U.S. nuclear power provider Constellation Energy on Friday agreed to buy privately-held natural gas and geothermal company Calpine Corp for $16.4 billion, marking one of the biggest acquisitions in the history of the U.

Constellation Energy struck a $26.6 billion deal to buy Calpine, uniting two of the U.S.'s largest power generators amid surging electricity demand from tech companies. Constellation shares rallied 3.

Constellation Energy Corp. shares surged to a record high after agreeing to acquire closely held Calpine Corp. for $16.4 billion in a deal that will create the largest fleet of US power stations.Most