TerraPower's Michael Anderson, manager of test engineers and technicians, talks about the large periodic table on the wall overhead during a tour of the nuclear reactor development facility, Thursday, Jan. 13, 2022, in Everett, Wash. TerraPower plans to make its plant useful for today's energy grid with ever more renewable power. A salt heat "battery" will allow a nuclear plant to ramp up electricity production on demand, offsetting dips in electricity when the wind isn't blowing and sun isn't shining. (AP Photo/Elaine Thompson)