Exhibit 10(ss)



                          ADDITIONAL GUARANTY AGREEMENT

         THIS ADDITIONAL GUARANTY AGREEMENT, dated as of November 19, 2002 (this
"Guaranty Agreement"), is made by TXU Energy Company LLC, a Delaware limited
liability company (together with its successors and assigns, including Surviving
Entities pursuant to Section 9(b) and Replacement Guarantors pursuant to Section
21, the "Guarantor"), in favor of State Street Bank and Trust Company of
Connecticut, National Association, as Owner Trustee of the ZSF/Dallas Tower
Trust, a Delaware grantor trust (in such capacity, together with its successors
and assigns, the "Lessor"). Capitalized terms used herein have the meanings
ascribed to such terms in Section 22 (including the incorporation of the
definitions of terms that are defined in the Lease, as defined below), unless
otherwise defined elsewhere herein.

         WHEREAS, Lessor and TXU Properties Company, a Texas corporation
(together with its successors and permitted assigns, the "Lessee"), have entered
into that certain Lease Agreement dated as of February 14, 2002 (as amended,
restated, supplemented or otherwise modified from time to time, the "Lease");
and

         WHEREAS, TXU Corp., a Texas corporation (the "Parent") executed a
Guaranty Agreement dated as of February 14, 2002 (as amended, restated,
supplemented or otherwise modified from time to time, the "Parent Guaranty
Agreement"), in favor of the Lessor; and

         WHEREAS, Lessor, LaSalle Bank National Association, as Indenture
Trustee (in such capacity, together with its successors and assigns, the
"Indenture Trustee"), and First Union National Bank, as Servicer (in such
capacity, together with its successors and assigns, the "Servicer"), are parties
to that certain Indenture and Servicing Agreement dated as of February 14, 2002
(as amended, restated, supplemented or otherwise modified from time to time, the
"Indenture"); and

         WHEREAS, in connection with the transactions contemplated by the
Indenture, LaSalle Bank National Association, as Pass-Through Trustee for the
benefit of the Certificateholders (as defined below)(in such capacity, together
with its successors and assigns, the "Pass-Through Trustee"), has executed and
delivered that certain Declaration of Trust dated as of February 14, 2002 (as
amended, restated, supplemented or otherwise modified from time to time, the
"Declaration of Trust"), pursuant to which the Energy Plaza Lease Pass-Through
Trust, a Delaware grantor trust (the "Trust") was created; and

         WHEREAS, pursuant to the Assignment of Agreements (as defined in the
Indenture) and the Assignment of Lease (as defined in the Indenture), the Lessor
has assigned to the Indenture Trustee for the benefit of the registered holders
from time to time of the Secured Notes (the "Holders"), and for the benefit of
the registered holders from time to time (the "Certificateholders") of the Trust
Certificates issued pursuant to the Declaration of Trust (the "Certificates"),
all of its rights, titles, and interests in and to the Lease, the Parent
Guaranty Agreement and the other Lease Operative Documents (other than the
Excepted Payments and the Excepted Rights), including, without limitation, the
immediate and continuing right to collect and enforce any Additional Guaranty
from time to time executed pursuant to Section 9(c) of the Parent Guaranty
Agreement; and
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         WHEREAS, TXU Europe Limited, a corporation incorporated under the laws
of England and Wales ("TXU Europe"), is a subsidiary of the Parent and has filed
a petition for administration under the laws of England; and

         WHEREAS, the Lessee and the Guarantor have been notified by a Majority
in Interest of Certificateholders (as defined in the Indenture) that (i) the
taking of action by TXU Europe to authorize and effect such administration
constitutes a Lease Event of Default under Section 16.1(f)(I) of the Lease (such
Lease Event of Default, the "Existing Lease Default"), and (ii) the Existing
Lease Default caused an Event of Default under clause (e) of Section 10.1 of the
Indenture (together with the Existing Lease Default, collectively, the "Existing
Defaults"); and

         WHEREAS, the Lessee and Guarantor have requested, and
Certificateholders constituting a Majority in Interest of Certificateholders are
willing to agree to instruct the Indenture Trustee and the Servicer to waive the
Existing Defaults and to forbear from exercising remedies with respect to the
Existing Defaults, in each case subject to the terms and conditions set forth in
a letter agreement dated as of the date hereof (the "Waiver Agreement"), among
the Lessee, the Parent, the Guarantor and such Certificateholders, including,
without limitation, the condition precedent that the Guarantor execute and
deliver this Guaranty Agreement; and

         WHEREAS, the Guarantor is an indirect wholly-owned Subsidiary of the
Parent and an Affiliate of the Lessee and is engaged in related and
interdependent businesses with the Parent and the Lessee; and

         WHEREAS, the Guarantor is desirous that a Majority in Interest of
Certificateholders execute and deliver the Waiver Agreement and will receive
substantial financial and other benefits from such execution and delivery as a
member of the consolidated group of entities that includes the Parent and the
Lessee; and

         WHEREAS, the Board of Managers (or equivalent governing body) of the
Guarantor has determined that it is in the best interests of the Guarantor and
is advisable to execute and deliver this Guaranty Agreement as an Additional
Guaranty pursuant to Section 9(c) of the Parent Guaranty Agreement (and not as a
Replacement Guaranty pursuant to Section 21 of the Parent Guaranty Agreement);

         NOW THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Guarantor hereby covenants and
agrees with, and represents and warrants to the Lessor for the benefit of each
of the Lessor, the Servicer, the Trust, the Pass-Through Trustee, each other
Holder, each Certificateholder, each Indemnitee, each member of each
Indemnitee's Group, each Tax Indemnitee and each other Person to whom Base Rent
or Supplemental Rent may be payable pursuant to the Lease (together with all
successors and assigns of the foregoing, collectively, the "Beneficiaries," and
each individually, a "Beneficiary") as follows:

1.       THE GUARANTY. The Guarantor hereby irrevocably and unconditionally
         guarantees to each Beneficiary to which such obligations are owing the
         following obligations:

                (i)      the due,  punctual and full payment by the Lessee
         (whether at the stated time for payment thereof, by demand or
         otherwise) of


