UPDATE 1-NRG Q3 earnings miss estimates

* Q3 EPS $1.02 vs est $1.14

* Weak commodity prices, higher costs weigh

* Rev up about 12 pct on recent acquisition

Oct 29 (Reuters) - Power producer NRG Energy Inc (NRG.N) reported lower quarterly earnings that missed estimates, hurt by weak commodity prices and higher operating costs. Net income for the third quarter was $278 million, or $1.02 a share, compared with $778 million, or $2.81 a share, last year.

Total operating revenue for the quarter rose about 12 percent to $2.92 billion, helped by NRG's acquisition of Reliant Energy Inc's (RRI.N) Texas retail business earlier this year.

Analysts on average were expecting earnings of $1.14 a share, before special items, on revenue of $1.93 billion, according to Thomson Reuters I/B/E/S.

Shares of the company closed at $24.81 Wednesday on the New York Stock Exchange. (Reporting by Hezron Selvi in Bangalore; Editing by Ratul Ray Chaudhuri)