needs this." And the proliferation experts were telling

29:19 us that otherwise people would start enriching uranium throughout the world,

29:24 and we'd be building enriched uranium power plants because

29:26 we need the electricity that's clean and base load.

29:30 But in those processes,

29:31 they'll be making fuel that could be one day used for atomic weapons,

29:35 for nuclear weapons,

29:36 and they were worried that, that the growth of this enriched uranium,

29:40 think about the centrifuges, that having a lot more centrifuges happening all

29:44 over the world would lead to more weapons, at least the possibility of it.

29:49 And so they are pushing us as fast as possible,

29:52 go build fusion generators and get them deployed everywhere.

29:54 Not just in the United States, but all over the world so that we're

29:59 building fusion power and that's meeting humanity's needs, not this other thing.

30:04 And so I was really pleasantly surprised.

30:06 We've written a number of papers and worked

30:08 with those communities on this of what does it mean,

30:12 how is fusion power safe and can't be used for nuclear weapons.

30:18 So, this might be interesting to ask on the geopolitics side of things.

30:21 I have the chance to interview a few world leaders coming up.

30:24 By way of advice, what questions should I ask

30:27 world leaders to figure out the geopolitics of nuclear, nuclear proliferation.

30:35 ...nuclear weapons, nuclear fission power plants,

30:39 and nuclear fusion power plants?

30:41 What's the interesting,

30:42 intricate complexity there that you could maybe speak to?

30:47 The question I would want to ask is,

30:50 "What would you do if we could deliver for you low-cost,

30:55 clean, industrial scale,

30:57 tens or hundreds of megawatts of fusion power that's low-cost, clean,

31:05 baseload and doesn't have the geopolitical

31:08 consequences of uranium and plutonium,

31:10 of fissile material, what would you do there?

31:14 How would that change your view of the next 30 years?

31:18 But also, there's a lot of geopolitics connected to oil,

31:21 natural gas- ...and other sources of energy

31:23 which I think are important in Saudi Arabia, in the Middle East, in Russia.

31:28 I mean, all across the world.

31:30 And that's interesting too.

31:31 So do you think actually if everybody has nuclear fusion power plants,

31:36 that alleviates some of the geopolitical tension that have to do with energy,

31:41 other energy sources?

31:43 I certainly do, that the fuel is in seawater all over Earth.

31:46 Everybody has deuterium.

31:47 And everybody has it.

31:50 And so you can't have a monopoly on the fuel.

31:53 And no one can control the fuel and no one can turn off the fuel,

31:55 no one can cut a pipeline.

31:57 That just cannot happen with fusion.

32:00 And so if we can deploy those plants and we can deploy them quickly,

32:04 then it decouples the ability of any one or any few countries to control energy.

32:12 Okay, so let's sort of return to the basic question,

32:14 we already mentioned it a little bit, but is nuclear fusion safe?

32:21 So the power plants that we're talking about,

32:24 fusion power plants, are they safe?

32:26 Yes.

32:27 Fusion power is fundamentally safe.

32:29 The physics and the reactions of the fusion

32:33 system itself means you don't have runaways.

32:35 And so we've talked about some of the human factors

32:38 around power plants and power systems and industrial scale systems.

32:42 And that's something that we build into the design of these from today.

32:48 We look at, "How these systems might fail?" And in fact,

32:54 some of the analysis we do is we did this analysis

32:58 for the Nuclear Regulatory Commission over the last few years,

33:02 looking at how do you regulate fusion power.

33:05 As we're building the first fusion power plant,

33:07 we need to make sure we're regulated safely.

33:09 And so we spent a lot of time doing

33:11 the technical case and the political case in the United States,

33:14 of how to regulate fusion.

33:17 And so the analysis we did is assume

33:20 you have a fusion power plant that's operating.

33:23 And then at any one time, a meteor strikes it.

33:25 The whole thing is vaporized.

33:27 What is the impact of that?

33:28 So this is worse than you could ever imagine an actual physical scenario,

33:33 but let's start there.

33:35 And the answer is, you don't need

33:37 to evacuate the populace nearby the fusion power plant.

33:41 And one of the keys, I think,

33:44 that I come to when I think about this is the fuel.

33:48 In that, in a fusion generator,

33:51 you are continuously feeding in this hydrogen, these deuterium fuels.

33:57 And at any one time in a Helion fusion system,

34:00 and most fusion systems, you have one second of fuel in that system.

34:06 And so what that means is if you

34:08 stop putting fuel into that system, fusion just stops.

34:11 But what it also means is that if

34:14 something really catastrophic happened and, for whatever reason,

34:17 you have all that fuel that's not in the system.

34:20 And fusion is so hard to make happen.

34:22 You hit it with a meteor,

34:24 you do anything of that nature, and fusion doesn't happen.

34:28 That hydrogen, that heavy water, that deuterium,

34:30 just goes back into the environment safely and cleanly without issue.

34:34 And so that's the fundamental safety mechanism of fusion,

34:38 and you can compare that with other types of power plants,

34:42 oil or a coal power plant.

34:44 You might have a large pile of coal that then catches fire and burns.

34:47 And it's not catastrophic, but you have a large coal fire for a long

34:50 time releasing toxic fumes that you may have to deal with.

34:54 And in nuclear power, in a fission power plant,

34:57 you may have several years of fuel sitting in the core.

34:59 And in that case, if something bad happened,

35:01 you have all that potential energy for things to happen.

35:05 But in fusion, you have literally one second of fuel at any time in the system.

35:10 And having a tank of deuterium,

35:11 which we have around all the time, can't do fusion by itself.

35:15 It needs that complex system.

35:18 I love that there's, like, a PowerPoint going on in a secret meeting about

35:21 what happens if a meteor hits a fusion power plant.

35:25 Okay, so that's really interesting.

35:26 What about the waste?

35:28 What kind of waste is there for fusion power plants?

35:31 So the fusion reaction itself is still fundamentally an atomic reaction.

35:35 And so during this reaction, you do create ionizing radiation.

35:39 You create X-rays, you create neutrons,

35:40 and you create all these charged particles.

35:42 The charged particles themselves for a fusion reaction

35:45 are all contained in the- the fusion system.

35:49 And the X-rays, similar to think about a dentist office,

35:54 although a lot more than that, but that type of same

35:57 X-ray and X-ray energy is absorbed by the fusion system.

35:59 But the thing we do care about is those neutrons.

36:02 And so we do have, in a fusion system, activation.

36:05 We have, during its operation, neutrons are made and leave,

36:08 and so we have to shield these fusion systems during their operation.

36:13 and so this is very similar, in fact, this is a lot of the work we did

36:17 with the Nuclear Regulatory Commission over the last number of years.

36:21 That there was a landmark agreement that happened for the NRC

36:24 that then was codified into law last year called the ADVANCE Act,

36:28 which is really powerful because it says for the very first time-...

36:32 how the US government,

36:33 leading the way on this, which I'm really proud of, will regulate fusion.

36:37 And this gets into a little bit of the details,

36:40 but the way the Nuclear Regulatory Commission regulates nuclear things

36:44 in the United States is in these different sets of statutes.

36:49 And nuclear is in these different sets of statutes.

36:51 And nuclear reactors are regulated under something called Part 50.

36:53 And there's a lot of variety of the regulatory language around

36:56 that, but most of it is to handle special nuclear materials,

37:00 uranium and plutonium.

37:01 But fusion is not.

37:03 Fusion is regulated under something called Part 30.

37:06 And Part 30 is how hospitals are regulated,

37:09 particle accelerators, other types of irradiators where as they're operating,

37:13 you have very high energy particles, ionizing radiation,

37:16 and you have to protect operators from it.

37:18 And you have to shield them, and so we build concrete shields.

37:21 And if you came and visited Helion, you would see plastic, Plastic,

37:25 borated polyethylene and concrete shielding, To protect operators and equipment

37:30 from the fusion reactions while they're happening.

37:32 But again, you turn them off, and those fusion reactions stop.

37:36 And that's really the key.

37:39 There's a funny story related to that.

37:42 We, We've been building fusion systems that do fusion a long time,

37:47 and a- at some level, we- they got powerful enough doing enough fusion,

37:52 we started building these shields

37:53 and- and shielding them like a particle accelerator.

37:57 And I went to the regulatory bodies that regulate Part 30.

38:02 This is in Washington state.

38:03 It's the Department of Health.

38:05 And so I went to the Department of Health and said,

38:07 "Here's an application for a fusion generator shielding

38:11 permit as- as a particle accelerator." And uh,

38:15 the very first question I got asked was, "Great,

38:17 where do the patients go?" Because the standard form had a patient,

38:22 As a hospital, the patient dose for the particle accelerator,

38:25 and then the shielding.

38:26 And we talked all about the shielding and the operators,

38:29 which is very similar for a Helion system.

38:30 We said, "No, no patients at all.

38:32 No one's inside this thing.

38:33 Our goal is to generate electricity one day." This was a lot of years ago.

38:38 And we were able to go through and work

38:40 with the state agencies to license these fusion particle accelerators.

38:44 We were, as far as we know, the first licensed fusion system ever

38:49 as a particle accelerator for those first systems.

38:53 The first license we had was in 2020.

38:57 We then have gone on and now license several

38:59 of our fusion systems that we've built that do fusion,

39:02 both the shielding as well as some of the fuel processes.

39:08 So high level, what are the different

39:10 ways to build a nuclear fusion power plant?

39:13 Can you explain what a tokamak is, what a stellarator is,

39:19 and what's the linear approach that Helion is using?

39:25 So there are a number of ways to do fusion.

39:29 And fundamentally, in all fusion approaches,

39:31 you're trying to do the same fundamental physical process,

39:35 which is take these lightweight isotopes,

39:37 heat them up, so that they can move at high velocity,

39:41 over 100 million degrees, bring enough of them together.

39:44 We call it density.

39:46 Enough of them together in a certain volume,

39:48 so that you have reactions happening at a higher rate,

39:52 and keep them together long enough that they are able

39:55 to collide into each other and do fusion and release energy.

39:59 That's the fundamental core.

40:00 Now, how you do that, how you bring those particles together,

40:04 how you hold them together long enough,

40:06 there's a wide range of technologies that, as humans,

40:09 we've been exploring since the 1950s.

40:12 And I think about several main categories.

40:15 If you look at the fusion funding out there, government funding in the world,

40:19 private funding actually has quite a different profile,

40:22 which is an interesting thing to talk about.

40:25 But in public funding, in federal funding in the United States,

40:28 there's two mainline programs called inertial fusion and magnetic fusion.

40:33 And in inertial fusion, what you're trying to do is bring together

40:38 and push together by a variety of means, physical means, those particles.

40:42 You push them together.

40:44 The most common is called laser inertial fusion.

40:48 Our colleagues at the National Ignition Facility did

40:50 this really well and made world records in the last

40:53 few years for being able to demonstrate you can do this and do it at scale.

40:58 Where you take very high power lasers and pulse them

41:01 together to combine them to do fusion for a pulse,

41:04 for a very short period of time.

41:07 Nanoseconds, billionths of a second.

41:09 The other extreme, and you mentioned tokamaks and stellarators.

41:14 Stellarators are actually my favorite.

41:16 So we'll talk about those.

41:17 As a graduate student in fusion,

41:19 the stellarator is the first thing you learn about.

41:21 Because there's a mathematical solution for a stellarator that solves perfectly.

41:26 And you can write it out and you can solve it,

41:29 and analytically, it's very simple.

41:31 Building one is very hard.

41:34 And so it's taken humanity a number of decades

41:38 to be able to build stellarators and we

41:40 can do it now with the Wendelstein 7-X that came online in the last few years,

41:46 being the premier stellarator in the world.

41:50 I should say, all the different ways to do

41:52 fusion all just look so badass in terms of engineering.

41:57 Creating this containment, extremely high temperature, high density.

42:02 Everything's moving super fast.

42:05 Everything is happening super fast.

42:06 It's just fascinating that humans are able to do it.

42:09 Like, there are certain things, accelerators of that a little bit,

42:12 but this is even cooler,

42:13 because you're generating energy that can power humanity with this machine.

42:18 Anyway, can you just speak a little bit

42:20 more to the inertial and the magnetic fusion systems?

42:23 In a magnetic system,

42:25 your goal is not to push together those particles as fast as possible.

42:31 Your goal is to hold on to them for as long as possible.

42:34 And to do that, we use magnetic fields.

42:36 So let's take a step back.

42:38 What is a magnetic field?

42:39 So in an electromagnet, there are a variety of ways to make a magnetic field.

42:45 One of the most famous, I think everyone is familiar with, is Earth itself.

42:48 Earth has what we call the magnetosphere,

42:51 which is the magnetic protection that's generated

42:55 actually by the core of the Earth.

42:56 But we have a magnetic field around the Earth,

43:00 and that magnetic field protects us from particles coming from the galaxy,

43:06 galactic cosmic rays and solar particles that would come to Earth.

43:11 That magnetic field when you run a compass,

43:13 you see the magnetic field from the Earth.

43:15 So we know it's happening.

43:16 It's all over.

43:16 But how we generate it with electric currents is a little bit different.

43:20 And what we do is that we have a loop of wire,

43:24 and the simplest way to think about it is literally a round loop.

43:27 And in that loop, you have electrons.

43:29 You have electrical current that's running.

43:31 And when electrical current,

43:33 this is some of Maxwell's equations that we discovered in the 1800s,

43:36 that when you have an electrical current in a wire,

43:39 it generates a magnetic field inside that wire.

43:42 And so when you look at fusion systems,

43:46 you always have these big magnetic coils with large amounts of current.

43:50 We don't run a little bit of current.

43:52 In our systems, we have hundreds of mega amps of current.

43:54 If you think about at your house,

43:57 you have your breaker box with 200 amps or maybe a 400 amp breaker box,

44:03 and we run 100 million amps of electrical current.

