Distinguished Engineer

Kairos validates first MSR fuel code. The code evaluates TRISO fuel behaviour in Kairos's fluoride-salt-cooled reactor design, using data from earlier irradiation experiments to help demonstrate fuel safety and performance margins. July 24, 2026 US-based Kairos Power has completed the final verification and validation (V&V) reports for its KP-BISON fuel performance code. As the first code of its kind tailored for a molten salt reactor (MSR), it evaluates behaviour and structural integrity of TRISO (Tristructural Isotropic) fuel particles under high temperatures. Kairos Power is developing Fluoride Salt-Cooled High-Temperature Reactor (KP-FHR) technology, following an iterative approach, moving from non-nuclear engineering test units to demonstration plants and finally a commercial fleet. First concrete for Hermes 1, a 35 MWt non-power reactor designed to demonstrate nuclear heat production, was poured in May 2025. The US Nuclear Regulatory Commission (NRC) issued a construction permit for Hermes 2, a two-unit plant (35 MWt each) in November 2024 and Kairos broke ground for the facility in Oak Ridge, Tennessee in April. Validating the KP-BISON code ensures the TRISO pebbles will perform safely within the Flibe molten salt coolant environment. Flibe is a specialised molten salt mixture made of lithium fluoride and beryllium fluoride. The fuel pebbles contain thousands of poppyseed-sized TRISO particles. Each particle consists of a uranium oxycarbide fuel kernel coated with multiple protective layers of ceramic and carbon materials to prevent the release of fission products. The V&V reports will be submitted to NRC as part of the licensing basis the Hermes 2 demonstration plant. Kairos Power's safety case is based on the combination of robust TRISO fuel Flibe. TRISO fuel particles cannot melt in a KP-FHR and act as individualised containment systems that trap fission products inside. Flibe provides an additional layer of protection by absorbing any fission products that may escape during operation. This combination allows for high-temperature output at near-atmospheric pressure, eliminating the need for costly containment systems. KP-BISON was developed to measure how TRISO particles perform under different stressors within a KP-FHR reactor, including temperature and burnup (or energy extracted from the fuel), which increase pressure inside the fuel kernel. Kairos Power's Modelling and Simulation team began working with Idaho National Laboratory (INL) in 2018 to develop the models and tools within KP-BISON, a modification of the laboratory's BISON code. BISON is a fuel performance code based on experimental data that can be applied to various fuel forms, including light-water reactor fuel rods, TRISO fuel, metallic rod, plate fuel and others. Kairos Power received federal funding in 2019 to tailor the BISON code to assess the performance of its fuel kernel design within the unique operating environment of the KP-FHR and its Flibe coolant. The team selected from existing TRISO models historically used in high-temperature gas reactors to be incorporated into KP-BISON. This enabled the code to analyse and predict fuel performance margins across a range of normal and off-normal KP-FHR operating conditions. To verify KP-BISON, the team confirmed the code's accuracy by performing studies across an extensive test matrix of models and properties to ensure the code computed the correct solutions. The team then validated the code by comparing KP-BISON fuel performance results to real-world irradiation experiment data from the Department of Energy's Advanced Gas Reactor (AGR) programme, which used the same fuel specification as Kairos Power's fuel type. "This is the first set of TRISO codes related to the safety of the system that have met this milestone in the U.S., and the first time ever for an application to a salt-cooled reactor," said Ed Blandford, Kairos Power's co-founder and chief technology officer. "All of this work, which involved thousands of pages of calculations and analysis, boils down to the final tool we use to model the fuel and defend against underpredictions of failure." Because KP-FHRs operate outside of the current AGR qualification envelope, Kairos Power will use KP-BISON to support fuel irradiation testing at NRG PALLAS in the Netherlands to demonstrate the performance envelope for KP-FHR operation in line with regulatory requirements. Give your business an edge with its leading industry insights.

