Continued development of new nuclear reactor technologies will expand access to reliable, clean energy all over the world. Many U.S. vendors are planning to demonstrate reactor technology innovations within the decade, but to advance faster and improve upon these designs over time, the infrastructure to support their development and commercial deployment is needed. Acknowledging the role of nuclear power providing a secure and environmentally sound energy supply, U.S. Department of Energy (DOE) experts underscore the importance of both reactor demonstration and new test reactor programs.

Many of the advanced reactors in the demonstration pipeline incorporate innovative fuels, materials and technologies into modern concepts that build upon more than 50 reactor demonstrations at U.S. national laboratories. The Advanced Test Reactor (ATR) at U.S. Idaho National Laboratory is the world’s premier thermal neutron test reactor and enables nuclear fuel and materials testing for military, federal, university and industry partners. However, ATR and other DOE test reactors are not capable of sustaining neutrons at concentrations and speeds high enough to perform accelerated testing of innovative nuclear technologies. Faster testing is warranted to evaluate multiple ideas quickly and make refinements that yield innovations to support the safer and more economical operation of nuclear power plants.

To that end, the agency is designing the Versatile Test Reactor (VTR) to provide a high flux, fast neutron environment to support accelerated fuels and materials experiments over the next 60 years. The VTR is based on a sodium-cooled reactor design and will use high-performance fuel with 100-day operating cycles, followed by a 20-day outage to refuel and replace experiments.

With four cartridge test loops, a rapid-shuttle test loop, multiple positions for standard tests and possible insertion of dismountable test elements in any of the fuel positions in the reactor core, VTR will be able to run several types of tests simultaneously, including experiments for molten salt, sodium-cooled fast, lead-cooled fast and gas-cooled fast reactors. If final design and construction begin in 2023, VTR will be fully operational by the end of 2026, pending funding appropriations by Congress. Potential locations are being scouted at U.S. Idaho National Laboratory and U.S. Oak Ridge National Laboratory.

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