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27. REVENUE (Details 2) - GW | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
RevenueLineItems [Line Items] |  |  |
Total amount of energy transported | [1] | 20,259 | 19,401
Industrial [member] |  |  |
RevenueLineItems [Line Items] |  |  |
Total amount of energy transported | [1] | 18,612 | 17,723
Commercial, services and others [member] |  |  |
RevenueLineItems [Line Items] |  |  |
Total amount of energy transported | [1] | 1,300 | 1,320
Rural [member] |  |  |
RevenueLineItems [Line Items] |  |  |
Total amount of energy transported | [1] | 32 | 17
Concessionaires [member] |  |  |
RevenueLineItems [Line Items] |  |  |
Total amount of energy transported | [1] | 315 | 341
[1] | Data not reviewed by external auditors

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