As a knowledge manager for the 2018 Utility Working Conference, I had many opportunities to interact with nuclear utility leaders. The discussions often centered around finding innovative ways to sustain the existing fleet of nuclear plants by improving plant economics.

To nuclear fuel suppliers, today’s operating reactors represent a defined customer base with predictable demands. Utilities must order their next fuel reload far in advance of an outage; enrichers and fabricators work to fill those orders. Adapting such a highly optimized supply chain to accommodate new products—fuels with new materials, claddings, and higher enrichments and burnups—will require alignment between all parties involved to meet the associated research, enrichment, manufacturing, regulatory, transportation, and operating experience needs.

That was the consensus during “Current Accident Tolerant Fuel Environment,” a technical session held on March 9 during the Nuclear Regulatory Commission's four-day Regulatory Information Conference (RIC, March 8-11). The session was chaired by NRC Chairman Christopher Hanson, who was taking part in his first RIC as a member of the commission.

Image: Purdue University/Maria Okuniewski

A team of researchers led by Purdue University has used X-ray imaging conducted at Argonne National Laboratory’s Advanced Photon Source to obtain a three-dimensional view of the interior of an irradiated nuclear fuel sample. The use of synchrotron micro-computed tomography could lead to more accurate modeling of fuel behavior and more efficient nuclear fuel designs, according to the researchers.

Terrestrial Energy and the Nuclear Research and Consultancy Group (NRG) have started a graphite irradiation testing program at NRG’s Petten Research Centre’s High Flux Reactor (HFR), located in the Netherlands. According to Terrestrial Energy, which is based in Ontario, Canada, the work is part of broader program of confirmatory testing of components and systems for the company’s Integral Molten Salt Reactor (IMSR), designed to produce both electricity and industrial heat.

The testing program at NRG was planned to confirm the predicted performance of selected graphite grades throughout the seven-year cycle of an IMSR core. The testing was designed in cooperation with Frazer-Nash Consultancy, and will simulate IMSR core conditions at a range of operating temperatures and neutron flux conditions.

“Our work with NRG at its Petten HFR facility is an important element of our overall IMSR test program, now well underway. The start of in-core irradiation tests speaks to our progress and comes after many months of prior work,” Simon Irish, CEO of Terrestrial Energy, said on November 12. “The NRG work also reflects an important feature of our testing strategy. That is to engage existing laboratories offering existing capabilities rather than build those in-house, a strategy that is essential for our early deployment schedule.”

Two projects intended to accelerate the deployment of hydrogen production technology at existing U.S. light-water reactors received the bulk of the funding announced by the Department of Energy’s Office of Nuclear Energy (NE) on October 8 under the ongoing U.S. Industry Opportunities for Advanced Nuclear Technology Development funding opportunity announcement (FOA). Out of three projects with a total value of $26.9 million, the two involving hydrogen production have a total value of $26.2 million.

TerraPower announced on September 15 that it plans to work with Centrus Energy to establish commercial-scale production facilities for the high-assay, low-enriched uranium (HALEU) needed to fuel many advanced reactor designs.

The proposed investment in HALEU fuel fabrication is tied to a TerraPower-led submittal to the Department of Energy’s Advanced Reactor Demonstration Program (ARDP), which was created to support the deployment of two first-of-a-kind advanced reactor designs within five to seven years. TerraPower would like one of those designs to be Natrium, the 345-MWe sodium fast reactor that it has developed with GE Hitachi Nuclear Energy.

Idaho National Laboratory’s Transient Reactor Test Facility, also known as TREAT, returned to service in 2017 after a hiatus of more than two decades. To make full use of TREAT’s capabilities, researchers at INL created the Minimal Activation Retrievable Capsule Holder (MARCH) test vehicle system, which, according to an August 26 Department of Energy press release, can cut years off the development process for nuclear fuels and materials and allow new clients, like NASA, to take advantage of TREAT’s capabilities.

Separation of Kr-85 from spent nuclear fuel by a highly selective metal organic framework. Image: Mike Gipple/National Energy Technology Laboratory

According to a story published by the Massachusetts Institute of Technology on July 24, the capture of gaseous fission products such as krypton-85 during the reprocessing of spent nuclear fuel could be aided by the adsorption of gasses into an advanced type of soft crystalline material, metal organic frameworks(MOF), which feature high porosity and large internal surface areas that can trap an array of organic and inorganic compounds.

Uranium producers around the world have suffered through years of record low uranium prices. In 2019 the United States recorded its lowest total uranium production—174,000 lb U3O8—since the U.S. Energy Information Administration began collecting data in 1949, according to the agency’s Today in Energy analysis of July 17.

