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4. CONCESSIONS AND AUTHORIZATIONS (Details Narrative) - BRL (R$) R$ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 19, 2020 | Dec. 31, 2020
Disclosure Of Electricity Concessions And Authorizations [line items] |  |
Discount of future payments | 12.50% |
Concession grant fee | R$ 852 |
Dividend and interest on equity |  | 25.00%
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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