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         all  amounts to be paid by the Lessee pursuant to the Lease and the
         other Lease Operative  Documents,  including  but not limited to Base
         Rent, Supplemental Rent, amounts payable by the Lessee if the Lessee
         self-insures pursuant to Section 9.1(g) of the Lease, amounts payable
         by the Lessee pursuant to Sections 19.1 and 19.2 of the Lease (and
         other similar provisions of the other Lease Operative  Documents), the
         purchase price of the Property if the Lessee exercises its right to
         purchase the Property pursuant to the Lease, any applicable Make-Whole
         Premium, any Termination Value Payment, any Stipulated Loss Value
         Payment, any late charges or  penalties, interest payable on late
         charges or penalties,  all amounts  payable by the Lessee under Article
         17 of the Lease (including but not limited to liquidated  damages),
         fees,  expenses (including but not limited to the reasonable fees and
         expenses of attorneys, accountants,  experts, and advisors), or other
         similar costs (including all such amounts which would become due but
         for the operation of the automatic stay under Section 362(a) of the
         United States Bankruptcy Code, 11 U.S.C.ss.362(a), and the operation of
         Sections 502(b) and 506(b) of the United States Bankruptcy Code, 11
         U.S.C.ss.502(b) andss.506(b)); and

                (ii)   the due, prompt and faithful performance of, and
         compliance with, all other obligations, covenants, terms, conditions
         and undertakings of the Lessee contained in each Lease Operative
         Document to which the Lessee is a party in accordance with the terms
         thereof (all such obligations described in clauses (i) and (ii) above
         are herein called the "Guaranteed Obligations").

         The guaranty in the preceding sentence is an absolute, present and
         continuing guaranty of payment and not of collectability and is in no
         way conditional or contingent upon any attempt to collect from the
         Lessee, the Parent or any other Person or upon any other action,
         occurrence or circumstance whatsoever. In the event that the Lessee
         shall fail so to pay any of such Guaranteed Obligations, the Guarantor
         agrees to pay the same when due to each Beneficiary, without demand,
         presentment, protest or notice of any kind. Each default under any
         Lease Operative Document shall give rise to a separate cause of action
         hereunder and separate suits may be brought hereunder as each cause of
         action arises.

         The Guarantor also hereby agrees to pay and to indemnify and save each
         Beneficiary harmless from and against any damage, loss, cost or expense
         (including but not limited to the reasonable fees and expenses of
         attorneys, accountants, and advisors) which such Beneficiary may incur
         or be subject to as a consequence, direct or indirect, of (i) any
         breach by the Guarantor or the Lessee of any covenant, term or
         condition in, or the occurrence of any default under, this Guaranty
         Agreement or any other Lease Operative Document, together with all
         expenses resulting from the compromise or defense of any claims or
         liabilities arising as a result of any such breach or default, and
         (ii) any legal action threatened or commenced in connection with or +
         relating to this Guaranty Agreement or any other Lease Operative
         Document.

2.       OBLIGATIONS ABSOLUTE.  The obligations of the Guarantor hereunder shall
         be primary,  absolute,  irrevocable and unconditional, irrespective of
         the validity,  regularity or enforceability of any of the Indenture,
         the Lease, the Parent Guaranty Agreement or any of the other Operative
         Documents  (collectively,  the  "Transaction  Documents"),  shall


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<PAGE>

         not be subject to any counterclaim, setoff, deduction or defense based
         upon any claim the Guarantor may have against the Lessee,  the Parent,
         any Beneficiary,  or otherwise, and shall remain in full force and
         effect  without  regard to, and (subject to the  provisions of Section
         21 hereof with respect to the release of the Guarantor upon the
         substitution  of a Replacement  Guarantor  hereunder) shall not be
         released,  discharged or in any way affected by, any circumstance or
         condition  whatsoever  (whether or not the Guarantor shall have any
         knowledge or notice  thereof),  including,  without  limitation:
         (a) any  amendment,  restatement, supplement or other  modification
         from time to time to or of the Transaction Documents or any other
         instrument  referred to therein (except that the obligations of the
         Guarantor  hereunder  shall apply to the Transaction Documents or such
         other instruments as so amended, restated,  supplemented or modified)
         or any  assignment  or transfer of any thereof or of any interest
         therein,  or any furnishing, acceptance or release of any security for
         the Guaranteed  Obligations,  (b) any waiver, consent,  extension,
         indulgence or other action or inaction under or in respect of the
         Transaction  Documents;  (c) any bankruptcy, insolvency, readjustment,
         composition,  liquidation or similar proceeding with respect to the
         Lessor, the owner participant in the Lessor, the Pass-Through Trustee,
         the Parent or the Lessee or its property;  (d) any merger,
         amalgamation or consolidation of the Guarantor,  the Lessor, the
         Pass-Through  Trustee, the Parent or the Lessee into or with any other
         Person or any sale,  lease or transfer of any or all of the assets of
         the Guarantor,  the Lessor,  the  Pass-Through  Trustee, the Parent or
         the Lessee to any Person;  (e) any failure on the part of the Lessor,
         the Pass-Through  Trustee,  the Parent or the Lessee for any reason to
         comply with or perform any of the terms of any other agreement with the
         Guarantor;  or (f) any other circumstance which might otherwise
         constitute a legal or equitable  discharge or defense of a guarantor.
         The Guarantor covenants that its obligations hereunder will not be
         discharged  except  by  payment  in full of all of the  Guaranteed
         Obligations.

3.       WAIVER. The Guarantor unconditionally waives to the fullest extent
         permitted by law, (a) notice of acceptance hereof, of any action
         taken or omitted in reliance hereon and of any defaults by the Lessee
         in the  payment of any amounts due under the Transaction  Documents,
         and of any of the matters referred to in Section 2 hereof,  (b) all
         notices which may be required by statute, rule of law or otherwise to
         preserve any of the rights of any Beneficiary against the Guarantor,
         including,  without limitation, presentment to or demand for payment
         from the Lessee or the  Guarantor,  notice to the Lessee or to the
         Guarantor of default or protest for nonpayment or dishonor and the
         filing of claims with a court in the event of the  bankruptcy of the
         Lessee,  the  Parent,  the Lessor,  the owner  participant in the
         Lessor or the Pass-Through  Trustee,  (c) any right to the
         enforcement, assertion or exercise by any Beneficiary of any right,
         power or remedy conferred in this Guaranty  Agreement or the other
         Transaction  Documents,  (d) any requirement or diligence on the part
         of any  Beneficiary and (e) any other act or omission or thing or delay
         to do any other act or thing which might in any manner or to any extent
         vary the risk of the Guarantor or which might otherwise operate as a
         discharge of the Guarantor.