44:06 So massive amounts of electrical current to be able to do this.

44:10 So that magnetic field that's generated inside

44:13 that magnetic coil has some really special properties,

44:16 and we take advantage of those properties to do fusion.

44:20 And some of those properties are not intuitive.

44:23 So here's one of my favorites.

44:25 When you have an electromagnetic field,

44:27 you have this coil with electricity going around it

44:30 and you have a magnetic field inside of it, and then you have a test particle,

44:35 a charged particle, an electron or an ion, which is,

44:39 if you imagine to generate this, I have a coil with electrons moving around it.

44:43 But if I put one in the middle of it,

44:46 in this magnetic field, some really interesting things happen.

44:49 That electron or that ion, that charged particle is what's called magnetized.

44:53 And what magnetized means is that it's trapped on that field line.

44:58 In fact, even really more interesting is

45:00 that it oscillates around that field line.

45:02 And so the way I think about this is

45:05 if you think about the Earth's magnetosphere again,

45:07 and you think about the charged particles, the aurora, the northern lights,

45:11 is a charged particle trapped in the Earth's

45:14 magnetic field going around the Earth's magnetic field.

45:18 And in the same way, in fusion, we do the same thing here on Earth,

45:21 but in a smaller direction where we trap these particles on magnetic fields,

45:25 and they can go around and stay trapped to that magnetic field line.

45:29 How much of the physics at this scale is understood here?

45:34 Like, how these systems behave when you attract a magnetic field in this way?

45:40 Like, is this fundamentally now an engineering problem,

45:44 or is there a new physics to be discovered about how the system is behaving?

45:49 In fusion, the physics we're using is actually quite old.

45:53 The fundamental electromagnetic physics is 1800s physics.

45:56 The fundamental atomic physics is early 1900s.

45:59 And so the fundamental physics of how these work is very well understood.

46:04 Putting them all together into a power plant, that's hard.

46:08 You can do the math.

46:11 Every introductory grad student does the math on a stellarator and says,

46:14 "This is all I need to do.

46:15 I just need to make a magnetic coil in this very complicated shape.

46:20 And then fusion will happen." However,

46:23 doing that in practice is actually quite challenging.

46:27 So maybe you could speak a little bit more.

46:29 So the stellarator and the tokamak, what's the difference between those two?

46:33 They're both magnetic fusion systems?

46:35 And then what does Helion do?

46:38 The tokamak and the stellarator are both magnetic systems.

46:41 Their goal is to generate this magnetic field

46:45 and hold onto the fusion fuel long enough.

46:48 Like I mentioned, these charged particles are trapped on the magnetic field.

46:52 In fact, they're oscillating.

46:53 We call that a gyro orbit,

46:55 is the radius that they oscillate around this magnetic field.

46:58 And we've been talking about atomic physics,

47:01 where everything is at this nanoscale.

47:03 But gyro orbits are not.

47:05 Gyro orbits for these fusion particles are measured in inches.

47:08 And so they're in, on a scale that we

47:11 can see and measure and understand really intuitively.

47:15 And in a magnetic system, your goal is to simply trap as many

47:19 of these particles as you can for long enough,

47:22 and heat them so they're hot enough so that they bang into each other.

47:26 They collide enough that you're doing fusion.

47:28 And you're doing enough fusion to overcome

47:30 as fast as you're losing those particles.

47:32 And so that's what happens when you put particles

47:35 in a magnetic field and you try to hold onto it.

47:38 The challenge is that it's really hard to hold onto them long enough.

47:41 These particles are moving around.

47:43 They're moving at very high velocity, millions of miles per hour.

47:46 They're colliding with each other and they're

47:48 getting knocked off and getting knocked away.

47:50 So we've talked about inertial fusion,

47:53 where you try to confine a fusion plasma by crushing it as fast as possible.

48:00 And magnetic fusion, where you just simply have a magnetic field and your goal

48:03 is to hold onto it for as long as possible.

48:06 But there's another way to do fusion, and in some ways,

48:10 it's one of the earliest approaches for fusion that was successful.

48:14 As scientists and engineers, maybe we're not too creative with the terminology.

48:18 We call the technique We call

48:20 the technique that Helion uses magneto inertial fusion,

48:22 because it does a little bit of both.

48:25 So to understand that, we can actually go back in history a little

48:28 bit and think about the evolution of some of these approaches to fusion.

48:32 And so from our perspective, we look at the technology that we use as built

48:37 on physics experiments that were very successful in the 1950s.

48:42 And in those systems, the earliest pioneers of fusion said,

48:46 "I know, we understand the physics.

48:49 We have to take these gases,

48:51 heat them to 100 million degrees, and then confine them,

48:54 push them together so that fusion happens." And so,

48:57 what is the best way to do that?

48:59 So some of the earliest programs we call them theta pinch.

49:02 And what those programs were, were a linear topology,

49:05 because we knew how to build these magnets.

49:07 It's called a solenoid, where you take a series of electric coils,

49:11 you run electrical current through them, that generates a magnetic field.

49:14 Great, so you have a magnetic field.

49:16 Now you add your fusion particles.

49:18 Okay?

49:18 So you've added fusion particles to this solenoid.

49:22 Here's the challenge.

49:23 Those particles, as they're sitting in that magnetic

49:26 field in this nice magnet, escape.

49:28 They leave out the ends, 'cause there's nothing holding them in.

49:31 Great.

49:31 So that makes sense.

49:33 And so that doesn't work, okay?

49:35 So then the next approach is to say, "Well, one branch of fusion said,

49:39 'Okay, well, to solve that, why don't we take the solenoid and bend it around?

49:43 Let's just make it a big donut.

49:44 So as they're escaping, they go around and around in a circle.' Great.

49:48 That's a great approach.

49:49 And so one branch of fusion went down that direction.

49:53 And that became, that evolved into the stellarator and the tokamak.

49:57 Different ways of taking those solenoids and wrapping them

50:01 around so that the plasmas go 'round and 'round

50:03 in that magnetic field and are held- those charged

50:05 particles are held long enough that fusion happens.

50:08 But there's a different way to do it.

50:10 And so the theta pinch was what was born

50:12 in the 1950s of, "Take this magnetic field and, oh, they're trying to escape.

50:16 Great.

50:17 Let's not let them escape.

50:18 Let's close the bottle-" Mm-hmm.

50:20 "...let's close the ends." And so we make

50:22 the magnetic field much stronger at the ends.

50:24 This one was called the mirror.

50:25 And so the idea was that the particles would bounce in between.

50:29 And that worked, and they got hotter and hotter and hotter.

50:33 But guess what?

50:33 As you kind of would imagine, as this mirror topology, this linear topology,

50:38 the pressure increased inside, the particle pressure,

50:42 the particles tried to push back on the magnetic field.

50:45 They were trying to escape now.

50:46 They're trying, they're getting hotter and hotter.

50:48 And just as you imagine, hot gas in a balloon tries to get out the ends,

50:52 you could not hold it tight enough at the ends to keep those particles in.

50:56 And in fact, the problem is the hottest ones were the ones that would escape.

50:59 Mm-hmm.

50:59 And so you do a good job of heating it, and they'd all leave out the ends.

51:02 Okay?

51:02 So then the next iteration said, "Okay, well,

51:05 why don't we just not try to hold onto it very long?

51:08 Why don't we squeeze it?" And so rather

51:10 than just holding it constantly, let's now crush it.

51:13 So we built this solenoid, we pinched the ends, and then we crushed it.

51:18 And what I mean by crushing it is not actually, like,

51:22 crushing any magnets or changing the- the topology or moving any parts,

51:27 but just rapidly increasing the magnetic field.

51:29 And so going from a magnetic field that's

51:32 just holding it to now taking all those particles,

51:35 if you imagine they if you imagine they were streaming around together,

51:39 and then rapidly increasing the magnetic field so

51:41 that those particles get closer and closer together.

51:43 So you increase the density.

51:44 And now fusion starts to really happen.

51:47 And now fusion starts to really happen.

51:50 But they ended up hitting a technological limit.

51:53 So this is the part that- that I look back and I'm,

51:57 I look at the pioneers that, in 1958, there was some pioneering work done.

52:02 And this was in California, what later became Livermore Labs.

52:06 There was also some work done at other national labs too.

52:10 These were all federally funded programs to explore this theta pinch topology.

52:14 Can you just squeeze the plasma down fast enough, hard enough?

52:17 plasma down fast enough, hard enough?

52:19 This was 1958.

52:20 The transistor was sitting in the laboratory, and they were commuting,

52:25 they were turning on millions of amps of electrical current.

52:28 And they were doing it, we haven't talked about the time scales, time scales,

52:31 but they were doing it in millionths of a second:

52:34 microseconds, megahertz speeds.

52:36 And this was in 1958.

52:38 No transistor, no CPUs, and no electrical switches,

52:40 none of the things that I take for and and no electrical switches,

52:44 none of the things that I take for granted every day.

52:47 And so they were able to show

52:49 at that time the highest performing fusion systems.

52:51 They got to temperatures...

52:52 They didn't get to 100 million degrees,

52:54 not quite then, but they got to 50 million degrees.

52:57 They were outperforming everything else in fusion,

52:59 but they reached the technical limit where they just could not build it anymore.

53:03 And so they, the- those pioneers, went in a different direction,

53:09 and they started down the laser inertial path of saying like, "Okay,

53:12 well, we can't do these electromagnetic pinches,

53:16 but we now have inv- this new thing

53:19 has invented the laser," which turns on in nanoseconds.

53:22 It's fast.

53:22 It's interesting.

53:23 Let's go down that path.

53:24 And it's not...

53:25 You have to fast-forward a couple of decades to researchers found with some

53:30 of these theta pinches when they're operated in a very specific way,

53:34 something else happened, something new happened,

53:37 and that these plasmas where before they squeezed them very hard,

53:43 and just like squeezing a tube of toothpaste, they squirted out the ends.

53:46 Now it didn't squirt out the ends.

53:48 It actually pushed back.

53:49 It stayed confined.

53:50 It stayed trapped inside that linear topology.

53:53 Even though the ends were open, the plasma didn't leave.

53:56 And so there was a large amount of programs of, like,

54:00 "What is happening here?" This is an accidental

54:01 discovery in plasma physics that something new is happening.

54:05 And what we discovered is we now call the field reversed configuration.

54:09 there's numerous programs of FRC,

54:12 field reversed configuration programs both at national labs.

54:16 There's actually a number of private companies

54:18 now of people building field reversed configurations.

54:20 And they have some really unique properties,

54:23 but fundamentally, talking about the main difference,

54:26 I describe the solenoid with magnetic

54:28 fields throughout the center of that volume,

54:31 and plasma trapped going back and forth.

54:33 But some other things can happen, which is really interesting.

54:36 really interesting.

54:36 And what they discovered early is if they have field going in one direction,

54:42 so the plasma, the so the plasma,

54:44 the electrical current is going around the loop and the plasma is

54:49 going back and forth along this magnetic field line inside that solenoid,

54:53 inside that theta pinch.

54:55 But then they change the direction of the magnetic field.

54:59 And this is what we call field reversal, and this is really the key is that you

55:04 start with the plasma going in one direction,

55:06 and then very rapidly, you change the direction.

55:08 You change and reverse the direction of that field.

55:11 And something really interesting happens, which is the plasma, this fusion fuel,

55:15 these charged particles which are trapped on the magnetic

55:19 field lines that are moving back and forth, you change the direction.

55:23 What that means is that you're trying to take

55:26 that electrical current and that magnetic field and reverse its direction,

55:30 flip it, but it can't flip fast enough.

55:33 The plasma is sitting there and you can't move the particles.

55:36 And so what's really interesting is what

55:38 happens is that because the particles can't move,

55:42 but you've now flipped the direction of the magnetic field, you've inverted it.

55:45 Something really, really unique happens,

55:47 which is that the plasma itself reconnects internally.

55:50 And so now what you're left with is

55:55 an outside magnetic field, an electrical coil, and inside, the plasma,

56:01 where before it was moving along, it's now moving internally.

56:07 Rapidly reversing the magnetic field, plasma self-organizes into a closed field.

56:14 What?

56:14 So how...

56:16 It sounds wild.

56:18 It's, it's...

56:18 Yeah.

56:19 So, first of all, there's a million questions I have.

56:22 So one of them, what's rapidly?

56:24 What time scale are we talking about here?

56:28 Mm-hmm.

56:28 You have to reverse the electrical current faster than a millionth degree,

56:33 which is a very hot gas particle, can move.

56:37 Okay.

56:37 And so that means we have to do it on the order of a millionth of a second.

56:40 Wow.

56:41 We have to do it in a millionth of a second.

56:42 Wow.

56:43 And, and so in practice...

56:46 this is hard.

56:47 And it's only, we can only do it now because of semiconductor switching.

56:52 Because we can move things, we can switch things.

56:56 Like the transistor in every CPU in a computer switches at a gigahertz,

57:00 that means in a nanosecond, it's switching in a billionth of a second.

57:04 And so now, which we didn't in the 1950s when these theta pinches were invented,

57:07 but now we have the semiconductors to be able to do that.

57:10 The self-organizing plasma.

57:12 Can you just speak to that?

57:14 What the heck is it doing?

57:15 How do we discover, how do we understand the self-organizing mechanism,

57:19 the dynamics of the plasma that's able to contain itself?

57:23 So what I like to do is use an analogy here:

57:27 once you've made it, it's actually somewhat straightforward to understand.

57:32 Getting to it is tricky,

57:34 and how they discovered it the first time is absolutely amazing.

57:37 But once you've made it, it's a lot more straightforward to understand.

57:41 So it's a lot more straightforward to understand.

57:45 In a magnetic coil, when you have a round electrical coil,

57:48 you have electrical current flowing in that coil.

57:52 And if you have a conductor, if you have another, a metal inside that coil,

57:56 and this is called Lenz's Law in one of the Maxwell equations,

58:00 is that as you have electrons and you have current flowing in that coil,

58:05 an equal and opposite electrical current is induced in a piece of metal nearby.

