Kairos and Samsung C&T partner up on Hermes 2

Earlier this week, Kairos Power announced a binding term sheet signed with Samsung C&T Engineering and Construction Group that will facilitate the two companies' collaboration on Kairos's Hermes 2 demonstration plant on multiple fronts.

The terms of that agreement include Samsung C&T providing up to $100 million to Kairos through a combination of direct investment and in-kind engineering services for the project. To that end, Samsung C&T also has officially joined Kairos's engineering, procurement, and construction (EPC) team to support both the delivery of Hermes 2 and future deployments of Kairos's reactor technology.

The background: Hermes 2 will be the second unit deployed by Kairos on its path to demonstrate its KP-FHR (that is, Kairos Power fluoride salt-cooled, high-temperature reactor) technology. The company envisions the commercial design as a 150-MWe plant containing two 75-MWe reactor units fueled with 19.75 percent HALEU. (If HALEU proves hard to obtain, the design can operate with lower-enriched LEU+, Kairos has said.)

In December 2023, the company received a Nuclear Regulatory Commission construction permit for its first demonstration reactor project, called Hermes. This milestone represented the first construction approval for a non-light water reactor in the United States in more than 50 years. Kairos broke ground on the 35-MWt project at the Heritage Industrial Park in Oak Ridge, Tenn., in July 2024, and is aiming to have Hermes on line in 2028.

Hermes 2, meanwhile, is planned as Kairos's first power-producing plant, featuring two 35-MWt units. The company received a construction permit from the NRC for the project in November 2024 and broke ground in the East Tennessee Technology Park (also in Oak Ridge) in April 2026.

Like its predecessor, Hermes 2 also claims a significant milestone of its own: it is the first Gen IV reactor to be involved in a power purchase agreement with a U.S. utility. That agreement, entered into in August 2025, involves the Tennessee Valley Authority and Google.

As for fuel, Kairos has a contract with the Department of Energy to receive HALEU for the first Hermes reactor and is working with BWX Technologies on a potential TRISO HALEU supply for Hermes 2.

Back to today: Speaking on Samsung C&T joining up on the Hermes project, Ed Blandford, Kairos's chief technology officer, said, "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."

Samsung C&T will initially focus on both power generation systems and balance-of-plant scope, though its role in the project may grow later on.

Learn more: In June, Nuclear News associate editor Rafael Guerrero visited Oak Ridge to talk with Blandford and other leaders at Kairos on the progress so far on both Hermes and Hermes 2. The full story, "Breaking Ground on a New Approach to Construction," is available on Nuclear Newswire.