4.       OBLIGATIONS  UNIMPAIRED.  The Guarantor authorizes each Beneficiary,
         without notice or demand to the Guarantor and without affecting its
         obligations hereunder,  from time to time (a) to renew, compromise,
         extend,  accelerate or otherwise change the time for payment of, or
         otherwise  change the terms of, all or any part of the  Guaranteed

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<PAGE>

         Obligations  and the  Transaction Documents or any other instrument
         referred  to therein, (b) to take and hold security for the payment
         of the  Guaranteed Obligations, for the performance of the Transaction
         Documents,  for the performance of this Guaranty Agreement or
         otherwise for the indebtedness guaranteed hereby and to exchange,
         enforce,  waive and  release  any such  security,  (c) to obtain
         additional or substitute endorsers or guarantors;  (d) to exercise or
         refrain from  exercising any rights against the Lessee, the Parent,
         the Lessor,  the  Pass-Through  Trustee,  and others;  and (e) to apply
         any sums, by  whomsoever  paid or however realized, to the payment of
         any Guaranteed  Obligation  hereunder.  The Guarantor waives any right
         to require any Beneficiary to proceed against the Parent or any
         additional or  substitute endorsers or guarantors or to pursue or
         exhaust any security provided by the Lessee, the Parent, the Lessor,
         the Pass-Through  Trustee,  the Guarantor or any other Person or to
         pursue any other remedy available to any Beneficiary.

5.       SUBROGATION.  The Guarantor will not exercise against the Lessee, the
         Parent, any Additional  Guarantor (as defined in Section
         9(c)(i) of this Guaranty Agreement),  any other Additional Guarantor
         (as defined in the Parent Guaranty Agreement), any party obligated
         under any  Qualified  Letter of Credit (as defined in Section  9(c)(iv)
         of this  Guaranty  Agreement)  or any party obligated under any
         Qualified Letter of Credit (as defined in Section 9(c)(iv) of the
         Parent Guaranty  Agreement),  any rights that it may have acquired by
         way of  subrogation  under this Guaranty  Agreement,  by any payment
         made hereunder or otherwise, or accept any payment on account of such
         subrogation  rights,  or any rights of reimbursement or indemnity or
         any rights or recourse to any security for the Guaranteed Obligations
         unless and until all of the obligations,  undertakings or conditions
         to be  performed  or observed by the Lessee  pursuant to the Lease and
         by the Lessee and the  Guarantor  pursuant to the other Transaction
         Documents at the time of the Guarantor's exercise of any such right
         shall have been performed,  observed or paid in full.

         For a period of one year after the payment in full of the Guaranteed
         Obligations, the Guarantor hereby waives (x) all rights of subrogation
         which it may at any time otherwise have as a result of this Guaranty
         Agreement (whether statutory or otherwise) to the claims of the Lessor
         and the other Beneficiaries against the Lessee, the Parent or any other
         guarantor of the Guaranteed Obligations (each referred to herein as the
         "Other Party") and all contractual, statutory or common law rights of
         reimbursement, contribution or indemnity from any Other Party which it
         may at any time otherwise have as a result of this Guaranty Agreement;
         (y) any right to enforce any other remedy which the Lessor and the
         other Beneficiaries now have or may hereafter have against any Other
         Party; and (z) all claims (as such term is defined in the Bankruptcy
         Code) it may at any time otherwise have against any Other Party arising
         from any transaction whatsoever, including without limitation its right
         to assert or enforce any such claims.

6.       REINSTATEMENT OF GUARANTY.  This Guaranty Agreement shall continue to
         be effective,  or be reinstated,  as the case may be, if and to the
         extent at any time payment, in whole or in part, of any of the sums due
         to any Beneficiary  under the Lease or any other sum constituting any
         of the other Guaranteed Obligations is rescinded or must otherwise be
         restored or returned by any Beneficiary upon the insolvency,
         bankruptcy,  dissolution,


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         liquidation or reorganization  of the Lessee, the Parent,  the Lessor,
         the owner participant in the Lessor,  or the Pass-Through Trustee, or
         upon or as a result of the appointment of a custodian, receiver,
         trustee or other officer with similar powers with respect to the
         Lessee, the Parent,  the Lessor, such owner participant, the
         Pass-Through  Trustee or any substantial part of any property of any of
         the foregoing,  or otherwise, all as though such payments had not been
         made. If an event permitting Lessor or any other Beneficiary to demand
         payment of any of the Guaranteed Obligations shall at any time have
         occurred and be  continuing  and such demand shall at such time be
         prevented or the right of any Beneficiary to receive any  payment under
         any Transaction Document shall at such time be delayed or otherwise
         affected by reason of the pendency against the Lessee of a case or
         proceeding  under a bankruptcy or insolvency law, the Guarantor agrees
         that, for purposes of this Guaranty Agreement and its obligations
         hereunder,  such Guaranteed Obligation shall be deemed to have been
         demanded with the same effect as if Lessor or such other Beneficiary
         had demanded the same in  accordance  with the terms of the Transaction
         Documents, and the Guarantor shall forthwith pay such demanded amount
         and any other amounts guaranteed hereunder.

7.       PAYMENTS.  The Guarantor hereby guarantees that the Guaranteed
         Obligations  will be paid to the  Beneficiaries  in lawful currency of
         the United States of America and in immediately available funds, at the
         times and places  provided  in, and otherwise strictly in accordance
         with the terms and provisions of, the applicable Transaction Documents
         giving rise to such Guaranteed Obligations (regardless of any law,
         regulation  or decree now or hereafter in effect which might in any
         manner affect the Guaranteed Obligations, or the rights of any such
         Beneficiary  with respect  thereto as against the Lessee, or cause or
         permit to be invoked any alteration in the time, amount or manner of
         payment by the Lessee of any or all of the Guaranteed  Obligations),
         without set-off or counterclaim and free and clear of, and without
         reduction for or on account of, any present or future income, stamp or
         other taxes, levies,  imposts, duties,  charges, fees, deductions or
         withholdings now or hereafter imposed,  levied,  collected,  withheld
         or assessed by any country (or by any  political subdivision or taxing
         authority  thereof or therein) excluding taxes and other amounts for
         which the Lessee has no  obligation to pay pursuant to the Lease or the
         other Lease Operative  Documents (such  non-excluded  taxes and other
         amounts being called  "Taxes").  If any Taxes are required to be
         withheld for any amount payable to any  Beneficiary under this Guaranty
         Agreement,  the amounts so payable to the applicable Beneficiary shall
         be increased to the extent necessary to yield to such Beneficiary
         (after payment of all Taxes) interest or any such other amounts at the
         rates or in the amounts specified in the Transaction Documents.

8.       RANK OF GUARANTY. The Guarantor agrees that its obligations under this
         Guaranty Agreement shall rank at least pari passu with all other
         unsecured senior obligations of the Guarantor now or hereafter
         existing.

