This study compares the economic viability of renewable energy technologies – wind, solar photovoltaic, concentrated solar thermal, biomass and wave power – to traditional generation technologies including hydroelectricity, nuclear power, coal power and gas power sources. The Levelised cost of Electricity (LCOE) for different generation technologies in Brazil are calculated by reviewing existing published literature and examining 13 case study projects. Initial results found that using a low (5%) discount rate, the hydroelectric plants had the lowest LCOE, but were only slightly cheaper than the wind power case studies. However, using a high (10%) discount rate, one of the wind power case studies actually had the lowest LCOE. Solar photovoltaic (PV) was found to be the most expensive technology followed by wave power and concentrated solar thermal power (CSP). It will be shown that grid connected distributed PV and concentrated solar thermal technology are largely undeveloped in Brazil due to the high price associated with importing solar power equipment into Brazil and also due to ineffective federal government policy. The environmental and social externality costs of fossil fuel plants and large scale hydroelectric dams (in the Amazon region) are also discussed. It will be demonstrated that wind power becomes the cheapest generation technology in Brazil, once all externality and transmission line costs are taken into consideration.