How Rich Countries Can Build Nuclear Power Cheaply Again

Rachel Slaybaugh, nuclear scientist and partner at venture capital firm DCVC, joins Zero to explain why nuclear has become another China success story.

The turbine generator unit 1 inside the Pacific Gas and Electric Co. (PG&E) Diablo Canyon nuclear power plant in Avila Beach, California, US, on Tuesday, Aug. 5, 2025. The Nuclear Regulatory Commission granted PG&E permission to run the California facility under its current license while it reviews the application to extend the life of the state's last nuclear power plant. Photo by David Paul Morris /Bloomberg

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(Bloomberg) — Electricity demand is booming, and it’s not just because of artificial intelligence. So much so that many are ready to revisit the idea of nuclear power. Microsoft signed a $16 billion deal to reopen the Three Mile Island nuclear plant to power their data centres for the next 20 years. 

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But developed countries haven’t built more than a handful of new reactors in decades. When they have tried, the cost of those nuclear plants and the time to build them has been extraordinary. Will this renewed interest yield different results? 

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Nuclear scientist and partner at venture capital firm DCVC Rachel Slaybaugh joined Akshat Rathi on Zero to discuss how these new dreams of growing nuclear power can become a reality. Listen now, and subscribe on Apple, Spotify, or YouTube to get new episodes of Zero every Thursday. 

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Our transcripts are generated by a combination of software and human editors, and may contain slight differences between the text and audio. Please confirm in audio before quoting in print.

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Akshat Rathi  00:00

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Welcome to Zero, I’m Akshat Rathi. This week: Why the west can’t build nuclear

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Akshat Rathi  00:20

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Electricity demand is booming. And it’s not just because of AI. We are electrifying a lot of things: from cars to heating to heavy industry. And that’s got a lot of people thinking, where will all this electricity come from? And how can we make sure it’s available whenever it’s needed? 

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One of the technologies that people are turning to — or turning back to — is nuclear. In fact, the demand is so great, that in the US, previously decommissioned nuclear reactors are being turned back on. Microsoft last year signed a $16 billion deal to reopen the Three Mile Island nuclear power plant… to make sure they have enough electricity to power their data centres for the next 20 years. 

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The bigger conversation, of course, is about building out new reactors, something the West hasn’t done at scale for decades. And when it has tried in recent years, the cost of those nuclear plants and the time to build them has been extraordinary. Take the example of the Vogtle nuclear power plant in the US state of Georgia. Its two newest units built in the last two years cost $37 billion — nearly three times the original cost. Or take the Hinkley Point C plant in the UK. Its construction began in 2017 and was expected to be completed by 2025. But long delays mean it might not be operational until 2031. And, yet, there is growing interest in nuclear. So it’s worth exploring the state of the technology and whether these dreams can become a reality. 

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Some quick basics first. There are two major types of nuclear reactions that produce energy. Fission — where atoms are split. It is what all commercially operating nuclear plants use today. And fusion — where atoms are fused together. That is what some are hoping will solve our energy needs once and for all. But there is no commercial fusion plant yet.

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For the next two episodes, we’ll focus on the commercially available technology: fission. In today’s episode, we’ll specifically look at the state of large nuclear fission reactors that are in operation in around 30 countries, and how to build more of them. In next week’s episode, we’ll look at small modular reactors, which many hope will be the future of nuclear fission. In theory faster, easier and cheaper to deploy. Joining Zero for both those episodes is Rachel Slaybaugh. She is a partner focused on climate, sustain­ability, and energy at the venture capital firm DCVC. Before that, she was a tenured professor of nuclear engineering at the University of California in Berkeley.

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Akshat Rathi  3:01  

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Rachel, welcome to the show.

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Rachel Slaybaugh  3:02  

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Great to be here. Thank you so much for having me.

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Akshat Rathi  3:05  

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So we’re going to talk a lot about how Western countries can start building nuclear power plants again. But before we get into the meat of the conversation, I want to know what I can do to become a licensed nuclear reactor operator that you are.

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Rachel Slaybaugh  3:22  

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Well, I was. Not anymore. So I, as an undergrad, was a reactor operator at Penn State’s research reactor, which is a different thing than a commercial power reactor. But I studied for a year and took an exam and, you know, read lots of manuals and did lots of drills. So if you have the time and go to a facility, I’m sure you can figure it out.

