CHARLOTTE, N.C. -- Power generator Duke Energy says its earnings rose 20 percent in the second quarter on strong results across all of its operations.

Charlotte-based Duke says it made $351 million, or 28 cents a share, for the quarter ended June 30 compared with $293 million, or 23 cents per share, in the second quarter of 2007. Revenue rose to $3.23 billion in the quarter from $2.97 billion a year ago.

Analysts surveyed by Thomson Financial expected profits of 25 cents a share on revenue of $3.1 billion. Those estimates typically exclude one-time events.

Duke delivers natural gas and electricity to about 4.4 million customers in the Carolinas, Indiana, Ohio and Kentucky. It also operates utility assets in Latin America.