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29. SEGMENT INFORMATION (Details Narrative) | 12 Months Ended
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Dec. 31, 2020
Energy [member] |
Disclosure of operating segments [line items] |
Description of assets | Itá Hydroelectric Plant, located in the State of Santa Catarina, with a capacity of 1,450 MW, in which CSN participates with 29.5%; Igarapava Hydroelectric Plant, located in Minas Gerais, with a capacity of 210 MW, in which CSN holds 17.9% of the capital; and 238 MW thermoelectric cogeneration plant, in operation at the Presidente Vargas Steelworks since 1999, which uses waste gas from the steel production itself as fuel.
Minerios Nacional [member] |
Disclosure of operating segments [line items] |
Percentage of ownership | 100.00%

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