Investopedia: The Biggest Nuclear Operators In The United States

There is no question that the disaster in Japan has refocused investor attention on nuclear power's future both abroad and in the United States. Although it is true that nuclear power is not nearly as important to the U.S. power infrastructure as it is in some countries (notably France, Belgium, Sweden, Germany and Japan), it is more pervasive than some investors may realize. 

More to the point, while there is a wide range of company-level exposure to nuclear power, the reality is that a very large percentage of U.S. utilities have some level of exposure. Given the difficulties of decommissioning nuclear facilities and the trouble of installing alternate capacity, this is unlikely to change.
Nevertheless, investors may find it helpful to keep a cheat-sheet on the exposure levels of major U.S. utilities. Please note that the following tables to include somewhat arbitrary distinctions between "regulated" and "diversified" and that the numbers do not include power purchased under long-term contracts (which can be significant for some utilities). 


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