The current document is the result of an entire internship project that presents an analysis of the technical electrical losses that occur in the electrical network of the Caldas, Quindío, and Risaralda (CQR) subarea. The project was based on the electrical model of the regional transmission system (STR), compared to the electrical model of the local distribution system (SDL), both of which were developed during the internship at the renowned company LICA RENEWABLE ENERGY. This company is mainly dedicated to the development of various types of electrical studies, primarily connection studies for the allocation of transport capacity in the National Interconnected System (SIN) of solar generation projects and the design of high and medium voltage lines. The development of the document first provides context for the technical terms that will be used throughout the document. Following this, the internship project is presented, which describes the justification, objectives, and methodology used during the internship. According to the methodology, the necessary information for the development of the electrical models is collected and synthesized, for which the Single Window of the Mining Energy Planning Unit (UPME), the SIN project report from the electrical system administrator XM, and the investment plans of the network operators (OR) in the study subarea, among others, were consulted. The obtained information allows for the elaboration of the electrical models together with the specialized power system simulation tool Power Factory DIgSILENT, in such a way that the technical requirements requested by the UPME for the allocation of transport capacity in the SIN are met. Once the electrical models have been developed, a calculation of technical electrical losses is carried out in both models for the years 2023, 2026, and 2029. These years are quite significant, as during this period, a large number of new generation projects with different types of generation technologies are integrated into the country's energy matrix. Similarly, a wide variety of network expansions, both in high and medium voltage, are undertaken during this period. Based on the above, critical elements present in each of the systems are identified. This allows contrasting the obtained results and determining the causes, effects, and possible solutions. Consequently, it is found that during the years of the analysis horizon, the regional transmission system is determined to have the highest amount of technical electrical losses overall. Additionally, the local distribution system shows lower efficiency, as it presents a greater amount of technical electrical losses in relation to the amount of power flowing through this system.