The National Electrical System Operator (ONS) is responsible for executing coordination and operation control activities related to the generation and transmission in the National Interconnected Electrical System (SIN). To accomplish these duties, the ONS receives an extensive data volume from the Electrical Sector Agents through a complex communication system. Then ONS generates fundamental information for the SIN operation by information processing and storage. Currently, the ONS features a very sophisticated conception EMS, the REGER, and also relies on the PI System. Not just as a data storage system, but as an extremely versatile system that is being used widely inside the company. From the valuable app generation for the Real-Time and Post Operation to the performance monitoring of all utilized computer platform. Passing through the performance monitoring of the communication systems utilized by the agents and ONS. In this presentation, the objective is to detail some of the most important applications for ONS that were developed with the use of the PI System and also to give a vision of the data volume received e how this is transformed in valuable and helpful information for the company’s final use.