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17. PROPERTY, PLANT AND EQUIPMENT (Details 4) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Disclosure of detailed information about property, plant and equipment [line items] |  |
Total | R$ 101 | R$ 108
Usina de Queimado [meber] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Total | R$ 218 | 217
Usina de Queimado [meber] | Investment property completed [member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Stake in power output (%) | 82.50% |
Average annual depreciation rate (%) | 3.93% |
Usina de Queimado [meber] | Investment property completed [member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Stake in power output (%) | 82.50% |
Average annual depreciation rate (%) |  |
Accumulated depreciation [member] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Total | R$ (117) | (109)
Usina de Queimado [meber] |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Total | R$ 2 | R$ 1

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