May 9 (Reuters) - Duke Energy Corp, the biggest U.S. power company by generation capacity, posted a 3.2 percent rise in quarterly profit on Tuesday, partly helped by its acquisition of Piedmont Natural Gas.
Net income attributable to Duke Energy was $716 million, or $1.02 per share, in the first quarter ended March 31, from $694 million, or $1.01 per share, a year earlier.
Total operating revenue rose 6.5 percent to $5.73 billion.
Duke Energy announced its $4.9 billion purchase of Piedmont Natural Gas in 2015. The acquisition has helped the company expand its natural gas distribution business. (Reporting by John Benny in Bengaluru; Editing by Martina D'Couto)