9.       ADDITIONAL COVENANTS OF THE GUARANTOR.

                (a) General. So long as the Guaranteed Obligations are
                    --------
         outstanding or the Transaction Documents shall remain in effect, the
         Guarantor agrees that, unless the Majority in Interest of the
         Certificateholders otherwise consents in writing:

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        (i)      Maintenance  of Existence,  Etc. Subject to Section 9(b), the
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         Guarantor will at all times do or cause to be done all things necessary
         to maintain and preserve its existence as a limited liability company,
         and maintain,  preserve and renew its and its Subsidiaries' licenses,
         patents and franchises material to the conduct of the business of
         the  Guarantor  and such  Subsidiaries taken as a whole, provided that
         nothing  contained in this Section 9(a)(i) shall (A) require the
         Guarantor or any such Subsidiary to maintain, preserve or renew any
         license, patent or franchise  not necessary or desirable in the conduct
         of its business, or (B) prohibit the Guarantor from terminating the
         corporate existence of a Subsidiary if in the reasonable opinion of the
         Guarantor such termination is in the best interests of the Guarantor
         and is not disadvantageous to any Beneficiary.

        (ii)     Financial Statements, Etc. The Guarantor will furnish to the
                 -------------------------
         Lessor and to each Certificateholder, as applicable:

                        (A) as soon as publicly available, and in any event
                 within the earlier of (1) 120 days after the end of each
                 fiscal year of the Guarantor or (2) the date by which the
                 annual financial statements of the Guarantor are required to be
                 delivered pursuant to its primary revolving credit facility, a
                 consolidated balance sheet of the Guarantor and its
                 consolidated Subsidiaries as at the end of such fiscal year
                 and the related consolidated statements of operations and
                 sources of funds of the Guarantor and its consolidated
                 Subsidiaries for such fiscal year, prepared in conformity with
                 GAAP (except as disclosed in the notes thereto) and reported
                 on by independent accountants of recognized national standing;
                 provided, that delivery of copies of either the annual report
                 on Form 10-K of the Guarantor for such annual period or, in
                 lieu  thereof, a report on Form 8-K of Guarantor's direct
                 parent, TXU US Holdings Company, a Texas corporation
                 ("Holdings"), filed with the Securities and Exchange
                 Commission shall be deemed to satisfy the requirements of this
                 clause (A) with respect to consolidated financial statements
                 if such financial statements are included in such report;

                        (B) as soon as publicly available, and in any event
                 within the earlier of (1) 60 days after the end of each quarter
                 (except the last quarter)of each fiscal  year of the Guarantor
                 or (2) the date by which the quarterly financial statements of
                 the Guarantor are required to be delivered pursuant to its
                 primary revolving credit facility, a consolidated balance sheet
                 of the Guarantor and its consolidated Subsidiaries as at the
                 end of such quarter and the related consolidated statements of
                 operations and sources of funds of the Guarantor and its
                 consolidated Subsidiaries for such quarter and for the period
                 from the beginning of such fiscal year to the end of such
                 quarter, in each case setting forth comparative figures for the
                 related periods in the prior fiscal year, certified by the
                 chief financial officer, the chief accounting officer or the
                 treasurer of the Guarantor to have been prepared in accordance
                 with GAAP (except as disclosed in the notes


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                thereto and subject to normal year-end adjustments); provided,
                that delivery of copies of either the quarterly report on Form
                10-Q of the Guarantor for such quarterly period or, in lieu
                thereof, a report on Form 8K of Holdings, filed with the
                Securities and Exchange Commission shall be deemed to satisfy
                the requirements of this clause (B) with respect to
                consolidated financial statements if such financial statements
                are included in such report;

                        (C) concurrently with the delivery each year of the
                financial statements furnished pursuant to Section 9(a)(ii)(A),
                an officer's certificate of the Guarantor certifying that the
                signer has reviewed or caused to be reviewed by persons under
                his supervision, the relevant terms of this Guaranty Agreement
                and has made, or caused to be made under his supervision, a
                review of the transactions and financial condition of the
                Guarantor and its consolidated Subsidiaries during the preceding
                year, and that such review has not disclosed the existence
                during such period,  nor does the signer have knowledge of the
                existence as at the date of such certificate, of a Lease
                Default, a Lease Event of Default or a default hereunder, or of
                any other default with respect to the Guaranteed Obligations or,
                if any such a default existed or exists, specifying the nature
                and period of existence thereof and what action the Guarantor
                has taken or is taking or proposed to take with respect thereto;

                        (D) with reasonable promptness, such other information
                relating to the Guarantor, any of its Material Subsidiaries, or
                the Lessee that any Certificateholder may from time to time
                reasonably request and that the Guarantor may furnish without
                violating applicable securities laws (taking into account the
                Certificateholders' confidentiality obligations under paragraph
                9D of the Certificate Purchase Agreement pursuant to which the
                Certificates were issued); and

                       (E) upon the request of any Certificateholder, provide
                such Certificateholder, and any qualified institutional buyer
                designated by such Certificateholder, such financial and other
                information as such Certificateholder may reasonably determine
                to be necessary in order to permit compliance with the
                information requirements of Rule 144A (as such term is defined
                in the Indenture) in connection with the resale of the Trust
                Certificates (as such term is defined in the Indenture), except
                at such times as the Guarantor is subject to the reporting
                requirements of section 13 or 15(d) of the Exchange Act (as such
                term is defined in the Indenture)(for the purpose of this clause
                (E), the term "qualified institutional buyer" shall have the
                meaning specified in Rule 144A).

                (iii)   Inspections, Etc. The Guarantor will permit any
                        -----------------
authorized representative of Lessor or any Certificate holder, upon reasonable
prior notice and at the expense of the Guarantor at such times as a Lease
Default or a Lease Event of Default shall exist and otherwise at the expense of
the Lessor or


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         such Certificateholder, as the case may be, to visit and discuss with
         the Guarantor's officers the financial condition of the Guarantor and
         the Guarantor's ability to comply with its obligations hereunder, all
         at such reasonable times and intervals as Lessor or such
         Certificateholder may request.

