This report is one of the GEI research series. Based on the requirements of sustainable development in Central and South America, it systematically studies the Central and South American Energy Interconnection. It is divided into 7 chapters. In Chapter 1, the development status of the economy, society, resources, environment, energy and power in Central and South America are introduced. In Chapter 2, the challenges for sustainable development and energy transition in Central and South America are analyzed and the development ideas for Central and South American Energy Interconnection are proposed. In Chapter 3, guided by achieving the 2°C global temperature control target, the development trend for energy and power transition in Central and South America is envisioned, with corresponding scenarios proposed. In Chapter 4, the distribution of clean energy resources and layout of large power generation bases are studied. In Chapter 5, based on the analysis of the power balance, the overall layout and interconnection schemes for Central and South American Energy Interconnection are proposed. In Chapter 6, the comprehensive benefits brought by building Central and South American Energy Interconnection are assessed. In Chapter 7, the clean energy and power development path with its scenario in Central and South America to achieve a targeted 1.5°C temperature control is envisioned.