58:11 This is the same thing that happens in a transformer where you

58:14 have a primary on a transformer and you have electricity flowing in it,

58:17 and you have a secondary where electricity flows exactly the opposite direction.

58:21 We use this every day in our lives.

58:23 And so in this condition, you have a conductor,

58:28 an electrical conductor where current can flow,

58:30 and you have an electrical current flowing on the outside,

58:33 electrical current flows on the inside.

58:35 And in that case, now, I've described two pieces of metal.

58:40 Now let's go one step further and that inner

58:42 conductor is not a piece of metal anymore.

58:44 It's one of these high temperature gases, this plasma, this charged particles.

58:49 So now you have electrical current flowing in the plasma.

58:53 This is really, really interesting.

58:55 We talked about these charges moving back and forth.

58:58 Well, moving electrical charges is current.

59:00 So in every plasma condition we've talked about, the tokamak,

59:04 the theta pinch, the stellarator,

59:06 there's electrical current flowing in the plasma.

59:09 But in the field-reversed configuration,

59:10 you have a lot of electrical current flowing in the plasma,

59:14 massive amounts of it.

59:15 And that's the key.

59:17 So you have the center core where

59:19 electrical current is flowing in this transformer,

59:22 if you want to think about it, primary and secondary.

59:24 And here's the craziest part of it.

59:27 This electrical current— Well, how did I describe a magnet?

59:31 An electromagnet is a loop that has electrical

59:33 current flowing in it that generates a magnetic field.

59:37 And for a theta pinch, and for a mirror and for a tokamak,

59:41 in that magnetic field, the plasma gets trapped.

59:44 But in an FRC, this electrical current is the plasma.

59:49 And that plasma plasma then generates its own magnetic field,

59:55 and it's then trapped on its own magnetic field.

59:59 That's fascinating.

1:00:00 And that's the key.

1:00:01 So, in your tokamak, in your donut, in your stell- in your funky donut,

1:00:05 your stellarator- ...you make the magnets and you trap your plasma in it.

1:00:09 In an FRC, you make the plasma, which makes the magnets, and it traps itself.

1:00:15 The craziest part of this, in my mind,

1:00:18 is that we actually see this in nature all the time.

1:00:22 If you look at the sun, we see solar flares.

1:00:25 In a solar flare, we've all seen the pictures of the photosphere

1:00:29 of the sun and this large arc of plasma coming out.

1:00:34 That plasma has current, electrical current flowing in it,

1:00:36 and then we see this solar flare rip off of the sun.

1:00:41 And that solar flare then can flow

1:00:43 throughout and continue into the solar system,

1:00:45 and for a little while anyway, it makes something called a plasmoid.

1:00:49 That plasmoid is in fact electrical current flowing in the plasma,

1:00:54 generating a magnetic field and holding it for longer than it would otherwise.

1:00:58 So, we've observed these for 100 years,

1:01:00 and we've known about these plasmoids for a long time,

1:01:03 and there's researchers that have tried intentionally to make them.

1:01:07 But fundamentally, that's what we do every day,

1:01:10 is make one of these self-organized closed-field plasmas.

1:01:15 in a more controlled way at this rapid rate of one-millionth

1:01:18 of a second and being able to make sure it's reliable,

1:01:21 stable, and all that kind of stuff.

1:01:23 So, by the way, how do you keep the thing stable?

1:01:26 And there's the hard part, because I just described a solar flare.

1:01:29 But, and yes, we've seen the pictures of them,

1:01:32 but we've also watched them, and they appear.

1:01:34 They fly away from the sun, and then they go away,

1:01:36 and that's not what we want in fusion, right?

1:01:38 We want to be able to control this.

1:01:39 That's the hard part of the job.

1:01:41 So, that's what we've spent the last number of years learning how to do,

1:01:47 ourselves and others, on these pulsed closed-field FRC systems.

1:01:53 Hm.

1:01:53 Let's first talk about how to make them,

1:01:55 and then we'll talk about how to make them stable,

1:01:57 because they're two different things, and we spend a lot of time on both.

1:02:00 So, we talked about timescales.

1:02:01 You have to reverse the field.

1:02:03 You have to change the electrical current in a millionth of a second.

1:02:06 So, how do you do that?

1:02:08 So, I've described this system as you have a series of magnets.

1:02:11 You have a magnetic field on the outside,

1:02:14 and then on the inside of this, you have this donut,

1:02:18 this FRC that has its own electrical current.

1:02:22 We didn't talk about this yet, but it's generated a magnetic field,

1:02:26 and that magnetic field has pressure,

1:02:27 and this is the other thing that's really interesting.

1:02:30 We talked about how this theta pinch compresses a magnetic field.

1:02:35 It applies a pressure on the outside.

1:02:38 But the plasma itself has a pressure on the inside,

1:02:41 and it has both a particle pressure, literally the particles bouncing.

1:02:45 Think about hot gas in a balloon.

1:02:47 The particles expanding,

1:02:48 the ideal gas law expanding and contracting inside a balloon.

1:02:50 But they also have a magnetic pressure.

1:02:53 The electromagnetism is pushing back,

1:02:56 and I like to think about this as the motor in a Tesla.

1:03:00 In your electric car, you have a motor, an electric motor,

1:03:04 and what that motor has is a series of windings.

1:03:06 Those windings, you flow electrical current, in this case from a battery.

1:03:10 Hit the gas, electricity flows from the battery

1:03:12 into the motor into those windings, and it generates an electromagnetic force.

1:03:16 A Lorentz force is what it's technically called.

1:03:20 This electromagnetic force induces an electrical

1:03:23 current on the armature, on the shaft.

1:03:26 This is getting into the details,

1:03:28 but in the armature of an electrical motor, that actually is what spins.

1:03:32 So the outside of a motor doesn't spin.

1:03:34 You flow electrical current through it, and the inside does spin.

1:03:37 That electromagnetic force is what is spinning that armature.

1:03:41 In our case, we're inducing an electrical force in that electromagnet,

1:03:45 and that's putting an electrical current,

1:03:48 just like in the armature, into that plasma.

1:03:50 And we can use that force to do interesting things.

1:03:54 So that electromagnetic force can compress the fusion plasma.

1:03:57 It can expand the fusion plasma.

1:03:59 But here's the problem, it's unstable.

1:04:02 So this is something you learn very early

1:04:05 in your graduate work as a student in fusion,

1:04:09 is you learn about plasmas that are called high beta plasmas.

1:04:14 So I keep seeing this plasma beta thing everywhere.

1:04:17 What is this ratio of plasma field energy to confining magnetic field energy?

1:04:21 Please explain.

1:04:23 Plasma beta is the ratio of the magnetic pressure to the particle pressure.

1:04:26 What that fundamentally means is I talked about how you have a magnetic field,

1:04:31 and in that magnetic field, plasma is trapped on that magnetic field.

1:04:37 But it's not very well trapped.

1:04:39 It can escape.

1:04:40 It can leave either down the ends, it can freely travel,

1:04:43 or it can also travel across the magnetic field.

1:04:46 And so we have a term called plasma beta,

1:04:50 which gives us an understanding of how well trapped that plasma is.

1:04:54 So, as you apply a magnetic pressure,

1:04:57 a magnetic field to this plasma, it pushes back,

1:05:00 and does it push back a little or does it push back a lot?

1:05:04 And for a field-reversed configuration, in one of our plasmas,

1:05:08 beta is very close to one.

1:05:10 In fact, usually by definition, one at any point in the system,

1:05:14 which means that every time I apply

1:05:16 a magnetic force on this donut to compress it,

1:05:19 the plasma particles on the inside push back.

1:05:23 What's really interesting is you have an equation for magnetic pressure,

1:05:26 which is B squared over 2μ0.

1:05:29 The magnetic field squared is the external magnetic pressure.

1:05:33 Any magnetic field anywhere generates this pressure.

1:05:37 But the plasma particles themselves also have a pressure.

1:05:40 This is the ideal gas law, and we use the definition NKT:

1:05:46 density, Boltzmann constant, and temperature for pressure.

1:05:49 And in high beta, they're the same.

1:05:52 B squared over two mu naught is NKT.

1:05:55 So for a known magnetic field,

1:05:56 I know the density and temperature of the plasma is.

1:05:59 Just to circle back to it, when we talked about fusion,

1:06:02 we talked about it having to be hot enough and dense enough.

1:06:07 And that's N and that's T.

1:06:08 So now I have a very clear equation between

1:06:11 magnetic field and density and temperature of the fusion fuel,

1:06:15 and that's really critical.

1:06:17 All plasmas have some— all fusion plasmas have some beta, some number.

1:06:22 The FRC has one of the highest betas, beta equal one.

1:06:26 However, what you also learn in school when you learn about beta the first time,

1:06:30 is you learn that high-beta plasmas are typically unstable.

1:06:34 And so the good way to think about

1:06:37 this is a tokamak is an accelerator that is stable,

1:06:41 because those plasmas that are going around in the donut,

1:06:45 there's a force on that donut.

1:06:47 But that plasma donut is very well held by all those magnetic fields,

1:06:51 by all those magnetic coils.

1:06:52 If it tried to move, it would be confined by that magnetic coil.

1:06:56 But in an FRC, it's unconfined.

1:06:58 So the plasma is confined,

1:07:00 but the whole topology can do something that is called tilt,

1:07:03 is that this whole plasma donut,

1:07:06 because it's under pressure, can just turn over.

1:07:09 The way I think about this is, think about a motor is a good example.

1:07:16 An armature in the center of your motor, you have a spinning armature.

1:07:20 You have this spinning magnet on the inside,

1:07:24 and it is held by the main axis of the magnet.

1:07:28 It can't go anywhere.

1:07:29 We don't have that axis.

1:07:30 We don't have any mechanical things inside these fusion systems.

1:07:33 They're 100 million degrees.

1:07:34 You can't put any mechanical things inside them,

1:07:37 and so we have nothing to hold onto it, and so it's unstable.

1:07:40 So when you learn about the FRC, that's the first thing you learn,

1:07:43 and it took us a number of years to learn

1:07:46 about a parameter of how to make them stable, and that's pretty fundamental,

1:07:51 but most people who've heard of an FRC haven't understood this really key fact.

1:07:57 So we have a parameter we call S star over E.

1:08:01 And we're getting really into the physics weeds here, but- Let's go.

1:08:06 it's really important, and the good analogy here is a top.

1:08:10 Literally a top, a spinning top, and so you have a top spinning on your desk.

1:08:14 You know that it'll spin for a little while and then it will fall over.

1:08:17 It is unstable.

1:08:18 However, if you spin it fast enough,

1:08:20 if you take a top and you spin it fast enough with enough angular momentum,

1:08:25 enough angular inertia into that system,

1:08:27 it'll stay upright even though it wants to just fall over,

1:08:32 even though it's unstable.

1:08:33 And we do the same thing in an FRC, is if you can drive it fast enough,

1:08:37 if you can add enough kinetic energy and inertia to the particles,

1:08:42 it will stay stable.

1:08:44 However, you can do another really key thing.

1:08:47 We are not limited now to having a very skinny top.

1:08:51 We can actually make it much bigger.

1:08:53 So the good analogy here is if you have

1:08:55 a coin and you know you're spinning that coin,

1:08:57 if you spin it faster and faster, it'll stay spinning longer.

1:09:00 However, eventually it'll slow down and fall over.

1:09:03 But if you had a roll of duct tape,

1:09:05 if you had something thicker and heavier and longer,

1:09:08 and it's spinning around that same axis, it'll stay spinning even longer,

1:09:12 both because of the inertia and because of the geometry.

1:09:15 So we have this parameter called S star over E.

1:09:18 S star is the hybrid kinetic parameter which tells you

1:09:23 how stable it is from that top point of view,

1:09:27 and the E, which is the elongation of how long it is.

1:09:31 Maybe fortuitously, thank you nature, gave us a win here,

1:09:34 which is that how we make these in these long solenoids is naturally very,

1:09:37 very these long solenoids is naturally very, very long.

1:09:41 And so we can build these with a very long lengths,

1:09:45 and if we can drive them fast enough and hard

1:09:48 enough and drive the ions to move at very high velocities,

1:09:52 we can stabilize against those instabilities and hold them stable.

1:09:56 And so we now know we can design with a given S star over E parameter,

1:10:01 we can design these for very long lives.

1:10:03 The theory of the systems we make say

1:10:06 that they should last for a few microseconds at most.

1:10:11 Us and others in the field have been

1:10:13 able to make them last for thousands of microseconds,

1:10:15 thousands of times what the stability criteria,

1:10:19 the basic criteria would tell you.

1:10:21 And so we know now how to do this, and so

1:10:23 we just design them with this built into them.

1:10:26 Can you explain a little bit more of the S star over E?

1:10:29 Are you given that, or is that an emergent thing?

1:10:33 So like at which stage, is that the result or the requirement?

1:10:39 It's a great question.

1:10:40 So it is a requirement of the system,

1:10:43 is that you must design it with this parameter in mind.

1:10:47 Got it.

1:10:48 The hard part is you have to design it

1:10:50 with S star over E being satisfied the whole time.

1:10:54 Right.

1:10:55 And here's the extra trick here.

1:10:58 S star over E is also a measure of temperature.

1:11:02 Oh boy.

1:11:03 And, and, and, yup, we're, this, it all comes back to temperature.

1:11:06 The hotter you make them is the same thing,

1:11:09 temperature as kinetic energy, is the faster you're spinning.

1:11:13 So if you take your top and you spin it faster, it's more stable.

1:11:16 But you gotta make it hot, and so here's the trick.

1:11:20 How do you make something hot that's starting cold?

