How adequate policies canpush renewables

After the Johannesburg World summit for Sustainable Development (WSSD), there has been growing interest in the establishment of a minimum share of renewable sources in the world energy matrix, which poses a question about how the new technologies can compete with the old ones. In Brazil , over the last 25 years, ethanol is used as a replacement of gasoline and the Brazilian electricity matrix reinforces the country's commitment, to utilize adequate policies for achieving sustainable development.