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27. REVENUE (Details 5) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure of revenue [line items] |  |  |
Taxes on revenues | R$ 8,798 |  |
Charges to the consumer | 2,924 |  |
Deductions from revenue | 11,722 |  |
Restated [member] |  |  |
Disclosure of revenue [line items] |  |  |
Taxes on revenues |  | R$ 9,297 | R$ 8,767
Charges to the consumer |  | 3,054 | 3,547
Deductions from revenue |  | 12,351 | 12,314
Research and Development (R&D) [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer | 43 |  |
Research and Development (R&D) [member] | Restated [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer |  | 41 | 38
National Scientific and Technological Development Fund (FNDCT) [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer | 43 |  |
National Scientific and Technological Development Fund (FNDCT) [member] | Restated [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer |  | 41 | 38
Customer charges - Proinfa alternative sources program [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer | 39 |  |
Customer charges - Proinfa alternative sources program [member] | Restated [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer |  | 52 | 40
Other Taxes [member] |  |  |
Disclosure of revenue [line items] |  |  |
Taxes on revenues | 5 |  |
Other Taxes [member] | Restated [member] |  |  |
Disclosure of revenue [line items] |  |  |
Taxes on revenues |  | 7 | 8
Pis and pasep tax [member] |  |  |
Disclosure of revenue [line items] |  |  |
Taxes on revenues | 481 |  |
Pis and pasep tax [member] | Restated [member] |  |  |
Disclosure of revenue [line items] |  |  |
Taxes on revenues |  | 524 | 553
ICMS [member] |  |  |
Disclosure of revenue [line items] |  |  |
Taxes on revenues | 6,098 |  |
ICMS [member] | Restated [member] |  |  |
Disclosure of revenue [line items] |  |  |
Taxes on revenues |  | 6,358 | 5,657
Cofins [member] |  |  |
Disclosure of revenue [line items] |  |  |
Taxes on revenues | 2,214 |  |
Cofins [member] | Restated [member] |  |  |
Disclosure of revenue [line items] |  |  |
Taxes on revenues |  | 2,408 | 2,549
Energy services inspection fee [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer | 35 |  |
Energy services inspection fee [member] | Restated [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer |  | 30 | 26
Customer charges - the 'Flag Tariff' system [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer | 149 |  |
Customer charges - the 'Flag Tariff' system [member] | Restated [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer |  | 294 | 655
Royalties for use of water resources [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer | 62 |  |
Royalties for use of water resources [member] | Restated [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer |  | 43 | 45
Energy System Expansion Research (EPE of MME) [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer | 21 |  |
Energy System Expansion Research (EPE of MME) [member] | Restated [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer |  | 20 | 19
Energy Development Account (CDE) [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer | 2,443 |  |
Energy Development Account (CDE) [member] | Restated [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer |  | 2,448 | 2,603
Energy Efficiency Program (PEE) [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer | 73 |  |
Energy Efficiency Program (PEE) [member] | Restated [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer |  | 69 | 64
Global Reversion Reserve (RGR) [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer | R$ 16 |  |
Global Reversion Reserve (RGR) [member] | Restated [member] |  |  |
Disclosure of revenue [line items] |  |  |
Charges to the consumer |  | R$ 16 | R$ 19

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