   (b)      Merger, Consolidation. The Guarantor shall not consolidate with, or
merge with or into, any other Person or convey, transfer or lease all or
substantially all of its assets as an entirety (whether by one transaction or a
series of related transactions) to any Person, unless each of the following
conditions shall be satisfied:

    (i)     the successor entity formed by such consolidation, the survivor of
            such merger (including the Guarantor) or the successor entity which
            acquires by conveyance, transfer or lease all or substantially all
            of the assets of the Guarantor as an entirety (each of the foregoing
            being referred to as the "Surviving Entity") shall be a Solvent
            entity organized and existing under the laws of the United States
            of America, any State thereof or the District of Columbia and at
            least $5,000,000,000 of the Surviving Entity's consolidated assets
            shall be within the United States;

     (ii)   the Surviving Entity (if not the Guarantor), shall expressly assume
            in writing by instrument or instruments reasonably satisfactory to
            the Majority in Interest of the Certificateholders, in scope, form
            and legal effect, the due and punctual payment, performance and
            observance of all obligations of the Guarantor under this Guaranty
            Agreement, with the same effect as if such entity had originally
            been named Guarantor herein or had been a party hereto;

      (iii) prior to and immediately after giving effect to such transaction,
            no Lease Default or Lease Event of Default shall exist;

      (iv)  the Surviving Entity shall have delivered to the Lessor an officer's
            certificate stating that such consolidation, merger, conveyance,
            transfer or lease and the assumption agreement required by clause
            (ii)above comply with the provisions of this Section 9(b);

      (v)   (A) in the case of any consolidation, merger, conveyance, transfer
            or lease with an entity  that is an  Affiliate  of the  Guarantor
            prior to giving effect to such transaction, then immediately after
            giving  effect to such transaction the tangible net worth
            (calculated in accordance  with GAAP) of the Successor Entity shall
            be equal to or greater than $3,000,000,000, (B) in the case of any
            consolidation,  merger, conveyance, transfer or lease with any
            Affiliate of the Guarantor to which the foregoing subclause (A) does
            not apply,  the Guarantor shall have first obtained the prior
            written consent of the Lessor and the Majority in Interest of the
            Certificateholders, and (C) in the case of any consolidation,
            merger, conveyance, transfer or lease with any Person that is not
            an Affiliate of the Guarantor prior to giving

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<PAGE>

            effect to such transaction, either (1) the tangible net worth
            (calculated in accordance with GAAP) of the Surviving Entity
            immediately after giving effect to such transaction shall be equal
            to or greater than the greater of $3,000,000,000 and the tangible
            net worth (calculated in accordance with GAAP) of the Guarantor
            immediately prior to such transaction or (2) the Guarantor shall
            have first obtained the prior written consent of the Lessor and the
            Majority in Interest of the Certificateholders;

(vi)        immediately after giving effect to such transaction, the Surviving
            Entity shall have Acceptable Debt Ratings from Standard & Poor's
            and Moody's that in each case are at least as high as the Debt
            Ratings of the Guarantor immediately prior to the date of such
            transaction; and

(vii)       in the case of any such consolidation, merger, conveyance, transfer
            or lease in which the Guarantor is not the Surviving Entity, the
            Surviving Entity shall have caused to be delivered to Lessor and
            the Indenture Trustee an opinion of counsel reasonably acceptable to
            the Majority in Interest of the Certificateholders, to the effect
            that all agreements or instruments effecting the assumption
            referred to in clause (ii) above are enforceable in accordance
            with their terms and comply with the terms of the Transaction
            Documents.

            Upon any consolidation or merger, or any conveyance, transfer or
lease of all or substantially all of the assets of the Guarantor as an
entirety, in accordance with this Section 9(b), in a transaction in which the
Guarantor is not the Surviving Entity, the Surviving Entity shall succeed to,
and be substituted for, the Guarantor under this Guaranty Agreement, with the
same effect as if such successor had been named as the Guarantor herein.

(c)      Ratings  Decline.  If any Ratings Decline occurs, the Guarantor shall
         ----------------
provide written notice thereof to the Lessor, the Indenture Trustee, the
Servicer and each  Certificateholder  within 10 days thereafter and shall cause
an Additional Guaranty or a Qualified Letter of Credit satisfying the
requirements set forth below to be provided to the Indenture Trustee (as
assignee of the Lessor's rights under the Lease) within 30 days after such
Ratings Decline. Any failure to provide such Additional Guaranty or Qualified
Letter of Credit  within such 30-day period shall constitute a Lease Event of
Default.  In the event that the Guarantor regains Acceptable Debt Ratings, and
provided that no Lease Default or Lease Event of Default shall exist at the
time of either such notice or such release,  the Guarantor may, upon at least
thirty (30) days' prior written notice to the Lessor, the Indenture Trustee,
the Servicer and each Certificateholder, obtain the release of such Additional
Guaranty or Qualified Letter of Credit,  as the case may be, by delivering to
the Lessor, the Indenture  Trustee, the Servicer and each Certificateholder
satisfactory evidence that the Guarantor has regained Acceptable Debt Ratings.
In the event of a Ratings Decline occurring after such release, the provisions
of this Section 9(c) requiring the delivery of an Additional Guaranty or a
Qualified  Letter of Credit shall again apply.  In addition, at any time that
an Additional Guaranty or a Qualified Letter of Credit shall be in effect,  the
Guarantor may, upon at least  thirty (30) days' prior written


                                       10
<PAGE>
notice to the Lessor, the Indenture Trustee (as assignee of the Lessor's rights
under the Lease), the Servicer and each Certificateholder, substitute an
Additional Guaranty or a Qualified Letter of Credit for the Additional Guaranty
or the Qualified Letter of Credit then outstanding pursuant hereto, provided
that no Lease Default or Lease Event of Default shall exist at the time of any
such notice or substitution.

        (i)      "Additional Guaranty" shall mean a guaranty agreement
                  that has been duly executed and delivered by an
                  Acceptable Guarantor (an "Additional Guarantor") and
                  is in a form substantially identical to this Guaranty
                  Agreement (with appropriate references revised to
                  reflect the identity and form of business
                  organization of the Additional Guarantor but with the
                  deletion of Section 21 and references to a
                  Replacement Guarantor). Without limitation of the
                  foregoing, any Additional Guaranty shall include
                  credit enhancement requirements identical to those
                  set forth in this Section 9(c) to protect the
                  Beneficiaries in the event a Ratings Decline occurs
                  with respect to any Debt Rating of such Additional
                  Guarantor.

        (ii)      "Acceptable Guarantor" shall mean a Solvent entity
                  organized and existing under the laws of the United
                  States of America, any State thereof or the District
                  of Columbia that satisfies all of the following
                  criteria:

                        (A)  at least 35% of such entity's consolidated assets,
                  properties and operations shall be within the United States;

                        (B)  the tangible net worth (calculated in accordance
                  with GAAP from audited financial statements reasonably
                  acceptable to the Majority in Interest of Certificateholders
                  and provided to the Indenture Trustee, the Servicer and the
                  holders of the Trust Certificates prior the delivery of such
                  Additional Guaranty) of such entity must be equal to or
                  greater than $3,000,000,000; and

                        (C)  such entity must have Acceptable Debt Ratings.