U.S. uranium producers asked the federal government to come to their aid in January 2018, and President Donald Trump created the U.S. Nuclear Fuel Working Group (NFWG) in July 2019. While the NFWG issued a report in April 2020 recommending support for the front end of the nuclear fuel cycle, uranium producers are in a waiting game once again as the U.S. House of Representatives works on Fiscal Year 2021 appropriations legislation.

BWX Technologies has signed a $26-million, 20-month contract to expand and upgrade its TRISO fuel manufacturing line. The recently announced deal, awarded by Idaho National Laboratory, calls for the expansion of BWXT’s capacity for the manufacture of TRISO fuel compacts and the upgrading of existing systems for delivering production-scale quantities of TRISO fuel.

Now available from the World Nuclear Association is an expanded summary of its latest Nuclear Fuel Report, published last September. According to the WNA, “This expanded summary will provide readers with explanations of what factors are affecting the growth of nuclear power, what new concepts were introduced in the 19th edition, and what developments the industry may require between now and 2040.”

Piercy

Nesbit

ANS Executive Director/CEO Craig Piercy sent a letter to the Nuclear Regulatory Commission on May 28 urging the agency to resume work on a proposed rulemaking to allow spent fuel reprocessing in the United States. As the letter explains, “the lack of an efficient, technically robust, and technology-inclusive regulatory foundation for reprocessing and recycling is a barrier to innovation.”

Steve Nesbit, who was recently elected ANS’s next vice president/president-elect, chairs the ANS Nuclear Waste Policy Task Force and helped develop the letter. ANS News staff talked with Nesbit about the development and goals of ANS’s participation in the NRC’s rulemaking process.

BWX Technologies has announced the successful formation and sintering of uranium oxycarbide (UCO) fuel kernels that, once coated, will make up the fissile core of TRISO (tristructural isotropic) fuel particles. With that process demonstrated, BWXT has shifted the focus of its TRISO production restart to bringing two more furnaces online—an additional sintering furnace, used to apply heat and pressure to a solid fuel kernel, and a coating furnace.

High-assay low-enriched uranium (HALEU) is the fuel of choice for many advanced reactor developers, including Advanced Reactor Concepts, which is designing the ARC-100, a sodium-cooled fast reactor. Developers face a potential supply problem, however: The United States has no clear path to build the commercial HALEU production facilities that would be needed to fuel a fleet of advanced reactors. A letter of intent signed by ARC and Centrus Energy, announced on April 28, calls for cooperation on the deployment of a commercial supply of HALEU and could lead to a HALEU purchase agreement for ARC-100 deployments in the late 2020s.

by Mike Little and Dale Vines, Dominion Engineering, Inc.

Now how did that get there?

Finding foreign material in your reactor system is not the beginning of a good day. Where did it come from? Did someone leave this in here or did something break? When did this happen? These are all good questions for which we need to know the answers.

Vogtle Unit 3 (at left) is scheduled to begin operation in November 2021, one year ahead of Unit 4. Photo: Georgia Power

The Nuclear Regulatory Commission has announced an opportunity to request an adjudicatory hearing regarding Southern Nuclear’s notice of intended operation of Unit 3 at the Vogtle nuclear power plant, located in Waynesboro, Ga. The announcement was prompted by a January 13 letter from Southern Nuclear notifying the NRC of its scheduled date of November 23, 2020, for initial fuel loading at the reactor. As required under 10 CFR 52.103(a), the notification was made more than 270 days prior to the scheduled fuel load.

A combined license was issued for Vogtle-­3 and -­4, Westinghouse-­designed AP1000 pressurized water reactors, in February 2012. The license covers both construction and operation after construction is completed if standards—known as inspections, tests, analyses, and acceptance criteria (ITAAC)—identified in the combined license are satisfied. Operation will not be permitted until the NRC staff finds that all ITAACs have been met. However, if a hearing request is granted, the NRC can allow interim operation, given reasonable assurance of adequate protection of public health and safety while the adjudicatory hearing is carried out.

Advanced reactor cores are being designed for higher efficiencies and longer lifetimes, but to get there, they need high-assay low-enriched uranium (HALEU).

Enriched to between 5 and 19.75 percent fissile U-235, HALEU is packed with nuclear potential. It can be used as a feedstock for the demonstration of new fuel designs, from uranium alloys to ceramic pellets and liquid fuels. Those fuels can enable advanced reactor and microreactor demonstrations. Operating light-water reactors could potentially transition to HALEU uranium oxide fuels for extended operating cycles and improved plant economics.