Kairos Power Completes First Phase of ETU 3 Hardware Demonstration

Highlights

• Kairos Power completed the first phase of its Engineering Test Unit 3 demonstration in Oak Ridge, Tennessee.

• Phase 1 validates aspects of precast concrete shielding design and tests remote handling and maintenance capabilities to support the Hermes 2 Demonstration Plant and Kairos Power’s commercial fleet.

• The mockup reactor cavity allowed Kairos Power to rapidly evaluate technologies in a nonhazardous environment.

The Kairos Power team has completed a new hardware demonstration leveraging the non-nuclear Engineering Test Unit 3 platform at our campus in Oak Ridge, Tennessee.  

ETU 3 is designed to help de-risk aspects of reactor construction, operations, and maintenance to enable our commercial fleet. Lessons from the project will inform our approach to deploying the Hermes 2 Demonstration Plant, which broke ground earlier this year in Oak Ridge.

Mocking Up the Reactor Cavity

In this first phase of the ETU 3 project, a cross-functional team spanning Construction, Manufacturing, and Engineering departments worked with key partners to build a reduced-scale mockup of the Hermes 2 reactor cavity. The mockup will be used to test modular shielding designs and remote maintenance capabilities for Kairos Power’s fluoride salt-cooled high-temperature reactor (KP-FHR).

The cavity consists of a reactor vessel and a precast concrete shielding structure supported by steel frames. The team rapidly installed 12 modular wall elements (including four different designs) with stepped and sinusoidal joint geometries designed to prevent radiation leakage at the seams.

Oak Ridge National Laboratory’s (ORNL) Manufacturing Demonstration Facility helped design and produce the 3D-printed polymer composite forms for the precast panels, which were later fabricated at Tindall Corporation in South Carolina and installed by Barnard Construction.

Our Salt Process Equipment Execution & Delivery (SPEED) team is developing systems to service KP-FHRs online using robotic equipment inside the reactor cavity, which can help reduce overall operations costs of our commercial plant.

For the demonstration, each panel includes steel-framed openings that will test different concrete shielding plug designs to enable process lines to pass through. Robotic arms are mounted above the reactor cavity to connect and disconnect process lines without any human entry into the enclosure or disruption to operations.

“Delivering real hardware is central to Kairos Power’s mission to enable safe and affordable commercial deployment,” said Austin Clark, a senior engineer at Kairos Power, who led the ETU 3 development effort. “Working alongside our partners, our team designed, manufactured, and delivered the components and assemblies on an accelerated timeline to advance methods for fabricating high-quality shielding structures and deploy online maintenance solutions.”

“Completing this initial demonstration with Engineering Test Unit 3 is an important step toward establishing a sustainable maintenance concept for our future fleet,” said Ed Blandford, co-founder and Chief Technology Officer at Kairos Power. “By demonstrating the interfaces between modular shielding structures and reactor equipment, and testing the remote handling tools needed to maintain and replace components, we gain a better understanding of design features that will be standardized in commercial KP-FHR deployments.”

What’s Next

The demonstration will help inform the next iterations of the Hermes 2 reactor cavity design. The facility will also serve a training platform for future operators.