        (iii)     "Qualified Letter of Credit" shall mean an uncollateralized,
                  irrevocable, standby letter of credit issued by an Acceptable
                  Bank, in form and substance satisfactory to the Majority in
                  Interest of Certificateholders (in their sole and exclusive
                  judgment exercised in good faith), that satisfies all
                  of the following criteria:

                        (A) the Servicer, acting on behalf of the Indenture
                  Trustee, as assignee of the Lessor's rights under the
                  Lease, shall be the initial beneficiary of such
                  letter of credit;

                        (B) such letter of credit shall authorize the Servicer
                  to draw on the Issuing Bank from time to time immediately
                  available funds in an aggregate amount which at all times
                  shall be at least equal to the greater of (1) the aggregate
                  Base Rent remaining to be paid over the remainder of the
                  scheduled Base Term (determined initially on the date of the
                  issuance


                                       11
<PAGE>

                  thereof without discounting) and (2) the largest
                  Stipulated Loss Value Payment payable by the Lessee
                  over the remainder of the scheduled Base Term;

                         (C) such letter of credit shall provide that it may be
                  drawn as provided in paragraph (vi) below, with each drawing
                  under this clause (C) or under the foregoing clause (B)
                  being made by presentation, at an office of the issuing bank,
                  in person, via courier or other delivery service, on or before
                  the stated expiry date thereof, of a certificate that (I)
                  identifies the letter of credit with respect to which such
                  certificate is being presented, (II) identifies the
                  event permitting such drawing and certifies that such
                  event has occurred, and (III) identifies the amount
                  being drawn thereunder;

                         (D) such letter of credit shall have a stated expiry
                  date which is at least one year from date of the issuance
                  thereof and, if such expiry date is prior to the end of the
                  Base Term,  which shall be automatically extended pursuant to
                  the  terms of such letter of credit for a period of at least
                  one year from the date of such  expiration unless the issuer
                  thereof shall, not later than 30 days prior to the stated
                  expiry date,  provide written notice to the Servicer, acting
                  on behalf of the Indenture Trustee (as assignee of the
                  Lessor's rights under the  Lease), in bold face type
                  identifying such letter of credit with particularity, stating
                  that such notice is a "Notice of Letter of Credit Expiration"
                  and that such letter of credit  shall  expire upon the expiry
                  date stated in such notice and in such letter of credit; and

                         (E) such letter of credit shall be transferable by the
                  beneficiary thereof in its entirety, without any fee
                  applicable to such transfer that is required to be
                  paid by any such transferor or transferee, to any
                  successor Servicer, acting on behalf of the Indenture
                  Trustee (as assignee of the Lessor's rights under the
                  Lease) pursuant to the terms of the Indenture.

        (iv)      "Acceptable Bank" shall mean any bank or trust company (i)
                  which is organized under the laws of the United States of
                  America or any State thereof, (ii) which has capital, surplus
                  and undivided profits aggregating at least $1,000,000,000,
                  and (iii) which has a Debt Rating issued by Standard & Poor's
                  of at least of at least AA- and a Debt Rating issued by
                  Moody's of at least Aa3 (or such bank or trust company must
                  have either of such Debt Ratings in the event that either
                  Moody's or Standard & Poor's (including their respective
                  successors) shall have ceased to exist).

        (v)       Any Additional Guaranty shall be delivered with (x)
                  legal opinions (in form and substance equivalent to
                  those opinions delivered with respect to this
                  Guaranty Agreement but consistent with the structure
                  of the Additional Guarantor), and (y) such
                  certificates, documents or instruments as the
                  Indenture Trustee, the Servicer or any
                  Certificateholder may reasonably request to provide
                  such Persons the types of legal opinions and

                                       12
<PAGE>

                  such certificates, documents or instruments it received
                  with respect to this Guaranty Agreement, each of which
                  deliveries shall be in form and substance satisfactory to the
                  Indenture Trustee, the Servicer and each Certificateholder
                  (in their sole and exclusive judgments exercised in good
                  faith).

        (vi)      With respect to any Qualified Letter of Credit, the
                  Servicer on behalf of the Indenture Trustee (as
                  assignee of the Lessor's rights under the Lease)
                  shall be permitted thereunder,

                        (A) from time to time, if the Lessee and the Guarantor
                  fail to make any payment of Base Rent on the applicable Rent
                  Payment Date, to draw upon such Qualified Letter of Credit in
                  an amount equal to the amount of Base Rent that is not paid
                  on such Rent Payment Date;

                        (B) if any event occurs that requires the Lessee to make
                  a Stipulated Loss Value Payment pursuant to the Lease
                  and the Lessee and the Guarantor fail to make such
                  payment, to draw upon such Qualified Letter of Credit
                  in the amount of the Stipulated Loss Value Payment
                  calculated as of the business day following the date
                  of such occurrence;

                        (C) if any Lease Event of Default results in an
                  acceleration of the Base Rent payable under the
                  Lease, to draw upon such Qualified Letter of Credit
                  in an amount equal to the maximum remaining amount
                  available to be drawn thereunder; and

                        (D) if thirty (30) or fewer days remain prior to the
                  stated expiry date of such Qualified Letter of Credit, the
                  issuer thereof has given the notice of non-extension referred
                  to in clause (D) of paragraph (iii) above, and the Servicer on
                  behalf of the Indenture Trustee (as assignee of the Lessor's
                  rights under the Lease) has not received a Qualified Letter
                  of Credit or an Additional Guaranty to replace such
                  Qualified Letter of Credit, to draw upon such Qualified Letter
                  of Credit in an amount equal to the maximum remaining amount
                  available to be drawn thereunder.

