This article seeks to evaluate some plants for electricity generation existing in Brazil, among which wind, thermal, hydroelectric and nuclear power, through the Full Cost Assessment tool. Two studies were prepared, the first deals with the analysis of these plants in view of the technical-economic, environmental and social factors. The second study is the analysis of these plants in view of the cost of energy and energy production in the five Brazilian regions - South, Southeast, Midwest, North and Northeast. The final results show that in the first study the wind farm had the highest valuation, so the best option among the others. However, the second study, wind power was the one that obtained the highest valuation for the Northeast Region, and the thermoelectric and hydroelectric plants had the highest valuation for the Southeast Region.