Creating Stars in a Bottle: The Race to Commercialize Fusion Energy (Vinod Khosla & Bob Mumgaard)

0:00Fusion is a reaction and it's the most prominent reaction in the universe. So fusion is the power inside the stars. It's the reaction that basically could never run out of fuel. You'd have what is functionally limitless clean energy. Entrepreneurs make these things happen. Without entrepreneurs like Bob, this would go on forever. And we'd never be quite there. The technology has always been 30 years away. And now, you know, instead of 30 years, we talk in terms of, you know, is it 30 months? Which is super exciting to see.

0:34Hey, I'm Mario, and this is the Generalist Podcast. You've probably heard the saying, the future's already here, it's just not evenly distributed yet. On this podcast, I sit down with the visionaries, builders, and investors, who are already living in that future, to give you a clearer window into what's coming next. Today, I'm speaking with Bob Mumgard and Vinod Khosla about what might be the most transformative energy technology of our lifetime, nuclear fusion, also known as Fusion Energy. Bob is the CEO and co-founder of Commonwealth Fusion Systems, CFS, the world's leading fusion energy company.

1:15Under his leadership, CFS has grown to 800 employees and raised more than$2 billion from climate-focused investors. Bob holds a PhD in applied plasma physics from MIT and has dedicated his career to bringing fusion from lab to market. Vinod Khosla needs little introduction. He's one of the most visionary venture capitalists of our time, the founder of Sun Microsystems and Khosla Ventures, and the backer of transformative companies like OpenAI, DoorDash, Stripe, and of course, Commonwealth Fusion Systems. In my conversation with Bob and Vinod, we discuss the wild, poetic science behind fusion energy, how CFS has accelerated the timeline for commercial fusion from being perennially 30 years out to potentially just a few years away, and what a world with abundant fusion energy might enable from super intelligent AI to brand new industries that we haven't even imagined yet.

2:15I can't tell you how much I learned from this conversation and how excited it got me about fusion's potential. My hope is that you'll walk away with meaningful lessons about how energy innovation happens, why this technology matters in an AI-powered future, and how fusion might be the key that unlocks solutions to some of our most pressing challenges. This is a new podcast, so if you enjoy today's episode, I'd love to have you subscribe and join the journey. Now, here's my conversation with Bob Mumgard and Vinod Khosla. This episode is brought to you by Brex. Fred Adler, the influential venture capitalist of the 1970s, was known for displaying decorative pillows in his office that featured a signature business philosophy.

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4:38to just have you, Bob, tell us a little bit about what fusion energy is and why it's so important, because especially as we think about AI and climate change, it feels like something that anyone who wants to look towards the future has to have at least a sort of rudimentary understanding of. Yeah, it's an area that a lot of people, you know, see maybe in a science textbook and then sort of put in the back of their mind or comic book or something like that. And And really, though, what fusion is, is fusion is a reaction. And it's the reaction that's the most prominent reaction in the universe. So fusion is the power inside the stars.

5:16It's the reaction that builds up all the atoms. And what that does is it takes the lightest elements and combines them together. And in the process, the result is a little bit less mass than what went in. And E equals mc squared. You get a lot of energy from that. In fact, it's the opposite process of nuclear fission, which is what people today know as nuclear power, in which nuclear power powers a large part of the world's energy needs. But in fusion, it's the other end of the periodic table, building atoms up. And so the sort of reason you'd want to do this is because it's a reaction that basically could never run out of fuel.

6:00So the stars don't really run out of fuel. It takes them several billion years to do that. So if you made that work on Earth, you'd have a completely new type of energy source. You'd have what is functionally limitless clean energy. And, you know, the other thing that I thought was interesting in learning a little bit about this, and it's something I've been really excited to try and educate myself on, is just Just how different fusion and fission are, such that fission can unfortunately have incidences where it goes very wrong. One of the things that I was learning about fusion is that, I don't know if fragile is quite the right word, but it is something that you have to pay very, very close attention to such that a puff of air in the wrong place can stop it from operating in the right way.

6:48You can probably explain that much better than I could. But you've got the gist of it. So, you know, in traditional nuclear fission, it's a chain reaction. So you put in a large amount of uranium or plutonium or things that you can use to make a chain reaction for nefarious purposes. Then you sort of burn it very slowly over time. And the challenge is controlling that, which we can do. Then also, when you want to shut it off, it doesn't necessarily shut off on your timescale. It actually keeps going. And that's how you get a meltdown. and it's also why you have waste that lasts thousands of years.

7:24That doesn't mean it's not safe. It just means you have to design that in and you have to accept that in your society. With fusion, the challenge is that it's the most prevalent elements, so it's not a fuel challenge. There's no chain reaction. Instead, it's how do you create the right conditions? It's sort of like brewing the right beer. If you don't get the right conditions, your beer is not going to work right. If you do, you can be magical, right? Well, fusion, those conditions are really extreme. They never occur on Earth. You have to go to big lengths to make them occur. You have to build machines to make them occur.