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Akshat Rathi  3:46  

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Oh, that’s excellent. I mean, if it’s only a year, I think that’s manageable.

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Rachel Slaybaugh  3:50  

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Yeah, a year at a reactor that is so safe it can’t melt down. A commercial power reactor, it’s longer.

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Akshat Rathi  3:58  

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All right, let’s start with a little bit of history. First, Europe and America used to be great at building nuclear power plants. The US, even today, has the world’s largest fleet of nuclear power plants. And countries like France have a huge share of their electricity coming from nuclear, even today. But when it comes to building new nuclear, the story is really in Asia. So tell us, why did the West stop building nuclear power plants altogether? 

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Rachel Slaybaugh  4:26  

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Yeah, I mean, we stopped building them mostly due to the flattening of power demand and inflation, right? So in the early 80s, interest rates were very high. Oil shocks of the 70s, conservation became a really big deal. And so load growth in the US changed, and that was combined with really high interest rates. So even if you could build a project pretty well, a big, expensive project with a 14% interest rate is just not economic. And so that combination of things. And then nuclear fell out of public favor. There was a lot of resistance to it for various reasons. And so throughout the 80s and most of the 90s, nuclear power just wasn’t of interest in the United States. And to some extent, in Europe, but not quite as badly. It’s country by country there. And then nuclear became of interest again in the United States in the early 2000s, to begin with, when natural gas prices were really high. And so when gas was $8 an MMBtu, now nuclear power is looking pretty good. And then in the 2000s, we figured out fracking, and gas went down to $3 an MMBtu, and nobody cared about nuclear anymore, so that’s been the journey since the 70s.

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Akshat Rathi  5:44  

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And it is not that the West has not built any nuclear power plants. There’s one being built here in the UK. There was one built in the state of Georgia, in the US. The trouble has been that all these recent nuclear power plants have been very expensive. So in the UK, the average cost of power is about £70 pounds per megawatt-hour. The Hinkley C power plant, which is under construction, has been guaranteed a price of £127 pounds per megawatt-hour. So why is it that nuclear power plants in the West have become so expensive?

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Rachel Slaybaugh  6:23  

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It’s a collection of reasons. One of the reasons is the West in general, and the US especially, are very bad at mega projects. So in general, mega-projects are expensive. They are typically over schedule and over budget. And my flippant answer there is that when you add radiation, that doesn’t solve that problem, right? So we can’t build a bridge on time and on budget. Why could we build a nuclear power plant on time and on budget? So partially it’s that. The other part is that historically, we haven’t had significant load growth. And so you’re building a reactor one at a time, or maybe two at a time, and so you never get enough reps in to actually drive the cost down. So when people say first of a kind, if everything is a first of a kind, it’s more expensive. When you get to ‘nth of a kind’ — I’m putting air quotes here — that’s when you hit the actual projected costs. And in the case of large projects, n is usually like four. You don’t have to build hundreds of them to get to that cost. But when you build the same project repeatedly, even on number two compared to number one, all of the things that were maybe not 100% figured out in the design are figured out. The supply chain is exercised. The workforce has done it before, right? So part of it is we just aren’t building enough of the same thing. And then the other thing is, we’re bad at construction projects for a whole bunch of reasons. People have written about how there are too many subcontractors. And yes, if you have subcontractors that are suing each other during the project, it’s probably going to slow down and become more expensive.

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Akshat Rathi  8:04  

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I also heard from Ernest Moniz, who was the former Secretary of Energy, that the Vogtle nuclear power plant in Georgia needed 2,000 electricians, and there weren’t 2,000 electricians in rural Georgia, and they all had to be moved. And that just took so much longer. And of course, the US did not plan to build another nuclear power plant, so now those 2,000 electricians have disappeared into wherever there are electrician jobs. And that kind of problem also shows up in construction activity here in Europe. So that adds to the cost. 

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Rachel Slaybaugh  8:38  

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That’s exactly right. You can say the same thing about welders and these skilled trade positions.

