Versatile Test Reactor

The Versatile Test Reactor (VTR) is a project currently in development by the U.S. Department of Energy to build a fast-neutron test reactor by 2026.
History.
After the Fast Flux Test Facility and the Experimental Breeder Reactor-II (EBR-II) were decommissioned in 1992 and 1994, respectively, the United States was left with no fast-neutron reactor in its fleet. Fast-neutron research was limited to a few restricted reactors located in Russia, including the Bor-60. To address this problem Nuclear Energy Innovation Capabilities Act of 2017 included a provision directing the Department of Energy to begin planning for a fast-neutron source. Congress included $35 million in 2018 and $65 million in 2019 in the budget in support of this. In February 2019, VTR cleared Critical Decision 0, demonstrating a mission need requiring investment, the first in a series of project approvals. At that time, Secretary of Energy Rick Perry announced the start of the Versatile Test Reactor Project. In November 2019, Battelle Energy Alliance, the organization that manages Idaho National Laboratory, announced an Expression of Interest (EOI) seeking an industry partner to design and construct the VTR. In January 2020, a collaboration between GE Hitachi Nuclear Energy (GEH) and TerraPower supported by Energy Northwest was announced.
The potential building sites of the VTR being considered are Oak Ridge National Laboratory and Idaho National Laboratory. After a final design has been completed, the decision to build the VTR is expected to be made in 2022.
The Executive Director of the Versatile Test Reactor is Dr. Kemal Pasamehmetoglu.
Conceptual Design.
Four national laboratories, Idaho National Laboratory, Argonne National Lab, Los Alamos National Lab, and Oak Ridge National Laboratory worked with universities and commercial industry to come up with conceptual designs, costs and schedule estimates, and support.
The likely design will be a sodium-cooled 300 megawatt reactor based on GE-Hitachi’s PRISM reactor. The proposed first fuel will utilize a uranium-plutonium-zirconium alloy fuel. Such an alloy fuel was tested previously in the EBR-II reactor. Later reactor fuel could consist of other mixtures and varying enrichments of uranium and plutonium and could use other alloying metals in place of zirconium. There are no power generating facilities planned for the VTR. 
Planned Capabilities.
The Department of Energy Office of Nuclear Energy (NE), Nuclear Energy Advisory Committee (NEAC) report, "Assessment of Missions and Requirements for a New U.S. Test Reactor" recommended the need for a US domestic fast-neutron test capability. The considerations for such a capability include
These planned capabilities are roughly similar to the capabilities of the sodium-cooled fast neutron 400MWth test reactor Fast Flux Test Facility, located at the Hanford Site in the state of Washington, which was decommissioned in 1992.
The preliminary requirements that meet these considerations include:
Uses.
Creating a fast neutron test environment is essential for the development of the next generation of nuclear technologies and reactor designs, many of which rely on fast neutrons to create the sustained chain reaction that generates heat. 
The VTR will be used in the testing of advanced nuclear fuels, materials, instrumentation, and sensors. It will also allow DOE to modernize its essential nuclear energy research and development infrastructure, and conduct crucial advanced technology and materials testing necessary to re-energize the U.S. nuclear energy industry.
Opposition.
Edwin Lyman, senior scientist and acting director of the Nuclear Safety Project at the non-profit Union of Concerned Scientists, questioned the need for a fast-neutron reactor, stating that existing facilities could be utilized to produce fast neutrons.
The breeder design of the reactor produces more fissile material in the form of plutonium, resulting in proliferation fears. 
“There is nothing good about these reactors,” he said. “I think there is a love of plutonium in the [Energy] Department that is irrational.”