This great graphic was produced by ONS (Operador Nacional do Sistema Elétrico), the manager of the 78 gigawatt Brazilian power generation system. It shows all the hydro power plants in operation, their capacity in megawatts, in what watershed (bacia) they are located and their proximity to the coast (note that the ocean is in the bottom of the picture). In the center of the map you will see a list of companies (Agentes) that operate these plants (each power plant has a number that indicate its operator). Released early last year, this document has projections till 2014.

Click on the image and you will have the full picture. Or enter ONS website to download the image.