Idaho project tests the limits of DOE aid to advanced reactors

Does the US need a new multibillion-dollar test facility for developers of advanced nuclear reactors? Should those developers share the cost to build it? Could an advanced commercial reactor that’s slated to be built with $2 billion in taxpayer funding be modified to also provide those testing capabilities?

Those questions have swirled around the Versatile Test Reactor (VTR) that the Department of Energy wants to build at its Idaho National Laboratory (INL). The project was imperiled in July after House and Senate appropriators stiffed DOE’s request for $145 million in fiscal year 2022 funding. Then in September, the House Science, Space, and Technology Committee included $95 million for the VTR in its portion of the $3.5 trillion budget reconciliation package that President Biden and Democratic leaders were hoping to pass without Republican support. As Physics Today went to press, negotiations between the White House and House Democrats were expected to yield a much smaller spending package. If signed into law, funding would bypass the appropriations process and become available immediately. Senate Democrats hadn’t released counterpart legislation.

The VTR snub by appropriators comes after DOE’s Office of Nuclear Energy last year committed more than $5 billion over seven years to its Advanced Reactor Demonstration Program (ARDP), supporting 10 advanced-reactor projects. Each of those employ technologies having coolants other than light water, which is used by all US commercial reactors. The department last year also pledged another $1.3 billion to help finance what is expected to be the first commercial small modular reactor (SMR) deployed in the US (see Physics Today, December 2018, page 26 ).

The ARDP and SMR projects would be fully funded under House and Senate spending bills. Industrial partners would share the cost of them to varying degrees. But DOE maintains that the VTR, as a user facility, should be wholly owned and financed by the government. That has long been the practice for other DOE test reactors, such as the Advanced Test Reactor (ATR) and the Transient Reactor Test Facility, and for the synchrotrons, neutron sources, and other scientific user facilities that the agency has built and operates.

Staff from the House and Senate Appropriations Committees didn’t respond to several requests for comment. But the report accompanying the FY 2021 Senate version of the energy and water development appropriations bill expressed concern that DOE hadn’t obtained commitments from the private sector or foreign governments “for monetary and in-kind contributions” to the VTR. The report instructed the agency to submit by late January a plan for converting the VTR into a public–private partnership. In a 7 October statement to Physics Today, DOE said the plan was still under development and “will address collaborations with industry, such as the VTR/ TerraPower [combination], as one of the methods the VTR will use to establish public–private partnerships to complete this critical piece of nuclear energy research and development infrastructure.”

Congress hadn’t completed action on FY 2022 appropriations as of press time, and federal funding was frozen at FY 2021 levels under a continuing resolution that expires on 3 December. That extension will allow VTR design and preconstruction activities to proceed at last year’s level of effort through the period. DOE plans to formally decide in 2027 whether to build the reactor. Construction is expected to take up to five years.

Look-alikes

Although the VTR would not produce electricity, it would resemble the Natrium, a commercial-scale sodium-cooled fast reactor (SFR) to be built by a partnership of the same name between TerraPower, GE Hitachi Nuclear Energy, and Bechtel. Natrium is one of the two large ARDP projects DOE selected last year to receive $2 billion each over seven years. The other recipient is X Energy, which is to build a four-module high-temperature gas-cooled reactor, the Xe-100. Appropriators okayed DOE’s full FY 2022 requests of $133.6 million for the Natrium and $108.7 million for the Xe-100.

Natrium is not only building its eponymous SFR. Last year DOE selected it through a competitive process to design and build the VTR. But the Natrium SFR is scheduled for completion by 2028, years before the VTR could begin operating. The VTR would borrow many of Natrium’s features, including electromagnetic pumps, intermediate heat exchangers, and sodium and gas cleanup systems, says Kemal Pasamehmetoglu, the VTR project’s executive director at INL. “We are identifying the elements where development benefits both projects and trying not to do them twice,” he says.

A memorandum of understanding signed in June by the lab manager, the Natrium partners, and Acting Assistant Secretary for the Office of Nuclear Energy Kathryn Huff characterizes the technology-sharing arrangement as a public–private partnership. But the agreement specifically excludes any cost sharing.

Pasamehmetoglu says he doesn’t believe commercial developers would help pay for a user facility that would test potentially valuable technologies while being open to all industry players and to academic researchers. Who should decide who should contribute? he asks. “If one company comes in and helps us financially, does that mean that its competitors can’t use the reactor? In my opinion, a test reactor is a government responsibility, just like the other test reactors we have had [at INL].”

As with other DOE user facilities, access to the VTR would be free if the results were made publicly available. The lab would charge for proprietary research. Academic researchers and developers of SFRs and other advanced-reactor types, such as lead cooled and molten salt, could try out new fuels, materials, and instruments and sensors in the VTR’s high-flux and high-energy neutron environment.

In contrast to light-water reactors (LWRs), SFRs operate with unmoderated, high-energy neutrons. Proponents say that, compared with LWRs, such so-called fast reactors offer higher efficiencies, longer stretches between refuelings, and lower costs.

