Together, Central and South America and the Caribbean represent more than 450 million people and 12% of the Earth's total emerged land. The region stands out in the global energy landscape for the outstanding contribution of renewable sources to its energy production. Maintaining this level of renewable energy in the future might prove a challenging task, as 'historical' energy sources (hydropower, biomass) run into sustainability issues and 'new' options (wind, solar, geothermal energy) still depend on public support schemes. However, South America's small fossil resource endowment and excellent renewable potential make it the ideal candidate for pioneering a renewable energy transition. The energy sector's contribution in fueling economic growth in a socially and environmentally sustainable way is also an issue that is particularly significant in the developing context on the continent. Climate change is a region-scale concern. The continent's emissions per capita are above the global average, and the region is also likely to be one of the most impacted by climate change. South America's energy sector is vulnerable both on the supply side (hydropower and biomass resources) and the demand side (increased demand for e.g. agriculture and air conditioning). Despite shared regional strengths and concerns, however, South America appears as a highly heterogeneous and fragmented continent. The region's physical layout is a stumbling block for regional integration. Two centuries of regional wars complicate political cooperation at national level, and the historical evolution has created strong disparities between national energy sectors. Various attempts to cooperate on transnational infrastructure have ended up as costly failures in past years.The aim of this PhD work, half of which was conducted in France and half in Chile, was to develop a mathematical model adapted to the study of long-term energy issues, at a regional scale, for South America. This model, TIMES-América Latina y el Caribe, was applied to studying ...