Green tariff flag in October after five months of yellow

ANEEL confirmed on 25 September 2026 that the October tariff flag will be green, ending five consecutive months of yellow flag. Captive consumers no longer pay the additional BRL 1.885 per 100 kWh in force since May, according to the values published by the agency itself, which has maintained the flag system since 2015.

The cause is hydrological and short-lived. The ONS Monthly Operation Programme for October projects natural inflow energy of 193% of the long-term average in the South and 105% in the Southeast/Centre-West, but 61% in the Northeast and 43% in the North, with SIN load forecast at 85,274 MWavg, up 3.6% on October 2025.

The flag covers variation in generation cost, linked to reservoirs and thermal dispatch. It does not reach charges, transmission and distribution, which remain in the annual tariff adjustment. That is why a green month eases the bill without indicating a structural change in price, all the more so with uneven inflow between subsystems and expanding load.

For those building an investment case in self-owned generation, the reading is one of methodology. Payback calculated on the bill of a yellow-flag month overstates the gain; on a green month, it understates it. The monthly series published by the agency, and not the current month, is the defensible basis before an investment committee.