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Aalo Atomics achieves criticality on July 4
Executive Order 14301 set an ambitious goal for at least three test reactors to achieve criticality by July 4. Two private companies participating in the Department of Energy’s Reactor Pilot Program—Antares and Valar Atomics—reached this stage earlier in June, and Deployable Energy—participating in the DOE's Nuclear Energy Launch Pad—became the third last week.
In the last few weeks, reports indicated that Aalo would be next, reaching criticality at Idaho National Laboratory with a low-enriched uranium–fueled, sodium-cooled reactor on or near the target date set forth by President Trump’s EO 14301. In the early hours of July 4, Aalo’s critical test reactor—a full-scale zero-power version of its planned 10-MWe Aalo-X—did just that, becoming the fourth DOE-authorized reactor to hit the milestone.
L. P. Leach, L. J. Ybarrondo, G. D. McPherson
Nuclear Technology | Volume 33 | Number 2 | April 1977 | Pages 126-149
Technical Paper | Reactor | doi.org/10.13182/NT77-A31772
Articles are hosted by Taylor and Francis Online.
The first two loss-of-coolant experiments have been performed in the Loss-of-Fluid Test (LOFT) Facility. The experimental results are compared to analytical model results from the RELAP4 computer code. LOFT is a pressurized water reactor specially designed and instrumented to perform experiments representative of a loss-of-coolant accident (LOCA) in a power reactor. For these first two experiments, the nuclear core was not installed in LOFT. The first experiment was initiated from a pressure of 9.3 MPa with water at 282°C, and the break represented a half-size double-ended offset shear in the hot leg of a power reactor. The second experiment was initiated from a pressure of 15.3 MPa, a temperature of 282°C, and simulated a complete double-ended offset shear in the cold leg of a power reactor. In the first experiment, emergency core cooling was injected by low-pressure, high-pressure, and accumulator emergency core cooling systems at times representative of what would occur in a LOCA in a power reactor.