Construction Advances for Holtec's SMR-300 Test Facility at Idaho National Laboratory

Holtec International recently announced that construction of its HI-TEST test facility, supporting the SMR-300 small modular reactor, is advancing at Idaho National Laboratory (INL), with manufacturing of key test components and preparation for facility installation already underway. The facility simulates the SMR-300 plant at approximately one-third scale and is designed to quantify reactor design and operational performance margins, providing a test basis for potential future power uprates.

Supported by the U.S. Department of Energy (USDOE), the HI-TEST facility's primary mission is to validate SMR-300 design margins under steady-state and transient conditions, providing physical test data for the plant's power generation capacity, resilience, and operability. Holtec stated that the facility's test program has been expanded beyond the original scope to cover additional system operating modes.

According to Holtec, the SMR-300 is designed based on mature pressurized water reactor technology, with its key components and overall performance previously validated through computational analysis tools. The company has also conducted three-dimensional simulations of the SMR-300 steam generator, covering startup, normal operation, and shutdown conditions, with approximately 80 million simulation data points used to optimize design performance and manufacturability prior to component fabrication.

Holtec adopted a more conservative design approach in the initial licensing phase of the "Pioneer 1" and "Pioneer 2" projects in Michigan. The company hopes to use test data obtained from the HI-TEST facility to support SMR-300 power uprates in the future through license amendment processes.

The SMR-300 is a pressurized water reactor-type small modular reactor with a design electrical output of approximately 300 MWe, and can also provide approximately 1050 MWt for process applications. Holtec plans to deploy two SMR-300 units at the Palisades nuclear plant site in Michigan, named "Pioneer 1" and "Pioneer 2," in partnership with Hyundai Engineering & Construction, with a target of entering operation in the early 2030s. Construction permit applications are currently under review by the U.S. Nuclear Regulatory Commission (NRC), and pre-construction site preparation activities are also underway.