1:11:22 And it has to be hot by definition,

1:11:24 and so that's part of the challenge of what we do day-to-day,

1:11:29 is getting to these hot plasmas, and where people have,

1:11:32 other people have tried to make FRCs and not been very successful,

1:11:36 is because they couldn't get it hot enough fast enough,

1:11:38 is it fell over, it tilted, before it got hot.

1:11:41 And so we spend a lot of our electrical engineering...

1:11:44 In some ways, Helion is more of an electrical engineering company

1:11:47 than a fusion company some days focusing on how to make

1:11:52 the electronics fast enough to be able to get it hot

1:11:55 enough soon enough that you can keep it stable the whole time.

1:12:00 So you're trying to reach 100 million degrees.

1:12:01 How do you get to that temperature fast?

1:12:03 And by the way, what can you say to help

1:12:08 somebody like me understand what 100 million degrees is like?

1:12:12 It seems insane.

1:12:13 What does that world look like?

1:12:15 I guess just everything is moving really fast.

1:12:18 Like you said, you can't put anything mechanical in there.

1:12:22 Yeah, so a couple of key things happened.

1:12:24 So when gas is that hot, there's...

1:12:26 We talk about the states of matter.

1:12:28 You have solids, where ice, it's cold.

1:12:31 The atoms are now bound in a lattice structure together.

1:12:36 They're held together.

1:12:37 And then liquid, you've broken a lot of that lattice structure.

1:12:39 They can move around.

1:12:40 They have some kinetic energy,

1:12:41 but they're still pretty contained, they stay in the bowl.

1:12:44 Keep heating it, now you're in gas.

1:12:47 And now these particles are free to move around.

1:12:49 They're bouncing off of each other all the time,

1:12:52 and you can keep heating it from there,

1:12:54 and that's where we talk about some more phases of matter.

1:12:57 We can add a little bit more physics here.

1:13:00 We talk about rarefied gases.

1:13:02 When we think about most gases that humans interact with, they act like a fluid.

1:13:07 And what I mean by that is that they're colliding

1:13:09 with each other so often that the particles at any one place,

1:13:12 here the air is roughly the same temperature here

1:13:15 the air is roughly the same temperature as the air here.

1:13:18 These particles are bouncing off of each other

1:13:20 as if you've put a really hot one right here,

1:13:22 it would then cool enough that all the air is roughly on the same temperature.

1:13:25 But you can be what is called rarefied, and this is like space.

1:13:28 This is where now you have particles moving around,

1:13:31 but they don't collide with each other very often.

1:13:34 And so you can have one very,

1:13:36 very high energy particle and very cold energy particle,

1:13:38 and they may not even touch each other,

1:13:40 but maybe occasionally they bang into each other,

1:13:42 they collide, and then they transfer energy.

1:13:44 That's where we call rarefied.

1:13:45 And then you can go even hotter than

1:13:47 that, and that's where now the actual atomic states, which has the nucleus,

1:13:51 which is a proton and a neutron, and an electron gets so hot,

1:13:55 that electron gets energized and then escapes, leaves the system.

1:13:58 And now they're charged.

1:13:59 You have a positive nucleus and a negative electron floating out,

1:14:03 and that happens on the order of 10,000 degrees.

1:14:08 So way hotter than what we're used to.

1:14:10 But now, we're gonna go hotter.

1:14:12 We're gonna take this plasma and go even hotter.

1:14:13 What does that mean?

1:14:14 At that point, a lot of the way we think about temperature doesn't really apply.

1:14:17 The idea that you have these random motion of particles,

1:14:20 because now they're all individual particles moving at very high velocities.

1:14:24 So there really is a measurement of its velocity.

1:14:26 So there really is a measurement of its velocity.

1:14:31 It's really a measurement of how fast is that particle moving.

1:14:35 And that's how I really think about

1:14:38 temperature when you get to that 100,000,000 degrees.

1:14:41 And so it does some more complex things.

1:14:44 If you have this high energy particle...

1:14:46 This is why we like fusion.

1:14:47 It's moving at a high velocity and there's another one moving at high velocity.

1:14:51 They will come together, they will collide, and they will fuse.

1:14:54 But other things will happen.

1:14:55 You don't want to touch that high-velocity particle with any kind of material,

1:14:59 'cause it will collide with that material, damage that material and usually,

1:15:02 like, blow off some chunks of that material.

1:15:04 So we don't do that.

1:15:06 We keep those charged particles in a magnetic field.

1:15:08 So they just bounce around and they don't ever touch anything.

1:15:12 That's really important.

1:15:13 And so it's less thinking about it

1:15:14 from the way we normally think about hot and cold,

1:15:17 and more thinking about it from a velocity point of view.

1:15:21 So what we should be imagining is extremely fast moving, what is it?

1:15:26 1,000,000 miles per hour?

1:15:28 Is that accurate?

1:15:29 That's the right kind of order for these systems.

1:15:32 Crazy.

1:15:32 So you're looking for them to collide.

1:15:34 First of all, to get back, is there some interesting insights, tricks,

1:15:39 anything you could say to the complexity of the problem

1:15:41 of getting it to that high temperature quickly?

1:15:46 So, if temperature is velocity,

1:15:49 that means they're moving quickly over a given amount of space.

1:15:52 Speed is distance divided by time.

1:15:55 And so if you have a machine of a certain size and it's moving very fast,

1:16:00 that tells you the time that that particle's

1:16:02 moving from place to place in that machine.

1:16:05 And, in fact, if it's a million miles per hour,

1:16:09 these are on the order of 100 kilometers per second,

1:16:13 which you can flip that around and you

1:16:15 can say you're moving at meters per microsecond.

1:16:18 So feet per millionth of a second.

1:16:22 And so that fundamentally tells you, and we've known this, as soon as you say,

1:16:25 "I want to do fusion," you know you need to react to the universe

1:16:29 in microseconds and be able to understand the system in that speed.

1:16:34 And if you get it hotter, it goes even faster, and you have to go faster.

1:16:38 And so we look at those and that's how we think about the systems.

1:16:42 We measure everything in microseconds, not in seconds.

1:16:44 And so when you do fusion, it's pretty wild.

1:16:47 It's literally a flash.

1:16:49 Pshh, fusion happens.

1:16:50 And it's over.

1:16:51 You start it, you do a lot of fusion, you recover energy from it,

1:16:56 and then you turn it off before the human eye can really respond even.

1:17:01 And there's a computer managing all this.

1:17:03 Like, how do you even program these kinds of systems to do the switching?

1:17:07 Is there some innovation required there?

1:17:09 So I'm continuously amazed by what the pioneers

1:17:12 in fusion were able to do before the computer existed,

1:17:15 'cause they had to control things at this scale.

1:17:17 But maybe it was pretty hard and why we've been able to be...

1:17:21 take what they did and build on it,

1:17:24 because now we use modern gigahertz-scale computing to be able to do this.

1:17:29 And so even when I started my career,

1:17:31 we talked about, like, megahertz processors.

1:17:33 Megahertz is microseconds.

1:17:35 That's great.

1:17:36 You're kind of at the border of fast enough,

1:17:39 but you can't do computation at that speed if

1:17:42 all it can do is respond in one microsecond.

1:17:45 But now gigahertz means I can do a thousand operations in that one microsecond,

1:17:50 so I can do more useful things.

1:17:52 So we use mostly...

1:17:53 This is way too fast for any human

1:17:56 to respond to, so we use what's called programmable logic.

1:17:59 So we program in sequences to the fusion system to be able to do this reversal.

1:18:05 We pre-program it and then we run a sequence and then fusion happens.

1:18:10 And so in this sequence programming language, we use a variety of them.

1:18:14 Some of the fusion codes are actually written in Fortran still.

1:18:18 Nice.

1:18:19 And though a lot is now, more and more are run in Python.

1:18:21 And so we do a lot of Python.

1:18:23 We do some Java, and then we also have because

1:18:26 of the speed of this, it's a lot of assembly language programming.

1:18:29 So we go right to the assembly level

1:18:31 of the programmable logic FPGAs and we program those.

1:18:34 And so to be able to run one of these systems,

1:18:37 we typically have a series of electrical

1:18:39 switches that turn on this electrical current.

1:18:42 Those are controlled via fiber optic because the wires are just too slow.

1:18:46 So fiber optic I can respond, I can send photons at the speed of light.

1:18:50 And so those fiber optics can respond in nanoseconds.

1:18:52 And then I trigger those fiber optics with programmable

1:18:56 logic that we programmed in the hardware assembly language.

1:19:00 As a small tangent, let me do a call to action out there.

1:19:05 I'm still looking for the best Fortran programmer in the world.

1:19:08 If people to talk to them, 'cause so many of the essential systems

1:19:12 the world runs on is still programmed in Fortran.

1:19:15 I think it's a fascinating programming language.

1:19:17 Cobol too, but Fortran even more so.

1:19:19 It's one of the great sort of computational numerical programming languages.

1:19:25 Anyway, what in terms of the sensors that are

1:19:32 giving you some kind of information about the system,

1:19:35 in terms of the diagnostics, like what kind, at this time scale...

1:19:41 ...what can you collect about the system such

1:19:44 that you can respond at the similar time scale?

1:19:49 So I'm also calling out for Fortran programmers, for different reasons.

1:19:54 Yes, great.

1:19:55 The diagnostic systems is really one of the keys to how we do this effectively,

1:20:00 because you need to be able to tell the system,

1:20:02 "We're going to trigger electrical current and we're

1:20:04 going to do it in a microsecond,

1:20:06 and we need to know if it's working right." And so in one of these FRC,

1:20:11 or these pulsed magnetic systems, you won't have just one electrical switch.

1:20:16 I've mentioned 100 mega amps, 100 million amps of electrical current.

1:20:20 Even the big transistors we use can only run at 30,000 amps,

1:20:25 so you'll end up with tens of thousands.

1:20:27 In fact, the systems we build now, tens of thousands of parallel electrical

1:20:30 switches all operating in harmony together.

1:20:32 And so you need to be able to build a system,

1:20:35 and this is what we spend a lot of time with.

1:20:37 And I made the joke that in a lot

1:20:40 of ways Helion's an electrical engineering company.

1:20:43 to be able to both program, control,

1:20:47 and then detect how they're operating, and do it all very fast.

1:20:51 So in a typical sequence, we will pre-program.

1:20:55 The operators will pre-program a sequence usually fed from a numerical

1:21:00 simulation of expecting how the fusion system will perform.

1:21:03 We start with a set of calculations.

1:21:06 We then pre-program all of these electrical switches

1:21:08 to a certain sequence to be able to inject the fuel,

1:21:11 reverse it, and then compress it up to fusion conditions.

1:21:15 And then we trigger that, and then let it go, and measure fusion happening.

1:21:22 But during that process, we have to be real time recording and measuring all

1:21:28 of the semiconductors and all of the switching in the system.

1:21:32 I'm not going to talk about measuring fusion diagnostics.

1:21:34 That's a whole other thing, which we can talk about.

1:21:36 This is just on the electrical control side.

1:21:37 And so some of the pioneering things we've been able

1:21:41 to do is that real-time you're monitoring all of these switches.

1:21:45 You're watching who is triggering correctly, who is not triggering correctly.

1:21:49 And if systems aren't working,

1:21:51 you're shutting down this because you want to make

1:21:54 sure that all the sequences are operating correctly.

1:21:56 So, some of the key diagnostics,

1:21:58 it's actually pretty amazing that even early in my career,

1:22:02 we didn't have a lot of fiber optics built into the system.

1:22:05 And now it's absolutely essential.

1:22:07 And so, every one of these electrical switches has fiber

1:22:09 optic signals going into it and fiber optic signals coming out,

1:22:13 understanding how it's actually operating.

1:22:16 And real-time, all of these systems are being monitored by more fiber optics.

1:22:22 We call these Rogowski coils, but they're electromagnetic coils that are

1:22:27 powered by the electrical current themselves.

1:22:28 So as the switches are conducting, they broadcast a signal that says, "Yes,

1:22:33 I'm electrically conducting an optical signal," fiber optics that come

1:22:36 back to a central repository where we detect those signals.

1:22:40 And so, real-time, we're monitoring all of this so that we

1:22:43 know that these systems are behaving and operating at their optimal performance.

1:22:49 What's the role of numerical simulation in all of this?

1:22:52 Sort of, I guess, ahead of time, how much numerical simulation are you doing

1:22:59 to understand how the system is going to behave,

1:23:01 how the different parameters all come together?

1:23:03 The electrical system and how that all

1:23:06 maps to the fusion that's actually generated?

1:23:12 Yeah.

1:23:12 The operation of a fusion system is pretty fascinating because all

1:23:16 of this happens on a time scale where human operators cannot be involved.

1:23:19 cannot really be involved.

1:23:22 And so, you have to have pre-programmed the majority, we call them shots.

1:23:29 You're going to do a shot, and when you're operating them repetitively

1:23:31 and you're running long periods of time, you still have all computers doing both

1:23:36 the triggering and the measuring of how they're performing,

1:23:40 real-time the whole time.

1:23:42 And so, how this typically works, at least in our systems,

1:23:47 is that we will design a system with a combination of some numerical simulation

1:23:52 tools that we've developed based off

1:23:55 of decades and decades of amazing government programs.

1:23:59 National programs developed these numerical codes.

1:24:02 We use a code called an MHD, magnetohydrodynamic code.

1:24:07 And that's, for people,

1:24:09 for the engineers out there who are used to CFD, computational fluid dynamics.

1:24:14 This is very similar where you take the same sets

1:24:17 of equations actually and add electromagnetic equations on top of those.

1:24:21 And so you get magnetohydrodynamic.

1:24:24 Are you simulating at the level of a particle?

1:24:26 Is there some quantum mechanical aspects to this also?

1:24:28 How low does it go?

1:24:30 Yeah, we have multiple codes at different levels,

1:24:32 because one of the main computational challenges is, amazingly,

1:24:36 even given all that we have been, have built, for fusion systems,

1:24:43 computers are still not fast enough to measure, to simulate everything.

