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Setor Elétrico
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Entry · Operation

SIN: National Interconnected System

What is the name of the country's interconnected electricity system?

● checked against the primary source on Sep 28, 2026Source: CCEE

Acronyms: CCEE, Electric Energy Trading Chamber; ONS, National Electric System Operator; EAR, Stored Energy.

In one sentence

Name of the country's interconnected electricity system. The CCEE describes the four submarkets (North, Northeast, South and Southeast) as submarkets "operating in the SIN".

Real example

Number read from the published database

On Sep 28, 2026, the EAR of the SIN, calculated as the sum of the EAR of the four subsystems divided by the sum of the maximum EAR, was 61.6% of the maximum EARNature of the data: Calculated.

No Check this number record of its own in this example: the number comes from the panel's published database, which carries the source and the reference date.

See in the panel

Calculated: Deterministic transformation made by Scrutiniums, with a published formula.

Why it matters

In the ONS datasets used here, the values come by subsystem (N, NE, S and SE). When the platform shows a SIN value, such as the EAR or the load of the SIN, it calculates it from the four, with the rule declared in the indicator.

How it is measured

It is not a quantity: it is the scope. When the platform calculates a value for the SIN, the indicator rule says how (for example, the EAR of the SIN is the sum of the EAR of the subsystems divided by the sum of the maximum EAR).

Not to be confused with

  • Submarket

    The SIN is the entire interconnected system; a submarket is each of its four divisions with its own PLD. A SIN value is a sum or a ratio of sums of the subsystems, according to the rule of each indicator.

  • Isolated Systems

    According to the ONS, the SIN is the group of four subsystems: South, Southeast/Center-West, Northeast and most of the North region. Isolated Systems are distribution systems that, in their normal configuration, are not connected to the SIN. A SIN value does not describe the localities served by Isolated Systems.

What cannot be concluded

  • The physical scope of the SIN (which isolated systems are excluded) was not checked in an ONS document.

Related entries

See in the panel

Official source

Documents accessed and text checked on Sep 28, 2026.