The Fuel Grade for Next-Gen Nuclear Propulsion is Only Made in Russia
With emissions targets looming, shipping is looking at the full scope of non-fossil alternatives for propulsion, and even revisiting the Cold War-era vision of nuclear-powered merchant ships. There are plenty of well-explored challenges, but there is one issue that has been little discussed: the kind of fuel that most new reactor designs need is only sold by the Russian government.
(Most) reactors need uranium, but only about 0.7 percent of the uranium found in the ground is U-235, the isotope needed for nuclear fission. Raw uranium has to be concentrated - enriched - for use. Enrichment to 3-5 percent is standard for commercial nuclear reactors, and this everyday product goes by the name "low-enriched uranium" or LEU.
More concentrated formulations of 5-20 percent are used in small quantities for research, and this category is known in the trade as "high assay low enriched uranium," or HALEU.
Virtually all of the small, modern reactor designs under development today are built around the availability of HALEU. There is a good reason: a more concentrated fuel means more power and longer life out of the same package. But the nuclear industry says that there is a serious supply chain vulnerability for HALEU, and that vulnerability has come up in stark relief because of the Russian invasion of Ukraine. There is only one commercial seller who makes HALEU: Russian state nuclear energy company Rosatom.
Rosatom is a vendor for civilian nuclear power operators around the world, and it has not yet been sanctioned in connection with the war. But the risks of doing business with a Russian sole supplier turned out to be too much for one of the leading developers of modern reactor technology. U.S.-based nuclear company TerraPower, which is working with the U.S. Department of Energy on a demonstration-scale molten salt reactor, announced this week that it will be delaying project startup by two years because of the limited availability of HALEU.
"Russia’s invasion of Ukraine caused the only commercial source of HALEU fuel to no longer be a viable part of the supply chain for TerraPower, as well as for others in our industry," president and CEO Chris Levesque said in a statement Tuesday. "It has become clear that domestic and allied HALEU manufacturing options will not reach commercial capacity in time to meet the proposed 2028 in-service date for the . . . demonstration plant."
Almost all of the molten-salt reactor designs that have been proposed for maritime applications also rely on a supply of HALEU. Because of their power density and long life, molten salt reactors are seen as a key technology for commercializing nuclear power on the water - both in the engine room and in "power barge" floating power station concepts. (One conceptual alternative, the thorium-based molten salt reactor, would need no uranium.)
In theory, the HALEU supply chain problem is readily fixable. To make the fuel, the uranium feedstock can just be enriched further using the same type of equipment needed for making LEU. HALEU can also be produced by de-enriching defense stockpiles of weapons-grade uranium or naval reactor fuel.
The problem is a classic chicken or egg proposition, according to the nuclear industry. HALEU is tightly regulated for security reasons and would require a secure new plant to handle. U.S. fuel makers don't want to invest in a new plant without someone to buy the product, and at present, the reactors that would use HALEU have not been built.
“It would be a significant business risk to invest the money to make HALEU if there weren’t customers to take it in the long-term,” Kirk Schnoebelen, head of sales at uranium manufacturer Urenco told Utility Dive.
TerraPower has called on Congress to invest more than $2 billion in solving this problem, with support from elected officials. Senator John Barrasso (R-WY) has called for federal funding, and he has pointedly criticized the Department of Energy for not taking action to make HALEU available from government stockpiles for initial testing.
"TerraPower’s announcement underscores what I’ve been saying for years: America must reestablish itself as the global leader in nuclear energy. Instead of relying on our adversaries like Russia for uranium, the United States must produce its own supply of advanced nuclear fuel," said Sen. Barrasso in a statement.