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FORM 6-K

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C.  20549

REPORT OF FOREIGN PRIVATE ISSUER
PURSUANT TO RULE 13a-16 OR 15d-16 OF
THE SECURITIES EXCHANGE ACT OF 1934

For the month of May 2011

Commission File Number 1-15224

Energy Company of Minas Gerais

(Translation of Registrant’s Name Into English)

Avenida Barbacena, 1200

30190-131 Belo Horizonte, Minas Gerais, Brazil

(Address of Principal Executive Offices)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F  x  Form 40-F  o

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):  o

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):  o

Indicate by check mark whether by furnishing the information contained in this Form, the registrant is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes  o No  x

If “Yes” is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b):  N/A

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Index

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Date: May 19, 2011

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1.               Presentation of the First Quarter 2011 Results

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2.               Earnings Release: First Quarter 2011 Results.

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IR Contacts

Chief Officer for Finance

and Investor Relations:

Luiz Fernando Rolla

General Manager,

Investor Relations:

Antônio Carlos Vélez Braga

Manager, Investor Markets:

Stefano Dutra Vivenza

Tel +55 (31) 3506-5024

Fax +55 (31) 3506-5026

ri@cemig.com.br

http://ri.cemig.com.br/

EARNINGS RELEASE

Cemig H

Comment by Cemig’s CEO, Mr. Djalma Bastos de Morais:

“The exceptional results that we present for the first quarter of 2011 reflect the success of our Long-term Strategic Plan, and of the strategy that is linked”

Mr. Luiz Fernando Rolla, CFO:

“new level of results, which reflects the correctness of our strategy of growing through acquisitions and new projects, within the process of consolidation of the Brazilian electricity sector.”

Headlines:

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Disclaimer

Certain statements in this material may represent expectations about future events or results that are subject to risks and uncertainties that may be known or unknown. There is no guarantee that the events or results referred to in these expectations will in fact take place.

These expectations are based on present assumptions and analyses from the point of view of our management, in accordance with their experience and other factors such as the macroeconomic environment, market conditions in the electricity sector, and expected future results, many of which are not under Cemig’s control.

Important factors that can lead to significant differences between actual results and the projections about future events or results include Cemig’s business strategy, Brazilian and international economic conditions, technology, Cemig’s financial strategy, changes in the electricity sector, hydrological conditions, conditions in the financial and electricity markets, uncertainty in relation to our results from future operations, plans, and objectives, and other factors.  Because of these and other factors the real results of Cemig may differ significantly from those indicated in or implied by such statements.

The information and opinions contained herein should not be understood as a recommendation to potential investors. No investment decision should be based on the veracity, currentness or completeness of this information or these opinions. None of Cemig’s professionals nor any of their related parties or representatives shall have any liability for any losses that may result from the use of the content of this presentation.

To evaluate the risks and uncertainties as they relate to Cemig, and to obtain additional information about factors that could originate different results from those estimated by Cemig, please consult the section on Risk Factors included in the Reference Form filed with the Brazilian Securities Commission — CVM — and on the 20-F form filed with the U.S. Securities and Exchange Commission — SEC.

(Figures in R$ ’000, except where otherwise indicated)

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Statements by the CEO and CFO

Cemig’s CEO, Mr. Djalma Bastos de Morais, makes the following comments:

“ The exceptional results that we present for the first quarter of 2011 reflect the success of our Long-term Strategic Plan, and of the strategy that is linked to it. By focusing on the long term, this Plan enables Cemig to present growing results, with a balanced portfolio of businesses, and with low risk.

After successfully making a number of acquisitions, Cemig is now very well positioned, in the context of an increasingly strong Brazilian economy, as indicated by the exceptional growth in the consumer market.

We do not cease to “do our homework”, growing in a balanced fashion across all our sectors, with our focus on operational excellence.

The results show that we are on the right path — and in particular that the decisions taken in the last few years are having the effect we intend: constantly adding value to our businesses, and making Cemig a company with continuously increasing strength and solidity, led by efficient corporate management”.

