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.Including the assumption of debt,

Constellation Energy Corp. agreed to acquire closely held Calpine Corp. for $16.4 billion to add scores of power generation assets across the US as the nation’s electricity demand is forecast to surge.

Constellation Energy’s deal to buy Calpine is being driven by fast-rising demand for electricity in part by the technology industry’s investments in artificial intelligence.