Next-generation nuclear reactors are fuelling debate over whether their fuel could be used to make bombs, jeopardising efforts to prevent the proliferation of nuclear weapons.
The uranium present in the fuel could theoretically be used to develop a nuclear weapon. Older reactors use such low concentrations. They do not actually pose a threat to weapons proliferation, but advanced reactors would use higher concentrations, making them a potential target for terrorist groups or other countries looking to use the fuel to develop their own nuclear weapons, some experts warn.
They argue that the United States has not sufficiently prepared to protect against such a worst-case scenario and are calling on Congress and the Department of Energy to assess the potential safety risks posed by fuel for advanced reactors.
Some experts argue that the United States has not prepared enough to protect itself against such a worst-case scenario.
Other experts and industry groups still think such a dire scenario is unlikely to materialize, but the issue is starting to gain prominence as nuclear reactors become a more attractive source of energy, generating a rare show of bipartisan support in Congress.
Nuclear reactors generate electricity without producing greenhouse gas emissions that cause climate change. And unlike solar and wind power, which fluctuate with the weather and time of day, nuclear reactors provide a steady source of electricity similar to gas and coal-fired power plants. Earlier this month, President Joe Biden Signed a bipartisan law The goal is to accelerate the development of next-generation nuclear reactors in the United States by streamlining the approval process.
Next-generation reactors are smaller and more modular, making them cheaper and easier to build than traditional nuclear power plants. In addition to generating electricity, small reactor designs could also be used to produce high temperature heat x-energy-build-us-gulf-coast-nuclear-demonstration-plant-2023-03-01/”>for industrial installations.
Last year, the U.S. Nuclear Regulatory Commission (NRC) certified the design of an advanced, small, modular reactor for the first time. And commercial plants are likely still years away from being up and running. But if the U.S. wants to get to that point, it will also need to build a supply chain for the fuel those advanced reactors would consume. The Inflation Reduction Act includes 700 million dollars to develop that internal fuel supply.
Current reactors typically run on fuel made from a uranium isotope called U-235. Natural uranium has fairly low concentrations of U-235; it must be “enriched,” typically to a 5 percent U-235 concentration for a traditional reactor. Smaller, more advanced reactors would run on higher energy-density fuel enriched with 5 to 20 percent U-235, called LEAVE (short for low-enriched, high-assay uranium).
That increased concentration is what worries some experts. “If HALEU is confirmed to be weapons-grade, then even a single reactor would pose serious safety concerns,” says one expert. policy analysis written by a group of experts and engineers in nuclear proliferation published in the journal Science last month (including an author He is credited with being one of the architects of the first hydrogen bomb.
Fuel with a concentration of at least 20 percent is considered highly enriched uranium, which could potentially be used to develop nuclear weapons. With HALEU designs reaching 19.75 percent U-235, the authors argue, it is time for the United States to think seriously about how secure the next generation of nuclear reactors would be against malicious intent.
“We need to make sure we're not getting ahead of ourselves and that all the safety precautions are in place before we start shipping (HALEU) around the country,” said R. Scott Kemp, associate professor of nuclear science and engineering and director of MIT's Nuclear Security and Policy Laboratory.
That 20 percent threshold dates back to the 1970s, and malicious actors apparently have more information and computational tools at their disposal to develop weapons, Kemp and his co-authors write in the paper. It might even be possible to make a bomb with HALEU well below the 20 percent threshold, the paper argues.
“This is not a petty theft.”
Fortunately, that would be incredibly difficult to do. “This is not a petty theft,” says Charles Forsberg, a senior research scientist at MIT and formerly a corporate fellow at Oak Ridge National Laboratory. A group might have to steal a couple of years’ worth of fuel from a small, advanced reactor to make the kind of bomb described in the paper, he says.
Even with a working weapons design, he says it would take a sophisticated team of at least several hundred people to perform all the steps required to convert that fuel into uranium metal for a viable weapon. “Unless they are much better than me and the colleagues I work with, a subnational group (such as a terrorist group) doesn’t stand a chance,” he says. The edge.
An adversary nation would have more capability than a small group, but they still don't think it's worth it to them. With their resources, they could go ahead and build a plant to produce weapons-grade uranium, typically enriched above 90 percent in U-235.
A more credible risk, he says, would be another country starting to produce and stockpile HALEU for future reactors, but they actually have more nefarious intentions in mind. Once they’re enriching uranium for HALEU, they’ve already begun ramping up their capacity to reach weapons-grade uranium. “That’s the concern we have with any nation-state that decides to produce HALEU,” Forsberg says. “They’ve taken some of the steps … they’re getting closer to the finish line.”
In addition to calling on Congress to provide an updated safety assessment of HALEU, the document suggests setting a lower uranium enrichment limit based on new research or strengthening safety measures for HALEU to be closer to those for weapons-usable fuels.
Unlike the authors of the Science In his article, Forsberg believes that adequate precautions have already been taken to keep next-generation nuclear reactors and HALEU safe in the United States. The safety risks have been known and discussed for decades, he says, although much of that information is classified. That's part of what makes it difficult to calm fears.
“The opinions of the authors of this study do not present any new information that should discourage the development and implementation of HALEU in accordance with the already stringent requirements set by U.S. and international regulatory bodies,” Jennifer Uhle, vice president of technical and regulatory services at the Nuclear Energy Institute, said in an emailed statement to The edge.
Some of the fears surrounding nuclear power following the disasters at Chernobyl in 1986 and Fukushima in 2011 have been allayed by the need to find energy sources that do not contribute to climate change and the promise of more advanced technologies. But not everyone is convinced, and the safety concerns raised by the HALEU project coincide with other questions that critics raise about nuclear power.
“Unless there is a very good reason to switch to fuels that pose greater nuclear proliferation risks, then it is irresponsible to do so,” says Edwin Lyman, director of nuclear energy safety at the Union of Concerned Scientists and another author of the paper. Lyman has also raised concerns on radioactive waste from nuclear reactors over the years. “There is no good reason.”