The U.S. Finally has two new nuclear projects underway. On offshore mining, New Jersey's offshore wind, and China's oil breakthrough April 24, 2026 Heatmap Illustration/Kairos Power Current conditions: Severe thunderstorms are pummeling the Mississippi Valley, particularly in Arkansas - Heavy rain has deluged much of the Somali capital of Mogadishu - Temperatures in the northern Indian state of Uttar Pradesh are reaching 110 degrees Fahrenheit. The top five. 1. The U.S. officially has two new nuclear projects underway. Have Bart write this on the chalkboard: I Will Not Spread Nuclear Misinformation.The Simpsons Let's, for a moment, recast The Simpsons' role in nuclear energy discourse. Rather than fearmongering with a pseudoscientific depiction of fission energy, imagine if that sign in the scene from the opening credits that reads "days without an accident" instead tracked how long it's been since the United States started work on building newer, sleeker, and more efficient reactors. Until last week, the sign would have clocked 4,539 days - 13 years since construction began on the AP1000 reactor known as Plant Vogtle's Unit 4. But last Friday, the next-generation reactor startup Kairos Power broke ground on its demonstration plant in Tennessee. Then this week, the Bill Gates-founded reactor company TerraPower started construction on its debut power plant in Wyoming. "This isn't a test reactor," Chris Levesque, president and chief executive of TerraPower, told The Wall Street Journal. "This is a grid-scale nuclear reactor that will be built in 42 months." While there's plenty of ambition to build more reactors in the U.S., the country has a very, very long way to go to even catch up with China's actual construction output. California won't be the site of any new plants anytime soon, at least until the state lifts its legislative ban on building new reactors. But keeping the state's last operating nuclear station, Diablo Canyon, running from 2030 to 2045 could offer net savings of capital and operating costs totaling more than $7.6 billion, or more than $500 million per year of continued operations, according to a new analysis by the Massachusetts Institute of Technology's Center for Energy and Environmental Policy Research. The savings "more than double when calculated relative to the current portfolio of alternatives mandated" in a state bill that lays out the renewable energy options for meeting Sacramento's 2045 climate goals. "In that case," the report states, "the total present value of savings for extending the life of" the plant "exceeds $20 billion, or more than $1.3 billion per year." 2. Energy Department enlists 90 nuclear firms in wartime reactor push. If the Trump administration achieves its goal of siring a nuclear renaissance, we're going to need a lot more reactor fuel than we currently have available. Much of that supply has come in recent years from Russia, but a U.S. law will fully ban imports in 2028. Both the Biden and Trump administrations have lavished funding on fuel enrichers. But on Thursday, the Department of Energy tapped a new tool: the Defense Production Act, the once-obscure Korean War-era statute that gives the federal government more powers to direct manufacturing. Under a newly launched Nuclear Fuel Cycle Consortium, the agency assembled representatives of more than 90 companies in the nuclear industrial base to "address all facets of the nuclear fuel supply chain including milling, conversion, enrichment, deconversion, fabrication, recycling, and reprocessing." The Energy Department also kicked off a campaign it's calling "Nuclear Dominance - 3 by 33." The program aims by 2033 to "catalyze a secure and cost competitive domestic fuel supply chain," speed up deployment of advanced reactors and reprocessing facilities, and find ways to use the DPA to speed up the buildout. Get Heatmap AM directly in your inbox every morning: 3. Interior Department launches a new offshore drilling and mining agency. The Department of the Interior is creating a new office called the Marine Minerals Administration to manage oil drilling and seabed mining in America's territorial waters. The new office, formed by reunifying two offices that had been split up after the 2010 Deepwater Horizon oil spill, threatens to weaken the environmental oversight of both the traditional oil and gas industry and the emerging mining sector. The move is "worrisome because it has the potential of bringing things back where they were, where there was this inherent conflict of interest between promotion of offshore oil and gas, and oversight safety," Donald Boesch, emeritus professor at the University of Maryland Center for Environmental Science, told The New York Times. On Wednesday, Secretary of the Interior Doug Burgum said "these unification efforts will streamline bureaucracy." 4. New Jersey admits defeat on offshore wind (for now). The New Jersey Board of Public Utilities has canceled the agreement it reached with PJM Interconnection in 2021 to develop wires and substations needed to send electricity from offshore wind turbines across the state. The board terminated the deal, Heatmap's Jael Holzman wrote, "because much of New Jersey's expected offshore wind capacity has either been canceled by developers or indefinitely stalled by President Donald Trump." Despite soaring electricity prices, "New Jersey is now facing a situation in which there will be no identified, large-scale in-state generation projects under active development that can make use of [the agreement] on the timeline the state and PJM initially envisioned," the board wrote in a letter to PJM requesting termination of the agreement. Newly-inaugurated Governor Mikie Sherrill has vowed to build new nuclear capacity in the state. As I wrote earlier this month, New Jersey became the latest state to lift its ban on new atomic energy plants. 5. 'A postcard from the future' and 'one of California's most important climate policymakers' Heatmap House kicked off San Francisco Climate Week with a day of conversations and roundtables with leading policymakers, executives, and investors. Two talks in particular are worth highlighting. * Heatmap's Robinson Meyer spoke about electricity prices with John Reynolds, president of the California Public Utilities Commission, whom Rob called "one of California's most important climate policymakers." * Rob also sat down with Mateo Jaramillo, the chief executive of the long-duration energy storage startup Form Energy, and discussed why Ireland is "a postcard from the future." The kicker. China is going all in on hydrogen as Beijing seeks ways to free itself from imported fossil fuels. Now the Dalian Institute of Chemical Physics has announced a facility in Xinjiang to use 1.5 gigawatts of wind power to produce green hydrogen mixed with an engineered material in a slurry bed reactor to transform solid asphalt into synthetic crude oil. If successful, the new process would allow China to import heavy oil and asphalt very cheaply from Central Asia and convert it into crude oil, the technology blogger TP Huang wrote on X, adding: "China is continuing work to turn crap into useful energy source by applying green electricity derivatives in its bid for energy independence."