1:24:47 And so, we have a number of codes that we use.

1:24:52 One we call fluid codes, where you treat the ions,

1:24:57 the electrons, all these fusion particles.

1:24:59 You treat them as as fluids,

1:25:01 as gases, ideal gas law, with electromagnetic forces.

1:25:04 In those, we can simulate not just the fusion fuel,

1:25:08 which is important, but all of the electrical circuitry.

1:25:11 We talked about capacitors and magnetic coils,

1:25:13 and the electrical current and the switches.

1:25:16 We actually simulate the full thing, starting literally with a SPICE model.

1:25:20 More of that electrical engineering.

1:25:21 We start with the SPICE model and use that to drive the plasma physics model,

1:25:26 and that's one level of simulation.

1:25:28 We use that to do design work,

1:25:30 and then also to try to understand how we think the machine will run.

1:25:33 But then we go one level deeper and we start thinking about particles,

1:25:36 and we think about the ions,

1:25:38 and we treat the ions as particles, and we look at the ion behavior.

1:25:42 For that one, the computational resources

1:25:44 are several orders of magnitude larger.

1:25:47 Luckily, a lot of the work in GPUs,

1:25:50 the AI data center work is directly applicable to those simulations.

1:25:54 It's been able to speed up our work, which is pretty fascinating.

1:25:57 That's a whole other tangent we can go down.

1:26:02 Those hybrid codes we call them,

1:26:04 particle and cell codes now treat the ions as particles,

1:26:08 and that lets us measure and simulate the behavior.

1:26:11 I mentioned the stability criteria, S star over E, the top behavior.

1:26:14 That behavior, we now need these more advanced codes to be able to simulate,

1:26:18 and those are more modern.

1:26:20 We've only been able to apply in practice for the last few years,

1:26:24 actually, which is pretty fascinating.

1:26:26 The old stability rules were built off of testing, empirical tests,

1:26:31 where now we can simulate that, and we know why they work and how they work,

1:26:35 and we can do some predictions on them.

1:26:37 And so, that's really fascinating that we've been able to push those boundaries.

1:26:40 And what are the different variables you're playing with?

1:26:42 Are you still playing with like topology?

1:26:44 Like, what are the different variables in- in play here?

1:26:47 Yeah.

1:26:47 Each of the different simulations we analyze and use

1:26:51 it to design different parts of the machine.

1:26:53 So, at the MHD level where we have the SPICE,

1:26:57 where we actually have the circuit model,

1:26:59 our design team uses this to design the circuitry,

1:27:02 where we're designing which capacitor to use, which switch to use,

1:27:06 how many cables to use, literally to that level, how big of a cable to use.

1:27:10 So as we're doing power plant designs right now,

1:27:13 those are the tools we're using today, every day, the team is using.

1:27:17 Then you can go one level deeper and say, "Okay,

1:27:20 let's use these more advanced computational tools about stability to say,

1:27:24 "Okay, great, but I now know the circuitry,

1:27:27 but let's look at the magnetic field topology.

1:27:29 How do I design the magnet,

1:27:31 the shape of the magnet exactly, the timing of the magnet exactly?

1:27:35 I have to trigger one magnet, and the next magnet next to it,

1:27:38 and the next magnet next to it.

1:27:40 How do I have that shape and that design?"

1:27:43 And so that's where you're using those more advanced tools.

1:27:45 Now, those unfortunately, those are still too slow.

1:27:49 And so, those simulations may take a day or two to run.

1:27:53 And so, an operator right now does a lot of simulations ahead of time,

1:27:58 then collects data through their operations of the machines,

1:28:02 making these field-reversed configurations, going through parameter sweeps.

1:28:05 And then the simulation team then goes back

1:28:08 and looks at that data and compares it with simulations.

1:28:11 I'm really excited about some of the things we're seeing in artificial

1:28:14 intelligence and reinforced learning to be able to speed up that process.

1:28:19 So we're watching and starting to work on that now: can we now,

1:28:23 rather than using it where we use it today,

1:28:26 where we do a simulation to design a machine or a test,

1:28:30 run the test, and then over the next

1:28:32 couple of days compare the testing with the simulation

1:28:35 and use that to inform what we're going to run for the next set of tests.

1:28:38 But in fact, do it more real-time,

1:28:41 where an operator can pull up what the AI or what

1:28:44 the machine learning would have predicted it should have done.

1:28:47 And then use that to understand what's happening in the actual programs,

1:28:52 in the actual generators themselves.

1:28:54 All right.

1:28:54 So there's a million questions there.

1:28:56 So first of all, how much understanding

1:28:58 do we have about how many collisions happen?

1:29:01 Can we go to the fusion?

1:29:04 How many collisions are there and how does that map to the electricity?

1:29:09 And maybe can you just even speak to the directly mapping to the electricity,

1:29:14 which is one of the differences between this approach and the tokamak approach?

1:29:20 So how much fusion do you get out from these systems?

1:29:22 And that's really the right key question.

1:29:25 So we already talked about beta, that B squared, the magnetic pressure,

1:29:30 is equal to NKT, N being the density, T being temperature.

1:29:35 And then we talked about fusion,

1:29:38 where your goal for fusion is to get particles hot,

1:29:41 high temperature, get enough of them together, density.

1:29:45 And then you want to get them together long enough.

1:29:48 We call that tau.

1:29:50 So N, T, and tau, long enough that fusion happens, and a lot of fusion happens,

1:29:55 more than any of the loss rates that are happening, NTT.

1:29:58 And in beta with B squared,

1:30:00 you know already two of those parameters, NNT, are equal.

1:30:04 And so that tells you right away the goal is to maximize magnetic field,

1:30:08 absolutely maximize magnetic field.

1:30:10 And most folks in magnetic fusion,

1:30:12 whether it's a tokamak or it's Theta Pinch or it's an FRC,

1:30:15 are attempting to do that, maximize the magnetic field.

1:30:18 So we're all pushing to that.

1:30:19 What's really nice in pulse systems is that we know how to do that.

1:30:24 In fact, In a pulse system,

1:30:28 researchers in pulsed magnetic fields have demonstrated

1:30:30 over 100 tesla magnetic fields in pulsed magnets.

1:30:34 That's much higher than you can get in a steady magnet,

1:30:38 or what's been demonstrated so far.

1:30:41 Just a clarification question.

1:30:43 So maximizing magnetic field is about the N and the T, the beta?

1:30:47 So we're not talking about tau yet.

1:30:49 Not yet, but we need to, because that's really important.

1:30:53 We can even talk a little bit further about how fusion scales.

1:30:56 And so in fusion, the hotter you get the fuel, the more fusion you get.

1:31:01 And we know that by increasing the magnetic field,

1:31:05 B squared as NT, you increase density and temperature together.

1:31:09 More density, more temperature is more fusion,

1:31:10 plus more temperature is even more fusion.

1:31:12 And so what we see is that in our, in these types of systems,

1:31:17 a scaling very clearly of magnetic field to the 3.75 power,

1:31:22 or even in a lot of demonstrations, 3.77.

1:31:26 That specific scaling.

1:31:29 That's a very strong scaling of fusion power output, and fusion reactions.

1:31:33 And so that tells you you want to go to a maximum magnetic field as you can.

1:31:38 Pulsed systems are really powerful.

1:31:40 Pulsed systems have showed when you do pulsed

1:31:42 magnetic fields compared to a steady magnetic field,

1:31:44 researchers have shown over 100 Tesla magnetic fields.

1:31:48 Where in a steady system,

1:31:50 people have showed in the 20, maybe high 20 Tesla systems.

1:31:53 And if it's B to the 3.77 power,

1:31:56 already you can see massive fusion power outputs by doing a pulsed system.

1:32:02 Okay, got it.

1:32:03 So we're maximizing the magnetic field.

1:32:05 So that's going number go up, super up.

1:32:08 How do you get the duration, the tau?

1:32:11 But then I said pulsed, and pulsed already implies shorter tau.

1:32:15 Yes.

1:32:15 And so that is in the fusion field the name of the game.

1:32:19 Folks will have a very inertial fusion.

1:32:23 We'll have a nanosecond tau.

1:32:25 Very short, but then very high pressure.

1:32:27 They don't have magnetic fields, but very high pressure.

1:32:30 And then in stellarators and Tokamaks, your goal is very long tau,

1:32:36 but you'll have much lower density and you

1:32:39 can't really go too much in temperature, but they'll have much lower density.

1:32:43 And so where we live in the pulsed magnetic,

1:32:46 or the magneto-inertial fusion is in the middle,

1:32:49 is in extremely high magnetic fields, increasing pressure as much as you can,

1:32:53 and then keeping them around long enough.

1:32:56 And so that gets to the tau.

1:32:58 That gets to that energy confinement lifetime, and also, it gets to stability.

1:33:02 And so this is the thing that this field-reversed configuration,

1:33:06 which has showed that we can build.

1:33:09 These plasmas can last for hundreds or thousands of times the basic

1:33:15 theory has shown that now you can have long enough lifetimes.

1:33:19 So what that means is in a practical fusion system that there are

1:33:23 lifetimes of these high beta pulse systems

1:33:26 between 100 microseconds and a few milliseconds, thousandths of a second.

1:33:30 And you hold onto it for a few thousandths of a second.

1:33:33 You do fusion, and then you exhaust it.

1:33:37 And so the whole process in this is we

1:33:40 start with a magnetic field that fills the full chamber.

1:33:46 You then inject fusion fuel.

1:33:49 You ionize it, superheating it now to a nice, cold one million degrees.

1:33:54 But hot enough that you have charged particles.

1:33:57 You have plasmas.

1:34:00 You can then start increasing the magnetic field.

1:34:03 You form a field-reversed configuration,

1:34:05 and then rapidly increase the magnetic field further.

1:34:09 Increasing from one to five to 10, 20, to even higher magnetic fields.

1:34:16 And as you do that, the plasma heats.

1:34:19 You compress it, increasing the field and pressure.

1:34:23 Fusion is now happening.

1:34:25 New charged particles are being born inside this system

1:34:28 with a tremendous amount of heat and energy.

1:34:31 but in charged particles.

1:34:33 This is where the beta really, really works to your advantage,

1:34:39 is that just like magnetic pressure on the outside,

1:34:44 magnetic pressure is NKT compresses compresses

1:34:48 the fuel in increasing pressure and temperature.

1:34:50 When the pressure and temperature of the plasma increase, NKT increases.

1:34:55 It pushes back on the magnetic field,

1:34:58 increasing the magnetic field on the outside of the plasma,

1:35:01 and what that does is magnetic field is electromagnetic current,

1:35:05 and current running in a wire.

1:35:07 And what that does is pushes current back in the wire.

1:35:10 So the plasma itself now pushes back on the magnetic field,

1:35:14 pushing electrical current out of the system and recharging

1:35:17 the capacitors where we started this whole process.

1:35:21 all in a self-organizing way.

1:35:23 So I think it's good to sort of clarify how fusion usually generates energy,

1:35:28 where this intermediate step of heating up water,

1:35:31 then the steam is the thing that leads to electricity.

1:35:35 And then, of course, the FRC method that you use leads directly to electricity.

1:35:39 I was wondering if you could describe the difference between those two.

1:35:44 Yeah.

1:35:45 I like the analogy of the match and the campfire,

1:35:49 and I hear that a lot in fusion.

1:35:52 Where a lot of what steady fusion, think a stellarator or a Tokamak,

1:35:57 is attempting to do is take a little bit of fuel, that match,

1:36:01 and then add heat to ignite that match,

1:36:05 and then put it with enough fuel and in the right conditions

1:36:09 and hold onto it for a long time that it grows into a campfire.

1:36:13 Even if they do a good job, a bonfire.

1:36:15 It's creating a tremendous amount of energy in that steady system.

1:36:19 Burning fuel in the same place, generating some ash,

1:36:23 generating a lot of heat in that reaction.

1:36:26 And in a traditional, in a Tokamak or a stellarator,

1:36:29 that's a lot of what you're doing,

1:36:31 is you're holding onto the heat as much as possible to keep that reaction going.

1:36:37 And the optimal fuel is called deuterium and tritium, where you have...

1:36:42 Deuterium is a heavy isotope of hydrogen where you have an extra neutron,

1:36:46 and tritium is a very rare form of hydrogen that's an unstable form.

1:36:51 It's so rare it's hard to get.

1:36:53 Where it has two neutrons and a proton,

1:36:55 and when you fuse those together at very high temperatures at very

1:37:01 high densities or high enough densities

1:37:03 and very high temperatures they make helium,

1:37:06 which is a charged particle, which stays inside the campfire,

1:37:10 inside the Tokamak continuing to heat it and stoke the flames,

1:37:15 and it makes a neutron which leaves the system because it's uncharged.

1:37:19 It has no charge, and in that system, it's actually ideal.

1:37:22 It's really great because in a campfire,

1:37:24 you have this reaction going and you want to get the energy out of it.

1:37:28 You wanna use it, and you don't want

1:37:29 to just burn up all the fuel and do nothing.

1:37:31 That's not really valuable.

1:37:32 What's really valuable is to stand next to the campfire and get the heat,

1:37:36 get what comes off of it.

1:37:38 And then use that in a traditional fusion system to...

1:37:42 boil water, to heat the water, and then at 30, 35% efficiency,

1:37:46 then convert that through a steam turbine into a cooling tower,

1:37:50 and cool off the fuel and extract electricity.

1:37:53 And we know steam turbines.

1:37:55 Coal plants do this.

1:37:57 Nuclear fission reactors do this.

1:37:58 And so we know how to do that, and that's the traditional way of doing it.

1:38:04 But I think there are other ways to do it with a pulsed magnetic system.

1:38:09 There's one more thing you get to do because you have this high beta

1:38:16 where there's an electric field and an electromagnetic

1:38:19 force that's now compressing the fusion fuel.

