Fuels of the future

At Los Alamos National Laboratory, construction is underway on an advanced nuclear-reactor fuels manufacturing hub. The Low-Enriched Fuel Fabrication Facility (LEFFF) is expected to be fully operational by 2026. 

LEFFF will make a variety of fuel types, collaborating with partners ranging from small businesses to Fortune 500 companies, the Department of Energy, the National Aeronautics and Space Administration, and the National Criticality Research Center. “We will be a national tool to facilitate the maturation of new fuels,” says Tim Coons, LEFFF team leader.

Why this need for different fuels? It stems from the development of prototype nuclear reactors that require small fuel amounts to achieve proof of performance. 

Scientists are developing advanced reactor designs that have the potential to improve the safety and operation of nuclear plants. Each new reactor design can require a slightly different fuel formulation. The new reactor designs are advanced, but so are the fuels. These fuels can be more resistant to radiation, corrosion, or high temperatures.

“LEFFF will bridge the gap between research and development and commercial production,” Coons says. “The facility will serve as a launching pad for these advanced reactor companies to move to the commercial stage of reactor development.” 

Nuclear reactors operate by splitting atoms (nuclear fission) to produce heat. That heat generates steam, which then spins a turbine. The turbine is connected to an alternator that releases energy. The initial energy to split atoms comes from the reactor fuel, which generally consists of uranium processed into small ceramic pellets and stacked together in sealed metal tubes called fuel rods. Typically, more than 200 of these rods are bundled together to form a fuel assembly.

One of the advantages of LEFFF will be its ability to use low-enriched uranium for fuel fabrication, including high-assay, low-enriched uranium (HALEU), which contains an increased concentration of uranium-235 (the fissile uranium isotope). Using HALEU to manufacture novel fuels allows researchers to design new types of reactors that can operate for decades without refueling, which increases safety and reduces waste. Currently, Los Alamos National Laboratory is one of the few places in the country with the ability and authority to work with HALEU, which is produced in limited quantities and requires a high level of expertise, safety training, and special authorization to use. “This  will be a major advantage for the customers that partner with LEFFF,” Coons says.

Coons says LEFFF will draw upon Los Alamos and Department of Energy expertise to ensure all safety measures are in place and approvals documents are implemented. This facility will also be included in the Lab’s new Site-Wide Environmental Impact Statement, and the general public will be able to comment on the facility’s environmental impact.

Coons describes LEFFF as agile. “This is an intermediate place where we want to fail fast and learn what the challenges are,” he says. He points out that LEFFF will be flexible and multidisciplinary. “Partners both large and small need this fuel fabrication facility.” 

When complete, LEFFF will contain equipment for chemical testing and processing of fuels; mechanical pressing and machining; high-temperature processing; and analysis, characterization, and qualification of fuels. The goal is to fabricate around 200 kilograms of fuel per year, Coons says. “The main mission is to take an advanced concept and run it through its paces before going into full production,” he notes. “That way you actually learn the process and determine if it makes business sense or if anything needs to be changed.” 

LEFFF will work with one customer at a time, targeting the customer’s demonstration of technology and requirements. The 3,500-square-foot facility will also conduct research to assist the Lab’s nuclear nonproliferation teams to improve their ability to detect signatures from fuel fabrication facilities.   

“When LEFFF is finished, it will be an adaptable radiological facility that will allow us to do a variety of things that serve the Lab’s mission,” Coon’s says.  “Los Alamos is the place to take an advanced manufacturing concept and run with it. We embrace challenges. Making a safe, deployable, and reliable energy source is the type of extreme challenge this Lab was made for.” ★