Constellation is buying natural gas and geothermal power provider Calpine for $16.4 billion, joining together two of the country's biggest power companies. The acquisition would create the nation’s ...

Calpine, the largest private company in Houston, announced a deal to be acquired by Baltimore-based Constellation for approximately $16.4 billion Friday morning. Constellation would buy Calpine ...

Constellation Energy agreed to buy Calpine for $16.4 billion, combining two of the country’s largest electricity generators at a time when their product is in high demand from tech companies.