He said Brazil's economic growth meant 4,500 megawatts (MW) of new electricity generation capacity was needed each year.

The deal to build, own, operate and market the 3,300 MW Jirau project, on the Madeira river, was awarded to a consortium led by Suez late on Monday.

Suez has a 50.1 percent stake in the project that will require a total investment of 3.3 billion euros ($5.14 billion) and will start production in 2012.

The group beat a consortium that included an investment fund set up by Spain's Santander and Portugal's Banif.

About 70 percent of the electricity to be produced by the Jirau plant was pre-sold to local electric power distributors at 71.4 Brazilian reals ($43.27) per MW, Beeuwsaert said, which represents guaranteed revenue of 9.6 billion euros for the consortium over 30 years from 2013.

The price will be significantly lower than the 130 reals per MW at which Suez and its consortium partners are set to sell the remaining 30 percent on the free market.

But Beeuwsaert insisted the project would remain profitable.

"As in all our other projects, we have very strict rules on profitability. I can tell you that other projects, and we are certain that this one will be as well, are largely above the criteria we set ourselves in terms of profitability," he said.

Apart from Suez, the winning consortium is made up of two subsidiaries of Brazil's federal power holding Eletrobras, Chesf and Eletrosul, as well as private construction conglomerate Camargo Correa.