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Antares achieves zero-power criticality at INL
Leveraging more than $140 million in private capital fundraising, over 322,000 square feet of operational manufacturing space, and multifaceted partnerships with the Departments of Energy and Defense, reactor start-up Antares has become the first company involved in the Reactor Pilot Program to achieve zero-power fueled criticality—a full month ahead of the July 4 deadline set by President Trump’s Executive Order 14301.
This milestone, announced yesterday, was achieved with the company’s Mark-0: a sodium heat-pipe-cooled, TRISO-fueled microreactor. The Mark-0 is a forerunner to the company’s flagship design, which it calls the R1. For Antares, this development represents a key validation of its reactor physics, control systems, and supply chain.
S. J. Meitner, L. R. Baylor
Fusion Science and Technology | Volume 79 | Number 8 | November 2023 | Pages 1065-1070
Research Article | doi.org/10.1080/15361055.2023.2174335
Articles are hosted by Taylor and Francis Online.
A continuous pellet fueling system (CPFS) for use on the Wendelstein 7-X (W7-X) stellarator has been fabricated and assembled with commissioning tests completed at the Oak Ridge National Laboratory (ORNL). Continuous fueling is accomplished by cutting pellets from the cross section of a continuous solid extrusion produced by a twin-screw extruder and accelerated by a gas gun cutter mechanism. The pellets travel through a series of straight guide tubes before entering the stellarator through a curved guide tube. The CPFS has an array of diagnostics that include the extruder torque, rotation rate, and thrust. A shock and pressure sensor provide verification of proper pellet cutting and acceleration. Two ORNL-developed microwave cavity diagnostics within the injection line guide tubes provide pellet speed and relative mass measurements. For commissioning, a high-speed camera has been positioned at the base of the extruder to verify extrusion speed and quality as well as the pellet cutting process, and a third microwave cavity has been mounted after the curved guide tube to verify pellet quality and size. Maximum injection rate, pellet speed, barrel and guide tube induced erosion, and pellet survivability data have been recorded. This paper presents the laboratory experimental setup and results of these commissioning tests.