The Department of Energy’s Office of Nuclear Energy is spreading the word about plans to build a tiny microreactor called the Microreactor Applications Research Validation & EvaLuation (MARVEL) project inside Idaho National Laboratory’s Transient Reactor Test (TREAT) Facility and have it in operation within the next three years. INL recently released a video that describes how MARVEL could help researchers and industry partners test, develop, and demonstrate the integration of a microreactor’s heat and electricity output with other technologies.

The future of nuclear technology is bright and affords ample opportunities for today’s students to make an impact. That was the message given by the three plenary panelists on Saturday, April 10, during the final day of the 2021 ANS Virtual Student Conference. The three-day event was hosted by North Carolina State University and had nearly 500 registered attendees.

Registered attendees can view the entire session on demand.

Mary Lou Dunzik-Gougar

Happy spring to you, my nuclear comrades. As I write this column (in early March), I’m glancing out the window at the 10 inches of snow still remaining in my backyard. By the time you read this, the snow may be gone, and spring flowers may be poking out of the earth. Every year, I look forward to gardening season, which is short but fun in Idaho.

Over the past year, unfortunately, many of the things we looked forward to didn’t happen. Hardest hit, of course, were the people who fell ill with COVID-­19 and those who lost jobs. But in the “disappointed” category, our students were especially vulnerable. Elementary school students, who most need face-­to-­face contact with their teachers, were isolated at home. Adolescents and teens had no dances, football games, or lunchtimes with their friends. High school and college seniors couldn’t celebrate graduation. University freshmen, who already cope with significant change and stress, added to their agendas the threat of a global pandemic and the complication of distance learning.

After funding one year of microreactor engineering design work by three teams, the Department of Defense (DOD) announced on March 22 that it has exercised contract options for two of those teams—led by BWXT Advanced Technologies and X-energy—to proceed with development of a final design for a transportable microreactor. Following a final design review in early 2022 and the completion of environmental analysis, one of the two companies may be selected to build a prototype reactor during a 24-­month construction and demonstration phase.

“We are thrilled with the progress our industrial partners have made on their designs,” said Jeff Waksman, Project Pele program manager. “We are confident that by early 2022 we will have two engineering designs matured to a sufficient state that we will be able to determine suitability for possible construction and testing.”

In response to House Democrats’ introduction on March 2 of a massive energy bill, the CLEAN Future Act, Republicans on the House Energy and Commerce Committee have unveiled their own, more modest energy agenda—a package of existing legislation that they say would “secure America’s energy future and global competitive edge against China.”

McMorris Rodgers

According to a March 15 press release from the committee’s ranking member, Rep. Cathy McMorris Rodgers (R., Wash.), along with Reps. Fred Upton (R., Mich.) and David McKinley (R., W.Va.), the GOP plan will address climate change risks and spur the development and deployment of clean energy infrastructure without the “pie-in-the-sky” mandates, regulations, and federal government spending advocated by the Democrats.

What they’re saying: “This package will modernize and improve our energy infrastructure and promote an all-of-the-above energy strategy across the board, including solutions to unleash innovation in hydropower, nuclear, clean coal, and natural gas,” the Republican lawmakers state. “These are real, workable solutions to make energy cleaner, reduce emissions, prioritize energy security, and keep energy costs low.”

The Nuclear Regulatory Commission has opened registration for its annual Regulatory Information Conference (RIC), the largest public meeting the agency hosts. Scheduled for March 8–11, the 33rd RIC will be an all-virtual event.

The full conference program and registration information can be accessed from the RIC Web page.

Details: In addition to remarks from the NRC commissioners and the executive director of operations, RIC 2021 will feature two special plenary sessions, including one in recognition of the 10th anniversary of the Fukushima Daiichi accident, and 28 technical sessions covering a wide range of topics, such as advanced reactors, accident tolerant fuel, artificial intelligence, cybersecurity, microreactors, and risk-informed decision making.

A hot fire test of the core stage for NASA’s Space Launch System rocket at Stennis Space Center in Mississippi was not completed as planned. The SLS is the vehicle meant to propel a crewed mission to the moon in 2024. Source: NASA Television

Among the executive orders President Trump issued during his last weeks in office was “Promoting Small Modular Reactors for National Defense and Space Exploration,” which builds on the Space Policy Directives published during his term. The order, issued on January 12, calls for actions within the next six months by NASA and the Department of Defense (DOD), together with the Department of Energy and other federal entities. Whether the Biden administration will retain some, all, or none of the specific goals of the Trump administration’s space nuclear policy remains to be seen, but one thing is very clear: If deep space exploration remains a priority, nuclear-powered and -propelled spacecraft will be needed.

The prospects for near-term deployment of nuclear propulsion and power systems in space improved during Trump’s presidency. However, Trump left office days after a hot fire test of NASA’s Space Launch System (SLS) rocket did not go as planned. The SLS rocket is meant to propel crewed missions to the moon in 2024 and to enable a series of long-duration lunar missions that could be powered by small lunar reactor installations. The test on January 16 of four engines that were supposed to fire for over eight minutes was automatically aborted after one minute, casting some doubt that a planned November 2021 Artemis I mission can go ahead on schedule.

