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Operating Costs, Expenses and Other Revenue - Schedule of Operating Costs and Expenses (Details) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Disclosure of disaggregation of revenue from contracts with customers [line items] |  |  |  |
Energy purchased for resale | R$ 16,695 |  | R$ 14,648 | R$ 14,614
Basic network usage charges | 3,156 |  | 2,937 | 2,671
Gas purchased for resale | 2,127 | [1] | 2,237 | 2,735
Total costs of energy and gas | 21,978 |  | 19,822 | 20,020
Supply from itaipu binacional [member] |  |  |  |
Disclosure of disaggregation of revenue from contracts with customers [line items] |  |  |  |
Energy purchased for resale | 1,204 |  | 1,207 | 1,644
Physical guarantee quota contracts [member] |  |  |  |
Disclosure of disaggregation of revenue from contracts with customers [line items] |  |  |  |
Energy purchased for resale | 864 |  | 918 | 925
Quotas for Angra I and II nuclear plants [member] |  |  |  |
Disclosure of disaggregation of revenue from contracts with customers [line items] |  |  |  |
Energy purchased for resale | 374 |  | 364 | 357
Spot market [member] |  |  |  |
Disclosure of disaggregation of revenue from contracts with customers [line items] |  |  |  |
Energy purchased for resale | 1,154 |  | 478 | 530
Proinfa program [member] |  |  |  |
Disclosure of disaggregation of revenue from contracts with customers [line items] |  |  |  |
Energy purchased for resale | 468 |  | 511 | 598
Bilateral contracts [member] |  |  |  |
Disclosure of disaggregation of revenue from contracts with customers [line items] |  |  |  |
Energy purchased for resale | 499 |  | 510 | 493
Energy acquired in regulated market auctions [member] |  |  |  |
Disclosure of disaggregation of revenue from contracts with customers [line items] |  |  |  |
Energy purchased for resale | 4,564 |  | 3,940 | 3,334
Energy acquired in the free market [member] |  |  |  |
Disclosure of disaggregation of revenue from contracts with customers [line items] |  |  |  |
Energy purchased for resale | 5,655 |  | 5,612 | 6,003
Distributed generation ('geracao distribuida') [member] |  |  |  |
Disclosure of disaggregation of revenue from contracts with customers [line items] |  |  |  |
Energy purchased for resale | 3,239 |  | 2,331 | 1,977
PIS/pasep and cofins credits [member] |  |  |  |
Disclosure of disaggregation of revenue from contracts with customers [line items] |  |  |  |
Energy purchased for resale | 1,326 |  | 1,223 | 1,247
Basic network usage charges | (369) |  | (337) | (304)
Transmission Charges Basic Grid [Member] |  |  |  |
Disclosure of disaggregation of revenue from contracts with customers [line items] |  |  |  |
Basic network usage charges | 3,466 |  | 54 | 2,925
Distribution Charges [Member] |  |  |  |
Disclosure of disaggregation of revenue from contracts with customers [line items] |  |  |  |
Basic network usage charges | R$ 59 |  | R$ 3,220 | R$ 50
[1] | The price of the gas molecule acquired by Gasmig is corrected for the variation in Brent-type oil and the variation in the exchange rate.

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