7:58It also means that if something's not quite right, it will stop. And as you mentioned, you can actually blow out a fusion machine with a single breath of air. Actually, a breath of air has more particles in it than all the fuel that at any given time is inside a fusion machine. We're going to talk more about some of the, well, to my mind, poetic parts of this machine, including how a breath of air can stop it from working. But Vinod, you're someone who has reliably seen the future before the rest of the world has. You've done that throughout your career from the very early days at Sun through to the present moment.

8:36You're also very well known for being one of the first outside investors in OpenAI's for-profit arm. But what is less well known is that the same year that you made that investment in OpenAI, you also invested in Commonwealth Fusion System, CFS. There's now a very clear connection between those two technologies. I'm curious if you could explain a little bit about that connection and if you saw it clearly at the time. Well, I won't claim I had that much foresight. I think both are really, really important. I think artificial intelligence is really important, and energy is really, really important.

9:15I didn't quite connect how much energy AI would use. I didn't have that foresight, but we are fortunate we are here, and we have a source of power to power that AI. Given the energy intensity of AI that we've seen over the past few years, how has it changed how you think about Bob's work and CFS? Has this become even more obvious why this is so critical? Are there other parts that have sort of come to light for you? I would say we absolutely need AI and we absolutely need fusion and independent of each other. I didn't connect the two in 2018 when I invested in both, to be honest. I did think limitless energy was going to open up a lot of possibilities.

10:07and that was the important thing and we needed clean limitless energy because of climate change but also because cheap limitless energy can do a lot of things for humanity there's a there's saying in in the fusion space from what i understand bob that you know the technology has always been 30 30 years away and i'm curious you know how you as a kid and as a young adult and you know uh eventually as an adult decided to spend your life in a field that had that dimension to it where it always felt just out of reach were you the the kid reading the the dr octopus spider man comics and you know seeing his his fusion machines were you dreaming about this from a young age uh so actually i was not there are people that are you know bona fide fusion aficionados that start really, really young, like, you know, third grade.

11:01I was not that. What I am is a history of technology person and, you know, studied how technologies go from laboratory to impact. And almost all those technologies have some element that's like, oh, it's always a long way away and it will always will be. And that's true if you're a lay person. But if you actually study the history and you look, you can see these things advancing. You can see them advancing and them speeding up, whether that's what large language models have recently done in AI, or whether that's biotech, or whether that's, you know, the railroad, that's the same pattern. And fusion, about 10 years ago, started to go through that pattern, that beginning of that pattern.

11:44I was in the field for reasons related to energy, and all of a sudden, fusion became more and more relevant as it got faster and faster. And really the last five years, you know, it's drastically picked up. And now, you know, instead of 30 years, we talk in terms of, you know, is it 30 months? That sort of type of discussion, which is super exciting to see. So if you hadn't seen sort of these dimensions changing in fusion, you know, maybe you would be doing some other part of the energy stack, it sounds like. Is that right? That's right. Yeah. You know, go where the smartest people are going, where the technologies are all overlapping, where the science is firm and fusion fits that bill.

12:30Is there, as you look sort of back in on the history of fusion, a specific person from the field that you're like, you know, this person should be better known for their contributions, but has perhaps been forgotten or isn't as widely known as they should be? Oh, I don't know if I'm in the position to be able to identify that. But I do think that the impact on the world that Fusion will have long term, like when we look back at it, there will be more household names that are right now sort of esoteric inside baseball. Amazing. Vinod, you are someone who tends to take ideas from scientific research papers.

13:13I know that your first company, which was an alternative milk business that you were trying to get off the ground in India, came from studying sort of the up-to-date research on that technology. Had you read a lot about nuclear fusion before meeting Bob in 2018, 2019? Well, I vividly remember meeting Bob and standing on top of the fusion reactor where they were doing these shots and saying, boy, this has to exist. And Bob had a plan. But, you know, my view is, just to add to Bob's question, entrepreneurs make these things happen. Very much true. It happened in electric cars. The Department of Energy had a forecast for number of electric cars in 2035 that I think Tesla exceeded in 2015 or 2016.

14:09While everybody else was sticking to traditional wisdom, Elon Musk just did it and exceeded every forecast. And I think that's happened in Fusion. On its own pace, without entrepreneurs like Bob, this would go on forever. and we'd never be quite there. But Bob took it on and we had backup plans. I remember us making a plan. If we got a 20 Tesla magnet and didn't get to Fusion, what would we do? We actually went through that discussion and made plans, the backup plans. We spent all this money and we didn't get to it. So it takes an entrepreneur to do this. And that's why I was really excited to support Bob in doing this.

