Kairos Power Breaks Ground on First Power-Producing Plant. Image submitted

OAK RIDGE, TN - On April 17, Kairos Power held a groundbreaking ceremony for the Hermes 2 Demonstration Plant in Oak Ridge, Tennessee, joined by community members, elected leaders, and partners, including Google, TVA, and Oak Ridge National Laboratory. 

The reactor will build on lessons learned from the company’s non-nuclear hardware demonstrations and the Hermes 1 reactor project to improve cost and schedule certainty for Kairos Power’s future fleet.

The groundbreaking event was not only a celebration of Hermes 2 but also a recognition of the cumulative progress Kairos Power has made to date at the Oak Ridge reactor demonstration campus.  

Deputy Secretary of Energy James Danly speaks to the assembled guests. Image submitted

“This iterative approach that Kairos is taking has borne fruit in what I think is an extraordinarily rapid pace – and we’re now in the second iteration for what is going to be the first utility-scale reactor that’s going to be coming online,” said U.S. Deputy Secretary of Energy James Danly.

“With Hermes 2 moving into construction, we’re demonstrating how advanced nuclear will strengthen our nation’s energy dominance by delivering affordable, reliable power at scale,” said Matt Rasmussen, TVA Senior Vice President and Chief Nuclear Officer. “This project shows what’s achievable when industry and technology leaders align to expand U.S. nuclear capability and secure a stronger, more resilient energy future for our country.”

"The groundbreaking of Hermes 2 is a major leap forward in our efforts to accelerate the commercialization of affordable, carbon-free energy,” said Amanda Peterson Corio, Global Head of Data Center Energy, Google. “This shift toward a more efficient, factory-based manufacturing approach is a proven path toward lower-cost, cleaner power for our operations and the communities we serve."

Continuing Progress in Oak Ridge

One of the challenges in developing new energy technology is learning how to construct projects efficiently and cost-effectively. Our Oak Ridge site serves as a proving ground where we test key aspects of project delivery and pilot advanced construction techniques to help reduce costs and shorten construction schedules for the fleet. 

Crews install a seismic spring in a mockup section of the Hermes 1 foundation. Image submitted

Kairos Power is designing a seismic isolation system – a series of springs and dampers that serve as cushions between structures and their foundations – to protect reactor buildings from earthquake ground motion. After demonstrating and validating the system at a smaller scale, Kairos Power will pilot a 3D seismic isolation system in Hermes 2. Removing seismic risk lowers construction costs by enabling a fully standardized building design, flexible siting, and efficient use of building materials.
 

Building with precast concrete is another way we’re lowering costs, leveraging factory prefabrication to enhance quality control and accelerate on-site assembly. In February, we completed shielding performance testing on a precast concrete structure to measure how radiation moves through concrete walls, joints, and seams, and to determine whether the modular wall elements could provide as much protection as a solid concrete monolith. Kairos Power plans to leverage precast concrete for the Hermes reactor series and scale up the capability to streamline construction for future plants.

Initial results show that the structure performed as expected, validating its design and reinforcing the method’s potential to accelerate reactor construction while maintaining high shielding effectiveness. 


Kairos Power Enters Strategic Partnership with Oak Ridge National Laboratory

Further advancing our work in Oak Ridge, Kairos Power has entered into a $27 million strategic partnership with Oak Ridge National Laboratory (ORNL) to accelerate advanced nuclear technology development and support U.S. nuclear energy goals.

This marks the company’s fourth partnership with ORNL, which will provide ongoing access to the lab’s technical expertise and specialized facilities.

Under the partnership agreement, ORNL will produce components for reactor development and testing using advanced manufacturing techniques, enable remote maintenance systems, assess fuel performance and manufacturing methods, and complete a plan for spent fuel management in support of the Hermes series and future reactors.

Learning by Building

Kairos Power’s second non-nuclear Engineering Test Unit (ETU 2) in Albuquerque, New Mexico. Image submitted

The Engineering Test Unit program is central to the iterative development strategy, helping the team learn quickly and mitigate risk on the path to commercial deployment. The ETUs are a series of fully integrated, reactor-scale, non-nuclear hardware demonstrations that emulate the Hermes 1 reactor design and generate critical insights for the development of the first plants.

By building and validating reactor systems in iterative learning cycles before constructing our first commercial plant, Kairos aims to significantly reduce first-of-a-kind risk and avoid the costly delays that have impacted nuclear projects in the past.

Read Kairo's blog post for a closer look at how the ETU program is enabling Kairos Power’s strategy to deliver commercial reactors with cost and schedule certainty.

The ETU 2 top head assembly is attached to the reactor vessel . Image submitted

As we prepare to start up our second ETU later this year, we have reached some important technical milestones – including installing the top head onto the ETU 2 vessel assembly. The ETU 2 reactor vessel was our first to be produced entirely in-house. Closing the vessel was a highly precise operation, requiring exact alignment between the top head and its internal components to ensure fit and performance. 

Instrumentation on the vessel head will collect high-fidelity data, monitoring internal pressures, temperatures, and flow rates to confirm how molten salt, fuel pebbles, and graphite internals interact during operations.


Automating Production

Kairos Power engineers have developed a novel solution to the complex challenge of manufacturing specialized reactor safety components. 

The reactivity shutdown system features absorber assemblies that require hundreds of highly precise welds to be performed in an inert, oxygen-free environment. With no off-the-shelf solution available, engineers at our Alameda headquarters designed a custom welding glovebox automation system. The scalable capability allows us to efficiently fabricate RSS components for reactors aligned with our vertical integration strategy, eliminating the cost of outsourced specialty manufacturing and reducing supply chain risk.
 

Preparing for Nuclear Operations

Advancing Fuel Manufacturing

Principal Engineer Johan Markgraaff demonstrates a gas-purging system in the TDL Coater Development Lab. Image submitted

Kairos Power’s state-of-the-art TRISO Development Lab (TDL) in Albuquerque, New Mexico, is helping bridge the gap to commercial fuel production. Inside its walls, they are developing, testing, and optimizing systems to mass-produce poppyseed-sized TRISO fuel particles. TDL houses three processing labs and a characterization facility that work in tandem with Pebble Development Lab (PDL) to demonstrate the complete manufacturing process for proprietary annular pebble fuel form. 

In collaboration with BWXT, Kairos Power is applying the lessons learned at TDL to advance a scalable, commercially viable fuel supply for reactors and the broader advanced nuclear industry. Read the latest blog for a closer look. 


Qualifying Graphite

An engineer subjects a graphite sample to a tensile strength test. Image submitted

This spring, Kairos Power’s materials team completed a multi-year graphite qualification program to characterize manufactured ET-10 nuclear-grade graphite materials for use in advanced reactors.

The team tested nearly 3,000 graphite specimens at the Oakland, California, lab in partnership with Ibiden Co., Ltd., to measure performance and inform the development, licensing, and deployment of the Hermes series and beyond.


Developing Remote Maintenance Capabilities

Engineers test a robotic arm designed to perform maintenance tasks within the reactor cavity Image submitted

Back in Albuquerque, teams are testing and developing precursors to the automated systems that will enable remote handling and maintenance capabilities in a future reactor fleet.

Hermes 2 and future reactors will feature robotic arms controlled remotely by operators to perform high-precision tasks within the reactor enclosure, inspecting, removing, and replacing components. The robotic systems are more precise than manual methods and use digital space mapping to locate and apply tools. This approach to reactor maintenance reduces downtime and enhances safety by minimizing worker entries.

Source: Kairos Power