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4. CONCESSIONS AND AUTHORIZATIONS (Details Narrative) - BRL (R$) R$ in Millions |  |  |  | 12 Months Ended
--- | --- | --- | --- | ---
Sep. 26, 2019 | Sep. 19, 2019 | Dec. 14, 2018 | Dec. 31, 2019
Disclosure Of Electricity Concessions And Authorizations [line items] |  |  |  |
Discount of future payments | 107.00% |  |  |
Concession grant fee | R$ 891 | R$ 852 | R$ 852 |
Small Hydro Plants Enterprise [Member] |  |  |  |
Disclosure Of Electricity Concessions And Authorizations [line items] |  |  |  |
Discount of future payments |  |  |  | 12.50%
Cemig Distribution [Member] |  |  |  |
Disclosure Of Electricity Concessions And Authorizations [line items] |  |  |  |
Concession expired |  |  |  | Dec. 31, 2045
Two Thousand and Nineteen [Member] |  |  |  |
Disclosure Of Electricity Concessions And Authorizations [line items] |  |  |  |
Percentage of Selic rate |  |  |  | 80.00%
Two Thousand Twenty [Member] |  |  |  |
Disclosure Of Electricity Concessions And Authorizations [line items] |  |  |  |
Percentage of Selic rate |  |  |  | 111.00%

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