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                                                                 Exhibit 31(b)

                                    TXU CORP.
                       Certificate Pursuant to Section 302
                         of Sarbanes - Oxley Act of 2002
                              CERTIFICATION OF CFO

         I, H. Dan Farell, Executive Vice President and Chief Financial Officer
of TXU Corp., certify that:

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

     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 12, 2004                  /s/ H. Dan Farell
                                -------------------------------------------
                                Signature: H. Dan Farell
                                Title: Executive Vice President and
                                       Chief Financial Officer