Operador Nacional Do Sistema Elétrico - National Operator of the Electric System (ONS)

The National Electric System Operator (ONS) is the body responsible for coordinating and controlling the operation of electricity generation and transmission facilities in the National Interconnected System (SIN) and for planning the operation of isolated systems in the country, under the supervision and regulation of the National Electric Energy Agency (Aneel).

Established as a legal entity governed by private law, in the form of a non-profit civil association, the ONS was created on August 26, 1998, by Law No. 5,081/2004.

For the exercise of its legal attributions and the fulfillment of its institutional mission, the ONS develops a series of studies and actions carried out on the system and its proprietary agents to manage the different energy sources and the transmission network, in order to guarantee the security of continuous supply throughout the country, with the objectives of:
(a) promoting the optimization of the operation of the electro-energy system, aiming at the lowest cost for the system, observing the technical standards and reliability criteria established in the Grid Procedures approved by the Ring;
(b) ensure that all agents in the electricity sector have access to the transmission network on a non-discriminatory basis; and
(c) contribute, according to the nature of its activities, so that the expansion of the SIN is carried out at the lowest cost and aims at the best future operating conditions.

The ONS is composed of associate members and participating members, which are generation, transmission, distribution companies, free consumers, energy importers and exporters. The Ministry of Mines and Energy (MME) and representatives of Consumer Councils also participate.