Cemig’s Chief Finance and Investor Relations Officer, Luiz Fernando Rolla, comments as follows:

“In this first quarter we have continued to generate consistent, robust cash flow as a result of our operations — and, as intended, add value to our businesses.

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Our Ebitda in 1Q11 is R$ 1.3 billion, 11% more than in the first quarter of 2010 — benefiting from our policy of maintaining high levels of operational efficiency.

This excellence is evidenced by our net income, of R$ 526 million in the first 3 months of this year, 1% more than in 1Q10.

We are now operating at a new level of results, which reflects the correctness of our strategy of growing through acquisitions and new projects, within the process of consolidation of the Brazilian electricity sector.

Even with its large universe of 58 companies and 10 consortia, the Cemig Group has operations that are synergetic, increasingly profitable, positioned with lower risk, and greater stability — and results that are always growing over the long term.

Our solid cash position of R$ 2.7 billion provides the basis for execution of our Strategic plan, dividend policy and debt management, and also the execution of planned investments, including those associated with acquisition opportunities.

The excellent results we present today show that we continue to add value, both continuously and sustainably, for all our shareholders — and all our other stakeholders.

In this release, we summarize the main points of our results for 1Q11. ”

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The economic context

The first quarter of 2011 continued to show signs of strengthening and recovery in the world’s leading economies.

Growth continued in the US, though at a modest seasonally adjusted rate of 1.8% p.a. in the first quarter, 1.9 percentage points lower than its year-on-year growth of 3.7% in first quarter 2010 (1Q10). Similarly, growth in the Eurozone to the end of March was 2.5%, which compares to 1Q10, led by Germany and the Netherlands. China, Brazil’s largest export destination, reported 12-month GDP growth of 9.7% to the end of 1Q11. Industrial production in Japan was down 4.5% year-on-year in the quarter, representing a reversal of 6.2 percentage points from the growth of 1.7% reported in 1Q10. Year-on-year growth in industrial production in Argentina, one of Brazil’s leading export customers, was 6.4% in the quarter, lower than the year-on-year growth of 14.25% reported in 1Q10.

In the Brazilian economy, strongly based on exports, aggregate demand was strong, reflecting growth in income, strong performance in the labor market, expansion of lending, and high levels of consumer and business confidence.

Brazil recorded its lowest-ever recorded average unemployment rate for a first quarter, of 6.3%, which compares to 7.4% in 1Q10. And real wages were up 4.0% in 1Q11 — the highest year-on-year comparison in many years. Lending was higher from the same period of the last year, with lending to individuals up 13.2%, and lending to

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companies up 9.9%. Confidence indices were optimistic. The consumer confidence indicator was up 1.4% from a year ago; and the National Industries Federation’s business confidence index, though down 9.7% from last year, was still high at 60.5.

Industrial production, by volume, was up 2.1% year-on-year in Brazil, and 3.8% in Minas Gerais — the state where the majority of Cemig’s revenue is concentrated:

Sources: Brazilian Geography and Statistics Institute (IBGE); Brazilian Finance Ministry.

Note that the rate of expansion of industrial production of the state of Minas Gerais overtook that of Brazil at the end of 2009, and has remained ahead of it during 2010 and 2011.

Industrial production indicators in two other important industries — mining and the automobile industry — have accommodated slightly in the first quarter, though at high levels:

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Sources: Brazilian Geography and Statistics Institute (IBGE); Brazilian Finance Ministry.

The auto industry and mining are leading elements of the economy of Minas Gerais, the state in which Cemig generates most of its revenue.

Early in the year, the imbalance between high domestic absorption and industrial production continued to pressure inflation, which reached the upper limit of the inflation target range (6.5%) — the center of the range is 4.5%. During the quarter the Central Bank’s Monetary Policy Committee (Copom) raised the basic (Selic) interest rate twice, by 0.25 percentage points in January and by 0.5 percentage points in March, bringing it to 11.75% at the end of the quarter. The Central Bank expects that its interest rate policy, together with macroprudential measures being taken since last year, will bring inflation within the target in 2012.