The Department of Energy launched a 14-day public review and comment period on January 11 on a draft environmental assessment for a proposal to construct the Microreactor Applications Research Validation & EvaLuation (MARVEL) project microreactor inside Idaho National Laboratory’s Transient Reactor Test (TREAT) Facility.

The basics: The MARVEL design is a sodium-potassium–cooled thermal microreactor fueled by uranium zirconium hydride fuel pins using high-assay, low-enriched uranium (HALEU). It would be a 100-kWt reactor capable of generating about 20 kWe using Stirling engines over a core life of about two years.

The DOE proposes to install the MARVEL microreactor in a concrete storage pit in the north high bay of the TREAT reactor building. Modifications to the building to accommodate MARVEL are anticipated to take five to seven months. Constructing, assembling, and performing preoperational testing are expected to take another two to three months prior to fuel loading.

“Advanced Nuclear Reactors and Power Systems-I” on November 18 during the 2020 ANS Virtual Winter Meeting was the first of a three-session set examining the status of various advanced reactors. The sessions were sponsored by the Operations and Power Division and chaired by Piyush Sabharwall of Idaho National Laboratory.

Presentation topics in the first session included the core design and helium Brayton cycle design of the Holos-Quad microreactor, a microreactor design for a truck charging station, and a levelized cost of electricity (LCOE) estimation on HALEU (high-assay low-enriched uranium) fuels for small modular reactors.

Here are some highlights:

Fabricated yttrium hydride samples are pulled out of the system. Photo: ORNL

Oak Ridge National Laboratory scientists have developed a method to produce solid yttrium hydride for use as a moderator for the Transformational Challenge Reactor (TCR), a 3-MWt additively manufactured microreactor that ORNL aims to demonstrate by 2023. Lacking a commercial supply of the metal hydride, ORNL scientists developed a system to produce yttrium hydride in large quantities and to exacting standards.

The hydrogen density and moderating efficiency of metal hydrides—which combine a rare earth metal with hydrogen—could enable smaller reactor cores that can operate more efficiently and reduce waste products, according to ORNL. The material could be used in other advanced reactor designs, including space power and propulsion systems for NASA, and has been proposed as a shield component for thermalization and neutron absorption in fast-spectrum nuclear reactors.

The MiFi-DC as portrayed in a video released by Argonne.

Electrifying the nation’s trucking industry could reduce consumption of fossil-based diesel fuel, but it would also pose new challenges. A cross-country 18-wheel truck needs five to 10 times more electricity than an electric car to recharge its battery. Where will that electricity come from?

A team of engineers at Argonne National Laboratory has designed a microreactor called the MiFi-DC (for MicroFission Direct Current) that they say could be mass-produced and installed at highway rest stops to power a future fleet of electric 18-wheelers.

Nuclear News reached out to the MiFi-DC team to learn more. The team, led by Derek Kultgen, a principal engineer at Argonne who also leads the lab’s Mechanisms Engineering Test Loop, responded to questions by email. While they emphasized that much more needs to be done before the MiFi-DC could become a fixture at rest stops across the country, the information the team shared sheds some light on the process of designing a tiny reactor for a specific purpose.

A team of engineers in Argonne National Laboratory’s Nuclear Science and Engineering Division have designed a microreactor called MiFi-DC that could be factory-produced and installed at highway rest stops across the country to power a proposed fleet of electric trucks. The reactors are described in an article, Could Argonne’s mini nuclear reactor solve the e-truck recharging dilemma? and a video released by Argonne on October 6.

Pairing a liquid metal thermal reactor with a thermal energy storage system, each reactor could fuel an average of 17 trucks a day.

The Nuclear Regulatory Commission has announced a notice of opportunity to intervene in an adjudicatory hearing on Oklo Power’s combined license application (COLA) for construction of a microreactor at Idaho National Laboratory. The notice, dated June 24, was published in the Federal Register on June 30, opening a 60-day window for petitions.

The U.S. International Development Finance Corporation (DFC) has initiated a 30-day public notice and comment period on a proposed change to the agency’s Environmental and Social Policy and Procedures that would allow it to consider support for nuclear power projects, according to a June 10 press release. Currently, DFC is specifically prohibited from offering support for such projects.

The Nuclear Regulatory Commission is developing a generic environmental impact statement (GEIS) for small-scale advanced reactor designs. Just how small a reactor must be to fit the parameters of the GEIS is one topic open for public comment, but the NRC staff anticipates including reactors generating up to 30 MWt. The public comment period is open until June 30

Three reactor developers got a boost on March 9 when they were each awarded a contract from the U.S. Department of Defense (DOD) to design a reactor that can fit inside a standard shipping container for military deployment. The DOD’s Strategic Capabilities Office (SCO), in partnership with the Department of Energy, proposes to build and demonstrate a 1–10 MWe reactor within four years that, if successful, could be widely deployed to support the DOD’s domestic and operational energy demands.

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.