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May 9 (Reuters) - Duke Energy Corp, the biggest U.S. power company by generation capacity, reported a quarterly profit that edged past estimates, partly helped by its acquisition of Piedmont Natural Gas.
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.
Total operating expenses in the electric utilities and infrastructure segment fell 3.2 percent to $3.72 billion in the first quarter ended March 31, due to reduced storm restoration costs, the company said.
Net income attributable to Duke Energy was $716 million, or $1.02 per share, in the quarter, from $694 million, or $1.01 per share, a year earlier.
Excluding items, Duke Energy earned a profit of $1.04 per share, slightly beating analysts' average estimate of $1.03 per share, according to Thomson Reuters I/B/E/S.
Total operating revenue rose 6.5 percent to $5.73 billion.
The company also said it was on track to achieve its 2017 adjusted diluted earnings forecast of $4.50-$4.70 per share. (Reporting by John Benny in Bengaluru; Editing by Martina D'Couto)