Electricity consumption in 1Q11 was higher than in 1Q10 in all the consumer categories: residential consumption was 3.5% higher, consumption by industrial consumers was 5.3% higher, consumption by the commercial user category was up 6.1%, and consumption by rural and other consumers was 3.1% higher.

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Sources: Eletrobras

In the whole of Brazil, these categories consumed the following average volumes of electricity per month in the first quarter of 2011:

·                  Industrial  14,817 GWh

·                  Residential  9,587 GWh

·                  Commercial  6,321 GWh

·                  Others  5,046 GWh

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Stock prices: performance

Economic summary

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Adoption of International Financial Standards

The results below are reported under the new Brazilian accounting practices, which arose from the process of harmonization of Brazilian accounting rules with International Financial Reporting Standards.  The results for the first quarter of 2010 have been restated to reflect these changes and to allow comparability with the first quarter of 2011.

Cemig’s consolidated energy market

Cemig’s market comprises the sale of electricity by Cemig D, Cemig GT consolidated (Cemig GT itself plus Cachoeirão, Pipoca and the proportionate holdings in the Parajuru, Morgado and Volta do Rio wind farms), the subsidiaries and affiliates (Horizontes, Ipatinga, Sá Carvalho, Barreiro, Cemig PCH, Rosal and Capim Branco) and Light (in proportion to Cemig’s holding).

These include sales both to captive consumers and free clients, in the concession area of Minas Gerais and outside the State, and also the sale of electricity to other agents of the electricity sector in the Free and Regulated Markets, and the sales under the Proinfa program to encourage alternative electricity sources, and on the CCEE (wholesale market) — eliminating transactions between companies of the Cemig group.

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In 1Quartely 2011, Cemig sold a total of 17,981 GWh, 16% more than in 2009 (15,518).

The figure includes a large volume of electricity sold to industrial consumers, totaling 6,257 GWh — the result of the strong economic growth and of Cemig’s position as leader in the free market in electricity in Brazil, another highlight is our sales under the residential, which grew by 21% — to 2,832 GWh — in 1Q11.

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This chart shows the breakdown of the Cemig Group’s sales to final consumers:

The electricity market of Cemig GT

Revenue from supply of electricity

This table shows supply of electricity by type of consumer:

In GWh

(*)   Includes Contracts for Sale of Electricity in the Regulated Market (CCEARs), and “bilateral contracts” with other agents.

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Revenue from use of the network

This refers to the tariff charged to agents in the electricity sector, including Free Consumers connected to the high voltage network, for use of that part of the National transmission Grid that is owned by the Company.

The electricity market of Cemig D

On April 8, 2011 Aneel published the result of the Tariff Adjustment of Cemig D. The Company’s tariffs were differentiated by voltage level, and the average impact was an increase of 6.04%, effective on that date.

Revenue from supply of electricity

Revenue from supply of electricity in 1Q11 was R$ 2,326,835, compared to R$ 2,303,663 in 1Q10.

The main impacts on revenue from sales to final consumers in 1Q11 arose from:

·      The quantity of electricity supplied to final consumers was 7.52% higher year-on-year.

·      Tariff increase with average impact on consumer tariffs of 1.67%, from April 8, 2010 (full effect in 1Q11).

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Electricity sold to final consumers (MWh)

(Figures not reviewed by external auditors)

In GWh

The categories with the largest year-on-year increases were the residential, industrial and commercial categories, respectively 7.27%, 10.33% and 7.10%.  The increases in these categories were mainly due to an increased number of consumers, expansion of industrial activity, and growth in private consumption, due to the favorable economic conditions in the state of Minas Gerais.

In spite of the quantity of electricity sold being 7.52% higher, revenue was only 1.01% higher. This result is substantially due to the effects arising from the regulatory assets and liabilities being transferred to tariffs in the periods concerned.

