From January 1 to October 28, 2026, operating restrictions ordered by ONS left 33.81 TWh of wind and solar generation unrealized in Brazil (22.50 TWh wind and 11.31 TWh solar), according to ONS open data, read by BrazilGrid; definition: per-cluster curtailment gated by restriction reason (curtailment ordered by ONS) plus the estimate for plants without data, the Curtômetro counter's yardstick (0.32 TWh estimated).
Over the same window of 2025 (January 1 to October 28, 2025) it was 32.73 TWh: 3.3% more in 2026.
Curtailment is not energy generated and thrown away: it is potential output that never happened. ONS estimates how much each plant could generate with the wind or sun of the moment (reference generation) and, for energy, reliability or grid reasons, orders it to generate less; the difference is the curtailment.
| Month | Wind | Solar | of which estimated | Total |
|---|---|---|---|---|
| January 2026 | 2,532.9 | 790.0 | 64.8 | 3,322.8 |
| February 2026 | 522.1 | 367.1 | 15.3 | 889.2 |
| March 2026 | 874.9 | 914.5 | 38.5 | 1,789.4 |
| April 2026 | 1,436.5 | 1,059.1 | 27.2 | 2,495.6 |
| May 2026 | 2,104.3 | 1,192.2 | 32.1 | 3,296.5 |
| June 2026 | 1,803.8 | 1,033.0 | 34.9 | 2,836.8 |
| July 2026 | 3,110.1 | 1,296.7 | 26.6 | 4,406.8 |
| August 2026 | 4,048.0 | 1,612.9 | 21.8 | 5,660.9 |
| September 2026 | 3,492.9 | 1,688.4 | 33.7 | 5,181.3 |
| October 2026 | 2,577.5 | 1,353.7 | 25.1 | 3,931.2 |
| Total 2026 (through 2026-10-28) | 22,503.0 | 11,307.5 | 319.9 | 33,810.5 |
| Same window of 2025 (through 2025-10-28) | 22,995.1 | 9,734.5 | 755.1 | 32,729.7 |
| Source | 2026 | 2025 | Change |
|---|---|---|---|
| Wind | 22,503.0 | 22,995.1 | -2.1% |
| Solar | 11,307.5 | 9,734.5 | +16.2% |
| Total | 33,810.5 | 32,729.7 | +3.3% |
| Month | Gated (ONS restriction) | Ungated | Ungated / gated |
|---|---|---|---|
| January 2026 | 3,351.6 | 4,286.0 | 1.28x |
| February 2026 | 919.0 | 2,024.4 | 2.20x |
| March 2026 | 1,831.3 | 2,829.5 | 1.55x |
| April 2026 | 2,555.0 | 3,463.1 | 1.36x |
| May 2026 | 3,365.0 | 4,430.2 | 1.32x |
| June 2026 | 2,873.6 | 4,001.9 | 1.39x |
| July 2026 | 4,478.8 | 5,459.5 | 1.22x |
| August 2026 | 5,739.8 | 6,677.0 | 1.16x |
| September 2026 | 5,240.8 | 6,164.4 | 1.18x |
| October 2026 | 4,001.6 | 4,984.9 | 1.25x |
| Total 2026 (through 2026-10-28) | 34,356.5 | 44,321.0 | 1.29x |
| Same window of 2025 (through 2025-10-28) | 32,901.4 | 41,160.7 | 1.25x |
Gated: only the half-hours in which ONS recorded a restriction (ENE, CNF or REL) — the yardstick of each plant's page. Ungated: every half-hour in which estimated generation exceeded measured generation, with or without an ONS order (includes estimation error and unavailability; not ordered curtailment). Both exclude only rows with invalid data and zero estimate. Neither is the total: summed per plant, the yardstick differs from the per-cluster one by a method difference that is never added to the counter.
From January 1 to October 28, 2026, operating restrictions ordered by ONS left 33.81 TWh of wind and solar generation unrealized in Brazil (22.50 TWh wind and 11.31 TWh solar), according to ONS open data, read by BrazilGrid; definition: per-cluster curtailment gated by restriction reason (curtailment ordered by ONS) plus the estimate for plants without data, the Curtômetro counter's yardstick (0.32 TWh estimated).
Not in the sense of energy generated and lost. It is potential output not realized: the plant could have generated (ONS estimate) and did not because the operator limited output. That is why BrazilGrid calls it curtailed generation.
Because there is more than one yardstick. Gated by reason (only where ONS recorded a restriction), the per-plant sum for 2026 through 2026-10-28 is 34.36 TWh; ungated (every estimate above measured output) it is 44.32 TWh. The counter yardstick, per cluster and including the estimate for plants without data, gives 33.81 TWh. Window, sources and definition change the number; every figure on this page states its own.
Over the same window of 2025 (January 1 to October 28, 2025) it was 32.73 TWh: 3.3% more in 2026.
On the Curtômetro (curtometro.brazilgrid.com), which counts curtailment since Oct 2021 on the same yardstick, and on each plant's page in gridAssets (usinas.brazilgrid.com), with the monthly series and the split by reason.
Updated 2026-10-29 15:29 (Brasília time, UTC-3) with data through 2026-10-28. Primary source: ONS open data (dados.ons.org.br); BrazilGrid reads and consolidates.