On Wednesday, the United States Nuclear Regulatory Commission (NRC) announced a major decision that has not happened in nearly a decade. The commission officially granted a construction license for a new nuclear power plant. This important ruling clears the path for building to begin at a specific site in Kemmerer, Wyoming. The company leading this large project is TerraPower. It is well known because it received financial support from Bill Gates, the co-founder of Microsoft. However, the company plans to build something very different from the traditional nuclear plants that operate across the nation today.
TerraPower is creating a new type of reactor that changes how nuclear energy works. This design uses liquid sodium to cool the reactor. It also has a built-in system to store energy directly inside the core. While this approval is a big milestone, it does not guarantee the reactor will eventually get permission to operate commercially. It is, however, a critical first step. Without this construction authorization, the entire project could not move forward.
The specific design is called Natrium. It was developed through a joint effort between TerraPower and the major energy company GE Hitachi. This design includes features not widely used in the commercial energy sector before. The most notable feature is using liquid sodium to cool the reactor and transfer heat away from the core. In most traditional nuclear plants, water is the main substance used for cooling. This water must be kept under extremely high pressure to stay liquid at the high temperatures generated by the reactor. High pressure creates big engineering challenges and safety concerns for plant operators. By using liquid sodium instead, the Natrium reactor can circulate its coolant at much lower pressures. This choice avoids many complex problems associated with high-pressure water or steam systems.
However, this innovation comes with its own risks. Sodium is a metal that is highly reactive when it touches air or water. If a leak occurs, the sodium could cause fires or explosions. The company must develop advanced safety systems to manage this risk. Additionally, the Natrium reactor is a fast-neutron reactor. This means it can consume certain radioactive isotopes that would otherwise become long-term waste in traditional designs. This capability could help significantly reduce the amount of hazardous nuclear waste produced by the industry.
The TerraPower reactor is also much smaller than most current nuclear power plants. It has a capacity of 345 megawatts, whereas a typical modern plant produces about 1 gigawatt of electricity. Despite its smaller physical footprint, the plant has a unique energy storage system. Instead of using the heat from the sodium to boil water and spin turbines immediately, the plant will store the heat in a salt-based material. This special salt can hold the heat for later use.
The energy stored in the salt can then be used to generate electricity when it is needed most. This feature allows the plant to operate effectively alongside renewable power sources like wind and solar. Renewable energy sources often produce less power when the wind stops blowing or the sun sets. This inconsistency often causes them to undercut nuclear plants on price in the energy market. However, the Natrium plant can store energy when renewable sources are producing excess power. It can then release that stored energy later to balance the electrical grid.
This storage system will also allow the plant to temporarily output up to 500 megawatts of electricity. This provides a burst of power when demand is high. The ability to shift power production to times of high demand makes this plant a valuable asset for grid stability.