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Schedule of distribution and sale of energy and gas (Details) | 12 Months Ended
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Dec. 31, 2021
Madeira Energia S A [Member] |
IfrsStatementLineItems [Line Items] |
Classification | Affiliated company
Description | Corporation engaged in the construction and commercial operation of the Santo Antônio Hydroelectric Plant, through its subsidiary Santo Antônio Energia S.A., in the basin of the Madeira river, in the State of Rondônia
Name of affiliated | Madeira Energia S.A. (‘Madeira’
Ativas Datacenter S A [Member] |
IfrsStatementLineItems [Line Items] |
Classification | Affiliated entity
Description | Corporation engaged in the supply of IT and communication infrastructure services, including physical hosting and related services for medium-sized and large corporations
Name of affiliated | Ativas Datacenter S.A. (‘Ativas’
Fip melbourne [member] |
IfrsStatementLineItems [Line Items] |
Classification | Affiliated entity
Description | Investment fund managed by Banco Modal S.A., whose objective is to seek appreciation of capital invested through acquisition of shares, convertible debentures or warrants issued by listed or unlisted companies, and/or other assets. This fund held 83% of the share capital of SAAG Investimentos S.A. (‘SAAG’), the objects of which are to own equity in Madeira Energia S.A. (‘Mesa’)
Name of affiliated | FIP Melbourne (Usina de Santo Antônio)
Guanhaes Energia S A [Member] |
IfrsStatementLineItems [Line Items] |
Classification | Jointly controlled entity
Description | Corporation engaged in the production and sale of energy through building and commercial
Name of joint venture | Guanhães Energia S.A. (‘Guanhães Energia’) (1)
Light Ger S A [Member] |
IfrsStatementLineItems [Line Items] |
Classification | Jointly controlled entity
Description | Corporation classified as independent power producer, formed to build and operate
Name of joint venture | LightGer S.A. (‘LightGer’) (1)
Usina Hidreletrica Itaocara S A [Member] |
IfrsStatementLineItems [Line Items] |
Classification | Jointly controlled entity
Description | Corporation, comprising the partners of the UHE Itaocara Consortium, formed by Cemig GT and
Name of joint venture | Usina Hidrelétrica Itaocara S.A. (‘UHE Itaocara’)
Axxiom Solucoes Tecnologicas S A [Member] |
IfrsStatementLineItems [Line Items] |
Classification | Jointly controlled entity
Description | Unlisted corporation, providing technology and systems solutions for operational management of public service concession holders, including companies operating in energy, gas, water and sewerage, and other utilities. Jointly controlled by Light (51%) and Cemig (49%)
Name of joint venture | Axxiom Soluções Tecnológicas S.A. (‘Axxiom’)
Hidreletrica Cachoeirao S A [Member] |
IfrsStatementLineItems [Line Items] |
Classification | Jointly controlled entity
Description | Production and sale of energy as an independent power produce
Name of joint venture | Hidrelétrica Cachoeirão S.A. (‘Cachoeirão’)
Hidreletrica Pipoca S A [Member] |
IfrsStatementLineItems [Line Items] |
Classification | Jointly controlled entity
Description | Independent production of energy, through construction and commercial operation
Name of joint venture | Hidrelétrica Pipoca S.A. (‘Pipoca’)
Retiro Baixo Energetica S A [Member] |
IfrsStatementLineItems [Line Items] |
Classification | Jointly controlled entity
Description | Corporation that holds the concession to operate
Name of joint venture | Retiro Baixo Energética S.A. (‘RBE’)
Amazonia Energia Participacoes S A [Member] |
IfrsStatementLineItems [Line Items] |
Classification | Jointly controlled entity
