US companies Ultra Safe Nuclear Corp. (USNC) and Peregrine Turbine Technologies (PTT) are to collaborate with the aim of integrating USNC’s Pylon reactor with PTT’s patented supercritical CO2 (sCO2) energy conversion system and advanced heat exchanger technologies. This partnership “focuses on enhancing clean energy generation through advanced nuclear and turbine technologies”.
The Pylon reactor, developed by USNC, is a compact nuclear reactor designed to provide 1-5 MWt of power for up to three years. It can be integrated with modular balance of plants tailored to specific applications including remote terrestrial, marine, and space deployments. In 2024, USNC was selected for the National Reactor Innovation Center (NRIC) Front End Engineering programme as a step toward demonstrating the Pylon reactor at the DOME (Demonstration and Operation of Microreactor Experiments) test bed at Idaho National Laboratory (INL) by 2027.
PTT’s energy conversion system, developed and demonstrated in collaboration with Sandia National Laboratories’ Brayton Laboratory, is tailored for advanced nuclear reactors. It offers enhanced efficiency compared with traditional steam and Air Brayton conversion systems.
USNC is working with NASA and the US Defense Department on advanced radioisotope power, nuclear thermal propulsion systems and advanced materials using the same strict inherent and intrinsic safety principles to drive innovation in fuels, materials, and design. Its Micro Modular Reactor (MMR) high-temperature gas-cooled reactor (HTGR) system is being licensed in Canada and the US. USNC says demonstration units are scheduled for first nuclear power in 2026. USNC is also the only private company producing Tri-structural Isotropic (TRISO) fuel and Fully Ceramic Micro-encapsulated Fuel (FMC).
Pylon builds on the expertise of the MMR and FCM fuel technologies. The Pylon architecture is a commercially viable fission power system designed for safely generating electrical and thermal power anywhere. Compared with the MMR, Pylon is a lower mass system that is more easily transportable to off-grid locations and space.
The Pylon D1 Demonstration System, scheduled for testing at DOME, incorporates a compact HTGR that employs FCM nuclear fuel, a metal hydride neutron moderator, and graphite control drums. The system uses helium to transport heat generated by nuclear fission away from the reactor through a primary coolant loop. This heat is then transferred to a secondary gas loop, which could involve various gases like helium, air, or supercritical CO2 (currently being evaluated for optimal performance), ultimately dissipating the heat into the ambient surroundings.
In July 2023, PTT established a new subsidiary, PTT Nuclear Energy Systems, after it had "identified significant potential and opportunity for its breakthrough energy conversion technologies in the accelerating VSMR (very small modular reactor) and MMR (micro modular reactor) programmes. PTT said it was "working to field a family of its proprietary modular sCO2 energy conversions systems with initial capabilities ranging from 350kW to 10 MW".
"This collaboration represents a shared commitment to advancing nuclear technology and turbine systems for cleaner energy production," the partners said in a joint statement. "By combining USNC's innovative reactor design with PTT's world-record energy conversion efficiency, the partnership will result in a transformative reliable and scalable clean energy solutions."
Image courtesy of USNC
