(This Sept. 23 story has been corrected to say that Unit 1 was shut down due to 'economic reasons,' not 'operational issues,' in paragraph 4) (Reuters) - Microsoft is estimated to pay Constellation Energy a premium as part of a long-term power purchase agreement (PPA) related to the Three Mile Island nuclear plant in Pennsylvania,

A newly inked 20-year power purchase agreement (PPA) between Constellation Energy Corp. and Microsoft is set to pave the way for the launch of a new clean energy center in Pennsylvania and the restart of

Constellation Energy ( NASDAQ:CEG) announced that it will restart TMI Unit 1 to provide 835 MW of carbon emission free nuclear power. Under an agreement with Microsoft, the computer system giant will purchase power from the restarted plant over a 20 year period in a deal worth an estimated at $16 billion over the life of the agreement.