One step closer to hydrogen-boron fusion energy

McNiel: I’m joined here today by Rich Magee, the Director of Physics R&D at TAE Technologies. What got you involved in physics and what brought you to TAE?

Rich Magee: I got involved in physics just from an early love of the subject. I made my way to graduate school at University of Wisconsin and discovered plasma physics. It seemed to me at the time, a relatively rare area of physics that had extremely exciting and direct and immediate potential application that was fusion energy. A lot of physics that I was exposed to early on seemed to be — at least that I was drawn to — cosmology, astrophysics, seemed pretty far removed from everyday life here on Earth. I like to know that we’re not just moving around a pencil on paper, but that we’re actually going to build something and also have this amazing potential to change the world, and that was fusion.

McNiel: And did you go down a path where you started to discover the transmutation of elements and how everything comes from stars? Did that hit you during your educational career?

Magee: Yes, absolutely. That came much later. One story I remember, I was in freshman or sophomore year in a big auditorium, and it was a few hundred kids in this general physics class. A lot of them were pre-med students who were taking this class as, you know, a requirement.

“I like to know that we’re not just moving around a pencil on paper, but that we’re actually going to build something and also have this amazing potential to change the world, and that was fusion.”

There were very few of us in there who were actually pure physicists, and we were learning about general relativity, how gravity can bend light and slow down time and it seemed like this really esoteric theory that you could never test or actually even comprehend or understand it as reality.

And then at the end, the professor showed this famous headline from Einstein. You remember they used that eclipse in the early 20th century to prove the general theory of relativity and the headline in the “New York Times” was like, “Lights All Askew in the Heavens.” And I thought it was amazing, and I remember looking around the auditorium and half of the kids were asleep and nobody was paying attention. I was looking for somebody to share in this moment and nobody else was into it.

McNiel: It’s like, people wake up, this is like it, this is the thing that matters. I mean, what he was able to imagine. I often think about Newton calculating the orbits of all of the heavenly bodies in our solar system and just doing that out of his brain. And it just boggles my mind that the human brain can think of something like that. And when Einstein is figuring out time and light and gravity, and the fact that if you push something to the speed of light, that it becomes so incredibly massive that you can’t push it anymore. Obviously just the fact that everything that we know comes from stars. So there’s nothing more elemental in the universe than fusion.

The earliest recorded fusion event

So when you think about the fact that the common trope is “fusion’s 30 years away and always will be,” it’s really sobering to think about Arthur Eddington postulating that the sun was helium and hydrogen fusion in the 1920s, and then Rutherford actually proving it in the ’30s, with his vacuum tube device and his anodes and watts of power. Do you remember the device they built?

Magee: Yes, this was a tabletop experiment. I mean a fairly large table in a laboratory, but the technology at the time that enabled these devices were these vacuum tubes and these vacuum pumps. So it was a pretty new technology to be able to evacuate a chamber of all the atmosphere so that you can actually produce this high energy, at the time, relatively high current beam, and just fire the beam into targets and see what kind of shrapnel came out.

This was Rutherford’s big insight was that the way to really study the atom and probe the nucleus was just to shoot a beam at a target and see what came out.

McNiel: Define beam for me here. What do we mean when we say beam?

Magee: So, a proton beam at least for the first few incarnations of this device— 

McNiel: But a proton beam… I mean, you’re getting protons, I take it. And this experiment was from hydrogen, right?

Magee: Exactly. Start with a hydrogen gas and then make a discharge. So you just have an electric potential. You can think of a spark plug in the back of this vacuum tube. So the spark plug created an arc between two electrodes. That arc is actually a plasma itself fueled with regular hydrogen gas, which they had isolated by that time. And then you have a series of grids that are just electrically biased that draw out a beam of hydrogen atoms from that hydrogen plasma and focuses them and accelerates them in a beam. 

So to give you a sense of scale, these were hitting a target of about a square centimeter, relatively low currents by today’s standards, but that was limited by the power supplies that they had to operate these things.

McNiel: And this vacuum, this tube, is this like something they would do blown glass? I mean, is that how they made these things at the time?