The Natrium SFR will operate initially with fast-reactor technology developed at INL’s Experimental Breeder Reactor-II, an SFR that was shuttered in 1994, says Pasamehmetoglu. But the Natrium partners will benefit in the years ahead from improved fuels and materials to be developed at the VTR, he says. “Natrium’s long-term goal is to go to a very high burnup, long-lasting fuel.”

A tenuous go-ahead

DOE gave a provisional green light to the VTR project in 2020, allowing INL to continue drafting a conceptual design and firming up cost estimates. Currently, the price tag is set in a broad range from $2.6 to $5.8 billion.

DOE solicited expressions of interest from industry for a VTR partnership in 2019. It received four responses in January 2020, including the TerraPower–GE Hitachi proposal. The other respondents, which Pasamehmetoglu declined to identify, “didn’t match what was needed for the VTR,” he says. “We were looking for someone who could design and build it.”

The Natrium SFR and the VTR are to be fueled with metallic fuel. Natrium’s will be high-assay low-enriched uranium (HALEU), which is enriched in the fissile ²³⁵U isotope up to 20%. (Today’s LWRs run on enrichment levels of around 4%.) The VTR’s HALEU will be alloyed with plutonium to increase the neutron flux and to minimize reactor size, says Pasamehmetoglu.

DOE and reactor developers say the US’s lack of a fast-neutron testing capability is slowing the testing of materials and fuels for all types of reactors, including the existing commercial fleet. But should taxpayers fund two nearly identical reactors? No, says Edwin Lyman, director of nuclear power safety at the Union of Concerned Scientists. Converting the Natrium SFR to serve as both a test and a demonstration reactor would save billions, he says. What’s more, DOE-supported graduate students could begin their experiments on the Natrium SFR years sooner than they would if they had to wait for the VTR. Indeed, in 2016, GE Hitachi had proposed building an SFR that would combine testing and electricity-generation functions.

Pasamehmetoglu, however, says the missions of Natrium and the VTR are incompatible. Combining them will result in a less than optimum outcome in meeting the objectives of either mission. He notes that Russia, considered the US’s main rival on fast reactors, recognizes the difference and is constructing a purpose-built test reactor.

In the absence of a US capability, the Bill Gates–founded TerraPower has resorted to Russia for some tests at Rosatom’s BOR-60 fast reactor. Russia also happens to be the world’s sole seller of HALEU. “Russia is happy to be a supplier and make money from it,” says Seth Grae, CEO of Lightbridge, which is designing a HALEU fuel for US commercial reactors. DOE has made small amounts of HALEU available for R&D by diluting its excess highly enriched uranium.

The VTR won’t be of much use to thermal-neutron high-temperature gas-cooled reactors such as X Energy’s Xe-100. But it could help developers of fast-neutron HTGR designs. HTGRs use fuel that’s encapsulated in tens of thousands of graphite-coated and high-heat-resistance pebbles.

Carl Perez, CEO of Elysium Industries, says he supports the VTR even though his company is planning to complete its own prototype molten-salt test reactor by 2028. “Having the government, its employees, and national lab employees work on building a reactor at a national lab will directly help Elysium when we go build a demonstration unit at a national lab,” he says.

But the VTR could be of benefit to more than just nuclear energy, says Jeff Terry, a physicist at the Illinois Institute of Technology. Irradiation studies of materials that would require 10 years to perform at INL’s ATR could be accomplished in three at the VTR, he says. Noting an application further afield, he says, “Some of my colleagues would like to use the VTR for antineutrino research.” As for cost sharing, he notes, “At some point, it’s the government’s job to build tools we can use.”

Today, the ATR is the world’s most powerful test reactor. As an LWR, however, it is of limited value for advanced-reactor hopefuls, and it is largely reserved for the US Navy’s nuclear propulsion reactor program. Though it’s possible to boost the energy level of thermal neutrons, the ATR’s neutron flux is an order of magnitude below the VTR’s design specifications. Such high flux is necessary to accelerate the testing and shorten the development times for fuels and materials.

Still, developers of advanced reactors could meet some of their needs at the ATR if its capacity were increased, says Grae. “For about $30 million, we could triple the capacity [of the ATR] and be more competitive with Russia and China. We’re not doing that, in part because these well-funded advanced-reactor projects are looking for billions, not tens of millions.”

A full plate

Some observers believe that DOE’s nuclear energy office simply has too much on its plate. “The fundamental question is whether there can be enough money in the DOE budget to pursue both the VTR and the ARDP effort at the same time,” says Richard Meserve, a former chair of the Nuclear Regulatory Commission who cochairs DOE’s Nuclear Energy Advisory Committee.

The ARDP also includes funding for five advanced-reactor ventures that the agency said could become commercial within 10–14 years. Those will share $1.2 billion over seven years to further their designs and support licensing activities.

Outside of the ARDP, DOE has committed $1.3 billion to the Carbon Free Power Project, an entity established by a consortium of utilities to build an SMR power plant at INL designed by NuScale Power. Originally proposed as 12 modules with a combined 720 MW of electric capacity, the project was scaled back in July to six units totaling 462 MW. The first module is slated to begin operating in 2029.