Argonne assists advanced reactor development with award-winning safety software

December 1, 2023, 3:00PMNuclear NewsKristen Mally Dean
Partnerships between the nuclear industry and national laboratories are making overall codes more robust and capable. (Photo: Argonne)

The development of modern nuclear reactor technologies relies heavily on complex software codes and computer simulations to support the design, construction, and testing of physical hardware systems. These tools allow for rigorous testing of theory and thorough verification of design under various use or transient power scenarios.

Hearing opportunity opens for Hermes 2 construction permit application

November 27, 2023, 3:09PMNuclear News
Kairos Power’s Hermes 2 demonstration plant (blue-topped building on the left) is planned to be built next to the Hermes demonstration reactor. (Image: Kairos Power)

A notice of opportunity from the Nuclear Regulatory Commission was published in the November 22 Federal Register to intervene in an adjudicatory hearing on Kairos Power’s application for a construction permit to build the Hermes 2 test reactor facility in Oak Ridge, Tenn.

Kairos Power begins loading 14 tons of FLiBe into molten salt test loop

November 17, 2023, 9:30AMNuclear News
The Engineering Test Unit at KP Southwest. (Photo: Kairos Power)

In October, staff at Kairos Power’s testing and manufacturing facility in Albuquerque, N. M., began transferring 14 tons of molten fluoride salt coolant into an Engineering Test Unit (ETU)—the largest transfer of FLiBe (a mixture of lithium fluoride and beryllium fluoride) since the Molten Salt Reactor Experiment in 1969.

FEIS for Hermes construction permit recommends approval

August 22, 2023, 9:32AMNuclear News
Conceptual art of the Hermes low-power demonstration reactor. (Image: Kairos Power)

The Nuclear Regulatory Commission staff has completed its final environmental impact statement (FEIS) for Kairos Power’s application to build the Hermes demonstration reactor in Oak Ridge, Tenn., and is advising that the construction permit (CP) be issued.

“After weighing the environmental, economic, technical, and other benefits against environmental and other costs, and considering reasonable alternatives, the NRC staff recommends, unless safety issues mandate otherwise, that the NRC issue the CP to Kairos,” the FEIS states.

Kairos test reactor passes NRC safety review

June 28, 2023, 3:00PMNuclear News

The Nuclear Regulatory Commission staff has completed its final safety evaluation for Kairos Power’s application to build its Hermes advanced test reactor at a site in Oak Ridge, Tenn., the agency announced recently. The evaluation found no safety aspects precluding issuance of a construction permit for the proposed reactor.

NRC advisors give nod to Hermes construction permit

June 2, 2023, 12:00PMNuclear News
A rendering of the Hermes low-power demonstration reactor. (Image: Kairos Power)

Having completed its review of the construction permit application for Kairos Power’s Hermes test reactor early last month, the Nuclear Regulatory Commission’s Advisory Committee on Reactor Safeguards (ACRS) recently submitted its conclusions to the agency, recommending approval.

Kairos makes list of 100 most promising cleantech companies

January 13, 2023, 9:30AMANS Nuclear Cafe

Kairos Power, an Alameda, Calif.–based advanced reactor developer, announced yesterday that it has been named to Cleantech Group’s list of the 100 most innovative and promising private companies in the cleantech sector for 2023. Cleantech Group is a research and consulting services firm headquartered in San Francisco.

Draft EIS for fluoride salt–cooled test reactor now out for public comment

October 3, 2022, 3:06PMNuclear News
An artist’s rendering of Hermes. (Image: Kairos Power)

The Nuclear Regulatory Commission issued a draft environmental impact statement (EIS) recently on Kairos Power’s application for a permit to construct Hermes, a 35-MW nonpower version of the company’s fluoride salt–cooled reactor design (KP-FHR), at the East Tennessee Technology Park in Oak Ridge, Tenn.

Advanced reactor licensing and the path to cost certainty

September 20, 2022, 3:13PMNuclear NewsMike Laufer


Developing a first-­of-­a-­kind reactor is a daunting endeavor. To be successful, advanced reactor designers need to achieve cost certainty by delivering a safe and affordable product at the promised cost. To meet this goal, Kairos Power structured its approach around four key strategies: 1) achieving technology certainty through a rapid iterative approach; 2) achieving construction certainty by demonstrating the ability to build it; 3) achieving licensing certainty by proving Kairos can license it; and 4) achieving supply chain certainty by vertically integrating critical capabilities. By mitigating risk in these four key areas, Kairos Power is confident that it will get true cost certainty for our future products.

The third prong in Kairos’s strategy—achieving licensing certainty—was a key driver in the decision to build the Hermes low-­power demonstration reactor, and it remains a major workstream as the company’s construction permit application (CPA) undergoes review by the U.S. Nuclear Regulatory Commission. Licensing a new nuclear technology is no small challenge, and there are multiple approaches companies can take. Here’s a look at how we at Kairos are approaching it.

Kairos Power and Materion commission fluoride salt purification plant

July 20, 2022, 12:01PMNuclear News
(Photo: Kairos Power)

Kairos Power needs a source of high-purity fluoride salt to test its molten salt reactor design and ultimately to serve as the coolant in its grid-scale fluoride salt–cooled, high-temperature reactor (KP-FHR). As part of a cooperative development agreement with Materion Corporation, Kairos Power designed a molten salt purification plant (MSPP) that has just been commissioned at Materion’s campus in Elmore, Ohio.

Kairos Power forms advisory consortium with four nuclear utility partners

April 20, 2022, 12:00PMNuclear News

Kairos Power announced today that it has assembled an advanced nuclear development advisory consortium with four North American nuclear operators—Bruce Power, Constellation, Southern Company, and the Tennessee Valley Authority—dubbed Kairos Power Operations, Manufacturing and Development Alliance (Kairos Power-OMADA).

Input sought on Kairos test reactor construction permit

February 23, 2022, 9:30AMNuclear News

The Nuclear Regulatory Commission is requesting public input on environmental issues that the agency should ponder as it reviews Kairos Power’s application for a construction permit to build the Hermes low-power demonstration reactor at the East Tennessee Technology Park in Oak Ridge, Tenn.

In a notice published in the February 18 Federal Register, the NRC says it will conduct a scoping process to gather information necessary to prepare an environmental impact statement (EIS) for the proposed project.

Tennessee governor gives nuclear another rhetorical boost

February 3, 2022, 7:22AMNuclear News


In his annual State of the State Address on January 31, Tennessee Gov. Bill Lee offered more praise for nuclear energy, after lauding it earlier in the month during a tour of the Tennessee Valley Authority’s Watts Bar nuclear plant

“For decades, East Tennessee has been home to some of the best-kept secrets in nuclear energy and American innovation,” Lee told the state’s General Assembly. “Today, many may not realize that Tennessee derives more power from nuclear energy than from any other source. Recently, I visited the TVA’s Watts Bar nuclear facility, the last nuclear facility to be built in America, to see firsthand how nuclear power keeps our grid dependable even when the weather is not. Nuclear power is clean energy that actually works for the private sector.”

NRC issues key safety report on Kairos reactor

November 22, 2021, 3:02PMNuclear News
Artistic rendering of the Hermes low-power demonstration reactor, a scaled-down demo of the KP-FHR. (Image: Kairos Power)

The Nuclear Regulatory Commission recently issued a draft safety evaluation report indicating initial acceptance of Kairos Power’s source term methodology for its fluoride salt–cooled high-temperature reactor (KP-FHR).