Kairos Power Installs Reactor Vessel for Third Test Unit

Kairos Power announced the installation of the reactor vessel for the company’s third Engineering Test Unit (ETU), which is under construction in Oak Ridge, Tennessee. 

The ETU will be used to inform the design of Hermes — a low-power reactor that’s also under construction at the Oak Ridge site to advance the company’s commercial fluoride salt-cooled high temperature reactor.

The project is being supported through the U.S. Department of Energy’s Advanced Reactor Demonstration Program. 

Reactor Vessel Install

ETU 3.0 is a non-nuclear prototype that will be used to pilot new manufacturing techniques and construction processes to lower the cost of building the company’s commercial reactor. 

The 14-foot-tall reactor vessel was fabricated in partnership with Cambridge Vacuum Engineering and the University of SheffieldAMRC using electron beam welding technology that offers faster welding times over conventional arc welding techniques. 

Kairos Power is also working with Barnard Construction to streamline the construction of the ETU facility around the reactor vessel. The project also serves as a test bed to refine construction methods and ensure quality assurance procedures for the current construction of Hermes. 

“The installation of our third ETU reactor vessel marks a significant moment on our commercial development pathway,” said Kairos Power Chief Technology Officer and co-founder Edward Blandford. “ETU 3.0 will serve an important mission as a testing and training platform to ensure safe and efficient operation of the Hermes reactor. But, more broadly, the expertise and capabilities we gain from the ETU program will help pave the way to successfully deploy Kairos Power’s commercial fleet.”

What’s Next

The ETU 3.0 reactor vessel installation is part of a milestone-based agreement with the U.S. Department of Energy to lower the risk of developing advanced reactor technology. Hermes is the first Generation IV reactor to receive a construction permit from the U.S. Nuclear Regulatory Commission and represents a crucial step on Kairos Power’s iterative path to deploying commercial reactors. 

“Kairos Power’s novel contract with DOE allows us to remain agile while demonstrating continued progress as a responsible steward of public funding,” said Kairos Power CEO and co-founder Mike Laufer. “ARDP support is helping us to move quickly through progressively sophisticated iterations, gaining essential learning that will enable commercial deployment of our advanced reactor technology on a meaningful timeline.”

ETU 3.0 will serve as an operator training center and test platform for Hermes remote handling and maintenance equipment. The facility will also support the staging, assembly, and testing of Hermes plant equipment modules prior to installation. 

Hermes will use a TRISO fuel pebble bed design with a molten fluoride salt coolant to demonstrate the technology’s ability to produce affordable nuclear heat.  

The company’s commercial KP-FHR technology is based, in part, on DOE-sponsored Integrated Research Projects led by several universities, national labs, and international partners to advance fluoride salt-cooled high-temperature reactors. 

The commercial version of the reactor is expected to be deployed in the 2030s.