One of the Tennessee Valley Authority reactors that produces tritium for U.S. nuclear weapons on Tuesday switched off for the scheduled replacement of all four of its steam generators, the federally owned corporation said Wednesday.
Besides replacing the steam generators at Watts Bar Unit 2, workers will “load 88 new nuclear fuel assemblies, perform inspections of reactor components, conduct maintenance of numerous plant equipment, and install additional unit enhancements,” the Tennessee Valley Authority (TVA) wrote in a press release.
In late 2020, Watts Bar 2 started irradiating tritium producing burnable absorber rods for the National Nuclear Security Administration (NNSA), joining Watts Bar 1, which has irradiated tritium since nearly 2003.
The NNSA in January asked TVA to sharply increase the amount of tritium each reactor irradiates. Meanwhile, Watts Bar 2’s first tritium production cycle did not yield exactly the quantity of the radioactive hydrogen isotope that NNSA hoped.
Modern thermonuclear weapons use tritium to increase the efficiency of their nuclear yields, ensuring that the weapons possess their designed destructive power. The NNSA harvest the tritium produced in the TVA reactors at the Savannah River Site in Aiken, S.C. Tritium decays relatively rapidly, meaning the agency must always produce more of it. Westinghouse manufactures the tritium producing burnable absorber rods in South Carolina. The Pacific Northwest National Laboratory designed the rods.