#485 – David Kirtley: Nuclear Fusion, Plasma Physics, and the Future of Energy

**Lex Fridman** (0:00)
The following is a conversation with David Kirtley, a nuclear engineer, expert on nuclear fusion, and the CEO of Helion Energy, a company working on building nuclear fusion reactors and have made incredible progress in a short period of time that make it seem possible like we could actually get there as a civilization. This is exciting because nuclear fusion, if achieved commercially, would solve most of our energy needs in a clean, safe way, providing virtually unlimited clean electricity. The problem is that fusion is incredibly difficult to achieve. You need to heat hydrogen to over 100 million degrees Celsius and contain it long enough for atoms to fuse. That's why the joke in the past has been that fusion is 30 years away and always will be. Just in case you're not familiar, let me clarify the difference between nuclear fusion and nuclear fission. By the way, I believe, according to the excellent sample size subreddit post by PM Goodbeer on this, the preferred pronunciation of the latter in US is nuclear fission, like vision, and in the UK and other countries is nuclear fission, like mission. I prefer the nuclear fission pronunciation, because Merica. So today's nuclear power plants use nuclear fission. They split apart heavy uranium atoms to release energy. Fusion does the opposite. It combines light hydrogen atoms together, the same reaction that powers the sun and the stars. The result is that it's clean fuel from water, no long-lived radioactive waste, inherently safe, because a fusion reactor can't melt down. If something goes wrong, the reactor simply stops, and there's no carbon emissions. On a more technical side, Helion uses a different approach to fusion than has traditionally been done. Most fusion efforts have used TacaMax, which are these giant donut-shaped magnetic containment chambers. Helion uses pulsed magneto-inertial fusion. David gets into the super-technical physics and engineering details in this episode, which was fun and fascinating. I think it's important to remember that for all of human history, we have been limited by energy scarcity. And every major leap in civilization, agriculture, industrialization, the information age, came in part from unlocking new energy sources. If someone is able to solve commercial fusion, we would enter a new era of energy abundance that fundamentally changes what's possible for us humans. I'm excited for the future. And I'm excited for super-technical physics podcast episodes. And now a quick few second mention of each sponsor. Check them out in the description, or at lexfridman.com/sponsors. It is the best way to support this podcast. We got Uplift Desk for my favorite office desk that I'm behind right now. Finn for customer service AI agents. Miro for brainstorming ideas with your team. Element for electrolytes, BetterHelp for mental health, and Shopify for selling stuff online. Choose wisely, my friends. And now on to the full ad reads. I try to make them interesting, but if you skip, please still check out the sponsors. I enjoy their stuff. Maybe you will too. To get in touch with me, for whatever reason, go to lexfridman.com/contact. All right, let's go. This episode is brought to you by Uplift Desk, my go-to for all office and podcast studio furniture. If you go back across many years, many wonderful conversations, man, just even accessing my memory for some of those conversations, I feel truly, truly lucky to get to do what I do, to get to be alive, to get to know so many incredible people, to get a chance to sit down with them. Behind, by the way, a desk I love. And I remember when I first came to Austin, I got this crappy folding table, and I think I recorded a couple of conversations. I feel like I know I didn't have anything in that space, and I don't think I yet got the Uplift Desks in. And I remember feeling like this just doesn't feel right. And when I pretty quickly got the Uplift Desks in, everything just locked into place, just like it was before. And then of course, I got the desk for the computer and then for the robotics work I'm doing. It's just Uplift Desks everywhere. You should go support them. They're amazing. I love them very much. Go to upliftdesk.com/lex and use code Lex to get four free accessories, free same day shipping, free returns, a 15 year warranty and an extra discount off your entire order. That's upliftdesk.com/lex.
This episode is also brought to you by Fin, the number one AI agent for customer service. This is the era of AI agents trying to find their niche and dominate. This is the way you create a successful company. It's not just waving hands and saying AI agents are going to change everything. You figure out problems that people have and create a system that solves those problems. And Fin does that for customer service. It has a 65% average resolution rate. It's trusted by over 5,000 customer service leaders and top AI companies, including Anthropic. Fin is powered by Fin AI Engine, which is a continuously improving system that easily allows you to analyze, train, test and deploy over and over repeat that cycle as the system gets smarter and smarter and smarter and smarter. That's kind of the thing that you need to have a system that operates in the real world. It's built to handle complex multi-step queries like returns, exchanges, disputes, delivering high quality personalized answers, just like your best human agent. Go to fin.ai.lex to learn more about transforming your customer service and scaling your support team. That's fin.ai.lex.