Plans to construct a Natrium reactor demonstration project at a retiring coal plant in Wyoming were announced yesterday by TerraPower and PacifiCorp. The site for the project, which is intended to validate the design, construction and operational features of the Natrium technology, will be selected by the end of 2021.

The Natrium technology developed by TerraPower and GE Hitachi features a 345 MW sodium fast reactor coupled with a molten salt-based integrated energy storage system that will provide clean, flexible energy and stability for the grid. The system can boost output to 500 MW for more than five and a half hours to serve peak demand. The reactor maintains its thermal power constant during its entire operating period, maximizing its capacity factor and value.

Non-nuclear mechanical, electrical and other equipment will be housed in separate structures, reducing complexity and cost. The design is intended to permit significant cost savings by allowing major portions of the plant to be built to industrial standards. Improvements use fewer equipment interfaces and reduce the amount of nuclear-grade concrete by 80% compared to large reactors. Natrium reactors are designed to provide firm, flexible power that seamlessly integrates into power grids with high penetrations of renewables.

Rendering of the future Natrium plant. Source: TerraPower and GE Hitachi Nuclear Energy Americas

TerraPower received $80 million in initial funding in October 2020 from the U.S. Department of Energy through its Advanced Reactor Demonstration Program to demonstrate the Natrium technology. The project is expected to create opportunities for both PacifiCorp and local communities to provide well-paying and long-term jobs for workers in Wyoming communities that have decades of energy expertise.