Kairos is set apart by its integrated design philosophy, testing program, and licensing approach to deliver its mission of reliable, responsible, and competitive power. The FHR is being designed with characteristics important to our customers: License-ability, constructability, operability, responsibility.
Technology
How it Works
The Kairos Power FHR (KP-FHR) is a novel advanced reactor technology that leverages TRISO fuel in pebble form combined with a low-pressure fluoride salt coolant. The technology uses an efficient and flexible steam cycle to convert heat from fission into electricity and to complement renewable energy sources.
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Coolant
Coolant
Flibe is a molten salt with excellent heat transfer properties and fission product solubility.
Modular Design
Modular Design
The reactor is right-sized for enhanced manufacturability and constructability.
Power Conversion System
Power Conversion System
A high temperature superheated steam cycle produces electricity efficiently, cleanly, and reliably.
Fuel
Fuel
The fuel kernel has its own dual containment within the fuel pebble, creating a defense-in-depth mechanism.
Safety
Safety
The synergy between triso fuel, salt coolant, and passive safety mechanisms create an inherently safe design.
KP-FHR Specifications
POWER OUTPUT |
140 MWE |
NET EFFICIENCY |
45% |
MAIN/ REHEAT TEMPERATURES |
585°C/ 585°C |
MAIN STEAM PRESSURE |
19 MPA |
REACTOR OUTLET TEMPERATURE |
650°C |
REACTOR OPERATING PRESSURE |
NEAR ATMOSPHERIC PRESSURE |
REACTOR STRUCTURAL MATERIAL |
316 STAINLESS STEEL |
FUEL ENRICHMENT LEVEL |
19.75% |
INTERMEDIATE SALT |
"SOLAR" / NITRATE SALT |
REFUELING TYPE |
ONLINE |
DEPLOYMENT CONFIGURATION |
SINGLE / MULTI-MODULE |
BACK-UP POWER SUPPLY |
AUTOMATIC SAFE SHUTDOWN; PASSIVE COOLING UPON LOSS OF POWER |
How We Are Achieving This
Kairos Power has developed a model-to-learn process that supports ongoing planning, designing, building and testing to better enable the transition to clean energy. This agile strategy will reduce costs while allowing Kairos Power to build smarter and faster, developing innovative nuclear technologies to transform the worldwide energy landscape.
Kairos Power's test program enables component development by narrowing the design space through progressive test cycles. Through these accelerated test cycles and applied engineering, teams are empowered to collaborate and learn, building on ongoing achievements. Unique experimental facilities and capabilities support Kairos Power's rapid technology demonstration. The test program also provides validation and qualification data to support the licensing basis for the KP-FHR.
Kairos Power's licensing strategy reduces licensing risk and facilitates licensing certainty for customers via active pre-application engagement with the Nuclear Regulatory Commission (NRC) during the design process prior to plant construction. Licensing process improvements are anticipated by implementation of the Licensing Modernization Project (LMP), which provides a methodology for the identification and focus on safety significant portions of the design and safety analysis during the licensing review. The pre-application engagements further support the focus on key technical and analysis issues and utilize a phased licensing approach, including submission of topical and technical reports and a preliminary safety information document.
Common Questions
How Does Kairos Power's Reactor Differ From The Conventional?
Rather than water, as used in conventional nuclear reactors, the Kairos Power reactor uses molten fluoride salt as a coolant. Molten fluoride salts have excellent chemical stability and tremendous capacity for transferring heat at high temperature and retaining fission products. Various U.S. reactor studies confirm the compatibility of molten fluoride salts with conventional high-temperature structural materials (e.g. stainless steel), thus enabling commercially attractive reliability and service life.
What Fuel Does Kairos Power’s Reactor Use?
Kairos Power’s reactor uses fully ceramic fuel, which maintains structural integrity even at extremely high temperatures. This fuel will be undamaged to well above the melting temperatures of conventional metallic reactor fuels. Proven methods for fabricating and testing these fuels have been demonstrated at U.S. National Laboratories. By using pebble-type fuel, Kairos Power reactors can refuel on line, enabling exceptional reliability and availability.
What Is Fluoride Salt Coolant?
Kairos Power’s reactor uses molten fluoride salt coolant. Molten fluoride salts have outstanding capability to transfer heat at high temperature, excellent chemical stability, and the ability to retain radioactive fission products that might be released from fuel. Extensive experience and design information exists from the early U.S. reactor development program that studied and tested liquid-fueled molten salt reactors. These studies confirmed the compatibility of these salts with Kairos Power’s high-temperature structural materials, enabling commercially attractive reliability and service life.
What Does Kairos Power Mean By Passive Safety?
Passive safety means that Kairos Power reactors do not require electricity to remove heat from the core after shutting down. Kairos Power reactors have uniquely large safety margins based on the selected combination of fuel and coolant, which allows emergency cooling to be driven by fundamental physics rather than engineered systems. In Kairos Power’s reactor, there is no need to provide for make-up coolant (since the coolant cannot boil away), and the fuel tolerance for extremely high temperatures allows orders of magnitude more cooling capability under accident scenarios compared to water-cooled reactors. High-temperature fuel and coolant dramatically simplifies emergency cooling under all conceivable accidents.
What Are The Benefits Of A Low-Pressure Reactor?
The intrinsic low pressure in Kairos Power reactors enhances safety and eliminates the need for bulky and expensive high-pressure containment structures. Kairos Power technology leverages key U.S. federal investments in design, structural materials, and components for low-pressure pool-type reactors, including critical updates to the ASME Boiler and Pressure Vessel Code for design at our service conditions.
Is This A Thorium-Fueled/Fluid-Fueled Reactor?
No. While the use of thorium in a breeding reactor provides potentially attractive benefits, the current challenges with baseload generation do not stem from the price or availability of uranium. Using high-temperature fuels and fluoride salt coolants simplifies licensing, operation, and corrosion control of Kairos Power reactors, while maintaining all relevant safety aspects of molten-salt-fueled reactors.
Is More Detail On The KP-FHR Core Available For Research Purposes?
Yes, the closest comparison to the KP-FHR is with the generic pebble-bed FHR core model (gFHR) which is used for testing purposes and based on previous iterations of pebble-bed reactor technology. The gFHR is not Kairos Power technology. Instead, it functions as a benchmark model for core designers and researchers to better understand the parameters of the KP-FHR.