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Akshat Rathi  8:44  

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So one way in which I want us to talk about nuclear is to just look at it in these five different buckets. The first bucket being the old school large-power plant design that exists that we’ve built many reactors, and countries like China are building many more of. Then there are these advanced reactors which could be safer, cheaper, and could use fuel in a more efficient way. Then there are small modular reactors, which are maybe old school or advanced, but in a small form factor. And now these days, there’s even micro-reactors, things that you could literally put in your backyard, in a shipping container, or even something smaller. And they’re all very interesting. But let’s start with the thing that exists, at scale, which is these old school reactors. What are they? And why is it that those were the reactors we built most of and continue to today?

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Rachel Slaybaugh  9:40  

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We call them large light water reactors. And by large, they actually are large, like a gigawatt of electrical output. And by light water we mean regular water, because the nuclear industry likes to name things in ways that are opaque. Sometimes there are also heavy water reactors, and that’s where the hydrogen in the water molecules have an extra nucleon in them. They have some different properties, those exist mostly in Canada. Large light water reactors. So they use water to both cool the fuel and transfer the heat. So fundamentally, a nuclear reactor is taking usually a uranium-235 atom, which is a big, heavy, unstable atom, and you add a neutron, and the addition of that neutron causes enough extra energy in the atom that it becomes so unstable it splits into two pieces, and in that process, it releases heat. So it’s just a really complicated way to boil water. So the water in light water reactors is both cooling the fuel to keep it safe, and then transferring that heat so we can use that heat to make electricity. The fuel in those reactors, it’s uranium-235, about five weight percent compared to uranium-238. I’m specifying this because there’s talk of enrichment quite a bit out in the world these days, and in nature uranium-238 is 99.3% of the uranium. And so we have to increase the 235 percentage. The fuel pellets are ceramic, so they’re very stable. Think of a coffee cup. It’s not going anywhere. It’s not a pile of ooze. It’s a ceramic material that the fuel is inside. Those are in metal tubes that are tall and skinny. We heat up the water, we create steam, and turn a turbine. 

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Why did we do it that way? It’s just the easiest way to make it happen. So there are all these properties around what energy is the neutron when it causes the fission to happen? What materials are absorbing the neutrons? Because when a fission happens, a few more neutrons are released, and those neutrons are available to go on to cause more fission. So it’s all about keeping the chain reaction steady. So a lot of what reactor design is is keeping the right number of neutrons in the system. And so it’s just easier to do that with water reactors. And also historically, you know, the nuclear navy in the United States is really where nuclear power was born. At the time, the major competing design was a sodium-cooled reactor. But sodium and water… 

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Akshat Rathi

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…do not mix.

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Rachel Slaybaugh

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…interact quite energetically, and so at the time, Hyman Rickover, the very famous Admiral of the US nuclear Navy, said, I don’t know if we can swear on the show, but I’m going to say his quote anyway. If the sea was made out of sodium, some asshole would try to put a water reactor in it. So really it was that for the nuclear navy, having a water reactor in the ocean made much more sense. And so it was kind of a VHS versus Betamax — I need a new analogy for this century — but light water reactors won out. 

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Akshat Rathi  12:52  

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Facebook versus MySpace? There are many analogies that we could come up with. But okay, let’s take a tangent here, because it’s important. You raise this point on nuclear weapons and enrichment. So my understanding of this is that, because you have to enrich uranium-235, you’re going from this 0.7% to 3% – 5% for fuel. You use the equipment, which are centrifuges, the things that the US targeted in Iran in the recent bombing attack, and those same centrifuges, or perhaps higher speed ones, could be used to enrich it all the way to 90% which is what you need for weapons grade uranium. It is important to recognize that this connection between nuclear power and nuclear weapons does exist. There are nuclear plants in countries that tend to have nuclear weapons. There are nuclear plants in other countries, but those are typically built or provided for by countries that have nuclear weapons. So there are regulations around who can have a nuclear reactor, who can provide the nuclear fuel for those reactors. And there’s a very good reason why those regulations are in place. Because if you give everybody the capacity to make highly enriched uranium, they could go all the way to a nuclear weapon, which we know North Korea has been able to do in the recent past. How much of what we talk about next could also lead to a risk of nuclear proliferation?

