Samsung C&T Engineering & Construction Group has signed a binding term sheet to make a strategic investment in US-based Kairos Power and to collaborate on the commercial deployment of Kairos Power’s fluoride salt-cooled, high-temperature reactor technology (KP-FHR).
Samsung C&T will provide up to $100m through a combination of direct investment and in-kind engineering services, subject to regulatory approvals, to enable the successful delivery of the Hermes 2 Demonstration Plant in Oak Ridge, Tennessee. Samsung C&T will also join Kairos Power’s integrated engineering, procurement, and construction (EPC) team to support the delivery of Hermes 2 and future KP-FHR plants.
Kairos broke ground for the Hermes 1 Low-Power Demonstration Reactor and the Hermes 2 Demonstration Plant, at the East Tennessee Technology Park in Oak Ridge, Tennessee earlier this year. Hermes 1 and Hermes 2 are co-located advanced nuclear demonstration reactors. They use KP-FHR technology, combining TRISO fuel pebbles with a molten Flibe salt coolant to achieve robust inherent safety at low pressure. While they share the same basic architecture, they serve different roles in Kairos Power’s commercialisation timeline.
Hermes 1 was approved by the Nuclear Regulatory Commission (NRC) in late 2023 – the first non-water-cooled reactor approved for construction in the US in over 50 years. It began construction in May 2025 and is thermal only (35 MWt) producing no electricity, with heat dissipated through a dump condenser. Its sole purpose is to prove that the KP-FHR nuclear system functions reliably under real nuclear operations. Expected completion date is 2028–2029. In May, NRC extended its construction window to April 2029 to accommodate iterative engineering modifications. It is funded by Kairos Power and the Department of Energy (DOE).
Hermes 2 is the first-ever power-producing Generation IV reactor to receive an NRC construction permit. The plant consists of two 35 MWt reactor units that together will supply 50 MWe of electricity to the Tennessee Valley Authority (TVA) grid. It serves as the initial deployment under a larger master agreement with Google, which aims to bring up to 500 MWe of nuclear energy online to power its data centres in Tennessee and Alabama. Construction began in April with operation targeted for 2030.
These are supported by a series of three engineering test units (ETUs) used to test components, train workers, and iron out construction flaws in a non-hazardous environment before loading live nuclear fuel. Each ETU has been built to systematically solve a different engineering challenge. ETU 1, built at Kairos Power’s manufacturing development campus in Albuquerque (New Mexico), focused on fluid dynamics and chemistry. It completed more than 2,000 hours of pumped Flibe (fluoride-lithium-beryllium) molten salt operations proving startup, salt handling, and online refuelling systems before being decommissioned.
ETU 2, also built in Albuquerque, focused on modular manufacturing to validate the vertical integration strategy by building over 30 separate equipment modules and testing full in-house reactor vessel fabrication. Work was completed earlier this year. ETU 3, built in Oak Ridge, focuses on civil construction and safety. The team tested 12 modular precast concrete wall structures surrounding the reactor cavity mock-up to assess radiation shielding designs. The unit also served as a proving ground for the remote handling tools needed to maintain and replace reactor components safely.
ETU 3 will also host the newly launched Nuclear Center for Advanced Manufacturing and Precast (NuCAMP) initiative, partnering with ORNL and the University of Tennessee to train the local advanced nuclear workforce. The initiative was established under a Memorandum of Understanding (MOU) signed in August to bridge the gap between advanced reactor design and repeatable, real-world construction.
Kairos and Samsung C&T plan to collaborate on selected engineering and construction activities to strengthen technical and execution readiness. This builds on a trilateral memorandum of understanding signed in August by Samsung C&T, Kairos Power, and Barnard Construction to establish an early framework for reliable project execution. These three companies comprise the core of the integrated EPC team.
The division of responsibilities separates the core nuclear systems from the traditional industrial infrastructure. Under the strategic investment framework, Kairos Power holds full technical ownership of the nuclear core (nuclear island), while Samsung C&T applies its industrial infrastructure experience to manage external power generation (balance-of-plant – BOP).
