Constellation Energy buys Calpine in $26.6 billion deal
            
        
            
        
        
        
            Constellation Energy said today it would buy privately held Calpine Corp, a geothermal and natgas energy company, in a cash-and-stock deal valued at $26.6 billion including debt, sending Constellation's shares up 8.8%.
        
        
        
        
            
                Business
                 • 10 Jan