Texas' surging growth in power demand was a big driver in the $26.6 billion deal to acquire Houston's largest private company.

Constellation is buying power natural gas and geothermal power provider Calpine in a cash-and-stock deal valued at approximately $16.4 billion, joining together two of the country’s biggest power companies.

Constellation Energy is nearing a roughly $30 billion deal to acquire power producer Calpine, people familiar with the matter said on Wednesday, a move that would significantly expand Constellation's generation assets at a time of rising U.

US energy giant Constellation Energy has agreed to acquire Calpine Corporation, an independent power producer, for $26.6 billion, including debt considerations. The transaction includes 50 million shares of Constellation stock, $4.5 billion in cash, and the assumption of about $12.7 billion in Calpine’s net debt.

Constellation Energy Corporation CEG and Calpine Corp. announced that they have entered into a definitive agreement under which CEG will acquire Calpine in a cash and stock transaction valued at an equity purchase price of nearly $16.