1:38:22 It's increasing in temperature.

1:38:23 It's getting hotter.

1:38:24 It's increasing in temperature.

1:38:26 Density fusion is happening.

1:38:27 New fusion particles are being born,

1:38:29 and those particles are not just stoking the flame.

1:38:32 They're not just holding onto the campfire like in the Tokamak,

1:38:35 but they're doing another thing which is really powerful,

1:38:37 which is they're pushing back on the magnetic field.

1:38:39 They're applying a pressure.

1:38:41 That pressure induces a current.

1:38:42 We can extract that electrical current.

1:38:45 But it takes you into another direction,

1:38:47 so your analogy of the campfire now breaks down,

1:38:49 because now the campfire is expanding.

1:38:51 It's pushing back on something,

1:38:53 and so now it's the analogy of the piston engine.

1:38:56 As you move from the match, the campfire, to now pistons.

1:39:00 And so, in a piston engine, you use the motion of the piston,

1:39:03 the pressure on it and the motion of it to do something useful,

1:39:07 and in a piston engine,

1:39:08 it's to turn a crankshaft and turn a crankshaft and run a...

1:39:13 Run wheels, or maybe even a piston engine to turn

1:39:18 a crankshaft and run a generator and make electricity.

1:39:21 And in fact, you can do it pretty high efficiency.

1:39:24 and a generator using that method, using the expansion of that piston,

1:39:29 and what we do is use the expansion

1:39:31 of the magnetic field to extract that electricity,

1:39:33 and we believe you can do it at much, much higher efficiencies.

1:39:37 In fact, there have been theoretical papers that show not 30

1:39:41 to 35% efficiency like a steam turbine can do, but 80% efficiency.

1:39:46 85% efficiency, extracting much more of the energy of the fuel in that process.

1:39:53 Can you actually just take a tiny tangent...

1:39:55 On the word efficiency here?

1:39:57 So, yeah, so you said 30%, so it's inefficient,

1:40:01 and that efficiency measure is how much

1:40:03 of the energy is actually converted to electricity?

1:40:07 That measure is how much of the thermal energy

1:40:09 that gets outside of the system is then converted into electricity,

1:40:13 which is the thing we care about.

1:40:14 We want...

1:40:15 we're not in this to make fusion.

1:40:17 We're in this to make electricity.

1:40:19 And we're using fusion to make electricity, and so from my point of view,

1:40:23 that should be the focus: how do we get to that?

1:40:25 So that's the efficiency of that thermal

1:40:27 energy that makes it out to electricity.

1:40:30 What it is not a measure of how much energy you put into the system

1:40:33 and what happens to that in terms of you started this campfire with a blowtorch.

1:40:38 What about all that blowtorch energy?

1:40:40 What are you getting for that?

1:40:42 And so I think that's something that high beta is one more side

1:40:47 benefit that it turns out is actually maybe the tail that wags the dog,

1:40:51 is that not only do you at high efficiency get out any of the new fusion energy,

1:40:55 which is great, because that's what you want, make electricity from fusion,

1:40:58 but you also get to recover all of that magnetic energy you put back into it.

1:41:02 And that's the really powerful one,

1:41:04 and that's something that folks have demonstrated over 95% efficiency,

1:41:08 that you can put electricity into fusion and then

1:41:12 get that electricity back out at 95% efficiency,

1:41:15 plus some very high efficiency, maybe 80%,

1:41:18 maybe higher of all the fusion product electricity too.

1:41:21 So now you're making a tremendous amount of electricity in one of these systems,

1:41:25 and that has all kinds of performance

1:41:28 and engineering benefits that are really powerful,

1:41:30 but it also pushes you to other fuels.

1:41:34 So we talked about how deuterium and tritium fuels make this neutron,

1:41:38 which leaves the system to boil water,

1:41:40 to run steam turbines, but it doesn't push back on the magnetic field.

1:41:44 So in one of these high beta systems, it's actually not a great fuel at all,

1:41:48 and so the other fuels that are out there are even more interesting,

1:41:53 and one of the candidate fuels that's

1:41:55 really interesting is called deuterium and helium-3.

1:41:58 And we talked about deuterium, heavy hydrogen.

1:42:01 Well, helium-3, the nucleus is also called a helion.

1:42:03 That's why we named the company that.

1:42:05 is light helium, which is...

1:42:08 In normal helium, which is what you find in a balloon,

1:42:11 there's two protons, two neutrons.

1:42:13 It's very stable and found commonly.

1:42:17 Helium-3 is also stable, but it's not found commonly.

1:42:23 Fortunately, it's lightweight, so it leaves.

1:42:25 It literally leaves the atmosphere and goes into space.

1:42:27 So we don't have a lot of it here on Earth, and so you have to make it,

1:42:31 or you have to go into space,

1:42:33 and there's a whole other thing about where do you get it?

1:42:35 Do you get it from the moon?

1:42:36 Jupiter has, it turns out, massive amounts of helium-3.

1:42:39 But when you take deuterium and helium-3 and you fuse those together,

1:42:44 you also get that helium particle,

1:42:46 that alpha particle, what we call that in fusion.

1:42:49 But instead of the neutron, you get a proton,

1:42:52 and that proton is a charged particle.

1:42:55 It's a hydrogen nucleus.

1:42:56 That proton is now trapped in the magnetic field,

1:42:59 pushes back, and you can extract that electricity.

1:43:01 Now, there are some prices to be paid for this helium-3 fuel.

1:43:03 But for a high beta system for this helium-3 fuel.

1:43:06 But for a high beta system like a pulsed magnetic fusion system,

1:43:10 that's really the ideal fuel.

1:43:12 like a pulsed magnetic fusion system, that's really the ideal fuel.

1:43:14 When you say prices, what are the prices?

1:43:16 What shape do the prices take?

1:43:18 What, what are the prices?

1:43:19 What shape do the prices take?

1:43:22 prices take?

1:43:23 All kinds of shapes: physics, engineering, technical, and business costs.

1:43:28 And so, let's dive in.

1:43:32 So, we talked about how helium-3 is...

1:43:34 From the fusion physics point of view,

1:43:36 from the fusion physics point of view, we talked about 100 million degrees.

1:43:39 That's the temperature that deuterium and tritium fusion works really well.

1:43:42 And that's the temperature fusion works really well.

1:43:44 And that's the temperature that traditional fusion folks have really

1:43:46 focused that traditional fusion folks have really focused on getting to.

1:43:49 That's the threshold.

1:43:50 When you get to 100 million degrees, you're at the operating point of fusion,

1:43:53 and you know it works, colloquially anyway.

1:43:54 of fusion, and you know it works, colloquially anyway.

1:43:58 Helium-3 requires higher temperatures.

1:44:00 That's not enough.

1:44:01 Fusion happens That's not enough.

1:44:03 Fusion happens for deuterium and helium-3 at 100 million degrees,

1:44:06 degrees, but it's not its optimal temperature.

1:44:07 And in fact, in a high beta system,

1:44:09 the optimal the optimal temperature is higher:

1:44:11 200, even sometimes 300 million degrees.

1:44:13 So you have to get to even higher temperatures.

1:44:15 Temperature's hard, and so you have to push Temperature's hard,

1:44:17 and so you have to push to even higher temperatures than you had before.

1:44:21 And so that's one of the downsides.

1:44:22 The other downside can be, as you get to those The other downside can be,

1:44:26 as you get to those higher temperatures, we talked about B squared is NT.

1:44:30 B squared is density times temperature.

1:44:32 is density times temperature.

1:44:33 Well, for a given magnetic field, density and temperature are now inverse.

1:44:36 field, density and temperature are now inverse.

1:44:38 So as I increase temperature, density decreases.

1:44:40 So as I increase temperature, density decreases.

1:44:42 And so now you have an issue An issue

1:44:44 of you may have less particles to do fusion,

1:44:46 which means your fusion system to do fusion,

1:44:48 which means your fusion system has to get bigger than it was before.

1:44:52 So for the same reaction rates, a helium-3 system compared to deuterium-tritium,

1:44:57 has to operate at a higher temperature and be bigger.

1:45:01 However, the flip side is if you can now recover energy at 80,

1:45:05 recover energy at 80, at three times the energy efficiency,

1:45:08 at 80 some percent at 80 some percent versus 30 some percent,

1:45:12 and recover all your input energy, then now it's actually about the same size.

1:45:17 Because they're the same electricity output, not energy.

1:45:19 It's not energy that we're worried about.

1:45:20 It's electricity we're worried about.

1:45:22 Electricity output, now you can actually actually

1:45:25 build systems of similar size and similar energy.

1:45:26 Only they're now at this much higher efficiency.

1:45:28 Only they're now at this much higher efficiency.

1:45:31 Got it.

1:45:31 Can you say more about size?

1:45:33 What are we talking about here?

1:45:35 Why is size an important constraint?

1:45:37 And that gets to one of the other prices.

1:45:39 That gets to money.

1:45:40 Our goal is we want to build clean,

1:45:42 low-cost electricity and get it out in the world.

1:45:44 low-cost electricity and get it out in the world,

1:45:46 but that means it needs to be low-cost.

1:45:48 That's fundamental.

1:45:49 If it's really expensive, no one's going to buy it.

1:45:52 And, while it can be clean, it's not going to be deployed.

1:45:55 And so that is always has to be a part of why,

1:45:59 what the promise of fusion is that can be low cost.

1:46:03 So how do we know how much fusion systems cost?

1:46:07 That's a really great question.

1:46:09 And a lot of it comes down to fundamental size,

1:46:13 that you have to just build things.

1:46:15 And so there's some really first principles,

1:46:17 cost engineering you can do around power

1:46:20 plants for fundamentally what do they cost?

1:46:22 How much concrete went into it?

1:46:24 Fundamentally, how big is it?

1:46:26 And that, and that if you're doing a good job of manufacturing, you are,

1:46:32 your goal is to manufacture a product for as low of cost as you

1:46:37 can so you can sell it for as low price as you can.

1:46:40 It asymptotes to the material cost.

1:46:43 Ah.

1:46:44 Because you never get cheaper than that.

1:46:45 So this literally, in some sense, some sort of first principle sense is how much

1:46:51 concrete-- How- how-- ...goes into building the power plant.

1:46:55 How much concrete, how much steel, how much, copper and aluminum.

1:47:00 Different materials cost different amounts, but at the end of the day,

1:47:04 the cheapest function is the least amount of materials.

1:47:07 Wow.

1:47:07 Okay.

1:47:08 And so that's, we think a lot about that and how we

1:47:11 can make these systems smaller so they can be developed at lower cost.

1:47:14 Now, there's a flip side.

1:47:15 You still need to produce electricity.

1:47:17 So if you make them really small and they don't produce electricity,

1:47:19 and there is some minimum size to fusion, and that's really important.

1:47:23 Fusion scientists and engineers don't see you'd ever have

1:47:26 a fusion generator on the back of your DeLorean, for instance.

1:47:30 The physics doesn't let that one happen,

1:47:32 at least physics as we've understood for the last, you know, 100 or 200 years.

1:47:38 Well, there's a lot of really interesting business questions here,

1:47:41 because you're basically at the cutting edge of science,

1:47:45 of technology, of physics,

1:47:47 of engineering trying to basically innovate into the future rapidly.

1:47:53 How do you how do you do that?

1:47:57 Because the R&D here, the research alone is a lot of money.

1:48:01 So what's, I mean, what can you say about that?

1:48:04 How to be bold and fearless in pushing this technology into the future when

1:48:08 so much is unknown and it costs so much to just do the research?

1:48:15 So I think about this in a couple of ways.

1:48:20 One, the need.

1:48:21 We look to the world and we know the world needs clean,

1:48:29 low-cost, safe electricity.

1:48:31 And just to meet our needs today,

1:48:37 and not to even talk about the needs of tomorrow

1:48:39 or the needs of AI or any of the growth that's probably coming.

1:48:44 Just to meet today.

1:48:46 And so, but fundamental to that is it has to be a product that people will buy.

1:48:51 It has to be a generator that is making that electricity at low cost.

1:48:55 And it's got to be soon.

1:48:58 And so a lot of what I think about is how do we do those two things together?

1:49:03 And a lot of that is scale, and a lot of that is thinking about...

1:49:08 And not big scale.

1:49:09 In fact, it's the opposite of that.

1:49:11 It's small scale.

1:49:12 It's how do you build a product that's mass producible,

1:49:14 that you can build quickly and learn quickly?

1:49:18 And what I've found in my career

1:49:21 at this is that they're actually the same thing.

1:49:25 And that the faster you can build a thing,

1:49:28 the faster you can learn if that thing works,

1:49:31 the faster you can now you can actually

1:49:34 iterate on that and build the next thing.

1:49:37 And so what I have spent my career building

1:49:41 is teams of humans and a company that are builders,

1:49:46 that can build high technology things quickly.

1:49:49 That if you want to do R&D,

1:49:52 you don't want large scale, multinational, complex, huge systems.

1:49:57 You want to actually take the smallest

1:49:59 thing you can build that accomplishes the mission,

1:50:02 and in fusion, there is a minimum size, but accomplishes the mission,

1:50:05 and then build it quickly and build whole teams around building

1:50:08 it quickly and incentivize folks to move quickly, iterate and learn.

1:50:13 And the irony I think of one of the things

1:50:17 that I've discovered is that by focusing on manufacturing,

1:50:20 by focusing on low cost,

1:50:23 very rapid manufacturing, you actually get to do science faster,

1:50:26 and at the beginning of my career, I would never have guessed that.

1:50:30 I would have thought the way to do science

1:50:32 is to make a giant demonstration particle accelerator somewhere.

1:50:36 Like to make a large complex science experiment is the best way to do science.

1:50:43 And what I've found is actually small iterative,

1:50:45 just building as fast as possible gets you there faster,

1:50:50 because you can learn, you can build, you can iterate.

