SAO PAULO, Jan 17 (Reuters) - The auction that will privatize Brazilian power generator Emae should take place in May, Sao Paulo state governor Tarcisio de Freitas said on Wednesday.

The new forecast represents a delay compared to a previous timeframe by the Sao Paulo government, which had intended to sell its entire stake in Emae in the first quarter of this year.

"The process has already been defined, the study is well advanced, and we should bring it to the market in May," Freitas said at a press conference.

An analysis that will set the base price of the auction is still being finalized, according to information previously released by the government.

Emae owns and operates a hydraulic and energy generating system that stretches across the Sao Paulo state. Its main asset is the Henry Borden hydroelectric plant, with 889 megawatts (MW) of power.

The company's portfolio also includes three smaller hydroelectric plants and a gas-fired plant with 472 MW of capacity leased to a subsidiary of state-run oil firm Petrobras .

The Sao Paulo state owns 97.6% of Emae's ordinary shares, or 39.0% of its total capital. Power giant Eletrobras is also a relevant shareholder with 64.8% of the company's preferred shares, or 39% of the total capital.

Eletrobras has no subscription rights to acquire shares in Emae. (Reporting by Leticia Fucuchima; Writing by Peter Frontini; Editing by Mark Porter)