                        The proceeds from each drawing under the Qualified
                  Letter of Credit shall be deposited in the Rent Collection
                  Account and applied pursuant to the provision of the Indenture
                  that would have applied in the event that the payment had been
                  made by the Lessee itself under the circumstances under the
                  Lease giving rise to such payment; provided, however, that
                  the proceeds from any drawing under clause (D) above
                  shall, within five (5) Business Days following the
                  Servicer's receipt of the proceeds of such drawing,
                  be applied (to the extent of such proceeds) by the
                  Indenture Trustee to the purchase of United States
                  Treasury securities identified to the Indenture
                  Trustee by the Guarantor, that are non-callable, that
                  mature as close as possible prior to each succeeding
                  Rent Payment Date and that are in the respective
                  amounts of Base Rent payable on such

                                       13
<PAGE>

                  dates. Upon the receipt by the Servicer on behalf of the
                  Indenture Trustee (as assignee of the Lessor's rights under
                  the Lease) of the proceeds from a drawing under the Qualified
                  Letter of Credit pursuant clause (A), (B) or (C) above, the
                  obligation of the Lessee or the Guarantor to make the
                  corresponding payment under the Lease shall be deemed
                  satisfied, but only to the extent of the amount of such
                  proceeds and without (a)curing any Lease Default or Lease
                  Event of Default relating to such corresponding payment under
                  the Lease except as provided in the final sentence of
                  this paragraph or (b) affecting the obligation of the
                  Lessee or the Guarantor to make any other payment of
                  Base Rent, Supplemental Rent, Stipulated Loss Value Payment,
                  Termination Value Payment or any other amount at any time
                  payable under the Lease or this Guaranty Agreement, as the
                  case may be. Upon the purchase by the Indenture Trustee of the
                  United States Treasury securities referred to in the first
                  sentence of this paragraph, the execution of a supplement to
                  the Indenture to accomplish the defeasance of certain
                  obligations of the Lessee that is to be effected by such
                  purchase, the delivery (x) by the Lessee of a tax opinion
                  relating to the defeasance and (y) by the Issuer of a
                  security agreement and a legal opinion relating to such
                  securities and the defeasance effected by the
                  purchase thereof (which supplement to the Indenture,
                  security agreement and legal opinions must be
                  satisfactory in form, scope and substance to the
                  Indenture Trustee and the Majority in Interest of
                  Certificateholders, acting through the Pass-Through
                  Trustee(as such terms are defined in the Indenture)),
                  the Guarantor will no longer be obligated to provide
                  an Additional Guaranty or a Qualified Letter of
                  Credit at such times as it does not maintain
                  Acceptable Debt Ratings (and no Lease Default or
                  Lease Event of Default thereafter shall result solely
                  from its failure to maintain Acceptable Debt Ratings)
                  and the Lessee will be released from its obligation
                  to pay Base Rent during the Base Term (to the extent
                  of the principal amount of such securities at the
                  respective maturities thereof), but without affecting
                  the obligation of the Lessee or the Guarantor to make
                  any other payment of Base Rent or any payment of
                  Supplemental Rent, Stipulated Loss Value Payment, Termination
                  Value Payment or any other amount at any time payable under
                  the Lease or this Guaranty Agreement, as the case may be,
                  except to the extent of the net proceeds actually realized by
                  the Indenture Trustee at the respective maturities of such
                  securities or upon the sale or other disposition of such
                  securities pursuant to such security agreement and the other
                  Debt Documents under the circumstances provided therein for
                  such sale or other disposition. To the extent that the
                  proceeds from any drawing under clause (A) or (B) above are
                  received by the Servicer on behalf of the Indenture Trustee
                  (as assignee of the Lessor's rights under the Lease) before
                  the expiration of the applicable grace period under
                  Section 16.1 (a) of the Lease, then such receipt shall cure
                  the Lease Default that resulted from the failure of the
                  Lessee to make the payment in question under the Lease.

                                       14
<PAGE>

        (vii)     For avoidance of doubt, an Additional Guaranty or Qualified
                  Letter of Credit delivered with respect to a Ratings Decline
                  may be used to satisfy both the provisions of this Section
                  9(c) and the provisions of Section 9(c) of the Parent Guaranty
                  Agreement (or any Replacement Parent Guaranty) with respect to
                  such Ratings Decline.

10.  REPRESENTATIONS AND WARRANTIES OF THE GUARANTOR.

     The Guarantor represents and warrants as follows:

             (a)  Organization. Good Standing and Location. The Guarantor is (i)
     a limited liability company duly organized, validly existing and in
     good standing under the laws of the State of Delaware, (ii) duly
     qualified and authorized to do business and in good standing in every
     other jurisdiction where the nature of its business requires such
     qualification and (iii) has all requisite limited liability company
     power and authority, and all governmental licenses and permits, to own
     and operate its properties and to carry on its businesses as presently
     conducted. The Guarantor has the requisite limited liability company
     power to enter into and perform its obligations under this Guaranty
     Agreement.

             (b)  Authorization and Enforceability of Guaranty Agreement. The
                  ------------------------------------------------------
     execution, delivery and performance of this Guaranty Agreement have been
     duly authorized by all necessary limited liability company action on the
     part of the Guarantor. This Guaranty Agreement has been duly and
     validly executed and delivered and constitutes the legal, valid and
     binding obligation of the Guarantor, enforceable against it in
     accordance with its terms, subject to (i) applicable bankruptcy,
     insolvency, moratorium, reorganization, receivership and similar laws
     affecting the rights and remedies of creditors generally, and (ii)
     general principles of equity (regardless of whether such enforceability
     is considered in a proceeding in equity or at law).

            (c)  Consents and Approvals;  No Breach;  Adequate  Consideration.
                 ------------------------------------------------------------
     All consents,  approvals,  licenses and  authorizations of, and filings and
     registrations with, any Governmental  Authority  required under Applicable
     Laws for the execution,  delivery and performance of this Guaranty
     Agreement have been obtained or made and are in full force and effect.
     The execution, delivery and performance of this Guaranty  Agreement does
     not and will not violate the provisions of any Applicable Laws, and does
     not and will not result in the breach of, or constitute a default or
     require  any consent under,  any material agreement, instrument, or
     document to which it is a party or by which it or any of its property may
     be bound or affected.  By virtue of its relationship with the Lessee and
     the Parent, the execution, delivery and performance of this Guaranty
     Agreement is for the direct benefit of Guarantor and it has received
     adequate consideration for this Guaranty Agreement.

11.  NOTICES. Unless otherwise specifically provided herein, all notices,
     consents, directions, approvals,  instructions,  requests and other
     communications required or permitted by the terms hereof shall be in
     writing,  and any such communication shall become effective  when received,
     addressed in the following manner: (a) if to the  Guarantor, to TXU Energy
     Company LLC, Attention: Treasurer, 1601 Bryan St., Dallas, Texas  75201,
     with a copy to Hunton &  Williams,  1601  Bryan  Street,  Dallas, Texas

                                       15
<PAGE>

     75201,  or (b) if to  Lessor or any  other  Beneficiary,  to the address
     of Lessor set forth in the Lease and to the address of each other
     Beneficiary as set forth in the Transaction Documents or as otherwise
     provided to Guarantor by such other  Beneficiary;  provided,  however,
                                                        --------   -------
     that any such addressee may change its address for communications by notice
     given aforesaid to the other parties hereto.