1:50:52 You can solve the problems, and then you can learn the fundamental physics,

1:50:57 learn the scaling, learn the FRC,

1:51:00 and the B to the 3.77 power and learn those things way sooner than if you

1:51:06 would have just started on one mega project

1:51:08 and then waited decades to get to the answer.

1:51:11 There's a profound truth in that, something

1:51:14 about the constraints of pushing for the simple,

1:51:17 for the low cost, for the manufacturable.

1:51:19 That pushes everything, pushes the science, pushes the innovation.

1:51:22 In fact, you should maybe explain that you're,

1:51:25 I believe, on the seventh prototype.

1:51:27 This is insane.

1:51:29 The rate of innovation here is insane.

1:51:32 Can you maybe speak to all the different prototypes you went through,

1:51:36 what it took to just iterate rapidly?

1:51:39 And maybe it would be really interesting for people,

1:51:42 like what can you say about the teams that's required to make that happen?

1:51:47 Like what kind of people are required to make that happen at that fast rate?

1:51:52 And we're not talking about, like, software here.

1:51:55 We're talking about everything, the full stack.

1:51:58 All the way down to the physics at 100 million degrees.

1:52:05 At speeds of one million miles per hour.

1:52:07 It's insane.

1:52:07 Anyway, so what, How do you iterate the prototypes,

1:52:10 and what kind of teams make it happen?

1:52:13 So at Helion, we've- we've built seven systems.

1:52:17 The first six were a series of prototypes that we built end to end

1:52:23 that were focused on scaling the process

1:52:26 of making these field- reverse configurations,

1:52:29 compressing them to thermonuclear fusion conditions,

1:52:33 and demonstrating that you can do fusion and then increasing the scale,

1:52:36 increasing the temperature and the energy.

1:52:39 The very first ones were named after beer.

1:52:41 Actually the most successful was the inductive plasmoid accelerator, the IPA.

1:52:45 And it was the first system that showed that the team could make

1:52:51 these FRCs and hold onto them and understand some of the stability criteria,

1:52:56 the heating criteria.

1:52:57 And then we started increasing the field.

1:53:00 Now, okay, great, we can hold onto one of these FRCs.

1:53:03 We know how long and how to make them,

1:53:05 but now can we squeeze on them and start doing fusion?

1:53:08 Increasing in pressure and temperature.

1:53:10 What we noticed is- is you know,

1:53:13 machine after machine, we always used Starbucks.

1:53:15 We were in Redmond at the time, Redmond, Washington,

1:53:19 and Starbucks cups sitting on top of the machine as the, this is the scale.

1:53:24 They were too small to have a human really in the picture all the time,

1:53:27 so the Starbucks cup was enough.

1:53:30 And so then we switched to Tall, Grande, venti.

1:53:34 And then the biggest, trenta, was the biggest system that came online in 2020.

1:53:41 That was a system that showed 100 million degrees

1:53:43 and was the first system that did deuterium and helium-3 fusion.

1:53:46 In fact, as far as we know,

1:53:48 the only bulk deuterium-helium-3 fusion that has been done

1:53:52 and also showed the 100-million-degree fusion temperatures from an FRC.

1:53:57 And throughout that time, the earliest work was government funded,

1:54:03 government grants, SBIRs and other type of government grants.

1:54:06 And- and actually the team involved myself and the rest

1:54:09 of the founding team were really good at winning government programs,

1:54:14 doing fundamental science, but moving very quickly.

1:54:18 And there's a lot of ways to think

1:54:19 about how to iterate and how to build quickly.

1:54:20 I want to talk about the teams first,

1:54:22 and then we can talk about some of the technology- ...uses to do that.

1:54:26 But a lot of it is thinking about if your goal is to get the product,

1:54:32 electricity out to the world as soon as possible,

1:54:35 then you should be looking at everything you do towards that lens.

1:54:39 And so that's thinking about the materials you choose.

1:54:42 You want to, at every turn, choose commonly available materials.

1:54:46 If you have to wait for supply chain for an ultra-rare material,

1:54:50 it's gonna take you a lot more time.

1:54:52 And so do everything you can to engineer

1:54:54 a system that uses simple aluminum alloys, simple copper alloys.

1:54:58 And if you have to use tungsten,

1:55:00 and maybe you have to use tungsten in some of your systems,

1:55:03 which is a hard-to-find alloy- make sure

1:55:05 you're using commonly available thicknesses of tungsten sheet.

1:55:08 You know, those kinds of engineering

1:55:10 analyses and thought processes at every step.

1:55:12 And that's how we built these systems, from IPA to Venti up to Trenta,

1:55:18 was always looking at, "How do we build systems that are

1:55:22 easy to build and mass produced?" Because this is the other

1:55:25 thing that I don't know that early in my career I'd

1:55:28 have predicted is that by making a hundred of a thing,

1:55:32 you can actually make it faster than if you go make one of a thing.

1:55:36 And that's because when you look at our fusion systems,

1:55:40 we talked about these big magnets.

1:55:42 You could build one giant big, complex,

1:55:44 hard-to-make magnet that's heavy and you have to move it around

1:55:47 with a crane and requires very complex machining by ultra-rare CNCs.

1:55:53 Or, you could then make that out of a composite of 100 smaller magnets.

1:56:00 Each of those magnets now can be made on a simple machine.

1:56:03 Each of these magnets can be picked up by a human, they're light enough.

1:56:06 They can be made and manufactured and mass produced.

1:56:09 And that's what we did.

1:56:11 And that was our whole design philosophy on these machines is,

1:56:15 at every turn, how do we go faster?

1:56:18 A classic one that still to this day I push the team on is,

1:56:25 again, thinking about how do you move fast, eBay.

1:56:29 We buy, and I don't know that I've ever said this publicly,- Oh boy, here we go.

1:56:37 This is great.

1:56:38 we spend a lot of time on eBay.

1:56:40 You've got to find a way, yeah.

1:56:42 You've got to move.

1:56:43 And here's an example.

1:56:44 We use a vacuum pump because in these systems

1:56:46 you've got to pull out all the air.

1:56:48 So we use a vacuum pump called a turbomolecular vacuum pump.

1:56:51 This is a commodity.

1:56:52 This is used in a variety of particle accelerators, scientific applications.

1:56:55 There are many of them.

1:56:57 They're robust.

1:56:57 They last a long time.

1:56:59 They also have a very small supply chain.

1:57:02 So if you want to buy a brand new turbomolecular pump, you can,

1:57:06 and you might wait nine months from the manufacturer

1:57:09 to go make one for you and deliver it for you.

1:57:11 But I can go today and get the same model that was

1:57:15 made 10 years ago and get it on eBay today, right now.

1:57:18 However, it might not work.

1:57:19 Like you don't know how well it works or how clean it is,

1:57:23 or any of those things.

1:57:25 And so what we do is, you don't go to eBay to save money.

1:57:31 It does.

1:57:32 It's cheaper, turbo pumps that are sitting in eBay right now,

1:57:36 bring those Bring those in-house, test them.

1:57:38 Maybe only one of them meets the specifications you need, but guess what?

1:57:41 You just got a pump in two weeks instead of nine months.

1:57:45 And you got it, and it's in the door,

1:57:47 and it's operational, and it's running, and you're moving.

1:57:50 See, I love this.

1:57:51 I love that kind of stuff.

1:57:53 One of the only people I've really seen do that is Elon.

1:57:56 He put together that cluster in Memphis in a matter of weeks,

1:57:59 which is nothing like that has ever been done before.

1:58:01 And this eBay way is really the kind

1:58:10 of thing that's required to make that happen, as you shortcut the supply chain.

1:58:16 And everywhere you can, you still have to deliver the working product, right?

1:58:19 Right.

1:58:19 That is, you cannot sacrifice the quality.

1:58:21 But do you really need the shiny brand-new one

1:58:25 when the used one is going to do the job?

1:58:28 And we think about that across the board.

1:58:30 Do we take the best plasma diagnostic,

1:58:33 the most sophisticated plasma diagnostic in the world that is 3%,

1:58:38 that has an accuracy of within 3%?

1:58:41 And it's going to take me three years

1:58:43 and maybe a few million dollars to go build?

1:58:46 Or do I take a technology from 10 years ago that's 5% accurate,

1:58:50 that's good enough, that I can go build in a month?

1:58:54 And the answer for us, at Helion and for the team that we've put together,

1:58:59 is that scrappy, "I want to just solve the problem.

1:59:02 I don't need necessarily the best solution,

1:59:04 but let's go make it happen." And so that's something that we routinely do.

1:59:09 I think sometimes I have challenges with my academic colleagues

1:59:12 on this, is that we have a difference of opinion.

1:59:15 Because that 3%, well, that's way better than 5%.

1:59:18 So shouldn't you do that?

1:59:19 You'll know your data better.

1:59:20 But 5% is good enough.

1:59:22 Now, 50% would not be good enough.

1:59:24 And so that technology wouldn't have been applicable.

1:59:27 And so finding that middle ground is a hard thing to do,

1:59:31 and never compromising on the quality and the safety.

1:59:33 Like, it's got to work and it's got to be safe.

1:59:37 But can you still go fast?

1:59:40 But in general, just having a culture of pushing the rate of iterations here.

1:59:45 Mm-hmm.

1:59:46 And building the team that wants to go build things.

1:59:48 Everyone at Helion, or at least the vast majority of Helion,

1:59:52 we hire engineers, scientists and technicians

1:59:55 and machinists are hands-on builders.

1:59:57 The company at Helion is very weird for a fusion company.

2:00:03 Today, we are 50% technicians, not scientists.

2:00:06 Nice.

2:00:07 And we have a ton of scientists,

2:00:08 because the science is critically important too,

2:00:10 but they're supported by a huge manufacturing company.

2:00:15 And our goal is to build as fast as possible.

2:00:17 Some of the other things we try to do there, vertically integrate.

2:00:20 And this is to your point on Elon Musk,

2:00:23 this is one of the things he's focused on at his companies,

2:00:26 has been how do you bring inside

2:00:29 the critical things that are going to drive timelines,

2:00:32 the things you can't just go buy as a commodity product and get it here soon,

2:00:36 and make sure that you can go build those fast.

2:00:39 And so we've done now a number of key vertical,

2:00:42 integrated manufacturing lines at Helion.

2:00:44 I think we may be the only fusion company with a conveyor belt.

2:00:48 Actually, our second one just came online now,

2:00:51 where we literally have our production

2:00:54 line manufacturing power supplies at Helion,

2:00:57 so that we can move at maximum velocity,

2:01:00 rather than finding an external consultant

2:01:03 or an external supplier to go do those.

2:01:06 Well, I love it.

2:01:08 Builder-first company, and you're also thinking about manufacturing...

2:01:11 ...throughout all of this.

2:01:13 I'm looking at the photo of Trenta.

2:01:15 It's beautiful.

2:01:16 And you can actually,

2:01:17 I can point out on this picture one perfect example of what I'm talking about.

2:01:22 So on the end is a green structure, green fiberglass.

2:01:26 This is called G10.

2:01:28 Actually, ironically,

2:01:29 one of the main structural elements we use is this G10 fiberglass material.

2:01:34 It's the same thing that's in PCB boards.

2:01:36 It's the same substrate that's in every circuit board.

2:01:39 And so we know it's strong, it's good with electricity,

2:01:43 only we get big pieces of it and machine it.

2:01:46 But even in the end, you can see the bolts halfway through.

2:01:49 There's nine bolts in the middle there.

2:01:52 The standard piece of G10 was not big enough to fit the end of the machine,

2:01:56 and so we could have had one custom

2:01:59 manufacturer manufacture a brand-new piece of a custom size,

2:02:03 build a new mold and a new machine.

2:02:05 It would have taken, I don't remember anymore now,

2:02:07 but probably on the order of, usually these are about six to 12 months.

2:02:11 Or I could go to a supplier off the shelf,

2:02:13 have that delivered in a week, and now machine it with all the bolts in between.

2:02:18 And then in-house, have the G10 machine

2:02:21 shop that can now machine the bolt holes,

2:02:24 to actually bolt those pieces together.

2:02:26 And so that's, that took extra engineering

2:02:28 and having really clever and brilliant mechanical and structural

2:02:31 engineers to figure out how to do

2:02:33 that and still meet the needs of the fusion system.

2:02:36 But that's what we tried.

2:02:38 That's the kinds of teams we try to build at Helion,

2:02:41 is folks that want to really get their hands dirty,

2:02:45 get hands-on, build things, move quickly.

2:02:48 And everywhere you can, without sacrificing quality or safety, take shortcuts.

2:02:52 That's the name of the game.

2:02:54 We've got to get fusion online as soon as possible.

2:02:57 Yeah, this is really exciting and really inspiring.

2:02:59 So, I have to ask then, what timeline do you think,

2:03:04 like first working, out there, nuclear fusion power plant?

2:03:08 When do you think?

2:03:10 Yeah, so what we've been able to do is build,

2:03:13 rapidly build, every few years, bring a new fusion system online.

2:03:18 In 2023, we signed a deal with Microsoft to build a power plant for Microsoft,

2:03:23 for one of their data centers.

2:03:25 And this is a power plant that is plugged into the grid,

2:03:29 generating electricity from fusion.

2:03:31 And with a very, very tough ambitious timeline

2:03:35 of 2028 for the first electrons from that power plant.

2:03:39 And that power plant will be powering a data center.

2:03:43 That power plant will be powering the grid that the data center is plugged into.

2:03:47 And we can get into the details of how the power grid works.

2:03:51 But yes, so Microsoft will be buying the power from that power plant.

2:03:55 Props to Microsoft for creating a hard deadline.

2:03:57 I love it.

2:03:59 They are.

2:03:59 They are.

2:04:00 And it is daily that we think about that deadline.

2:04:02 We had been working with them on and off through all of those machines,

2:04:08 through Grande, Venti, Trenta.