Revenue from use of the network

This is revenue from the TUSD — Tariff for Use of the Distribution System — charged to Free Consumers on electricity sold to them. In first quarter 2011 this revenue was R$ 447,341, 35.50% more than its total of R$ 330,147 in first quarter 2010. This variation arises principally from the

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increase in the volume transported, as a result of the migration of captive consumers to the status of free consumers, and also from the greater industrial activity in 2011.

The electricity market of Light

Total electricity consumption in 1Q11, at 6,291 GWh, was 3.4% more than in 1Q10. Consumption by the residential category of consumers was 3.0% higher than in 1Q10, even though average temperatures were nearly 1°C lower than in 1Q10.

For more details on Light’s sales in the second quarter of 1Q11, please see the report on this link:

http://www.mzweb.com.br/light/web/arquivos/Light_S.A._Release_1Q11.pdf

Operational revenue

Revenue from supply of electricity

Gross revenue from supply of electricity in 1Q11 was R$ 3,969,051, 14.53% more than in 1Q10 (R$ 3,465,493).

Final consumers

The revenue from electricity sold to final consumers in 1Q11, excluding the group’s own consumption, was R$ 3,498,847, compared to R$ 3,097,476 in the first quarter of 2010.

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The main factors in this result are:

·      The volume of energy invoiced to final consumers (excluding Cemig’s own consumption) was 15,60% higher.

·      Tariff increase for Cemig D with average effect on consumer tariffs of 1.67%, starting from April 8, 2010.

·      Price adjustment in contracts for sale of electricity, most of which are indexed to the IGP—M inflation index.

·      In spite of the effects reported above, revenue is 14.53% higher, mainly because of the effects arising from regulatory assets and liabilities that were transferred to tariffs in the periods concerned.

Electricity sold to final consumers

In GWh

Revenue from wholesale electricity sales

The volume of electricity sold to other concession holders in 1H11 was 5.35% higher than in 1H10, for average price 4.56% higher, at R$ 106.95/MWh in 1Q112011, vs. R$ 102.29/MWh in 1Q10. As a result, revenue from wholesale supply to other concession holders was 10.15% higher year-on-year, at R$ 364,724 in 1Q2011, than in 1Q2010

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(R$ 331,127). Revenues from energy sold to other concession holders totaled R$ 3,410,217 in 1Q11, compared to R$ 3,237,078 million in 1Q10.

Revenue from use of the electricity distribution systems (TUSD)

The revenue from the TUSD (Tariff for Use of the Distribution System), received by Cemig D and Light, was 56.51% higher in 1Q11, at R$ 524,375, compared to R$ 335,042 in 1Q10. This revenue comes from charges made to Free Consumers on energy sold by other agents of the electricity sector, and its increase arises from a higher volume of transport of energy for free consumers, a consequence of the recovery of industrial activity and of migration of captive clients to the free market.

Revenue from use of the transmission grid

Revenue for use of the network was 3.51%, or R$ 11,153, higher year-on-year in 1Q11, at R$ 329,028, compared to R$ 317,875 in 1Q10.

This revenue is from the transmission capacity of Cemig GT made available to the national grid, and also from the jointly-controlled transmission subsidiaries, among which we highlight the transmission groups known as TBE and Taesa.

The increase in this revenue in 2011 is mainly due to acquisition of an interest in Taesa, in May 2010, through a public offer to acquire shares, which increased these revenues in 1Q11.

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Deductions from operational revenues

Deductions from operational revenues in 1Q11 totaled R$ 1,647,650, which was 18.27% more than in 1Q10 (R$ 1,393,136). The main variations in these deductions from revenue between the two years are as follows:

The Fuel Consumption Account — CCC

The deduction for the CCC charge was R$ 157,302 in 1Q11, compared to R$ 98,942 in 1Q10, an increase of 58.98%. This charge is for the costs of operation of the thermal plants in the national grid and in the isolated systems. It is prorated between electricity concession holders, on a basis set by an Aneel Resolution.

