Nuclear is Here

RYAN DEHOFF: You've just completely upended and changed the entire thought process and perspective of what is possible.

DAVE POINTER: We're now on the edge of that renaissance that everybody's really been looking for.

ED BLANDFORD: But it's on the industry to actually deliver.

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KASE CLAPP: Hello everyone and welcome to The Sound of Science, the podcast highlighting the voices behind the breakthroughs at Oak Ridge National Laboratory.

MORGAN MCCORKLE:
We're your hosts, Morgan McCorkle and-

KASE:
-Kase Clapp.

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MORGAN: In this episode, we're exploring why nuclear energy is back in the spotlight - and why so much of that momentum is centered right here in East Tennessee.

KASE: Oak Ridge has always been a hub for nuclear discovery, from the Manhattan Project to the research and development that continues today. And now, nuclear is having a moment - some are even calling it a renaissance.

MORGAN: In this episode, we'll explore nuclear energy's past, present and future. We'll learn how a reactor built at ORNL in the 1960s is informing today's construction of one of the first advanced reactors in the U.S.

KASE: And we'll see how innovation - in research, partnerships, and even advanced manufacturing - is making nuclear faster, safer, and more adaptable than ever before.

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MORGAN: To start us off, we talked to Joe Hoagland, a nuclear leader at ORNL. Before coming to the lab, Joe spent more than three decades at the Tennessee Valley Authority, where he helped guide innovation, research, and regional energy strategy.

KASE: With his unique perspective on both TVA's legacy and ORNL's future, Joe's the perfect person to help us set the stage for this conversation about why East Tennessee is once again at the center of nuclear innovation.

HOAGLAND: When you think about the rich history that's here -- so the start of the Manhattan Project, and all of the research and development and ideas that went into evolving the nuclear industry going forward -- it gives this area a very rich heritage. But in more recent times, what's beginning to happen is companies are seeing the expertise at Oak Ridge National Lab.

They're seeing the practical applicability of nuclear energy from the Tennessee Valley Authority. And so they're finding this is a good place to do business. It's a good place to develop new technologies. It's a great place to develop a supply chain. And as the businesses begin to come here and develop here, they feed off of each other, right? They give each other ideas, they give each other equipment and parts.

MORGAN: The East Tennessee Economic Council is highlighting those strengths with its tagline: "Nuclear is Here." It points to the more than 200 companies in Tennessee that contribute to the nuclear industry -- about 150 of them concentrated in the Oak Ridge-Knoxville area.

HOAGLAND: We have a community who thinks nuclear is cool, right? That doesn't happen in hardly any other place in the country. So when you're talking to community leaders, you're talking to just simply people that live in the community. They all think nuclear is important. They all think it's cool and they all want to be involved in it.

KASE: But why exactly is nuclear energy back in the spotlight - in East Tennessee and across the nation?

MORGAN: For much of the last decade, electricity demand has remained fairly flat, so there wasn't much pressure to build new power plants. But that's changed quickly - demand is now surging, driven in part by the rapid growth of AI and data centers.

HOAGLAND: Nuclear when you think about that, becomes sort of the ideal player. It's stable. It lasts a very long time. It becomes, I think, the thing that ought to lead, in terms of the generation needs, not only for the region and the nation. The challenge is making it as cost effective and as reliable as the generation that we've had in the past.

KASE: When we look at the nuclear plants operating today, most of them were built decades ago - in some cases more than 50 years back. They've provided reliable electricity for generations, but the designs are from a different era.

MORGAN: Since then, new concepts have emerged - like small modular reactors that can be built more flexibly, or advanced fuels that can enhance safety and performance.

HOAGLAND: New technologies generally are more expensive because you're dealing with new things that haven't been done before. You don't have an established supply chain. You're building things that haven't been built before. And so it costs more in construction and so forth. And everybody in the industry is sort of struggling with how to take care of that sort of first of a kind cost.

KASE: One major barrier to nuclear deployment is simply the paperwork. A nuclear plant requires a license that can run thousands of pages and take years to complete.

MORGAN: And once it's submitted, the Nuclear Regulatory Commission has to review all of that material, page by page, before the project can move forward. It's a critical step for safety - but not exactly a fast one.