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Rachel Slaybaugh  14:34  

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So overall, nuclear reactors can be connected to nuclear weapons, but often aren’t, and it’s pretty straightforward to prevent that. And then there are a few of these areas where you need to watch more closely. And maybe one related point is that you correctly specified that how much material you need for a weapon is totally different than what goes into a reactor. And so, as a result, a nuclear reactor cannot explode like a nuclear weapon. They are very different physics. They’re different things. So it is on the front end of the fuel cycle, when you’re doing enrichment, that is one of the places where you really need to pay attention. And that’s why we have groups like the International Atomic Energy Agency (IAEA) that sets standards and norms and does monitoring. And so it’s totally possible to have a peaceful nuclear program and do it responsibly and transparently, and that is totally a thing. It’s also possible to have your fuel provided for you, whether you just don’t want to deal with the enrichment process, maybe your country just doesn’t need to stand up that capability, because it is kind of a pain. So there are lots of choices. And then the other one where people look is in recycling of nuclear fuel. Now that is not something that is done broadly today. France has a partial recycling process. Russia does some recycling. Japan has done some recycling. So there is some around the world, but that’s the process where you take the fuel that was used in the reactor, and when we take that fuel out, actually most of the energy is still available in it. There’s still some uranium left, and there’s actually plutonium that was created in the reactor process that can also be used to power a reactor. So you can take out that uranium and plutonium and use it again. And uranium and plutonium can be used to make weapons. And so in that recycling process, we have processes where the uranium and plutonium are never by themselves in a weapons usable form. And so it’s really about using the processes that don’t lend themselves to proliferation, and again, that transparency and accountability. So we don’t have a wide recycling program right now, but some of the advanced reactors we’ll talk about later are set up to facilitate recycling, should we choose to do so in the future.

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Akshat Rathi  16:55  

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Join us after the break, when I ask Rachel Slaybaugh why nuclear has become a China story, and if the west can ever catch up? And hey, if you’re enjoying this episode, please rate and review Zero on Apple Podcasts and Spotify. Your feedback really matters and helps new listeners discover the show. Recently, a listener who goes by DannyUtah108 said: “The Zero team does a great job evaluating new technologies, trends and industries through a journalistic lens.” Thank you DannyUtah108.

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Akshat Rathi  17:39  

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Coming to advanced reactors, one of the arguments that people have made to me is that, why are we thinking about these advanced reactors of any kind at all? We know this thing that we’ve made for the last 60-70 years safely: light water reactors. We can make many of them. And anyway, we’ve learned from engineering that the more you make something, the cheaper it gets. So why not just stick to the old stuff? And that would be the way to bring back nuclear power plants to the west. What’s wrong with that argument?

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Rachel Slaybaugh  18:11  

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Yeah, it is an argument that does hold weight, especially in some countries. Or if we really did decide, ‘hey, we’re going to build a whole bunch of reactors and drive the cost down.’ It’s possible we could do that. There are a couple of reasons why advanced reactors are attractive. One is we’re just not good at mega projects. So instead of trying to become good at mega projects, what if we did something different that we’re better at, like small modular factory manufacturing, where we tend to do better. So one of them is the economics may work out better. You’re losing on economy of scale, but if you can’t actually execute the project to get the economy of scale anyway, then we should take a different plan. And then the advanced reactors do have some features that can be desirable. So some of them, and it’s a big range of technology types, so I’ll try to speak generally, but some of them can operate at higher temperatures. So if you’re looking for decarbonized process heat, now you can have quite high temperatures that you can use for industrial processes. Also, when they’re at high temperatures, they work more efficiently, so you get more bang for your buck out of the fuel. Some of them can facilitate recycling. And so in a world where we have increased energy demand, we want to limit uranium mining. Or when you do the recycling, the waste that comes out at the end is radioactive for less time, so it’s easier to manage. You have less of it, right? So that’s a desirable property, and as I mentioned, they might be more economic. And then the last reason is it’s easier to make them in more sizes. And not every market needs a gigawatt. We don’t always want to grow a gigawatt at a time. Not every grid needs that, especially if you’re talking about more behind the meter projects. Now, if you have more sizes of reactor choices, they might be a better fit for different market applications.

