The GDF Suez chief executive said Tuesday his company's stake in the Estreito hydro-electric dam in northern Brazil reflected confidence in the future of the country's booming electricity market.

GDF Suez CEO Gerard Mestrallet will join President Dilma Rousseff Wednesday at the inauguration of the 1,087 megawatt (MW) dam on the Toncantins river on the border between Tocantins and Maranhao states.

"It s very important," the head of the French energy giant told AFP, noting that the dam's capacity, equivalent to that of one nuclear plant, will meet the energy needs of four million people.

"We continue to be very confident in the future of the Brazilian electricity market" which had installed capacity of 117 GW last year, Mestrallet also told a press conference.

Hydroelectricity represents 71 percent of Brazil's total capacity, compared with 15 percent for natural gas and six percent for oil.

GDF Suez, the largest private electricity producer in Brazil with a seven percent market share, has a 40 percent stake in the Estreito dam, along with Brazilian mining giant Vale with 30 percent, US aluminum giant Alcoa with 25.44 percent and Brazilian construction firm Camargo Correa Energia with 4.4 percent.

One of several hydroelectric projects designed to provide clean energy for a fast-growing economy, Estreito is dwarfed by the 14,000 MW Itaipu dam on the southern Parana river and the 11,000 MW Belo Monte dam currently under construction across the Xingu river, a tributary of the Amazon.

Mestrallet said Estreito represents a total investment of $2.5 billion, including $300 million for socio-economic programs in health, education and infrastructure.

In the Belo Monte area, Indigenous groups have been protesting over the harmful impact of the dam on their way of life while environmentalists have warned of deforestation, greenhouse gas emissions and irreparable damage to the ecosystem.

However, Mauricio Bahr, head of GDF Suez's Brazil operations, dismissed suggestions that Estreito would also harm the area's native population.

"The indigenous population is very far away. There is no direct impact whatsoever," he noted, adding that GDF Suez was also funding government assistance programs for the indigenous people.

He also insisted that the dam has no major environmental impact, notably on the river's water quality.

Environmental critics of Brazil's hydro-electric generation said the country should make greater use of its huge wind and solar power potential.

With revenues of 90.7 billion euros ($118 billion) last year, GDF Suez is a is a global energy player, employing more than 217,000 people in 70 countries, including many in Latin America.

Present in Brazil for more than 50 years in the electricity, water treatment and natural gas sectors, it has revenues of more than $2 billion and employs nearly 2,300 people.