Magee: Yeah, exactly. A lot of these physics labs in the early days of the 20th century and even earlier, had glassblowers. Like today we have machine shops because these tubes were custom made and I imagine they went through a lot of them. Once they fail, I think they’re done. The glass blower was part of the physics lab.

McNiel: So you have this probably meter long or two meter long device with glass and brass and anodes and some source of electricity, in the kilowatt range, I imagine?

Magee: Actually much smaller than that. The power of these devices was actually in the milliwatts. So these were not super high power. They were very high voltage, but very small current, and power is voltage times current.

So the really striking thing when you read those Rutherford papers is that he never mentions the word “fusion.” He doesn’t talk about energy production, he talks about transmutation. So in Rutherford’s mind, what he was doing was building out the periodic table and trying to understand the constituent particles of all of the atoms that make up the periodic table. He discovered the alpha particle, which today we know is the helium atom. He discovered the beta particle, which we know today is the electron. His lab was responsible for the discovery of the neutron. And then with these transmutations experiments, he would take a beam of protons that he generated by drawing a beam of hydrogen atoms out of a hydrogen plasma through a vacuum tube and into a target, usually a thin foil of different materials. And he would look at what came out the other side and usually it was a new element, at least in the cases he published. So you fire a beam of protons into a boron target and he saw helium atoms.

He did note in this paper as almost an aside, they knew by this point about E=mc2 and knew about the equivalence between energy and mass. And he notes that the mass of those three helium atoms is a little bit less than the sum of the masses of the proton and the boron that went into the collision. And he also calculates how much energy that would be. And he says in this kind of offhanded way, we note that this would produce 9 MeV of energy. We know that number today to be 8.7.

McNiel: Pretty good.

Magee: Pretty dang close for 1931. But he wasn’t thinking about fusion. By now Eddington had postulated that fusion was powering the stars. There were some early thinkers that had started to think about using this energy on Earth, either for constructive or destructive purposes. But it really was not the driver in this research at all.

McNiel: Right. These guys were trying to unlock the fundamental elements of the universe.

Magee: Exactly. Rutherford is considered the father of nuclear physics. So he was interested in figuring out how atoms are constructed, but fusion just wasn’t on his mind.

First measurements of hydrogen-boron fusion in a magnetically confined fusion plasma

McNiel: So, less than a hundred years later in Japan at the National Ignition Facility, there’s a magnetic confinement device, which is a stellarator, which is substantially different than what Rutherford was dealing with, which is basically a vacuum tube with anode. What took place there?

Magee: So the stellarator at the National Institute for Fusion Science in Japan is called the Large Helical Device. This is a very unique device in the history of fusion. It started in operation in 1998, so it’s been operating for over 20 years. It was the first large superconducting stellarator. So the magnetic coils that create the confining magnetic field in the stellarator are actually superconductors. So that means when you drive current in those coils, there is zero resistance and none of that current is dissipated. So technically speaking, they’re very difficult magnets to work with. They operate at very cold temperatures. You have to cool them with liquid helium, et cetera, et cetera. But once you do get them running, they don’t consume energy because none of the current in the coils is dissipated. 

So this is really attractive for a steady-state device, and that was really the NIFS mission. They were the first major fusion device to have these crazy long shots, hourslong, they can just maintain the plasma and hold it there at very high temperatures, not quite burning plasma temperatures, but 50, 100 million degrees, easy, and, and do it for an hour with no disruptions.

So the way I think of it actually is that Rutherford really pioneered using beams, not only using beams, he taught the next generation how to make them. Of course, with successive generations, we’ve gone away from vacuum tubes and we’ve gone away from mercury pumps, and the technology has gotten a lot better, but beams are still a fundamental part of physics research in general, but plasma physics research in particular. So we use beams here at TAE to diagnose the plasma actually in a very similar way to what Rutherford did. We shoot a beam in and look at what comes out and we can learn about what’s going on inside the plasma. But also we now use beams to actually heat the plasma.

