Dec. 10 (Bloomberg) -- Brazil plans to sell the right to build a 12 billion real ($6.8 billion) hydroelectric project today, reviving plans for large-scale dams in the Amazon to meet the energy needs of Latin America's biggest economy.

Paris-based Suez SA, Endesa SA of Spain and units of Centrais Eletricas Brasileiras SA, Brazil's state-controlled utility holding company, are among the qualified bidders. The winner of a 30-year concession to build and operate the 3,140- megawatt Santo Antonio plant on the Madeira River must offer the lowest price for electricity.

Santo Antonio is Brazil's first major hydroelectric project in 13 years, the first of three Amazon river dams that the government hopes will ease the need for fossil fuels. Brazil stopped building large dams in the 1990s as concern rose about their impact on the environment and public finance. The 14,000 megawatt Itaipu dam alone saddled Eletrobras, as the company is known, and the government with $20 billion in debt.

``Brazil is about to embark on a major increase in hydroelectric power,'' said Mano Lopes, investor relations officer for Brazil's Inepar Group, a maker of hydroelectric turbines in partnership with General Electric Co. ``Without it, the economy will have trouble growing.''

Brazil's economy grew 5.4 percent in the second quarter, the last period for which there is complete data, the fastest rate in three years and the second-fastest growth in more than a decade.

10 Million Homes

The country gets three-quarters of its electricity from hydropower. The three Amazon projects would increase the country's generation capacity by 12 percent, or 12,150 megawatts.

The Santo Antonio dam is scheduled to start operating at the end of 2012 and to be fully operational by 2016, when its 45 turbines are expected to generate energy for 10 million Brazilian homes.

Energy companies and consultants estimate the project will cost as much as 12 billion reais. The government said it will cost 9.5 billion reais, based on 2006 prices.

Activists stormed the building of Brazil's energy regulator in Brasilia around 6 a.m. local time to protest the planned construction. Police removed them at almost 10 a.m., when the auction was slated to start, and arrested seven people for damage to public property. The auction is now expected to start around 12:30 p.m., according Sergio Rosa, an Aneel official responsible for the auction.

The maximum auction price for electricity is 122 reais per megawatt-hour. The successful bidder will be the one that offers to charge the lowest price for the electricity from the dam, the regulator said in an e-mailed statement.

To contact the reporter on this story: Jeb Blount in Rio de Janeiro at jblount@bloomberg.net; Carlos Caminada in Sao Paulo at at ccaminada1@bloomberg.net

Last Updated: December 10, 2007 08:51 EST