With these studies, a database was consolidated with technical and environmental parameters of the plants, such as: fuel used, thermodynamic cycle, types of control systems adopted, potential atmospheric emissions and use of water for cooling. Therefore, a data consolidation methodology was improved, including criteria for cases of missing or inconsistent information. This publication systematizes these data into emission rankings of fossil thermal power plants that supplied energy to the National Interconnected System in 2021, as well as their respective owners.