14:54You talked there, Vinod, about the sort of 20 Tesla magnet, which is a big part of Commonwealth Fusion's systems history. At the time that you guys had met, there were these changes in material science that was sort of potentially setting the groundwork for that magnet. Bob, maybe you can tell us a little bit about what had changed that had made you excited to jump in the industry and what the state of play was when you met Vinod in 2018. Yeah, so I'd been in fusion for almost 10 years when I met Vinod and had watched as a confluence of different technologies and science results started to pile up.

15:35You had the ability to predict how these fusion plasmas, which are very complex, still things we don't entirely understand, you could predict them. So machine learning, large scale simulation, big compute was making inroads. And we were really, you know, for the first time seeing compute simulation make an impact on our understanding of those plasmas, those very hot plasmas. That was one area. You could also see other technologies that hadn't been applied to fusion before were developed for fast chargers and for some materials, etc. But in the fusion that I was working in and that CFS still works in as a leader in, the predominant way to harness fusion is to use magnetic fields to build a magnetic bottle.

16:22So you basically take a tiny, tiny bit of fuel and you get it really, really hot and you keep it hot using a series of magnets. And it turns out the performance of those fusion machines goes like the magnetic field to like the fourth power, super nonlinear. And any time you see something that is like very nonlinear, think like Moore's law, that's very nonlinear, right? Like that says go and crank it. And we'd cranked the magnets as far as they were ever going to go. And then there was a new material, a material science breakthrough that opened the path to even higher field magnets, to double the dynamic field.

16:58And so by about 2016, we really understood that that was going to be the thing that pushed fusion over the top. But you needed to go and take this new material and develop an entire technical stack on it of a new type of magnet. And so in 2018, we set out to do that. There was people that said that was going to take 30 years. We said we think it'll take three. We did it in just over three. And that was a big magnet in 2021 that showed that you could reach these very high magnetic fields, 20 Tesla, like a magnet that lives in aircraft carrier level. And because of that higher magnetic field, you said, you know, the magnetic field is important to sort of create the heat necessary.

17:40Is it fair? You know, am I correct in saying that more powerful magnet allowed more heat to be created in the reactor? The way to think about fusion is you've got to get to these extreme conditions that are very hot. So like 100 million degrees. We're talking like hotter than the center of the sun. Yeah, insane. Yeah, when John was talking about standing on top of a machine at MIT, that machine actually could get to those temperatures. It was at the time the hottest thing in the solar system. Yeah, I heard you say that on a different speech. And I literally chuckled out loud and turned to my wife.

18:16And my wife was like, well, what are you laughing about? I was like, I just heard the craziest thing. You know, that's part of the poetry of these machines. Anyway, sorry, go ahead. Very, very hot. But it's not enough to just make it hot. like you know if you like you know have a big furnace in your house you can make your furnace hot or make your house hot but if you have all the doors and windows open it won't stay hot and so you need to also insulate it very well and so that way when you put the heat in it it stays hot otherwise you'll never make more power than it takes to heat it up and so getting that that insulation that's what the magnetic field does it bottles up and it makes makes the makes the feel very well insulated.

18:53If you think about like your coffee thermos, you know, your coffee thermos keeps your coffee warm most of the day, all day, if you've got a good one. If that could insulate things as well as a fusion power plant insulates it, you know, it would still be warm like years later. That's what we're talking about, like really, really insulating it. And with these magnets, you could see that you could increase the effectiveness by an order of magnitude. Which anytime you see anything that you get a factor of 10, like, you know, you got to go try it. Do you ever think, Bob, that you're working on the less ambitious problem that really should be applying this technology to keeping our coffees hot?

19:38It's a complicated way to keep a coffee hot. But, you know, I wouldn't want to drink 100 million degree coffee either. Yes, that's fair enough. Vinod, you mentioned that this progress really happens because of exceptional people who refuse to accept what the status quo is, refuse to accept the projections made by top-down governmental bodies. What was it about Bob when you met him and the team that he was pulling together that made you think, this is someone who can break these norms and push us forward on a much faster timeline? I'd say a couple of things. First, this approach to energy was too important to not try.

20:20And I have a set of things I think we should try. And I'd rather say try and fail, but don't fail to try. And I think when we started, we didn't know for sure what would get in the way. We had alternative plans for a 20 Tesla magnet. We made those plans and found off ramps, but we're hoping never to use them. So it was just a great team attempting a large project. Look, without taking risk, you're not going to do something exceptional. Most people are afraid to risk, they fail to try instead of trying and failing. And I think that was the key here. Bob was willing to give it a try. He had a very solid side effect thesis behind it.

