New and advanced types of nuclear reactors could play an important role in helping the U.S. meet its long-term climate goals, but a range of technical, regulatory, economic, and societal challenges must first be overcome, says a new report from the National Academies of Sciences, Engineering, and Medicine.New and advanced types of nuclear reactors could play an important role in helping the U.S. meet its long-term climate goals, but a range of technical, regulatory, economic, and societal challenges must first be overcome, says a new report from the National Academies of Sciences, Engineering, and Medicine.