In July 17, 2024, Kairos Power broke ground on the first Generation IV reactor in the United States, officially licensed at Oak Ridge, Tennessee. This is a major step; it is also the first non-light-water reactor to be constructed within the country in 50 years. An important complement to this project is that a non-nuclear demonstration unit is being built simultaneously to help visualize design concepts and have operational knowledge of the new reactor facility.
While the United States has been at the forefront of developing nuclear power for civilian purposes, it has not managed to keep up with countries like China and India for various political and economic reasons. But the interest in advanced nuclear technologies has been revived by the need to help satisfy carbon reduction commitments cost-effectively while maintaining a secure supply of low-carbon electricity to power modern industrial economies. The new reactor, Hermes, is a low-power demonstrator, aimed at proving technology readiness level four for Kairos’s molten fluoride salt-cooled pebble-bed reactor technology—recognized for its passive safety characteristics.
The Hermes reactor will not produce electricity for the grid but will instead focus on refining the design and safety of the pebble-bed reactor. This reactor uses spherical pellets of enriched uranium, carbon, and ceramics known as TRi-structural ISOtropic (TRISO) particles, which act as tiny nuclear pressure vessels. These particles are formed into large pebbles that sustain the nuclear reaction. Unlike similar reactors cooled by helium gas, Hermes uses molten fluoride salts to cool the reactor core, maintaining a temperature of 1,085 °F (585 °C).
In addition to Hermes, Kairos Power is constructing ETU 3.0, a non-nuclear version of the reactor, to allow engineers to study the system without the complexities of radiation. This test bed aims to make the construction and operation of nuclear stations more economical by focusing on the major costs associated with civil engineering.
Hermes is designed to be modular, with parts constructed and tested at a plant in Albuquerque, New Mexico, and then sent to Tennessee. With funding from the Department of Energy totaling $303 million, this project should be finished by 2027. The CEO of Kairos Power, Mike Laufer, stressed how the project has the potential to completely change the energy environment and highlighted the priceless lessons that can be drawn from the building and maintenance of Hermes.
While the government considers Bill Gates’s reactor project in Wyoming, Kairos Power’s advancement is a critical step toward the U.S.’s adoption of cutting-edge nuclear reactor technology.