So a huge challenge of fusion is getting the plasma up to the high temperatures that are required to burn the fuel. And one way you can do that is to fire beams in. So where Rutherford was firing into his target beams of 100 microamps, today here at TAE we have beams that operate at 140 amps. So, a million times the current.

McNiel: Yeah, it’s a couple orders of magnitude. That’s impressive.

Magee: And likewise at LHD. LHD has very high-energy beams — actually much higher voltages than we have here at TAE, slightly lower current — but those high-energy beams allow us to access the p-B11 reaction and that was what this paper was about.

All the ingredients for p-B11 fusion

McNiel: Right. So they’re able to produce and sustain a hydrogen plasma at high temperatures and high energy, and then they sprinkled boron onto the plasma. Is that what happened?

Magee: This device that they have, it’s called a boronization system. And this is just a kind of an ancillary system that’s not integral to making the plasma. But they found that if they sprinkle in a little bit of boron powder, the plasma subsumes that boron and distributes it over the surface of the vacuum vessel. And that boron sticks to the walls and actually acts as what we call a getter, which means that impurities from the plasma stick to it.

So if you have a thin layer of boron on the walls of your fusion device, your plasma becomes much more high purity. There’s not as many impurities in the plasma radiating away valuable energy. So they developed this boronization system just as a way to keep the machine clean. 

But what we realized with our discussions here and with the NIFS team was that during this boronization process, they were actually creating a boron plasma inside the machine. And we also realized that their beams that they had developed were of the right energy to access what’s called the first resonance of the p-B11 fusion reaction. So they didn’t really intend to, but they had all of the ingredients required there for p-B11 fusion. And we at TAE have been, as you know, interested in p-B11 fusion for 20 years, and we have been occupied to date with developing a magnetic confinement device that is capable of burning this fuel. But our focus has really been on the magnetic confinement side of things, that is developing the field reverse configuration, the FRC, and we hadn’t yet conducted experiments with p-B11 fuel. So this collaboration gave us an opportunity to do experiments with the p-B11 fuel on this other device while we continue the FRC research here at home.

McNiel: And the paper talks about the fact that this is the first proton boron fusion event in a magnetic confinement device, and that alpha particles or helium particles were detected. And that detection took place with a sensor that was designed by TAE?

Magee: Yep, that’s right. So the conditions for p-B11 were present in the LHD, but there was no way to detect those fusion events. So TAE’s contribution to this joint-research project was to design and develop and build a detector that was capable of measuring p-B11 fusion alphas in the LHD environment. Which is actually no easy task because there is a huge fluence of x-rays coming from the LHD plasma, a huge fluence of heat. So the detector, we like to put as close to the plasma as possible in order to detect these particles, but at the same time, we need to shield it from this massive flux of heat and other particles and photons. So simultaneously being sensitive enough to detect these particles, but not so sensitive that you get fried from being too close to the plasma. That was the big challenge and that was what we were able to do, and why we wrote the paper.

McNiel: And is this device something that would be incorporated into future TAE products or is it not necessary?

Magee: Yes, actually, we use similar detectors here at TAE. So on our current device, we’re not using p-B11 fuel, but we do experiments with hydrogen and isotopes of hydrogen. And so there is, for example, a fusion reaction between two deuterons, DD fusion, which produces a three MeV proton, and a little bit of energy.

We have detectors here at TAE that can detect those three MeV fusion protons. So in order to develop the alpha particle detector that was used at LHD, we took the design of our at-home proton detectors here and modified it mainly to be able to withstand the conditions inside the LHD.

McNiel: Okay, so to put all this in context, in December of last year, Lawrence Livermore had an ignition event where they bombarded a pellet of deuterium and tritium with a tremendous amount of laser energy, and it irradiated their little peppercorn pellet, which then had produced like 1.5 times the energy that went into sparking that ignition.

So that was a fusion ignition event on Earth at the lab. In Japan, they fused boron and hydrogen together in a magnetic confinement vessel and they detected alpha particles. So there was a fusion event, but it wasn’t a Q of greater than one. It wasn’t an energy experiment, it was really a fusion experiment.

Magee: Yeah, that’s right.

