The National Electric System Operator (ONS) in Brazil is a technically proficient private institution supported by electricity sector companies, tasked with balancing electricity supply and demand across the National Interconnected System (SIN). Institutions with similar roles exist in various countries, with some owning the high-voltage transmission lines and substations that form the grid, while others, like the ONS, coordinate the collective operations of these assets with electricity generation plants.

The analogy of the SIN as an orchestra illustrates the dynamic role played by ONS, with thousands of "musicians"—the generating and transmitting agents—working under the guidance of a "conductor"—the ONS. This comparison underscores the often-overlooked significance of the ONS's function, as many people unfamiliar with the intricacies of the electricity sector may underestimate the contribution of such institutions.

To shed light on this, various studies in other countries have attempted to quantify the conductor's real contribution to the overall efficiency and management of the electrical system. Recognizing the ONS's pivotal role is essential for understanding how energy management can affect broader economic performance and energy sustainability in Brazil.