This publication presents a technical roadmap to transform Colombia’s electricity system toward a more reliable, clean, and lower-cost matrix. Using advanced modeling tools, the study analyzes scenarios for system expansion and operation with a high share of renewable energy, assessing costs, reliability, dynamic stability, fossil fuel consumption, emissions, and tariff impacts. The document concludes that Colombia can move toward an electricity system with more than 90% renewable generation, progressively reduce the use of coal and natural gas, maintain supply security, and generate economic benefits for users through regulatory, market, and infrastructure adjustments.