21:13So it wasn't just try without a thesis. And we assembled the right team. Bob had a great team. So it was all worth giving it a try. From my point of view, it was too important to not try. Do you remember what some of those alternatives were that you had laid out, had the magnet not worked as you'd hoped? Yeah, there were alternatives, and Bob can talk about it more than I can, but there were off-ramps we could use, very high test on magnets for windmills, for nuclear medicine, MRI machines potentially. Bob, go ahead and talk about it. Yeah, there was a bunch. And even something like the Caterpillar drive from Punt for October, right?

22:03Like high field madness can be used for lots of applications. But I think the important part was, how do you manage the risk of a big endeavor at the intersection of science and technology that you don't just take no risk, but you don't take risks that you're going to learn something that someone already knew, you need to like find the novel ways you were going to fail and try to identify those in advance, sort of pre-mortem of what that's going to look like. And then manage the risk, retire the risk, put the biggest risks earliest, go build the experiments that are going to teach you about that fast.

22:41And so while we built the 20 Tesla magnet and it was an important day that we turned it on, it works. And now we build them like every day. up until that point, like we built a lot of stuff that we, you know, really pushed the limits and broke. And you can't be afraid of that, because that's how you actually advance the cutting edge. You know, a really good experiment has like a 50 % chance of failure. That's very determinant. So that was the strategy that we brought to that. And that was different than what we'd done under government funding, for instance, where you couldn't really do that. Entrepreneurs do this all the time, but typically not in such hardware intensive physical sciences.

23:25So that was novel. And luckily we had the node and we could actually push forward in that strategy. I remember watching with excitement over hours and hours as the needle crept up to 20 Tesla. This was in watching the sort of the debut of the magnet? Yes. Amazing. Which we live-streamed for the first time we turned it on, which shows you our risk tolerance. Yes, that could have been a tough moment otherwise.

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25:02So join a community of strategic thinkers who are gaining an edge in understanding markets, technology, and business fundamentals by visiting thegeneralist.substack.com. That's thegeneralist.substack.com. We've talked a little bit already about some of the sort of just mind-bending parts of this technology, hottest thing in the solar system, the way that it interacts with a puff of air. you've said before, Bob, that, you know, it's not like a star in a bottle. It is a star in a bottle. And, you know, it really made me wonder how going through this process has potentially changed your concept of time, because usually stars are formed over, you know, maybe tens of millions of years, and you are creating a machine to manifest them.

25:56You know, I don't know how instantaneous it is, but much faster than that. And so, yeah, just curious how you think about that. I'm a scientist. So one of the great things about science is that the rules are the same everywhere, right? And so how you get to that point might be different, but the way that physics works is the way it works all places, all times. And so, you know, for a star, in order to make that reaction happen and get those temperatures, it uses the physical force of gravity. Well, it takes moving a lot of material into the right spots. That's at the timescale of astronomical.

26:33And it's the scale of literally stars. You can't do that on Earth. That's not gonna work, right? But you have, because people are clever and science is advanced, you know that you can use magnetic fields or you can use electric fields or you can use the speed to your advantage. Those are all different ways that people do fusion. And even though it's the same physics that's happening inside those machines, you get there at a different pace. And in fact, we had a machine at MIT that could recreate a plasma that's like the plasma that is the aurora borealis. And you could study it in the laboratory instead of with a telescope.

27:13That's the beauty of science. But then it's a different step to take that and actually say, okay, we understand it. We can predict it. to actually then harness it to make a product. And that's where entrepreneurship really starts is, you know, there's no set hard fast rules about how markets work at the level there is about how electric fields work. So you have to be able to bridge that. And it's been fun to watch and shepherd, you know, fusion along that journey. One of the things that struck me about, you know, watching some of your previous talks and reading about CFS is how obvious it seemed that you were thinking about scale from day one.

27:53It wasn't enough to simply make this technology work. It's important to find a way to roll it out really widely, really quickly because of this dynamic that you call competing with a molecule. And so, yeah, I would love to hear what that means to you and what the plan is to sort of make that rollout happen at scale. You know, most people, you know, they don't understand energy beyond they flip a switch or they fill up their gas tank, right? They don't understand the scale of it. When you sit down and you look at the numbers, clear-eyed, you know, you realize that energy is one of the largest things that humans do, right?

28:33One out of every$12 or so goes to energy. You know, you've got tens of millions of people working in energy. that just power plants, electrical power plants, that's tens of thousands of power plants that exist today. The first power plant was at the turn of the century. We've built that entire system up. It's one of the most amazing things that humans have done is to continually get better and better at energy, whether that was using domestic animals, crops before that, later you know hydropower and mills to electricity and nuclear power fossil fuels and what they enable for the world and so we've we've gone on this this journey it's the biggest thread that humans have done really and to think that like we're not done just because we have we have today it doesn't mean it's the end it doesn't mean that it's like there's nothing better the idea that you know digging up and burning molecules out of the ground is like the end all be all?