Chris Levesque, president and CEO of TerraPower, a company developing and building small nuclear reactors, displays a fuel assembly model, Thursday, Jan. 13, 2022, in Everett, Wash. The 5-foot model is about one-third actual length and would be vertical when in use, rather than horizontal. By cooling the reactor with liquid sodium, a metal that solidifies at well above room temperature, TerraPower says its relatively small, 345-megawatt plant will be safe and less expensive than conventional, water-cooled nuclear plants. (AP Photo/Elaine Thompson)

Molten sodium sits in a beaker atop a hot plate as part of a demonstration at TerraPower, a company developing and building small nuclear reactors, Thursday, Jan. 13, 2022, in Everett, Wash. Bill Gates, the man who revolutionized personal computing, is launching an ambitious project to counter climate change: A nationwide reboot of nuclear energy technology. In November, Gates' company TerraPower announced it had chosen Kemmerer, Wy., for a nontraditional, sodium-cooled nuclear reactor that will bring on workers from a local coal-fired power plant scheduled to close soon. The project comes as many U.S. states see nuclear emerging as an answer to fill the gap as a transition away from coal, oil and natural gas to reduce greenhouse gas emissions. (AP Photo/Elaine Thompson)

Test engineer Jacob Wilcox pulls his arm out of a glove box used for processing sodium at TerraPower, a company developing and building small nuclear reactors, Thursday, Jan. 13, 2022, in Everett, Wash. In November, Bill Gates' company TerraPower announced it had chosen Kemmerer, Wy., for a nontraditional, sodium-cooled nuclear reactor that will bring on workers from a local coal-fired power plant scheduled to close soon. The project comes as many U.S. states see nuclear emerging as an answer to fill the gap as a transition away from coal, oil and natural gas to reduce greenhouse gas emissions. (AP Photo/Elaine Thompson)

FILE - Steel and concrete containers used for dry storage of spent fuel at the Tennessee Valley Authority's Sequoyah nuclear plant near Chattanooga, Tenn., are shown to the media during a Friday Jan. 13, 2012 tour. As climate change pushes states in the U.S. to dramatically cut their use of fossil fuels, many are coming to the conclusion that solar, wind and other renewable power sources won't be enough to keep the lights on. Nuclear power is emerging as an answer to fill the gap as states transition away from coal, oil and natural gas to reduce greenhouse gas emissions and stave off the worst effects of a warming planet. (AP Photo/ Bill Poovey, File)

FILE - One of Pacific Gas and Electric's Diablo Canyon Power Plant's nuclear reactors is photographed on Nov. 3, 2008, in Avila Beach, Calif. As climate change pushes states in the U.S. to dramatically cut their use of fossil fuels, many are coming to the conclusion that solar, wind and other renewable power sources won't be enough to keep the lights on. Nuclear power is emerging as an answer to fill the gap as states transition away from coal, oil and natural gas to reduce greenhouse gas emissions and stave off the worst effects of a warming planet. (AP Photo/Michael A. Mariant, File)

FILE - Peter Galbraith displays his opposition to a proposal to waive an environmental review of the Diablo Canyon Nuclear Power plant before renewing the plant's license, Tuesday, June 28, 2016, in Sacramento, Calif. As climate change pushes states in the U.S. to dramatically cut their use of fossil fuels, many are coming to the conclusion that solar, wind and other renewable power sources won't be enough to keep the lights on. Nuclear power is emerging as an answer to fill the gap as states transition away from coal, oil and natural gas to reduce greenhouse gas emissions and stave off the worst effects of a warming planet. (AP Photo/Rich Pedroncelli, File)

FILE - Framed by the Manhattan skyline electricians with IBEW Local 3 install solar panels on top of the Terminal B garage at LaGuardia Airport, Tuesday, Nov. 9, 2021, in the Queens borough of New York. As climate change pushes states in the U.S. to dramatically cut their use of fossil fuels, many are coming to the conclusion that solar, wind and other renewable power sources won't be enough to keep the lights on. Nuclear power is emerging as an answer to fill the gap as states transition away from coal, oil and natural gas to reduce greenhouse gas emissions and stave off the worst effects of a warming planet. (AP Photo/Mary Altaffer, File)

FILE - Three of Deepwater Wind's five turbines stand in the water off Block Island, R.I, the nation's first offshore wind farm on Aug. 15, 2016. As climate change pushes states in the U.S. to dramatically cut their use of fossil fuels, many are coming to the conclusion that solar, wind and other renewable power sources won't be enough to keep the lights on. Nuclear power is emerging as an answer to fill the gap as states transition away from coal, oil and natural gas to reduce greenhouse gas emissions and stave off the worst effects of a warming planet. (AP Photo/Michael Dwyer, File)

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)