Hermes 2 – Kairos Application

image of Kairos - Hermes 2
Who:   Kairos Power LLC
What:   Application for a construction permit for an advanced test reactor
When:   July 14, 2023 (date of application submittal)
Where:   Oak Ridge, Tennessee

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Project Overview

The staff of the U.S. Nuclear Regulatory Commission (NRC) is currently engaged in review activities of the Hermes 2 construction permit application. Kairos Power LLC, is a U.S. based company developing a fluoride salt cooled high temperature reactor (KP-FHR) using TRISO fuel in pebble form.

Plant Characteristic Description
Reactor Type Two low-power test reactors to support development of Kairos Power’s fluoride salt-cooled, high-temperature reactor (KP-FHR) technology
Containment Type Functional containment implemented principally by the high temperature TRISO particle fuel. The fuel utilizes a carbon matrix coated fuel particle, similar to that developed for high temperature gas-cooled reactors, in a pebble-based fuel element. (See SECY-18-0096 for a description of functional containment.)
Power Level 35 MWth each unit
Fuel Tri-structural Isotropic (TRISO) fuel particles embedded in a carbon matrix pebble. High Assay Low Enriched Uranium (HALEU)
Balance of Plant Shared steam powered conversion system (Rankine Cycle)

All public documents related to Kairos pre-application activities may be found in ADAMS using the "Advanced Search" tab with a "Document Properties:" selection of Docket Number is equal to 99902069.  All public documents related to the Hermes 2 construction permit application review after acceptance may be found with a selection of Docket Numbers are equal to 05000611 and 0500612. For additional detail, see the following related pages:

Key Milestones Completion Date
Actual - A
Target - T
Application Tendered 07/14/2023 - A
Acceptance Review
Acceptance Review Start 07/17/2023 - A
Docketing Decision Letter Issued/Acceptance Review Complete 09/11/2023 - A
Review Schedule Established/Schedule Letter Issued to Applicant 10/11/2023 - T

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Public Involvement

Date Description
06/28/2023 Public Meeting To Discuss Hermes 2 Pre-Application Engagement and Kairos Power Future Plans

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Contacts for the Kairos Power LLC
Safety Project Managers Michael Orenak

Matthew Hiser

Samuel Cuadrado de Jesus
Environmental Project Managers Peyton Doub

Tamsen Dozier
Public Affairs Officer Scott Burnell

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