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Akshat Rathi  20:07  

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And we are talking about all this now for nuclear, because there is rising power demand in Western countries as a result of AI, as a result of electric cars and heat pumps. And this change in trajectory in power demand is what is making people go: yes, we’ve got all the solar and wind, and that’s great, and we’re going to build a lot of it, maybe not in the US, given what’s happening with the politics there, but everywhere else. Yes, we’re going to support this thing, but it’s not going to provide power all the time. And for data centers, especially, we’re going to need that power all the time. But then there’s the argument, which is, if it’s going to take these light water reactors, 5-10 years to build, that’s too long. Second, if you want to build these advanced reactors, maybe smaller ones, you’re still going to have to go through the process of getting the reactor design approved, finding people who’d want to buy it, and that’s still going to take 5-10 years. The power demand for these AI hogs is right now. So what is the reason why they’re even looking at nuclear?

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Rachel Slaybaugh  21:15  

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I think there’s an expectation that, yes, there’s power demand today, and in the future, it’s going to be even bigger. And so you can cobble together the tools you have right now, which honestly is kind of challenging, because, I mean, turbines for gas plants are also five years back-ordered, right? It’s really hard to build anything right now. And so you are going to need all the tools in your tool belt, looking at 2030 and beyond, because we’re growing now. We don’t know how fast we’re going to grow. People are building data centers, but you can imagine, if you look at that growth rate, it leads to some pretty big numbers in the future. And so if you don’t start working on the nuclear reactors now, you definitely won’t have them in five years when you need them. 

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Akshat Rathi  21:58  

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Let’s just address the question that the story of nuclear right now is in Asia. It’s really in China. It is the place with nearly half of all new reactors are being built. It is the place which BloombergNEF says builds these reactors at 1/5 the cost of the most recent reactor built in the US. And China has a plan to build about 150 of these by 2035 which would make the fleet double the size of the US fleet, which is the largest currently. Why is China doing it so cheaply? And is it because it’s making the same thing again and again?

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Rachel Slaybaugh  22:36  

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Yeah, I will say there are some transparency issues that we don’t 100% know the answer, but the answer is similar in China, as it is in Korea, as it is in the other rest of the world places where reactors are being built. So it is the same exact design, and they are building it over and over again. And the infrastructure of how they build projects is much more efficient than how we do things here. When reactors are built inexpensively, they tend to be vertically integrated. You have one organization that is very well coordinated building these things, and then you have a design. You know what it is. You build it over and over, the same exact way. You have people who have done it before, both the construction managers and the project managers, as well as the welders and the electricians. So it’s that consistency and clarity of design and clarity of plan are two really big factors. You are building a thing that you know exactly what you’re building, and the orchestration of that construction is really well done, and those are the things that have been missing in the west so far. But it is not just China. It’s also Korea, the Middle East, Turkey.

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Akshat Rathi  23:53  

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But then let’s talk politics, and especially politics from both the popular side and from the policy side. Now in the US, you have gone through a whipsaw on climate policy between presidents, from Obama to the first Trump presidency to Biden to the second Trump presidency. Why do you think nuclear can have a future in the US, where this whipsaw is likely to continue? Because the polarization between parties has grown.

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Rachel Slaybaugh  24:24  

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Interestingly, nuclear has become a bipartisan issue. Really, the Biden administration was the first democratic admin to embrace nuclear, and so that crossover view of climate benefit and resilience and security. Nuclear is one of the technologies where that’s true. Geothermal is actually another one where there’s stability and domestic ownership. So it’s viewed from sort of a resilience lens, and then it also has all these climate benefits. So it’s one of the very few technologies that is agreed upon by both parties. So we’ve actually, over the last 10 years, seen increasing support for nuclear, regardless of administration.

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Akshat Rathi  25:11  

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That was a lot of fun, thank you Rachel. Next week, we’re going to talk about small modular nuclear reactors and whether they can be built at scale.

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Rachel Slaybaugh  25:21  

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Thank you, Akshat. It was great to be here.

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Akshat Rathi  25:28  

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And thank you for listening to Zero. Now for the sound of the week. That’s the sound of a balloon being popped and the echoes that follow inside the cooling tower of a nuclear power plant. If you liked this episode, please take a moment to rate and review the show on Apple Podcasts or Spotify. Share this episode with a friend or with a nuclear bro. This episode was produced by Oscar Boyd. Our theme music is composed by Wonderly. Special thanks to Eleanor Harrison-Dengate, Sommer Saadi, Mohsis Andam, and Siobhan Wagner. I’m Akshat Rathi, back soon.

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—With assistance from Eleanor Harrison-Dengate.

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