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                                                                 Exhibit 31(a)

                                 TXU GAS COMPANY
                       Certificate Pursuant to Section 302
                         of Sarbanes - Oxley Act of 2002
                              CERTIFICATION OF CEO

     I, M. S. Greene, Vice Chairman and Chief Executive of TXU Gas Company,
certify that:

1.   I have reviewed this annual report on Form 10-K of TXU Gas
     Company;

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 registrant as of, and for,
     the periods presented in this report;

4.   The registrant's other certifying officer(s) 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 registrant 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 registrant, 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.  Evaluated the effectiveness of the registrant'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

        c.  Disclosed in this report any change in the registrant's
            internal control over financial reporting that occurred during
            the registrant's most recent fiscal quarter (the registrant's
            fourth fiscal quarter in the case of an annual report) that
            has materially affected, or is reasonably likely to materially
            affect, the registrant's internal control over financial
            reporting; and

5.   The registrant's other certifying officer(s) and I have disclosed,
     based on our most recent evaluation of internal control over financial
     reporting, to the registrant's auditors and the audit committee of the
     registrant's board of directors (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
            registrant'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
            registrant's internal control over financial reporting.




Date: March 17, 2004            /s/ M. S. Greene
                         ------------------------------------------------
                         Signature: M. S. Greene
                         Title: Vice Chairman and Chief Executive