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Revenue - Schedule of Revenue from Energy Supply (Details) R$ in Millions, MW in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 BRL (R$) MW | Dec. 31, 2022 BRL (R$) MW | Dec. 31, 2021 BRL (R$) MW
IfrsStatementLineItems [Line Items] |  |  |  |
Supply of electricity in MWh | MW | [1] | 45,769 | 44,865 | 43,229
Revenue from sale of electricity |  | R$ 27,277 | R$ 26,365 | R$ 26,665
Own consumption | MW | [1] | 30 | 31 | 33
Unbilled revenue |  | R$ 166 | R$ (189) | R$ (14)
Supply of electricity including own consumption and not invoiced | MW | [1] | 45,799 | 44,896 | 43,262
Supply of electricity including own consumption and not invoiced |  | R$ 27,443 | R$ 26,176 | R$ 26,651
Wholesale supply to other concession holders | MW | [1] | 17,328 | 16,777 | 10,825
Wholesale supply to other concession holders | [1] | R$ 4,183 | R$ 3,894 | R$ 3,023
Wholesale supply unbilled, net |  | R$ 45 | R$ 88 | R$ (55)
Total | MW | [1] | 63,127 | 61,673 | 54,087
Revenue from sale of electricity |  | R$ 31,671 | R$ 30,158 | R$ 29,619
Residential [member] | Electricity distribution [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Supply of electricity in MWh | MW | [1] | 12,092 | 11,217 | 11,186
Revenue from sale of electricity |  | R$ 10,794 | R$ 10,133 | R$ 11,124
Industrial [member] | Electricity distribution [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Supply of electricity in MWh | MW | [1] | 18,088 | 18,204 | 16,361
Revenue from sale of electricity |  | R$ 5,903 | R$ 5,991 | R$ 5,275
Commercial, services and others [member] | Electricity distribution [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Supply of electricity in MWh | MW | [1] | 9,469 | 8,957 | 8,334
Revenue from sale of electricity |  | R$ 6,314 | R$ 6,155 | R$ 5,520
Rural [member] | Electricity distribution [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Supply of electricity in MWh | MW | [1] | 3,063 | 3,093 | 3,975
Revenue from sale of electricity |  | R$ 2,238 | R$ 2,050 | R$ 2,566
Public authorities [member] | Electricity distribution [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Supply of electricity in MWh | MW | [1] | 956 | 856 | 729
Revenue from sale of electricity |  | R$ 786 | R$ 660 | R$ 583
Public lighting [member] | Electricity distribution [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Supply of electricity in MWh | MW | [1] | 1,056 | 1,138 | 1,226
Revenue from sale of electricity |  | R$ 498 | R$ 535 | R$ 718
Public services [member] | Electricity distribution [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Supply of electricity in MWh | MW | [1] | 1,045 | 1,400 | 1,418
Revenue from sale of electricity |  | R$ 744 | R$ 841 | R$ 879
[1] | Data not audited by external auditors.

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