HOAGLAND: One of the things the lab's actually doing right now is partnering with Atomic Canyon, using our high-performance computing capabilities and AI, to be able to simplify that whole process. Right now, it takes years now to do that. Maybe we can cut it down to a few months.

I think we have a real opportunity here to actually move the ball forward, speed the ball up, if you will, in order to be able to deploy these technologies.

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KASE: Joe gave us a big-picture view of how nuclear has shaped this region and why it's such a critical part of the energy landscape.

MORGAN: To dig a little deeper into the lab's nuclear history, we're turning to Dave Pointer, with the lab's Nuclear Energy and Fuel Cycle Division.

KASE: Dave started by reminding us where it all began - with the world's first continuously operating nuclear reactor, built right here in Oak Ridge.

DAVE POINTER: I think it's very clear that this laboratory really originated with that initial Graphite Reactor construction project. Not only in its physical location, but also in the spirit that we carry forward today. In 1943, in February, a group of scientists from what was then the Clinton Works project, met with the Manhattan Project leadership and urged them to invest in a proof of principle experiment, a test to prove that we could go from the initial discovery science work done in the Chicago critical piles to scale up to a full-time, fully operating nuclear power facility that was going to produce isotopes.

MORGAN: The Graphite Reactor was built as a pilot-scale facility to demonstrate the production of plutonium, but researchers soon took advantage of its power as a scientific instrument.

POINTER: Because they didn't know a lot of things at that time about nuclear power, reactor designs and nuclear technology, they were very conservative in their assumptions as they engineered the system. So, they had a lot of extra capacity in a very large graphite facility that they could use to make measurements as they were operating this first reactor. And then before long, they decided, hey, we have this extra space that we can also use to do a little investigation, and we can make the first isotopes in large quantities that had ever been made. And we can start to understand the impact of radiation on materials. And that initial exploratory science that was done in the Graphite Reactor was really part of the inspiration for founding the national laboratories in the first place.

KASE: From that first Graphite Reactor in 1943, Oak Ridge went on to build twelve more reactors over the next two decades - exploring different fuels, shielding and applications.

POINTER: The 1950s and 60s were an exciting time in technology development. And all of the technologies that were developed in the course of World War II were being matured and transitioned to peacetime use, and nuclear science and technology was certainly a huge part of that. And as we thought about new and inventive ways to use nuclear energy, we were looking to develop advanced reactor types that could both more efficiently utilize the fuel resources that we had available and meet a much wider range of missions, beyond just producing electricity.

MORGAN: One design they were looking at involved the use of molten salt.

HISTORICAL AUDIO: Design studies and technological developments strongly indicated that molten salt breeder reactors operating on a thorium cycle could be developed to produce low-cost electricity and conserve our uranium resources.

KASE: Most of the reactors operating today are what's called light water reactors. They use ordinary water to both cool the system and slow down the reaction inside the core. The water has to stay under very high pressure - thousands of pounds per square inch - so it doesn't boil, which means the plants have to be built with thick steel and strong containment systems.

MORGAN: Molten salt reactors, on the other hand, use liquid salt instead of water. The salt stays liquid at high temperatures without being pressurized, which makes the system simpler and inherently safer. In some designs, the nuclear fuel is even dissolved directly into the salt, so that reactor can run continuously without shutting down to refuel.

POINTER: This offers a lot of safety features that are attractive for operation of nuclear facilities in complex applications. It also allows us to think about very compact reactor designs that may be transportable or factory produced and delivered, in ways that more conventional light water reactors are not. And so, the leadership team of Oak Ridge National Laboratory was instrumental in driving the development of this advanced reactor technology focused on molten salt fuels, which could provide very high temperature energy that can be used for a wide range of applications.

HISTORICAL AUDIO: Thus the laboratory's important goals of nuclear reactor development converge in the molten salt breeder reactor. The search for a stable fuel at high temperature, the urge for fluid fuels, and the capability of providing an infinite supply of electrical power at low cost.

KASE: The Molten Salt Reactor Experiment - or MSRE - went critical on June 1, 1965, right here in Oak Ridge. Three years later, it became the first reactor in history to run on uranium-233.

