This report covers financial, operational and socio-environmental results for the operations performed by CTEEP and its subsidiaries during the period from January 1 to December 31, 2012. For the fifth year running, the Company has prepared its Annual Sustainability Report in accordance with the guidelines of the Global Reporting Initiative (GRI) reporting framework. Moreover, for the first time, we have compiled the report so as to meet the criteria set out in the GRI Application Level Check methodology, which certifies whether the application of the GRI guidelines have been complied with, in addition to assuring coverage of the set of disclosure items required for the application level adopted and self-declared by the report preparer (Level B). The application of GRI guidelines aims at enhancing the quality and transparency of the Company`s reporting practices as regards its performance and management approach, in its quest for a positive and comprehensive impact on its operations, in addition to reinforcing the consistent approach to transparency most valued by the Company. (GRI 3.1, 3.2, 3.3)

Performance indicators presented in this report concern data for CTEEP and its regional offices, and do not include those of subsidiaries and joint ventures, except where indicated otherwise. There are no specific limitations on the scope or boundary applied to this report. Throughout the course of this document, wherever appropriate, there shall be information concerning changes as to the scope, boundary or the measurement methodology applied to any performance indicators, as well as on the effect of any re-statement of data provided in the 2011 Report. (GRI 3.5, 3.6, 3.7, 3.8, 3.9, 3.10, 3.11)

For the preparation of this report, Management has also taken into account the applicable GRI Sector Supplement indicators for the electric power sector, coupled with the recommendations laid down by ANEEL (the Brazilian Electric Power Agency) to assist the report preparers operating in the electric power industry to compile an annual sustainability report. The definition of the set of topics covered herein was based on the survey conducted in 2011 that compiled the input from a wide range of stakeholders. Moreover, the preparation of this report also considered the criteria laid down by ABRASCA (the Brazilian Publicly-Held Companies` Association), the Communication Policy established by the United Nations Global Compact – of which CTEEP has been a signatory since 2011, as well as the Social Balance Statement of IBASE (the Brazilian Social and Economic Analyses Institute). (GRI 4.12)

The data presented herein have been recorded and monitored by means of integrated software platform that provides support to the planning of corporate and human resources, in addition to other tools, analyses of internal documents, as well as the conduction of interviews with the Organization`s executive officers. (GRI 3.9)

The consolidated financial statements are presented in local currency (R$) and have been audited by the external company Ernst & Young Auditores Independentes S.S., in accordance with both the accounting practices adopted in Brazil and those laid down by the IFRS (International Financial Accounting Standards). (GRI 3.13)

The process of development and content definition of this report have been supervised by the areas of Communication and Strategic Management, as well as by the Financial and Investor Relations Division. The final version is subject to validation by the CEO, as well as by other officers, directors and managers. The compilation of information also relies on the participation of employees from different areas and positions.