2:04:10 So they had seen us build, hit milestones, show that we can do fusion,

2:04:14 scale up by orders of magnitude, and then access these advanced fusion fuels.

2:04:18 So they had seen all of those things and seen the manufacturing we built.

2:04:24 We're already, right now,

2:04:26 building the manufacturing to support that power plant.

2:04:29 We're doing that today.

2:04:32 We started two years ago on doing the work around siting,

2:04:36 around the interconnects.

2:04:37 How do you plug fusion in?

2:04:39 What does it look like?

2:04:41 How do you site it?

2:04:42 What are the environmental consequences?

2:04:44 Who's gonna regulate it?

2:04:45 All of those things.

2:04:46 So we spent a lot of time already and we're on our way, and it's gonna be hard.

2:04:50 No joke about it.

2:04:51 This is tough, and it's something that I think about every day.

2:04:55 I'm sure you've had a bunch of people probably

2:04:57 still tell you that this is a pipe dream.

2:04:59 Like, this is impossible.

2:05:00 Are there days that you and the team think that this is indeed impossible?

2:05:04 Then you wake up the next day and you're like, "All right,

2:05:07 we're gonna do it anyway."- I mean, that's the thought process.

2:05:09 That's the mentality.

2:05:10 We're gonna do it anyway, let's go do it.

2:05:12 The world needs it.

2:05:13 There's no physics reason this can't be done.

2:05:15 Now it's a question of how fast can you build it?

2:05:18 And can you engineer it to be as efficient as it needs to be?

2:05:21 And those are engineering and manufacturing are ridiculously hard challenges.

2:05:26 So do not short sell that.

2:05:28 But that's the goal, and that's what we get up every day thinking about.

2:05:32 This is something I was actually just thinking about and talking

2:05:35 with some of my team in the last few days.

2:05:39 We certainly have people that say, "No,

2:05:41 this can never be done." And we had that before.

2:05:46 We had that at the very beginning of, "I

2:05:49 want to go merge these plasmas together," and folks said,

2:05:52 "Nope, that can never happen." And we went off and did it.

2:05:57 And, "You can't compress an FRC because it's unstable." In fact,

2:06:00 I actually still hear that, "FRCs are unstable." And I say, "Yes, I know.

2:06:04 Now let me introduce you to S* over E,

2:06:07 and 20 years of studies on what we know about that and how

2:06:10 we can combat that." And so we've been able to show,

2:06:13 through lots of skepticism that we can still build and iterate.

2:06:16 And there are things I don't know.

2:06:18 Let's just be totally honest.

2:06:20 As we're going to go build these things, we're gonna new hard problems.

2:06:24 If we're not doing our job,

2:06:26 if we're not discovering new hard problems, we probably didn't push hard enough.

2:06:30 We probably didn't push fast enough.

2:06:34 And I think that's really critical.

2:06:37 That we build the team and we do the hiring

2:06:41 to make sure that everybody is doing their problem.

2:06:44 Now that doesn't mean it's not a hard challenge, and to keep folks motivated.

2:06:49 Helion now is over 500 people.

2:06:51 But when we built Trenta, we were 50 people.

2:06:55 Okay.

2:06:56 So now there's, you know, over 300 humans working at Helion that didn't

2:07:02 see us build a system from a computer model,

2:07:07 bring it online and do fusion with it.

2:07:10 But even already for Polaris,

2:07:12 there are lots of humans that started for our seventh generation system.

2:07:17 When we were running Trenta, doing fusion, you know,

2:07:20 they were able to see that, see the measurements, know we were doing fusion.

2:07:23 But yet, this next machine was just a simulation.

2:07:27 And so, seeing that get built,

2:07:29 seeing that, like, it's just awe-inspiring for folks.

2:07:31 And I'll tell you, the first time that it comes online

2:07:34 and flashes pink and you see that fusion glow, it's awe-inspiring.

2:07:39 It's awe-inspiring.

2:07:41 I love that.

2:07:42 I've...

2:07:42 The fusion glow, yeah.

2:07:44 Yeah.

2:07:44 Everybody changes their Windows desktop backgrounds

2:07:47 to the fusion background, the plasma glow.

2:07:50 So how can you actually see it?

2:07:53 A couple of things.

2:07:54 So one, to get access to it, we have windows.

2:07:56 We have small windows all the way around that we look into with cameras,

2:08:00 spectroscopy, lasers,

2:08:01 other kinds of scientific diagnostics that we use to measure.

2:08:05 And so you see the light emission through that.

2:08:09 But also, it's very bright.

2:08:11 And so, the actual vacuum vessels themselves that we use are ceramic.

2:08:16 There are some versions of silicon and oxygen,

2:08:20 typically quartz, but there's also some other sintered materials.

2:08:23 And it's so bright that they can shine through those materials,

2:08:27 and so what you see is the light of not fusion.

2:08:30 When fusion's happening,

2:08:31 thermonuclear fusion is so hot that the light is in the X-ray spectrum,

2:08:35 and the human eye can't see that.

2:08:38 But as your ice-cold, one million-degree plasma,

2:08:41 when you're just getting started,

2:08:43 it's emitting photons in a range and light in a range that humans can see.

2:08:48 And so you see that bright, purple, fuchsia color.

2:08:51 And this would be, if you're doing actual cameras,

2:08:53 this would be like extremely high-speed cameras, that kind of thing?

2:08:57 We have high-speed ones and low-speed ones.

2:08:59 The traditional SLR cameras, which are the ones that represent the right color,

2:09:04 all they catch is the light, the integrated light, the flash.

2:09:08 They don't know, they can't see the plasma forming, accelerating, compressing.

2:09:13 They can't see any of those things.

2:09:16 They just see all of it integrated into one bright flash.

2:09:18 But the high-speed cameras, they can see that.

2:09:20 And so the high-speed cameras we can use to actually measure that.

2:09:24 In fact, we put special filters

2:09:25 on them to measure different wavelengths of light,

2:09:27 so we can tell, is it the hydrogen?

2:09:30 Is it the helium?

2:09:31 Is it the helium-3?

2:09:32 Who's emitting the light?

2:09:34 When are they emitting?

2:09:35 What particles are emitting the light and when?

2:09:38 And so, by using those advanced diagnostics, we can now take movies of that.

2:09:43 Though it's not as great as just seeing that flash.

2:09:47 Yeah, I mean, it's beautiful, right,

2:09:48 that human beings are able to create something like that.

2:09:50 It's truly beautiful.

2:09:51 Just out of curiosity, are there some interesting intricacies connecting nuclear

2:09:56 fusion power plant to the power grid?

2:10:00 Like, are there some constraints to the old-schoolness

2:10:04 of the power grid in, let's say, in the United States?

2:10:07 How do you get that- that Microsoft thing you mentioned,

2:10:10 how do you get from the nuclear fusion power plant to a computer with some GPUs?

2:10:17 How do we make that connection?

2:10:18 Or is that a trivial thing?

2:10:20 None of this is trivial.

2:10:22 But there are, I think, simple ways,

2:10:25 and there are some really interesting engineering ways to do this.

2:10:30 So, just from the fundamental basics, as we're doing fusion,

2:10:35 we push back on the magnetic field.

2:10:37 We recharge these capacitors that started where the electricity started from.

2:10:42 And that electricity then sits on a capacitor at high voltage,

2:10:46 DC voltage, that's steady.

2:10:48 At that point, it's reasonably easy to make 60 hertz power,

2:10:53 make traditional AC power.

2:10:54 It's the same way as you can take electricity in a battery

2:10:58 and use an inverter and just invert that to AC power.

2:11:00 And large-scale grid inverters, we know how to do pretty well.

2:11:04 One of the sort of unique things about a pulsed version of this, because

2:11:09 it's pulsed and a repetition rate between one and ten times a second,

2:11:14 we can adjust the power output.

2:11:16 And so as the grid needs more power, we can actually dial it up and down.

2:11:20 And we've been able to demonstrate that with our fusion systems.

2:11:23 The smaller ones, the smaller plasma systems, we've gone from zero, from off,

2:11:28 to all the way to 100 times a second, and shown we can do 100 hertz operation.

2:11:31 In fact, that system we ran for over a billion operations,

2:11:34 and just ran it steady all day long.

2:11:36 So each individual pulse is independent in some sense.

2:11:39 Each individual pulse is different.

2:11:41 Where you put in your fuel, you do fusion, you exhaust it...

2:11:44 Cool- ...through those pumps from eBay,

2:11:47 and then and then power output and electricity output.

2:11:51 Oh, wow.

2:11:51 But there's probably some more clever ways

2:11:53 to do this, and when we founded Helion,

2:11:56 the goal was to build low-cost baseload electricity.

2:11:59 And what we started to see working with Microsoft, working with others now,

2:12:04 that data centers are going to be one of the biggest power needs in the future.

2:12:08 We know that's coming up.

2:12:10 And what's really unique is that power in this form is direct recovery,

2:12:15 not the steam turbine part,

2:12:17 but direct electricity is already DC, which is steady,

2:12:22 which is what computers really want anyway.

2:12:24 So are there really unique ways to take DC power sitting on this capacitor,

2:12:29 and rather than going AC to the grid and having all these transmission losses,

2:12:34 just going direct DC to the data center?

2:12:36 Can you plug right in?

2:12:38 And so that's some of the things that my team is looking at now, is,

2:12:42 can you do that direct DC conversion

2:12:45 at super high efficiencies and run those GPUs directly?

2:12:48 That would be really powerful if we could figure out how to do it.

2:12:52 But those are some of the things that I think there might

2:12:54 be some unique ways that fusion and data centers can really couple together.

2:12:59 There's a whole cooling part to it too.

2:13:01 Most of my cooling is cooling semiconductors and cooling power switching,

2:13:05 just like a data center.

2:13:06 So there's a lot of interesting engineering

2:13:08 ways that we can bring those two together.

2:13:12 So a deeper integration between the power

2:13:15 plant and the thing that it's powering.

2:13:18 And it does seem like the future, quite possibly,

2:13:22 a lot of the energy that's needed will be for compute,

2:13:30 for AI-related applications.

2:13:33 So if you just look out into the future 10, 20, 50 years from now,

2:13:37 do you see nuclear fusion as a thing

2:13:40 that powers these gigantic data centers of millions of GPUs?

2:13:44 Just basically, the surface of the Earth

2:13:48 covered in compute and nuclear fusion power plants.

2:13:53 Maybe that's 100 years out.

2:13:56 So when I talk to AI experts,

2:13:58 they talk pretty routinely about the power needs for AI.

2:14:03 And in fact, in the same way in manufacturing

2:14:06 that the cost of any one thing asymptotes to the raw material,

2:14:12 for AI, the cost of computation asymptotes

2:14:15 to the power to the cost of the electricity.

2:14:18 And even more, that electricity's concentrated.

2:14:20 It's in that AI data center, that brain where all the power is,

2:14:23 where all the power is, and you really want a lot of high-energy density.

2:14:29 You want power generation right there on site.

2:14:33 So it seems like, take those two facts,

2:14:36 a really nice match between fusion, which is base load, high energy density,

2:14:41 can be sited most places, and a data center,

2:14:44 which is going to be high energy requirements in a local location,

2:14:49 and large amounts of it.

2:14:51 There's been predictions recently from energy institutes that suggest we will

2:14:56 have growth that, rather than a 2% growth per year in electricity,

2:15:00 may be a 4 or a 6% growth in electricity due to data center use.

2:15:04 I think that is probably wildly underestimating where we're moving.

2:15:11 And so,- Oh, man.

2:15:15 And so the idea that AI can grow human cognition,

2:15:20 and our ability to solve problems, we can't let it be limited by power.

2:15:25 And so I'm going to push as hard as I can so that that's not the limit.

2:15:30 Do you ever think about, like, 2050 or something like that?

2:15:33 I know you're focused on a few years out,

2:15:37 just getting a fusion power plant working.

2:15:40 But do you ever think about, like, even longer term future?

2:15:43 By what year do you think there'll be over 1000 nuclear fusion power plants?

2:15:51 So I tell the team that if we demonstrate fusion one time,

2:15:56 and that's it, then we failed.

2:15:59 But that's not enough.

2:16:01 The universe is powered by fusion.

2:16:03 Humans need to be harnessing this, and can harness this for our society,

2:16:10 for the good of society, for the good of technology.

2:16:13 And so that's something that we push towards.

2:16:17 And in fact, it's baked into how we design these machines.

2:16:23 Coils are mass produced.

2:16:24 Capacitors are mass produced, and we make them all.

2:16:27 All across the board is thinking about not what the next system's going to be,

2:16:32 but making sure we're building the manufacturing

2:16:34 and the infrastructure to build all those systems.

2:16:37 So we had a call from the White House a number of years

2:16:41 ago for the Bold Decadal Study in Fusion of how do we get fusion?

2:16:45 And it was Helion and a variety of other companies from the fusion industry.

2:16:51 And it's pretty awesome to be able to say there's a fusion industry now.

2:16:55 It's not just a one-off thing,

2:16:56 or there's a fusion experiment, or somebody has a prototype.

2:16:59 But like, there's an industry.

2:17:01 That Helion has competitors.

2:17:03 That's great.

2:17:05 I've never heard anyone so excited to have competitors.

2:17:07 But yes, that's like a serious thing.

2:17:10 That's a real possibility.

2:17:11 Yeah.

2:17:12 And the goal was how do we not just demonstrate fusion in the next decade,

2:17:16 but meaningfully deploy it and start to answer...

2:17:20 We have 4000 gigawatts of installed fossil fuel capacity.

2:17:25 How do we start replacing that with fusion in a meaningful way?

2:17:28 And how do we get to not just making a generator every few years?

2:17:33 But we want a factory,

2:17:35 a Gigafactory of these fusion generators rolling off the line,

2:17:38 one a month, one a week, one a day?

2:17:42 That's the kind of plans that I task my supply chain team with.

2:17:47 Like, how do you do this?