This is a non-controllable cost: in the distribution activity, the difference between the amounts used as a reference for calculation of tariffs and the cost actually incurred is compensated for in the next tariff adjustment. For the portion relating to transmission services the Company charges the CCC amount to Free Consumers on their invoices and passes it on to Eletrobrás.

CDE — Energy Development Account

The deduction from revenue for the CDE charge was R$ 122,855 in 1Q11, compared to R$ 110,176 in 1Q10, an increase of 11.51%. These payments are specified by a Resolution issued by the regulator, Aneel. This is a non-controllable cost: in the distribution activity, the

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difference between the amounts used as a reference for calculation of tariffs and the cost actually incurred is compensated for in the next tariff adjustment. For the portion related to transmission services the Company merely acts as a channel for the CDE amount, charging it to Free Consumers on their invoices and paying it on to Eletrobrás.

The other deductions from revenue are taxes, calculated as a percentage of amounts invoiced. Hence their variations are substantially proportional to the changes in revenue.

Ebitda

Cemig’s Ebitda in 1Q11 was 11% higher than in 1Q10:

(Method of calculation not reviewed by external auditors)

The higher Ebitda in 1Q11 than in 1Q10 mainly reflects Revenue 17.69% higher, partially offset by Operational costs and expenses (excluding Depreciation and amortization) 22.23% higher. The higher

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Operational costs and expenses in 1H11 than in 1H10 are reflected in Ebitda margin, which was 40.46% in 1Q2010, and 38.16% in 1Q 2010.

Ebitda and Net income  by business area, and by principal companies

Net income for the period

Cemig’s consolidated net income in 1Q11 was R$ 526,151, which compares with R$ 520,066 in 1Q10, an increase of 1.17%. This mainly reflects higher revenue due to volume of electricity sold being 3.11% higher year-on-year, in turn mainly due to higher industrial activity; and also to revenue from use of the grid up 3.51% year-on-year, due to the addition of the transmission company Taesa to the network in May 2010.

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Deductions from operational revenues

Deductions from operational revenues in 1Q11 totaled R$ 1,647,650, 18.27% more than in 1Q10 (R$ 1,393,136). The main variations in these deductions between the two years are:

The Fuel Consumption Account — CCC

The deduction for the CCC charge was R$ 157,302 in 1Q11, compared to R$ 98,942 in 1Q10, an increase of 58.98%. This charge is for the costs of operation of the thermal plants in the national grid and in the isolated systems. It is prorated between electricity concession holders, on a basis set by an Aneel Resolution.

This is a non-controllable cost: in the distribution activity, the difference between the amounts used as a reference for calculation of tariffs and the cost actually incurred is compensated for in the next tariff adjustment. For the portion relating to transmission services the Company charges the CCC amount to Free Consumers on their invoices and passes it on to Eletrobrás.

CDE — Energy Development Account

The deduction from revenue for the CDE charge was R$ 122,855 in 1Q11, compared to R$ 110,176 in 1Q10, an increase of 11.51%. These payments are specified by a Resolution issued by the regulator, Aneel. This is a non-controllable cost: in the distribution activity, the difference between the amounts used as a reference for calculation of tariffs and the cost actually incurred is compensated for in the next tariff

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adjustment. For the portion related to transmission services the Company merely acts as a channel for the CDE amount, charging it to Free Consumers on their invoices and paying it on to Eletrobrás.

The other deductions from revenue are taxes, calculated as a percentage of amounts invoiced. Hence their variations are substantially proportional to the changes in revenue.

Operational costs and expenses (excluding Financial revenue/expenses)

Operational costs and expenses (excluding Net financial revenue (expenses)) totaled R$ 2,327,125 in 1Q11, 20.74% more than in 1Q10 (R$ 1,927,335). This is mainly due to increases in the costs of Electricity bought for resale, and Outsourced services. There is more information on this in Explanatory Note 23 to the Consolidated Quarterly Information.

