Remarkable Safety and Flexibility

Kairos Power’s reactor technology uses a novel combination of existing technologies to achieve new levels of economy, safety, flexibility, modularity and security for nuclear power production. These technology choices were driven by a desire for the Kairos Power design to be economically competitive, safe, and optimized to interface with an increasingly intermittent and unpredictable grid. Kairos Power builds upon major strategic investments that the U.S. Department of Energy has made to support development of advanced reactors.

Questions about Kairos Power’s reactor technology

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.

How is natural gas part of a nuclear reactor? What does this have to do with renewables?

Kairos Power’s reactor uses a nuclear air combined cycle (NACC) to enable highly flexible and responsive electricity generation. Kairos Power’s NACC technology benefits from the large supply chain that exists for natural gas combined cycle plants with unique capabilities afforded by the nuclear heat source. By co-firing with natural gas or hydrogen, Kairos Power’s NACC technology can deliver high-ramp-rate and efficient peaking power to enable high-renewable-energy (thus high-intermittence) grid operation while simultaneously providing clean baseload generation. No existing generating technology can match the combination of efficiency and flexibility that can be achieved with NACC.

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.