Eventually , more than 120 reactor orders were cancelled , and the construction of new reactors ground to a halt . Al Gore has commented on the historical record and reliability of nuclear power in the United States : Of the 253 nuclear power reactors originally ordered in the United States from 1953 to 2008 , 48 percent were canceled , 11 percent were prematurely shut down , 14 percent experienced at least a one-year-or-more outage , and 27 percent are operating without having a year-plus outage . Thus , only about one fourth of those ordered , or about half of those completed , are still operating and have proved relatively reliable . Amory Lovins has also commented on the historical record of nuclear power in the United States : Of all 132 U.S. nuclear plants built ( 52 % of the 253 originally ordered ) , 21 % were permanently and prematurely closed due to reliability or cost problems , while another 27 % have completely failed for a year or more at least once . The surviving U.S. nuclear plants produce ~ 90 % of their full-time full-load potential , but even they are not fully dependable . Even reliably operating nuclear plants must shut down , on average , for 39 days every 17 months for refueling and maintenance , and unexpected failures do occur too . A cover story in the February 11 , 1985 , issue of '' Forbes magazine '' commented on the overall management of the nuclear power program in the United States : The failure of the U.S. nuclear power program ranks as the largest managerial disaster in business history , a disaster on a monumental scale … only the blind , or the biased , can now think that the money has been well spent . It is a defeat for the U.S. consumer and for the competitiveness of U.S. industry , for the utilities that undertook the program and for the private enterprise system that made it possible . The NRC reported " ( ... the Three Mile Island accident ... ) was the most serious in U.S. commercial nuclear power plant operating history , even though it led to no deaths or injuries to plant workers or members of the nearby community . " The World Nuclear Association reports that " ... more than a dozen major , independent studies have assessed the radiation releases and possible effects on the people and the environment around TMI since the 1979 accident at TMI-2 . The most recent was a 13-year study on 32,000 people . None has found any adverse health effects such as cancers which might be linked to the accident . " Other nuclear power incidents within the US ( defined as safety-related events in civil nuclear power facilities between INES Levels 1 and 3 include those at the Davis-Besse Nuclear Power Plant , which was the source of two of the top five highest conditional core damage frequency nuclear incidents in the United States since 1979 , according to the U.S. Nuclear Regulatory Commission
Three Mile Island accident
Three Mile Island accident
Nuclear power in the United States