Helped by favorable weather and slightly improved retail usage, Progress Energy (PGN) reported on Friday a stronger-than-expected fourth-quarter profit, though flat revenue pushed its results lower year-over-year.

Last month, the company inked a deal to be acquired by Duke Energy (DUK) for $13.7 billion in a move that will create the largest U.S. power company with 7.1 million electricity customers and 57,000 megawatts of generating capacity. The deal is targeted to close by the end of this year, pending regulatory approvals.

The Raleigh, NC-based company posted quarterly earnings of $125 million, or 42 cents a share, compared with $154 million, or 55 cents a share, in the same quarter last year. Excluding one-time items, the company earned 45 cents a share, narrowly beating the Street’s view of 44 cents.

“Our continued financial discipline, coupled with very favorable weather, allowed us to achieve our financial goals and meet our commitment to customers and shareholders in 2010,” said Progress CEO Bill Johnson. “We delivered strong financial results, while making the investments necessary to meet customer needs now and in the future.”

Revenue for the electricity generator was $2.3 billion, matching year ago results and falling short of average analyst estimates polled by Thomson Reuters of $2.44 billion.

The company announced its full-year earnings guidance in the range of $3 to $3.20 a share, in line with Wall Street estimates of $3.14 a share.

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