Houston power co. to raise more than $1 billion in debt

Houston-based Calpine Corp. is preparing for a private placement of notes to raise $1.25 billion in debt.

That figure increased by $500 million in less than a single day since Calpine first announced the offering on Dec. 10, according to press releases. The company intends to use the proceeds from the upsized offering first to buy back other debt notes, with anything left over going toward general corporate purposes.

Calpine plans to close its offering on Dec. 20.

Calpine already increased its…