MORGAN: It logged more than 13,000 hours at full power before shutting down in 1969, having met its research goals. Lab Director Alvin Weinberg dubbed it the "Mighty Smooth Running Experiment."

POINTER: And the MSRE was really the first demonstration that this technology could be used successfully. And it provides an important landmark that drove not only the focus on molten salt, but also the way we think about developing advanced reactors as a whole.

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KASE: Dave reminded us how ORNL's legacy laid the groundwork for the advanced reactors now being built.

MORGAN: One of the most exciting of those is happening right here in Oak Ridge.

KASE: Kairos Power is constructing the Hermes demonstration reactor, the first advanced reactor under Nuclear Regulatory Commission approval in more than 50 years.

MORGAN: To tell us more about that project, we're joined by Kairos Power's Chief Technology Officer, Ed Blandford.

ED BLANDFORD: Our technology has very strong roots in Oak Ridge proper. The Molten Salt Reactor Experiment was built in 1964-65 in Oak Ridge, and of course ran successfully for many years. So really, the origins of molten salt reactor technology are in Oak Ridge. So in many ways for companies like Kairos, Oak Ridge - there's already has a personal connection or an identity connection to the lab and obviously the community. Bringing us to some more current and modern times, East Tennessee is a very rich area in terms of nuclear skill sets. You've got an excellent labor market in terms of the types of people that companies like Kairos are trying to attract - that runs the range from engineering talent, people that have knowledge of nuclear facilities, all the way to skilled trades and folks who are actually doing the construction and pulling the plants together. So for a variety of different reasons, East Tennessee is just a terrific place for companies like Kairos and other nuclear developers to operate.

KASE: Hermes is a demonstration project - a way to test that a new type of reactor can work safely and efficiently before scaling up to commercial power plants. Kairos plans to build two reactors - the first will operate at low power and the second will be capable of supplying electricity to the grid.

MORGAN: Together, Hermes 1 and 2 will prove out the design, safety features, and construction methods - paving the way for future commercial reactors.

BLANDFORD: So the Kairos Power reactor technology, it is unique in the sense that it's actually not been deployed in the combination that we're deploying it. We combine the historical experience from the TRISO fuel community - that's largely been demonstrated with gas reactor technology - and we combine it with a coolant that's been demonstrated for what we call a fluid fuel type design.

The reason we're doing that is we believe it gives us a very unique safety case. That safety case actually translates into the economics of the plant.

Operating plants at higher temperature but lower pressure actually allows us to design the building and have a safety case that's different from the plants that operate today. And really being able to drive costs and construction schedule down.

KASE: In simple terms, TRISO fuel is designed to withstand very high temperatures, and molten salt is extremely effective at carrying heat away from the reactor. By combining them, Kairos is designing a system that's safer, simpler, and more efficient than conventional reactors.

MORGAN: ORNL's long-standing expertise in molten salt reactors and TRISO fuel made it a natural partner for Kairos.

BLANDFORD: So we also have a very strong partnership with Oak Ridge National Laboratory - that actually goes back to even before Kairos Power was formulated. Oak Ridge National Lab was really the convening laboratory for molten salt reactor research.

We've executed a strategic partnership with Oak Ridge that will enable us to work in a few strategic areas. Those areas include fuel development - Kairos uses TRISO particle fuel, and Oak Ridge has a rich history in TRISO fuel development.

We also have a partnership with the Manufacturing Demonstration Facility, where we're working very closely not just on additive technology for producing forms, but also looking into innovative ways to ensure quality assurance for some of our construction work.

One of the unique opportunities we have is not just the technical overlap and alignment in terms of the mission of trying to deploy nuclear quickly, but we also have the proximity where we can actually work in partnership 15 minutes away from the site.

KASE: That means Kairos can draw on ORNL's decades of experience, while also working side by side with researchers just a short drive from the construction site.

MORGAN: Kairos aims for the first reactor to go critical in the 2028 timeframe, with an aggressive goal of getting electricity on the grid by 2030. That's a much faster schedule than typical nuclear projects, highlighting the urgency they feel in bringing new energy options online.

