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Schedule of electricity purchased for resale (Details) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | R$ 16,101 | R$ 12,111 | R$ 11,286
Supply From Itaipu Binacional [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 1,946 | 1,990 | 1,429
Physical Guarantee Quota Contracts [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 832 | 780 | 715
Quotas For Angra I And I I Nuclear Plants [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 244 | 303 | 269
Spot Market [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 1,224 | 1,497 | 1,886
Proinfa program [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 401 | 318 | 376
bilateral contracts [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 418 | 333 | 311
Energy Acquired In Regulated Market Auctions [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 6,242 | 3,334 | 3,021
Energy Acquired In The Free Market [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 4,976 | 3,977 | 4,098
Distributed Generation Geracao Distribuida [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 1,268 | 678 | 207
P I S Pasep And Cofins Credits [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | R$ (1,450) | R$ (1,099) | R$ (1,026)

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