SAO PAULO, March 7 (Reuters) - Brazilian power producer Omega Energia SA plans to become a major renewable energy player in the United States in the coming years, its chief executive said, as it "cautiously" enters the market through a Texas launch planned this year.

Chief Executive Antonio Bastos told Reuters in an interview on Tuesday that the firm aimed to become "one of the top renewable players" in the world's largest economy, looking to profit from U.S. plans to expand the sector by 300 gigawatts in the next seven to 10 years.

Bastos did not disclose a time-frame or specific plans.

Omega, backed by investors such as British private equity firm Actis LLP, is set to start selling power later this year in Texas, where it is working on a 265.5-megawatt wind farm. It hopes to trade power through an online platform similar to one already used in Brazil.

"We are currently in talks with a large midstream company" to supply them with power, Bastos said, adding that the firm would also look at supplying smaller customers.

In Brazil, Bastos said, Omega's focus was on developing smaller on-site projects, mainly solar farms.

U.S. growth plans did not signal a shift away from Brazil, whose new government has stressed the importance of climate policy, Bastos said, but large greenfield projects have become less attractive in the South American country due to rising costs and oversupply. ($1 = 5.1853 reais) (Reporting by Leticia Fucuchima; Writing by Gabriel Araujo; Editing by Sarah Morland and Leslie Adler)