'Building on the shoulders of titans' Kairos Power breakes ground on Hermes 2 construction. The company's first power-producing reactor will supply up to 50 megawatts to the TVA grid by 2030, fulfilling the first delivery under its landmark deal with Google. Kairos Power officially broke ground Friday on its Hermes 2 reactor in Oak Ridge, becoming the first company to receive a Nuclear Regulatory Commission (NRC) construction permit for a power-producing Generation IV reactor in United States history. The milestone puts the California-based advanced nuclear company squarely at the center of a new chapter in East Tennessee's long nuclear legacy. It also delivers on the clock to bring electrons to the grid by 2030. "We're here today to celebrate the groundbreaking event for our Hermes 2 reactor, but we're also here to celebrate a lot of the hard work that's led to this moment," said Edward "Ed" Blandford, co-founder and chief technology officer of Kairos Power. That hard work spans more than a decade of iterative development and, more broadly, more than 70 years of nuclear history on the same soil. Hermes 2 will be built on the same grounds as the former K-33 site at the East Tennessee Technology Park, one of two facilities originally constructed in the 1950s as part of the nation's effort to increase enriched uranium production. Kairos acquired the K-33 and adjacent K-31 sites in 2021 after the U.S. Department of Energy completed a historic cleanup and returned the land to the community for economic development. "Every time I come on this site, I still have chills," Blandford said. "The history, the legacy of the site, the proximity to the K-25 site - we really feel like we're building on the shoulders of titans in terms of the community here." About 150 community, government, and business leaders gathered for a half-day ceremony on Friday, which included site tours and remarks from elected officials and commercial partners. U.S. Deputy Secretary of Energy James P. Danly attended, along with representatives from Tennessee Valley Authority (TVA) and Google. U.S. Rep. Chuck Fleischmann, chairman of the House Energy and Water Appropriations Subcommittee, and Tennessee Governor Bill Lee also provided virtual remarks. An iterative path to power. Kairos has been building its presence in Oak Ridge for several years. The company successfully built and tested its non-nuclear Engineer Test Unit (ETU) Version 3 at the site, which served as a training and remote-handling platform for future reactor operations. Construction on its Hermes 1 low-power demonstration reactor began roughly two years ago and was still actively underway during Friday's ceremony. Kairos Power contracted with Barnard Construction Company, a heavy-civil construction company, to perform site work and excavation at the site in Oak Ridge. Hermes 2 is designed to build directly on the lessons learned. "We learned a lot from ETU 3 and how to apply it to Hermes 1, and we're excited to apply what we learned to Hermes 2," Blandford said. Where Hermes 1 is a low-power demonstration unit, Hermes 2 is Kairos's first commercial-scale plant, designed to supply up to 50 megawatts of electricity to the TVA grid. That power will help decarbonize Google data centers in Tennessee and Alabama - the first delivery under the pair's master plant development agreement announced in 2023. Smaller scale leads to a faster timeline. The reactor uses fluoride-salt-cooled high-temperature technology, incorporating TRISO-coated particle fuel and Flibe molten fluoride salt coolant. As Joe Hoagland, the associate laboratory director for Oak Ridge National Laboratory (ORNL) Fusion and Fission Energy and Science Directorate, said at the ceremony, all of these materials have roots in ORNL research. Current operating nuclear plants typically function at the gigawatt scale, serving millions of homes. However, Hermes 2 will operate at the megawatt scale, which Blandford says is a deliberate strategic advantage. "One of the advantages of the types of technologies Kairos is developing is that they're smaller scale, so they require less capital to build," he said. "That creates opportunities to potentially bring the construction schedule down and bring electrons to the market sooner." Kairos will fabricate reactor equipment modules at its manufacturing campus in Albuquerque, New Mexico, then ship them to Oak Ridge for assembly. Blandford explained that the factory-built approach is new in the nuclear space and has the potential to transform expectations for nuclear delivery timelines. The Hermes 2 civil structure will also use modular construction methods, including precast concrete and a seismically isolated foundation. The importance of the partnership agreement. The Google and TVA relationships give Kairos something rare in advanced nuclear: a known buyer before the plant is built. "Hermes 2 is the first power plant we're putting under our master plant development agreement with Google, and we have a partnership with TVA for the offtake of electrons," Blandford said. That pre-arranged offtake reduces market risk and strengthens the commercial case for the technology as Kairos eyes future full-scale deployments. TVA Senior Vice President and Chief Nuclear Officer Matt Rasmussen called the project a demonstration of "how advanced nuclear will strengthen our nation's energy dominance by delivering affordable, reliable power at scale." For Blandford, the Oak Ridge location is integral. "Oak Ridge has been very welcoming to us from the very beginning when we were looking for sites," he said. "It's been a terrific community for us to work with." Like what you've read?