Entry · Operation
Verified generation
How much do the plants generate hour by hour?
Acronyms: ONS, National Electric System Operator; SIN, National Interconnected System.
In one sentence
Generation of hydro, thermal, wind and photovoltaic plants in the ONS energy balance, verified hour by hour by subsystem.
Real example
In the 7 days to Sep 28, 2026, the verified generation of the SIN was 83,757 MWavg on average: 54.7% hydro, 10.6% thermal, 16.8% wind and 17.9% solarNature 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.
Calculated: Deterministic transformation made by Scrutiniums, with a published formula.
Why it matters
How it is measured
In MWavg, by hour and by subsystem, in the ONS “Balanço de Energia nos Subsistemas”.
Unit: MWavg, by hour and subsystem
Not to be confused with
Load is the energy served; centralized generation is the energy produced by the plants in the ONS balance. In each subsystem, generation minus load should correspond to the interchange; the Grid balance shows the hours when it does not.
MMGD (Distributed micro and mini generation)
MMGD connects to the distribution grid through the facilities of consumer units and is published as installed capacity (ANEEL) and as an estimated portion of the load (ONS); centralized generation is verified hour by hour at the plants in the ONS balance. Installed capacity is not generated energy.
Physical guarantee is not generation: the plant might generate more or less than it each month.
Verified generation is what the plants delivered in the ONS balance; constrained-off is the energy the plant did not generate by order of the ONS, estimated against a reference generation, only in the half hours in which the plant was limited. It is energy that verified generation does not contain.
What cannot be concluded
- The balance does not separate thermal plants by fuel.
- On Apr 29, 2023, SIN solar in the balance more than doubles from one day to the next, on the same date on which the ONS starts to include the estimate of distributed micro and mini generation in the load. The reading that the jump is this estimate is Scrutiniums', based on the data, and was not checked in an ONS document. Comparisons that cross the date are not homogeneous.
Related entries
In the learning paths
Official source
ONSOpen data portal, dataset “Balanço de Energia nos Subsistemas” (description and data dictionary)
Literal excerpt from the document
Portuguese only“Informações da carga e oferta de energia verificados em periodicidade horária por subsistema. A oferta é representada pelos valores de geração das usinas hidráulicas, térmicas, eólicas e fotovoltaicas, em MWmed.”
Documents accessed and text checked on Sep 28, 2026.