Duke Energy posted a solid first quarter, beating its financial performance for the same three-month period a year ago, as the company incrementally recovers from the recession.

But Duke CEO Jim Rogers said this morning on CNBC's "Squawk Box" program that it will take years for the electric utility to overcome the lingering aftereffects of the nation's most severe recession in eight decades.

Charlotte-based Duke, with utility operations in five states, reported an 8 percent increase in per share earnings to 39 cents, and a 15 percent boost in profit to $513 million, on operating revenue of $3.7 billion, a 2 percent increase.

At the same time, Rogers noted that residential sales were down over the past year while overall sales were flat. And he said the power company won't get back to its 2007 sales volume until the 2014-2015 time frame.