TerraPower is a nuclear reactor design company founded by Bill Gates in 2015. The company is focused on developing advanced nuclear reactors, specifically the Natrium reactor, which uses molten sodium as a coolant and is designed for enhanced safety and energy storage capabilities. The Natrium reactor is a 345-megawatt design, smaller than traditional reactors but larger than many small modular reactor designs. It is engineered to store excess energy as heat in molten sodium, allowing it to supplement intermittent renewable energy sources like wind and solar. TerraPower received its first permit from the Nuclear Regulatory Commission (NRC) in nearly a decade to build a new reactor in Wyoming, adjacent to an existing coal power plant. The company is backed by significant investment, including from Nvidia, and has raised a total of $1.7 billion.