McNiel: And similar to if you go back to Rutherford and his vacuum tubes in his robes and whatever was going on in that laboratory in England with their mad scientists, they basically first proved that you could fuse boron and hydrogen, but that wasn’t their objective. It was really to discover the transmutation of elements. It’s kind of a Frankenstein thing, isn’t it? You know, we’re going to take these two things. It’s alchemy, isn’t it? Like, you know, 1920s alchemy?

Rich Magee: Yeah, I think a century before they were all motivated by trying to make gold in the lab, but I don’t think that was Rutherford’s driver.

What’s next for TAE

McNiel: So this is significant in that it’s the first time we’ve detected alpha particles in a magnetic confinement device. What’s next at TAE? I mean, where do we go from here?

Magee: So the amount of energy that was released in alpha particles in our experiment on the LHD was about 14 watts. So that’s enough to power an LED. Many tens of megawatts went into the beams and the superconducting magnets and the plasma. So to your earlier point, this was not a net-energy production demonstration. This was really just a first step, in my mind, an important first step because this now gives us an experimental platform to do p-B11 experiments in a thermonuclear plasma. Basically what we did was we took Rutherford’s experimental setup and stuck it inside of a superconducting thermonuclear plasma. So we’re doing Rutherford’s early experiments inside of the LHD. 

So another key similarity between what we’re doing here at TAE and what’s happening at LHD is the beams. So the concept that we’re pursuing here at TAE is called a beam-driven FRC. So you have the magnetic confinement device that we call the FRC, but they’re also these high-power neutral beams. So the reactor that we envision is actually driven by beams, and this is what’s happening in the LHD now. So we can study how the beam interacts with the plasma and how that beam actually reacts, the yield curve of the p-B11 fusion reaction and how you might tune things to optimize how many alphas you get out.

So what we’ve done is demonstrate that these tests can now be done in the lab. You can actually do p-B11 in a modern fusion experiment and make measurements. And those are the next steps. That’s what I’m really excited about.

“You can actually do p-B11 in a modern fusion experiment and make measurements. And those are the next steps. That’s what I’m really excited about.”

McNiel: That’s great. Is it fair to think about these beams as, in a way, fuel injectors because they’re carrying fuel into the plasma? Is that not the case?

Magee: They are in some cases fueling the plasma. Actually, they do fuel the plasma, but that is not their primary function. Their primary function is to heat the plasma and drive current in the plasma. So they’re really energy.

Collaborative science in the time of COVID

McNiel: Did you go to Japan? Did you go to the facility?

Magee: We did actually have the opportunity to go. It was wonderful. But not at first. This collaboration was launched during the pandemic, and Japan had pretty tight restrictions on foreign visitors entering. So it made the experiment a lot more challenging. 

What we had to do actually was we built a replica of the detector here. We built two instances of the detector. One we shipped to Japan, and one we kept here. We liked to joke that we were doing the kind of Apollo 13 model where they were using the detector in real-time over there. And whenever there was some question, we would jump in the test module here and try to debug things and figure out what was going on. A very challenging way to do experimental science. We had one of our colleagues, Ogawa-san, underneath the LHD working with the detector and calling us on Zoom and saying, “I’m measuring this funny resistance at this part in the circuit; what’s going on?” And we would try to do the same thing over here.

But eventually it worked. We got everything working. We had our run. That first run, we TAE folks were stuck on Zoom, so we were in the control room virtually. That also slowed us up a bit. We actually were not able to access the data in real-time. So I couldn’t see what the LHD folks were seeing and initial accounts were that the detector was just being swamped with noise.

We knew this was going to be the main challenge of the measurement and it wasn’t clear if we were going to be able to detect anything. And actually, I think there’s a screenshot of one of the early experiments and you can see all of us look a little morose and nobody’s smiling, just very serious.

McNiel: Science isn’t easy, my friend.

