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v3.22.1

Deductions on revenue (Details) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
IfrsStatementLineItems [Line Items] |  |  |
Taxes on revenues | R$ 10,464 | R$ 8,798 | R$ 9,297
Charges to the consumer | 3,215 | 2,924 | 3,054
Deductions from revenue | 13,679 | 11,722 | 12,351
I C M S Taxes [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Taxes on revenues | 6,993 | 6,098 | 6,358
Cofins Tax [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Taxes on revenues | 2,842 | 2,214 | 2,408
Pis And Pasep Tax [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Taxes on revenues | 618 | 481 | 524
Other Taxes [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Taxes on revenues | 11 | 5 | 7
Global reversion reserve [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Charges to the consumer | 15 | 16 | 16
Energy efficiency program [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Charges to the consumer | 74 | 73 | 69
Energy development account [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Charges to the consumer | 2,658 | 2,443 | 2,448
Research and development [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Charges to the consumer | 34 | 43 | 41
National scientific and technological development fund [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Charges to the consumer | 55 | 43 | 41
Energy system expansion research [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Charges to the consumer | 27 | 21 | 20
Proinfa alternative source [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Charges to the consumer | 66 | 39 | 52
Energy services inspection fee [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Charges to the consumer | 35 | 35 | 30
Royalty on water resource [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Charges to the consumer | 37 | 62 | 43
Customer charges - the 'Flag Tariff' system [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Charges to the consumer | 162 | R$ 149 | R$ 294
Cde On R And D [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Charges to the consumer | 21 |  |
Cde On Eep [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Charges to the consumer | R$ 31 |  |

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