The following paragraphs outline the main variations in expenses:

Electricity bought for resale

The expense on electricity bought for resale in 1Q11 was R$ 1,075,760, 49.84% more than in 1Q10 (R$ 717,941). The higher amount is basically due to a higher volume of selling activity by Cemig GT — reflected in higher revenues. This is a non-controllable cost: in the distribution activity, the difference between the amounts used as a reference for calculation of tariffs and the cost actually incurred is

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compensated for in the next tariff adjustment.  There is more information on this in Explanatory Note 22 to the Consolidated Quarterly Information.

Personnel

Personnel expenses totaled R$ 281,967 in 1Q11, 4.27% less than in 1Q10 (R$ 294,543). This result is largely due to the reduction of the number for employees from 2010 to 2011, as a result of the Company’s Voluntary Retirement Program, the effect being partly offset by the average salary increase of 7% agreed in November 2010, in the negotiations for the annual Collective Work Agreement for 2010—11.

Charges for use of the transmission grid

The expense on charges for use of the transmission network in 1Q11 was R$ 189,614, 1.44% more than in 1Q10 (R$ 186,921).

These charges, set by an Aneel Resolution, are payable by electricity distribution and generation agents for use of the facilities that are components of the national grid. This is a non-controllable cost: in the distribution activity, the difference between the amounts used as a reference for calculation of tariffs and the cost actually incurred is compensated for in the next tariff adjustment.

Depreciation and amortization

Depreciation and amortization was 8.83% higher year-on-year: R$ 232,797 in 1Q11, compared to R$ 213,904 in 1Q10.

The increase effectively reflects the Company’s increased investment program, mainly in the distribution business.

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Post-employment  liabilities

Expenses on post-employment obligations totaled R$ 30,888 in 1Q11, 10.69% more than in 1Q10 (R$ 27,905). This expense represents the updating of the obligation, calculated in accordance with an actuarial opinion prepared by external consultants.

Operational provisions

Operational provisions totaled R$ 41,068 in 1Q11, compared to R$ 23,148 in 1Q10, an increase of 77.42%. The higher figure is mainly due to a reversal, in 1Q10, of the provision for civil lawsuits on the subject of tariff increases, due to finalization of the cases. Further information is given in Explanatory Note 22 to the Consolidated Quarterly Information.

Financial revenues (expenses)

The company posted net financial expenses of R$ 282,819 for 1Q11, which compares with net financial expenses of R$ 129,446 in 1Q10. The main factors affecting net financial revenues (expenses) were:

·                  Higher expense on costs of loans and financings: R$ 302,699 in 1Q11, compared to R$ 231,034 in 1Q10. The higher figure reflects entry of new financings, one of the most important being the issue

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of R$ 600,000 by Cemig GT in May 2010; and also the higher aggregate CDI rate over 1Q11 than in 1Q10 — the result of the increase in the Selic Rate by the Central Bank.

·                  Increase in the expense of monetary variation on Loans and financings in Brazilian currency: R$ 50,964 in 1Q11, compared to R$ 31,975 in 1Q10. This increase is due, substantially, to the higher volume of funds indexed to the IPCA in first quarter 2011 than in 1Q10, arising from financings obtained at the end of 1Q 2010.

For a breakdown of financial revenues and expenses, please see Explanatory Note 24 to the Consolidated Quarterly Information.

Income tax and Social Contribution tax

In 1Q11, Cemig posted expenses on income tax and Social Contribution tax of R$ 250,492, which was 32.25% of the pre-tax profit of R$ 776,643.

In 1Q10, Cemig posted expenses on income tax and Social Contribution tax of R$ 300,806, representing 36.65% of the pre-tax profit of R$ 820,872. These effective rates are reconciled with the nominal rates in Note 9 to the Consolidated Quarterly Information.

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Appendices

Cemig consolidated: Figures I to X (in R$ mn)

TABLE I

TABLE II

TABLE III

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TABLE IV

Sales per Company

Cemig Distribution

Independent Generation

Cemig GT

RME (25%)

Cemig Consolidated by Company

TABLE V

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TABLE VI

TABLE VII

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TABLE VIII

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TABLE IX