Magee: Shortly after we hung up — and the other thing is the time zone, of course, right? So Japan is like 16 hours ahead or something. So it was two or three o’clock in the morning and we disconnected from the call. We weren’t really sure what had happened. And Hiroshi and I,  — Hiroshi Gota, my colleague here at TAE, who was instrumental in this project — we were starting to look at the data and noticed that on one shot, one of the beams had cut out and then turned back on after a brief period of time. And we looked at the signal on the detector and noticed that there was a signal that was actually following that same on-off pattern.

“‘Holy cow, there’s a signal there.’ It was very cool.”

And that was when we realized that those were alphas. So that was a really cool moment. I’ve actually saved the Zoom exchange and you can see us going back and forth and Hiroshi saying, “Wait a minute. Look at 5.3 seconds. What happened there?” And then me say, “Holy cow, there’s a signal there.” It was very cool.

McNiel: Wow. Again, 5.3 seconds, which is an eternity in the plasma world, right?

Magee: Yeah, we’re used to dealing with milliseconds usually. But then we did have one follow up run, just last October. Japan lifted COVID protocols and Hiroshi and I were able to go over and actually participate in a run. And that was super cool to just be in the control room and see their device and see the cultural differences between how they do things there and how we do things here.

McNiel: What do you think is the main difference between how they run shots and how TAE does?

Magee: So culturally there’s a lot of differences. One thing we did when we first got to the lab was we would all go to the cafeteria and have breakfast. So that’s something we don’t do at TAE. I’ll also mention that their workday is much longer. We also had dinner at the lab and lunch, of course. So we would start at seven or eight in the morning and stay until seven at night. So, much longer run days. 

The other big difference about Japan is because of their history with nuclear energy, they have extremely strict regulations and protocols when it comes to anything nuclear. And there was a time where LHD was running with deuterium and so they were producing neutrons. This is of course, something you don’t need to worry about with PB 11, but with deuterium fuel, you do produce neutrons and the Japanese government required that the machine hall be totally isolated from the control room. So, whereas we operate Norm and we sit in the control room and look out the window down the mezzanine and can see the machine right there, their machine is in a concrete bunker next door. So I never saw the machine, I wasn’t allowed to cross—

McNiel: You were never even allowed to walk in and look at the machine?

Magee: You can’t cross that boundary. I saw the big vault, the concrete vault that it sits behind, But as a foreigner, I wasn’t allowed to cross that boundary.

McNiel: Do they have it on camera? Do you see it through cameras?

Magee: Yep, yep. You can see cameras. But there’s even a counter in the control room that counts neutrons when they’re operating with deuterium and they have a budget, a daily budget of neutrons. And whenever that counter gets to the budget, they’re done for the day. They’ve produced all the neutrons they’re allowed, and they have to stop.

McNiel: So Rich, you spent some time in Japan and watched how a national laboratory operates their fusion machine. How do you compare that with what a day in the life is at TAE, you know, for someone in your role as a director of Physics R&D. If you’re doing shots, what’s your typical day look like?

Magee: So a typical day at TAE, we don’t start operations till 10:00 AM but that’s just because we like to leave the machine open for the engineers and technicians in the morning. So, we have guys and gals who arrive here bright and early. Sometimes 5:00 AM if there’s work to be done. They’ll spend a few hours working on the machine, making any repairs that are necessary for the day’s operation or any modifications.

And then at about 9:30, we have a pre-ops meeting. 

Could you give an update of what the experimental goals were yesterday and what you were able to accomplish?

We used to all stand in the control room. It was a standup meeting, meant to keep it short but since COVID, it has migrated to Zoom. Kind of a pre-flight meeting. And then we start operations.

…we started working on now ramping up faster. So there’s a pretty good ramp up to about 20 milliseconds and that gets us to a fairly high field…

McNiel: Scientists have always believed that if you combine hydrogen, protons and boron that you’re going to get three alpha particles of helium. When Rutherford did it in the 30s, he estimated the amount of power that came out of that fusion reaction.

What we’re talking about today is the proof of this in a magnetic confined device, which means there’s the opportunity to sustain a hydrogen-boron plasma, which is essential to getting to a solid state, steady state plasma engine for producing electricity.

We’re just one step closer to achieving the goal of good clean energy.