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27. REVENUE (Details 1) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 BRL (R$) GW | Dec. 31, 2019 BRL (R$) GW | Dec. 31, 2018 BRL (R$) GW
Disclosure of revenue [line items] |  |  |  |  |  |  |
Supply of electricity in GWh | GW | [1] | 39,368 |  | 42,176 |  | 43,522 |
Own consumption | GW | [1] | 34 |  | 38 |  | 41 |
Unbilled revenue | GW | [1] |  |  |  |  |  |
Supply of electricity including own consumption and not invoiced | GW | [1] | 39,402 |  | 42,214 |  | 43,563 |
Wholesale supply to other concession holders | GW | [1] | 13,907 | [2] | 11,920 | [2] | 11,992 |
Wholesale supply unbilled, net | GW | [1] |  |  |  |  | 0 |
Total | GW | [1] | 53,309 |  | 54,134 |  | 55,555 |
Revenue from sale of electricity | R$ |  | R$ 23,009 |  | R$ 23,918 |  | R$ 21,834 |
Own consumption | R$ |  |  |  | 0 |  | 0 |
Unbilled revenue | R$ |  | 9 |  | 134 |  | 48 |
Supply of electricity including own consumption and not invoiced | R$ |  | 23,018 |  | 24,052 |  | 21,882 |
Wholesale supply to other concession holders | R$ | [2] | 3,363 |  | 2,943 |  | 3,002 |
Wholesale supply unbilled, net | R$ |  | 51 |  | (67) |  | (12) |
Revenue from sale of electricity | R$ |  | R$ 26,432 |  | R$ 26,927 |  | R$ 24,872 |
Residential [member] | Electricity distribution [member] |  |  |  |  |  |  |
Disclosure of revenue [line items] |  |  |  |  |  |  |
Supply of electricity in GWh | GW |  | 10,981 | [1] | 10,538 | [1] | 10,267 | [3]
Revenue from sale of electricity | R$ |  | R$ 9,875 |  | R$ 9,668 |  | R$ 8,658 |
Industrial [member] | Electricity distribution [member] |  |  |  |  |  |  |
Disclosure of revenue [line items] |  |  |  |  |  |  |
Supply of electricity in GWh | GW |  | 12,731 | [1] | 14,873 | [1] | 17,689 | [3]
Revenue from sale of electricity | R$ |  | R$ 4,171 |  | R$ 4,760 |  | R$ 4,892 |
Commercial, services and others [member] | Electricity distribution [member] |  |  |  |  |  |  |
Disclosure of revenue [line items] |  |  |  |  |  |  |
Supply of electricity in GWh | GW |  | 8,571 | [1] | 9,335 | [1] | 8,380 | [3]
Revenue from sale of electricity | R$ |  | R$ 4,979 |  | R$ 5,439 |  | R$ 4,683 |
Rural [member] | Electricity distribution [member] |  |  |  |  |  |  |
Disclosure of revenue [line items] |  |  |  |  |  |  |
Supply of electricity in GWh | GW |  | 3,766 | [1] | 3,795 | [1] | 3,615 | [3]
Revenue from sale of electricity | R$ |  | R$ 2,190 |  | R$ 2,058 |  | R$ 1,794 |
Public authorities [member] | Electricity distribution [member] |  |  |  |  |  |  |
Disclosure of revenue [line items] |  |  |  |  |  |  |
Supply of electricity in GWh | GW |  | 714 | [1] | 905 | [1] | 871 | [3]
Revenue from sale of electricity | R$ |  | R$ 522 |  | R$ 654 |  | R$ 575 |
Public lighting [member] | Electricity distribution [member] |  |  |  |  |  |  |
Disclosure of revenue [line items] |  |  |  |  |  |  |
Supply of electricity in GWh | GW |  | 1,243 | [1] | 1,357 | [1] | 1,384 | [3]
Revenue from sale of electricity | R$ |  | R$ 550 |  | R$ 614 |  | R$ 585 |
Public services [member] | Electricity distribution [member] |  |  |  |  |  |  |
Disclosure of revenue [line items] |  |  |  |  |  |  |
Supply of electricity in GWh | GW |  | 1,362 | [1] | 1,373 | [1] | 1,316 | [3]
Revenue from sale of electricity | R$ |  | R$ 722 |  | R$ 725 |  | R$ 646 |
[1] | Data not reviewed by external auditors
[2] | Includes a CCEAR (Regulated Market Sales Contract), bilateral contracts with other agents, and the revenues from management of generation assets (GAG) for the 18 hydroelectric plants of Lot D of Auction no 12/2015.
[3] | Data not audited by external auditors.

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