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Revenue - Schedule of Revenue from Energy Supply (Details) R$ in Millions, MW in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 BRL (R$) MW | Dec. 31, 2023 BRL (R$) MW | Dec. 31, 2022 BRL (R$) MW
IfrsStatementLineItems [Line Items] |  |  |  |
Supply of electricity in MWh | MW | 50,554 |  | 49,688 | 47,518
Revenue from sale of electricity | R$ 29,699 |  | R$ 27,277 | R$ 26,365
Own consumption | MW | 30 |  | 30 | 31
Unbilled revenue | R$ 92 |  | R$ 166 | R$ 189
Supply of electricity including own consumption and not invoiced | MW | 50,584 |  | 49,718 | 47,549
Supply of electricity including own consumption and not invoiced | R$ 29,791 |  | R$ 27,443 | R$ 26,176
Wholesale supply to other concession holders | MW | 17,192 | [1] | 17,328 | 16,777
Wholesale supply to other concession holders | R$ 4,500 |  | R$ 4,183 | R$ 3,894
Wholesale supply unbilled, net | R$ 50 |  | R$ 45 | R$ 88
Total | MW | 67,776 |  | 67,046 | 64,326
Revenue from sale of electricity | R$ 34,341 |  | R$ 31,671 | R$ 30,158
Residential [member] | Electricity distribution [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Supply of electricity in MWh | MW | 14,430 | [2] | 13,311 | 11,956
Revenue from sale of electricity | R$ 12,970 |  | R$ 10,794 | R$ 10,133
Industrial [member] | Electricity distribution [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Supply of electricity in MWh | MW | 17,820 |  | 18,343 | 18,388
Revenue from sale of electricity | R$ 5,377 |  | R$ 5,903 | R$ 5,991
Commercial, services and others [member] | Electricity distribution [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Supply of electricity in MWh | MW | 11,802 |  | 11,443 | 10,410
Revenue from sale of electricity | R$ 6,613 |  | R$ 6,314 | R$ 6,155
Rural [member] | Electricity distribution [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Supply of electricity in MWh | MW | 3,578 |  | 3,507 | 3,359
Revenue from sale of electricity | R$ 2,528 |  | R$ 2,238 | R$ 2,050
Public authorities [member] | Electricity distribution [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Supply of electricity in MWh | MW | 1,031 |  | 973 | 863
Revenue from sale of electricity | R$ 937 |  | R$ 786 | R$ 660
Public lighting [member] | Electricity distribution [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Supply of electricity in MWh | MW | 973 |  | 1,056 | 1,138
Revenue from sale of electricity | R$ 546 |  | R$ 498 | R$ 535
Public services [member] | Electricity distribution [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Supply of electricity in MWh | MW | 920 |  | 1,055 | 1,404
Revenue from sale of electricity | R$ 728 |  | R$ 744 | R$ 841
[1] | Includes Sale Contracts in the Regulated Market (CCEARs – Contratos de Comercialização de Energia no Ambiente Regulado) through the Surplus and Deficits Offsetting Mechanism (MSCD: Mecanismo de Compensação de Sobras e Déficits), sales on the Free Market, and the revenues from management of generation assets (GAG – Gestão de Ativos da Geração) for the 18 hydroelectric plants of Lot D of Auction no 12/2015.
[2] | Data not audited by independent auditors.

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