Description | Special-purpose company created by Cemig GT (74.50% ownership) and Light (25.50%), for acquisition of an equity interest of 9.77% in Norte Energia S.A. (‘Nesa’
Name of joint venture | Amazônia Energia Participações S.A (‘Amazônia Energia’
Alianca Norte Energia Participacoes S A [Member] |
IfrsStatementLineItems [Line Items] |
Classification | Jointly controlled entity
Description | Special-purpose company created by Cemig GT (49% ownership) and Vale S.A. 51%, for acquisition of an equity interest of 9% in Norte Energia S.A. (‘Nesa’)
Name of joint venture | Aliança Norte Energia Participações S.A. (‘Aliança Norte’)
Baguari Energia S A [Member] |
IfrsStatementLineItems [Line Items] |
Classification | Jointly controlled entity
Description | Corporation engaged in the construction, operation, maintenance and commercial operation
Name of joint venture | Baguari Energia S.A. (‘Baguari Energia’
Alianca Geracaode Energia S A [Member] |
IfrsStatementLineItems [Line Items] |
Classification | Jointly controlled entity
Description | Unlisted company created by Cemig GT and Vale S.A. as a platform for consolidation of generation assets held by the two parties in generation consortia, and investments in future generation projects. For their shares, the two parties subscribed the following generation plant assets
Name of joint venture | Aliança Geração de Energia S.A. (‘Aliança’)
Transmissora Aliancade Energia Eletrica S A [Member] |
IfrsStatementLineItems [Line Items] |
Classification | Jointly controlled entity
Description | Corporation engaged in the construction, operation and maintenance of energy transmission facilities all states of Brazil through direct and indirect equity interests in investees
Name of joint venture | Transmissora Aliança de Energia Elétrica S.A. (‘TAESA’)
U F V 1 [Member] |
IfrsStatementLineItems [Line Items] |
Name of joint venture | UFV Janaúba Geração de Energia
U F V 2 [Member] |
IfrsStatementLineItems [Line Items] |
Name of joint venture | Elétrica Distribuída SA
U F V 3 [Member] |
IfrsStatementLineItems [Line Items] |
Name of joint venture | UFV Corinto Geração de Energia
U F V 4 [Member] |
IfrsStatementLineItems [Line Items] |
Name of joint venture | Elétrica Distribuída SA
U F V 5 [Member] |
IfrsStatementLineItems [Line Items] |
Name of joint venture | UFV Manga Geração de Energia Elétrica
U F V 6 [Member] |
IfrsStatementLineItems [Line Items] |
Name of joint venture | Distribuída SA
U F V 7 [Member] |
IfrsStatementLineItems [Line Items] |
Name of joint venture | UFV Bonfinópolis II Geração de Energia
U F V 8 [Member] |
IfrsStatementLineItems [Line Items] |
Name of joint venture | Elétrica Distribuída SA
U F V 9 [Member] |
IfrsStatementLineItems [Line Items] |
Name of joint venture | UFV Lagoa Grande Geração de Energia Elétrica Distribuída SA,
U F V 10 [Member] |
IfrsStatementLineItems [Line Items] |
Name of joint venture | UFV Lontra Geração de Energia Elétrica Distribuída SA,
U F V 11 [Member] |
IfrsStatementLineItems [Line Items] |
Name of joint venture | UFV Mato Verde Geração de Energia Elétrica Distribuída SA,
U F V 12 [Member] |
IfrsStatementLineItems [Line Items] |
Name of joint venture | UFV Mirabela Geração de Energia Elétrica Distribuída SA,
U F V 13 [Member] |
IfrsStatementLineItems [Line Items] |
Name of joint venture | UFV Porteirinha Geração de Energia Elétrica Distribuída SA and
U F V 14 [Member] |
IfrsStatementLineItems [Line Items] |
Name of joint venture | UFV Porteirinha II Geração de Energia Elétrica Distribuída S.A.
U F V 15 [Member] |
IfrsStatementLineItems [Line Items] |
Name of joint venture | UFV Brasilândia Geração de Energia Elétrica Distribuída S.A.