The Nuclear Island encompasses the main nuclear containment area containing the core equipment. Because this scope is governed by strict nuclear safety standards and regulations, Kairos retains full internal control. This includes the proprietary core design of the KP-FHR technology and fabrication of high-precision reactor systems, modular equipment, and safety-critical components. Many of these modules will be pre-assembled at Kairos Power’s advanced manufacturing facility in Albuquerque and shipped directly to the build site. Kairo will also manage the physical supply chains and assembly of the reactor vessel as well as radioactive material handling systems and containment architectures.
The BOP consists of all supporting components and auxiliary systems required to transmit energy to the grid, but located outside the main radioactive nuclear block. Separating this block allows Samsung C&T to follow standard, cost-efficient industrial practices. This includes engineering the secondary heat-exchanger loops and thermal conversion hardware (such as steam or specialised gas turbines) as well as management of the cooling towers, standard electrical switchyards, grid-interconnection infrastructure, and non-nuclear physical buildings. Samsung C&T also evaluates early-stage blueprints for the Hermes 2 Demonstration Plant, providing insights to streamline supply chains and ensure modular pieces can be rapidly assembled by civil partners on the ground.
Historically, nuclear plants suffered massive cost overruns because entire sites were treated under ultra-stringent nuclear construction regulations. By isolating the nuclear components into a highly standardised nuclear island and delegating the rest to a veteran commercial infrastructure specialist like Samsung C&T, the project aims to dramatically lower total construction costs and expedite build timelines.
Barnard Construction Company is the heavy civil execution powerhouse and general contractor for the physical deployment of both the Hermes 1 and Hermes 2 reactor projects in Oak Ridge, Tennessee. While Kairos Power provides the brains and Samsung C&T provides the muscles for power generation, Barnard is the boots on the ground turning those concepts into physical reality.
Barnard manages the labour, heavy machinery, and physical build site at the East Tennessee Technology Park. This includes clearing the former DOE brownfield site (the K-33 gaseous diffusion footprint; drilling safety-related piers 40 feet down into solid bedrock to anchor the plant; and precision concrete pours for the base mat foundation designed to support the reactor’s seismic isolation systems.
Kairos Power’s deployment strategy relies heavily on pre-fabrication. Instead of building everything from scratch on-site, Kairos manufactures core reactor equipment modules at its campus in Albuquerque and ships them to Tennessee. Barnard is responsible for receiving these components and integrating them on-site. To prevent the costly delays that plague traditional nuclear builds, Barnard has been integrated into Kairos Power’s iterative development loops including construction of ETU-3.
By binding Barnard’s domestic civil execution track record with Samsung C&T’s global nuclear engineering oversight, Kairos Power has insulated its proprietary core technology with two layers of highly experienced builders to keep the project on schedule.
While not handling day-to-day physical construction on the EPC team, Kairos Power’s deployment strategy is backed by the Kairos Power Operations, Manufacturing, and Development Alliance (KP-OMADA). This utility consortium advises the EPC team on nuclear licensing, operator training, and grid integration. It comprises Tennessee Valley Authority (TVA) (providing local operational support for the Tennessee site), Constellation, Southern Company and Bruce Power.
“Samsung C&T’s investment and partnership reinforce the disciplined delivery model at the core of our commercialization strategy,” said Mike Laufer, CEO and co-founder of Kairos Power. “Deploying advanced nuclear energy at commercial scale requires strong, capable partners across the full project lifecycle,” said Ed Blandford, Kairos Chief Technology Officer and co-founder. “Our integrated EPC team brings together the complementary technology, engineering, manufacturing, and project-delivery capabilities needed to advance Hermes 2 and establish a foundation for broad deployment of KP-FHR technology.”
Lee Chang-wook, Head of Energy Solutions at Samsung C&T, said, “This agreement will be an important milestone for leading the next-generation nuclear power market. Through close cooperation with Kairos Power, we plan to not only successfully carry out the SMR demonstration project but also create various business opportunities in the global commercialisation market.”
DOE is supporting the development and demonstration of Kairos Power’s technology through an Advanced Reactor Demonstration Program risk reduction award, complementing Kairos Power’s substantial private investment.