KASE: And even as they look to the future, the history of Oak Ridge is never far from mind. Kairos is building reactors on land that was once home to massive Cold War-era uranium enrichment facilities.

BLANDFORD: There's a lot of humility actually building on that site. When we started construction for Hermes one and two, the first thing we actually had to do was remove footers, duct banks, and electrical conduit that had been put in the 1950s that had been left behind.

We had drawings from the as-built from that time period, but they don't exactly match what you're going to see, because of course the country was building in a very quick time - it was a sense of urgency.

But you have a great sense of humility by building out there and appreciating the history of what was historically done there. When K-25 was built, it was the largest building that stood in world. Just the sheer size and what was accomplished - it's a special place for Kairos to operate.

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MORGAN: Ed gave us a great look at how the Hermes project is moving nuclear forward with innovative reactor design and strong partnerships with ORNL.

KASE: The next question is-how do you actually build it? That's where advanced manufacturing comes in. We talked with Ryan Dehoff, who leads ORNL's Manufacturing Demonstration Facility, or MDF, which has spent more than a decade pushing the boundaries of the field.

MORGAN:When MDF began, most people thought of 3D printing as a small-scale tool. Ryan says they were already thinking much bigger.

RYAN DEHOFF: If you go back 15 years ago when we started this, what we saw was that the technology was not where it needed to be. We had a lot of industry partners that were wanting the technology to be able to do more, and that includes reliability. They needed it faster. They needed things cheaper. They needed to be able to productionize it. Everybody said bigger, faster, cheaper. And most people were familiar with desktop printers, and what that technology was and what the technology could do, but we were talking about making printers that were 20 feet, 30 feet in size and scale, and needing to scale the materials and the processes and the systems.

KASE:Advanced manufacturing combines the speed and flexibility of prototyping with the precision and efficiency of industrial production.

DEHOFF: What we're looking at is understanding how can you take technologies like advanced manufacturing that are really about prototyping, getting a quantity of one and doing it perfect, but at the same time taking advantage of all the traditional things about manufacturing of lower cost, better quality, higher production rates.

MORGAN: That approach led to partnerships with companies like Kairos Power, which turned to Oak Ridge when traditional manufacturing couldn't meet their needs.

KASE: Their challenge was to create precise molds for their reactor's bioshield - the thick concrete structure that protects people from radiation.

DEHOFF: Traditional steel molds are very expensive. They would even be very difficult or hard to fabricate for this particular application. Traditional wooden molds that you may use in concrete production -- they didn't think that they could achieve the geometrical accuracy and tolerances required for approval with the NRC.

And so we talked with them and it seemed like a perfect fit for where we could take the technology, use our industrial partners, help them scale the technology.

MORGAN: What happened next shows just how transformative advanced manufacturing can be.

DEHOFF: We got approval from DOE, worked with Kairos on what their design needed to look like. We designed the molds, printed a version, and poured concrete into that preliminary version of the mold - within two weeks. That timeline is unheard of.

And so to be able to go and say, within two weeks, we had a mold which we never had before, and then to go from a mold that we never had before to an actual column within their bioshield and do that in months. You've just completely upended and changed the entire thought process and perspective of what is possible.

KASE: Building on that success, the team applied the same approach to modular construction. Using 3D-printed molds, they could cast massive interlocking concrete blocks - some as long as 30 feet - that fit together to form the structure of the plant.

DEHOFF: Think of it as extremely large Lego blocks that would be put together in order to build their nuclear facility, the actual building infrastructure. And so they need these blocks to have specific characteristics, very complex shapes. The question was how do you do this? And we were able to leverage a collaboration that we have with the University of Maine that they have one of the largest printer systems in the world. We've co-developed that in collaboration with them.

MORGAN: By rethinking how these massive structures are built, Kairos and the ORNL team are showing that advanced manufacturing can deliver both precision and scale - and do it in record time.

DEHOFF: Timeline is everything. These are billions and billions of dollars, right? Well, if you have to start financing that now and it's going to be ten years, five years till you can actually start making your money back. That's a huge money sink. And there's a lot of companies that just can't shell out that kind of cash. And so, if you can shrink the timeline, you completely change how things are manufactured and accelerate the cost. It's 100% linked.

