Exhibit 13.1 CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ENACTED PURSUANT TO SECTION 906 OF THE U.S. SARBANES-OXLEY ACT OF 2002 Espirito Santo Centrais Eletricas S.A. (the "Company") is filing with the U.S. Securities and Exchange Commission, on the date hereof, its annual report on Form 20-F for the fiscal year ended 2003 (the "Report"). I, Antonio Eduardo da Silva Oliva, Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. section 1350, as enacted pursuant to section 906 of the U.S. Sarbanes-Oxley Act of 2002, that, to the best of my knowledge: 1. the Report fully complies with the requirements of section 13(a) or 15(d) of the U.S. Securities Exchange Act of 1934; and 2. the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company. /s/ Antonio Eduardo da Silva Oliva - ---------------------------------- Antonio Eduardo da Silva Oliva Chief Executive Officer June 30, 2004 A signed original of this written statement required by Section 906 has been provided to the Company and will be retained by the Company and furnished to the Securities and Exchange Commission or its staff upon request.