U F V [Member] |
IfrsStatementLineItems [Line Items] |
Classification | Jointly controlled entity
Description | Generation of electric power from photovoltaic solar sources to the Distributed Generation market (‘Geração Distribuída’), with total installed capacity of 53.61MWp. The wholly owned subsidiary Cemig Sim and Mori Energia holds 49% and 51% of the total equity, respectively.
Renova Energia S A [Member] |
IfrsStatementLineItems [Line Items] |
Classification | Jointly controlled entity
Description | Listed company engaged in the development, construction and operation of plants generating power from renewable sources — wind power, small hydro plants (SHPs), and solar energy; trading of energy; and related activities, In-Court Supervised Reorganization. Renova is the owner of three Small Hydroelectric Plants, representing 5.7 MW of the total installed generation capacity of Cemig GT. In 2021 Cemig GT classified its equity interest in Renova as a non-current asset held for sale.
Name of joint venture | Renova Energia S.A. (‘Renova Energia’) — In-Court Supervised Reorganization (2)
Cemig Geracaoe Transmissao S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Cemig Geração e Transmissão S.A. (‘Cemig GT’ or ‘Cemig Geração e Transmissão’)
Classification | Subsidiary
Description | Wholly-owned subsidiary engaged in the energy generation and transmission services. Its shares are listed in Brazil, but are not actively traded. Cemig GT has interests in 67 power plants (60 of which are hydroelectric, 6 are wind power and 1 is solar) and associated transmission lines, most of which are part of the Brazilian national generation and transmission grid system, with total installed generation capacity of 5,755 MW (5)
Cemig Baguari [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Cemig Baguari
Classification | Subsidiary
Description | Corporation engaged in the production and sale of energy as an independent power producer and in interests in investees or joint operations that are engaged in the production and sale of energy in future projects.
Cemig geracao tres marias sa [member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Cemig Geração Três Marias S.A.
Classification | Subsidiary
Description | Corporation engaged in the production and sale of energy as public service concession holder, by commercial operation of the Três Marias Hydroelectric Plant, and sale and trading of energy in the Free Market. This subsidiary has installed capacity of 396 MW (5), and guaranteed offtake level of 239 MW (5) average.
Cemig Geracao Salto Grandes S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Cemig Geração Salto Grande S.A.
Classification | Subsidiary
Description | Corporation engaged in the production and sale of energy as public service concession holder, by commercial operation of the Salto Grande Hydroelectric Plant, and sale and trading of energy in the Free Market. This subsidiary has installed capacity of 102 MW (5), and guaranteed offtake level of 75 MW (5) average.
Cemig Geracao Itutinga S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Cemig Geração Itutinga S.A.
Classification | Subsidiary
Description | Corporation engaged in the production and sale of energy as public service concession holder, by commercial operation of the Itutinga Hydroelectric Plant, and sale and trading of energy in the Free Market. This subsidiary has installed capacity of 52 MW (4), and guaranteed offtake level of 28 MW (5) average.
Cemig Geracao Camargos S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Cemig Geração Camargos S.A
Classification | Subsidiary
Description | Corporation engaged in the production and sale of energy as public service concession holder, by commercial operation of the Camargos Hydroelectric Plant, and sale and trading of energy in the Free Market. This subsidiary has installed capacity of 46 MW
Cemig Geracao Sul S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Cemig Geração Sul S.A
Classification | Subsidiary
Description | Corporation engaged in the production and sale of energy as public concession holder, by commercial operation of the Coronel Domiciano, Marmelos, Joasal, Paciência and Piau Small Hydroelectric Plants, and trading in energy in the Free Market. Aggregate installed generation capacity is 39.53 MW (5); guaranteed offtake level of 27.42 MW (5) average.
Cemig Geracao Leste S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Cemig Geração Leste S.A.
Classification | Subsidiary
Description | Corporation engaged in the production and sale of energy as public concession holder, by operation of the Dona Rita, Sinceridade, Neblina, Ervália, Tronqueiras and Peti Small Hydroelectric Plants, and trading in energy in the Free Market. Aggregate installed generation capacity of these plants is 35.16 MW (5); guaranteed offtake level of 18.64 MW (5) average.