MORGAN: And this isn't just Kairos- the lab is already testing 3D-printed components inside operating reactors, proving that these new materials can stand up to real-world conditions.

KASE: In 2021, ORNL worked with Framatome and TVA to 3D-print four fuel assembly brackets that were installed at Browns Ferry Nuclear Plant in Alabama.

MORGAN: It was the first time 3D-printed components had ever been placed in a commercial U.S. nuclear reactor. And it marked a major step forward in proving that 3D-printed components can meet the industry's rigorous safety and qualification standards.

KASE: And for Ryan, this is only the beginning. He says additive manufacturing will continue to expand from support parts like brackets and molds to even more complex, safety-critical components in the years ahead.

MORGAN: One of his dreams is to produce a pressure vessel - the metal container that holds nuclear fuel - for ORNL's High Flux Isotope Reactor, HFIR, for short.

DEHOFF: I think that pressure vessels are an incredible opportunity for the U.S. Currently for the light water reactor fleet, these are the very large nuclear reactors, we do not have the ability to manufacture those vessels in the U.S, and so we source all of those vessels from overseas.

When you go to smaller vessels, we can make those today. There are people in the U.S. that can make those domestically, maybe not at the quantities that are predicted for future nuclear. The HFIR vessel in particular - I would love to be able to fabricate that vessel. I think that actually working with DOE and understanding how we could get that approved for use would be an incredible demonstration case that we can control, we can monitor, we can understand, we can learn from, and then we can help de-risk that technology for industry such that they can scale it in the future.

KASE: Ryan says this intersection of advanced manufacturing and next-generation nuclear - both maturing at the same time - is creating real momentum.

DEHOFF: It's 100% that nexus. I think that the big takeaway for me, is all the people that are questioning is that nuclear renaissance going to happen again? The answer to me, it's undoubtedly yes, it is going to happen. We are going to turn on advanced reactors that's going to be incredibly beneficial. But I actually see a future beyond that where we are going to be in mass production of these reactors. And I think that's what we need to be thinking about. And how do we scale to those things. And I do believe that advanced manufacturing will play an incredible role in that.

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MORGAN: Ryan's optimism captures something we've heard again and again in our conversations - that what's happening in Oak Ridge and across East Tennessee aren't isolated experiments. They're part of a larger movement to modernize nuclear energy for a new era.

KASE: From materials and manufacturing to licensing and reactor design, the pieces are finally coming together.

MORGAN: So - are we really witnessing a nuclear renaissance? We put that question to our guests. Here's Dave Pointer.

POINTER: I feel like we're now on the edge of that renaissance that everybody was really looking for, where we start to see some of these advanced reactor technologies become reality. I mean, it's exciting that there are advanced reactor construction projects that are active in six states. And, that's not just one that's being built, but we have commitments to move forward with some number.

I do feel like we're at the edge of a renaissance, in demonstration of the effectiveness of this technology, you know, and a new generation of scientists and engineers and operators, has the opportunity to see the impact that they can have in making these facilities real.

KASE: That sense of momentum is something we heard across the board - but it comes with responsibility. For Kairos Power's Ed Blandford, optimism alone isn't enough.

BLANDFORD: From my standpoint, there's a lot of things high-level that look great for the nuclear industry in terms of deploying quickly, but it's on the industry to actually deliver.

MORGAN: And for Joe Hoagland, no matter what you call it, the stakes are simply too high for nuclear to fall short.

HOAGLAND: If we can't deploy it effectively in the next few years, not only are we going to lose out on the nuclear energy part of things, but I think we have then the potential to fall behind in the areas of AI. I think we have the potential to fall behind economically in just general security and economic competition globally, because we're not going to be able to meet the power demands that I think we have going on. So it's extremely important, I think, that this is successful this time. So that makes it super exciting. It also makes it a little daunting, but that's worth it.

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MORGAN: Thanks for joining us for this first episode of our nuclear mini-series.

KASE: Be sure to tune in next time, when we'll take a closer look at the nuclear fuel cycle.

MORGAN: Until next time.