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                                                                    EXHIBIT 12.1

                             FORM 302 CERTIFICATION

      I, Mario Valcarce, certify that:

      1.    I have reviewed this annual report on Form 20-F of Enersis;

      2.    Based on my knowledge, this report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to make
the statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this report;

      3.    Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects the
financial condition, results of operations and cash flows of the company as of,
and for, the periods presented in this report;

      4.    The company's other certifying officer and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-15(e) and 15d-15(e)) for the company and have:

            (a)   Designed such disclosure controls and procedures, or caused
      such disclosure controls and procedures to be designed under our
      supervision, to ensure that material information relating to the company,
      including its consolidated subsidiaries, is made known to us by others
      within those entities, particularly during the period in which this report
      is being prepared;

            (b)   Paragraph omitted pursuant to SEC Release Nos. 33-8238 and
      34-47986

            (c)   Evaluated the effectiveness of the company's disclosure
      controls and procedures and presented in this report our conclusions about
      the effectiveness of the disclosure controls and procedures, as of the end
      of the period covered by this report based on such evaluation; and

            (d)   Disclosed in this report any change in the company's internal
      control over financial reporting that occurred during the period covered
      by the annual report that has materially affected, or is reasonably likely
      to materially affect, the company's internal control over financial
      reporting; and

      5.    The company's other certifying officer and I have disclosed, based
on our most recent evaluation of internal control over financial reporting, to
the
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company's auditors and the directors' committee of the company (or persons
performing the equivalent functions):

            (a)   All significant deficiencies and material weaknesses in the
      design or operation of internal control over financial reporting which are
      reasonably likely to adversely affect the company's ability to record,
      process, summarize and report financial information; and

            (b)   Any fraud, whether or not material, that involves management
      or other employees who have a significant role in the company's internal
      control over financial reporting.

Date: June 30, 2004

                                         /s/ Mario Valcarce
                                        ---------------------------------
                                         Mario Valcarce
                                         Chief Executive Officer


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