Cemig Geracao Oeste S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Cemig Geração Oeste S.A.
Classification | Subsidiary
Description | Corporation engaged in the production and sale of energy as public service concession holder, by commercial operation of the Gafanhoto, Cajuru and Martins Small Hydroelectric Plants, and sale and trading of energy in the Free Market. It has aggregate installed capacity of 28.90 MW (5), and guaranteed offtake level of 11.21 MW (5) average.
Rosal Energia S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Rosal Energia S.A. (‘Rosal’)
Classification | Subsidiary
Description | Corporation that holds the concession
Sa Carvalho S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Sá Carvalho S.A. (‘Sá Carvalho’)
Classification | Subsidiary
Description | Corporation that holds the concession to generate and sell energy
Horizontes Energia S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Horizontes Energia S.A. (‘Horizontes’)
Classification | Subsidiary
Description | Corporation that is classified as an independent power producer
Cemig P C H S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Cemig PCH S.A. (‘PCH’)
Classification | Subsidiary
Description | Corporation that is classified as an independent power producer
Cemig Trading S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Cemig Trading S.A. (‘Cemig Trading’)
Classification | Subsidiary
Description | Corporation engaged in trading and intermediation of energy.
Empresade Servicose Comercializacaode Energia Eletrica S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Empresa de Serviços e Comercialização de Energia Elétrica S.A.
Classification | Subsidiary
Description | Corporation engaged in the production and sale of energy as an independent power producer, in future projects.
Cemig Geracao Poco Fundo [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Cemig Geração Poço Fundo
Classification | Subsidiary
Description | Corporation engaged in the production and sale of energy, as an independent producer
Central Eolica Praiasde Parajuru S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Central Eólica Praias de Parajuru S.A
Classification | Subsidiary
Description | Corporation engaged in the production and sale of energy at the wind power plant of the same name in the northeastern Brazilian state of Ceará
Central Eolica Voltado Rio S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Central Eólica Volta do Rio S.A. (‘Central Eólica Volta do Rio’)
Classification | Subsidiary
Description | Corporation engaged in the production and sale of energy at the wind power plant of the same name in Acaraú, northeastern Brazilian state of Ceará
Cemig Distribuicao S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Cemig Distribuição S.A. (‘Cemig D’ or ‘Cemig Distribuição’)
Classification | Subsidiary
Description | Wholly owned subsidiary, whose shares are listed in Brazil but are not actively traded; engaged in the distribution of energy through networks and distribution lines throughout almost the whole of Minas Gerais State.
Companhiade Gasde Minas Gerais [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Companhia de Gás de Minas Gerais (‘Gasmig’
Classification | Subsidiary
Description | Corporation engaged in the acquisition, transportation and distribution of combustible gas or sub-products and derivatives, through a concession for the distribution of gas in the State of Minas Gerais.
Efficientia S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Cemig Sim (‘Efficientia’)
Classification | Subsidiary
Description | Corporation that provides energy efficiency and optimization services and energy solutions through studies and execution of projects; and services of operation and maintenance of energy supply facilities.
Companhia De Transmissao Centroeste De Minas Centroeste [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Companhia de Transmissão Centroeste de Minas (‘Centroeste’) (3)
Classification | Subsidiary
Description | Corporation engaged in the construction, operation and maintenance of the
Sete Lagoas Transmissora De Energia S A [Member] |
IfrsStatementLineItems [Line Items] |
Name of subsidiary | Sete Lagoas Transmissora de Energia S.A. (“SLTE”) (4)
Classification | Subsidiary
Description | Energy transmission service concession, through construction, operation and maintenance of the energy transmission infrastructure of the Sete Lagoas 4 Substation in the city of Sete Lagoas, Minas Gerais.

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