U.S. Says Shift to Safer Nuclear Fuel Would Be Costly


January/February 2024 
By Shizuka Kuramitsu

The United States is making progress in developing a safer low-enriched uranium (LEU) fuel for use in Navy ships, but the project is very costly, and success is not assured, according to a report by the National Nuclear Security Administration (NNSA).

The issue of nuclear fuel for navy ships has drawn increased attention since 2021, when the United States and the United Kingdom agreed to sell nuclear-powered submarines to Australia. Australian Prime Minister Anthony Albanese (L), U.S. President Joe Biden (C) and British Prime Minister Rishi Sunak discussed the issue at a press conference in San Diego last March. (Photo by Leon Neal/Getty Images)The United States now relies on highly enriched uranium to provide safe, long-lived, and reliable naval propulsion fuel. But nonproliferation experts have been urging a switch to LEU, which is more difficult to convert for use in nuclear weapons.

In a message accompanying the report, NNSA Administrator Jill Hruby said she was “pleased with the progress…made in this technically challenging effort…[because in] fiscal 2021, we reached a critical milestone” with experiments that will produce the first information evaluating novel fuel-fabrication techniques, as well as fuel performance characteristics.

Nevertheless, the report struck a downbeat tone, concluding that “these initial activities are the first steps on a long, costly path to fuel development and success is not assured.”

It predicted a reactor fuel system design effort lasting 20 to 25 years that would cost more than $1 billion and detract from higher-priority nonproliferation and naval propulsion research and development activities.

“Even if successful, the propulsion system would be less capable, only [be] applicable to aircraft carriers and require several billion dollars, in addition to fuel development costs, to deploy the supporting engineering, manufacturing and testing infrastructure,” the report said.

It added that “the analysis showed that the use of LEU would negatively impact reactor endurance, reactor size, ship costs and operational effectiveness.”But the nonproliferation expert who obtained and publicized the report, which was sent to Congress in 2022 and kept secret until now by the government, argued that the expense for the LEU project should not be questioned. “The program’s price tag is a tiny fraction of the cost of the nuclear Navy or a nuclear terrorist attack,” Alan J. Kuperman, an associate professor at the LBJ School of Public Affairs at the University of Texas at Austin and coordinator of the university’s Nuclear Proliferation Prevention Project, told Reuters.

“These documents clarify three things for the first time: the program is vital to preventing the spread of nuclear weapons, is making rapid progress, and will be implemented only if it can preserve the performance of U.S. Navy vessels,” Kuperman said.

The NNSA has been researching LEU fuel use in Navy systems since 2018 with $50 million appropriated by Congress, but the program is now in doubt after a House subcommittee cut the funding, Reuters reported.

The nuclear fuel issue has drawn increased attention since 2021, when the United States and the United Kingdom raised proliferation concerns by agreeing to sell nuclear-powered submarines to Australia, which would become the first non-nuclear-weapon state to field a ship with an HEU-powered reactor.