Constellation Energy (NASDAQ:CEG) is close to a deal to purchase Calpine Corp. Constellation (NASDAQ:CEG) is in talks with Calpine's private equity owners over the terms of a deal that may value the power generation company at about $30 billion,

Constellation Energy Corp. is nearing an acquisition of Calpine Corp., people familiar with the matter said, in what would be one of the biggest ever deals in the power generation sector.Most Read from BloombergNYC’s Subway Violence Deters Drive to Bring Workers Back to OfficeDutch Central Bank Restores Amsterdam’s ‘Ugliest Building’NYC Condo Owners May Bear Costs of Landmark Green Building LawCan American Drivers Learn to Love Roundabouts?

Constellation Energy shares fell roughly 5% after reports it is in advanced talks to acquire closely held Calpine in a cash-and-stock deal. Shares in Constellation, the largest U.S. owner of nuclear-power plants,

S&P 500 nuclear stock Constellation Energy fell in afternoon trade on Wednesday after a report emerged that it's close to finalizing a deal for Calpine, a natural gas and geothermal power generator. Constellation Energy is in discussions with Calpine's private-equity owners about a deal that could value the company at about $30 billion including debt,