12.  CONSTRUCTION. The section and subsection headings in this Guaranty
     Agreement are for convenience of reference only and shall neither be
     deemed to be a part of this Guaranty Agreement nor modify, define,
     expand or limit any of the terms or provisions hereof. All references
     herein to numbered sections, unless otherwise indicated, are to
     sections of this Guaranty Agreement. Words and definitions in the
     singular shall be read and construed as though in the plural and vice
     versa, and words in the masculine, neuter or feminine gender shall be
     read and construed as though in either of the other genders where the
     context so requires.

13.  SEVERABILITY. If any provision of this Guaranty Agreement, or the
     application thereof to any Person or circumstances, shall, for any
     reason or to any extent, be invalid or unenforceable, such invalidity
     or unenforceability shall not in any manner affect or render invalid or
     unenforceable the remainder of this Guaranty Agreement, and the
     application of that provision to other Persons or circumstances shall
     not be affected but, rather, shall be enforced to the extent permitted
     by applicable law.

14.  SUCCESSORS. The terms and provisions of this Guaranty Agreement shall
     be binding upon the Guarantor and its successors and permitted assigns
     and shall inure to the benefit of the Lessor, the other Beneficiaries
     and their respective successors, transferees and assigns. Without
     limitation of the foregoing sentence, the Guarantor acknowledges that
     the Lessor has assigned to the Indenture Trustee of all of its rights,
     titles, and interests in and to this Guaranty Agreement and the other
     Lease Operative Documents (other than the Excepted Payments and
     Excepted Rights) pursuant to the Assignment of Lease and Assignment of
     Agreements.

15.  ENTIRE AGREEMENT; AMENDMENT. This Guaranty Agreement expresses the
     entire understanding of the subject matter hereof, and all other
     understandings, written or oral, are hereby merged herein and
     superseded. No amendment of or supplement to this Guaranty Agreement,
     or waiver or modification of, or consent under, the terms hereof shall
     be effective unless in writing and signed by the Guarantor, the
     Indenture Trustee, the Lessor, and each Certificateholder; provided,
     however, that the provisions of Section 9 hereof may be amended or
     waived if such amendment or waiver is in writing and signed by the
     Guarantor, the Indenture Trustee, the Lessor, and Certificateholders
     constituting a Majority in Interest of the Certificateholders.

16.  TERM OF GUARANTY AGREEMENT. Subject to Section 6, this Guaranty
     Agreement and all guarantees, covenants and agreements of the Guarantor
     contained herein shall continue in full force and effect and shall not
     be discharged until such time as all of the Guaranteed Obligations
     shall be paid or otherwise discharged in full.

                                       16
<PAGE>

17.  SURVIVAL. All warranties, representations and covenants made by the
     Guarantor herein or in any certificate or other instrument delivered by
     it or on its behalf under this Guaranty Agreement shall be considered
     to have been relied upon by each Beneficiary and shall survive the
     execution and delivery of this Guaranty Agreement, regardless of any
     investigation made by any Beneficiary or on its behalf.

18.  FURTHER ASSURANCES. The Guarantor hereby agrees to execute and deliver
     all such instruments and take all such action as the Lessor may from
     time to time reasonably request in order to effectuate fully the
     purposes of this Guaranty Agreement.

19.  GOVERNING LAW. This Guaranty Agreement has been executed and delivered
     in the State of New York and shall be governed by, construed and
     enforced in all respects in accordance with the laws of the State of
     New York applicable to contracts made and to be performed entirely
     therein, without regard to principles of conflicts of laws.

20.  SUBMISSION TO JURISDICTION.  The Guarantor hereby irrevocably submits
     itself to the nonexclusive  jurisdiction of the Supreme Court of the State
     of New York,  New York  County, of the United States of America and to the
     jurisdiction  of the United States District Court for the Southern District
     of New York, for the purpose of any suit, action or other proceeding
     arising out of, or relating to, this Guaranty Agreement or the subject
     matter hereof, and hereby waives, and agrees not to assert, by way of
     motion, as a defense or otherwise, in any such suit, action or proceedings,
     (i) any  claim  that it is not personally subject to the jurisdiction of
     the above-named courts for any reason whatsoever, that such suit, action
     or proceeding is brought in an inconvenient forum or that the venue of
     such suit, action or proceeding is improper and (ii) any right which it
     may have to a trial by a jury.

          The Guarantor hereby agrees that the submission to jurisdiction
     referred to in this Section 20 shall not limit in any manner the
     rights of any of the Certificateholders to take proceedings
     against the Guarantor in some other court of competent jurisdiction
     whether within or outside the United States.

21.  REPLACEMENT OF GUARANTOR. If no Lease Default, Lease Event of Default
     or Event of Default shall exist at the time of either such request or
     such release, then following the written request of the Guarantor to
     the Indenture Trustee and the Certificateholders at least thirty (30)
     days prior to the requested date on which the Guarantor is to be
     released from its obligations under this Guaranty Agreement, the
     Guarantor shall be released from further liability under this Guaranty
     Agreement upon its being replaced by a Replacement Guarantor that
     satisfies all the conditions contained in the definition of such term
     set forth in Section 22.

22.  DEFINITIONS. As used herein, the terms listed below shall have the
     definitions specified below. Capitalized terms used but not otherwise
     defined in this Guaranty Agreement shall have the meanings ascribed to
     such terms in the Lease.

                  "Acceptable Debt Ratings" shall mean, with respect to any
     Person, that such Person has a Debt Rating

                                       17
<PAGE>

     issued by Moody's of at least Baa3 or better and a Debt Rating from
     Standard & Poor's of at least BBB-. If any of the foregoing rating
     categories used by Moody's or Standard & Poor's is revised or designated
     differently (such as by changing letter designations to different letter
     designations or to numerical designations), then the references herein to
     such rating shall be changed to the revised or redesignated rating for
     which the standards are closest to, but not lower than, the standards at
     the date hereof for the rating which has been revised or redesignated. If
     either(but not both) of Moody's or Standard & Poor's (including their
     respective successors) shall cease to exist or shall cease to issue
     Debt Ratings generally, then "Acceptable Debt Ratings" shall consist
     solely of the above-required Debt Rating issued by whichever of Moody's
     and Standard & Poor's shall remain in existence or shall continue to
     issue Debt Ratings generally, as the case may be.

               "Debt Rating" shall mean, with respect to any Person, the
     rating applicable to such Person's senior, unsecured non-credit
     enhanced long-term indebtedness for borrowed money issued by Standard &
     Poor's or Moody's, as applicable. A Debt Rating, whether public or
     private, issued by Standard & Poor's or Moody's shall be deemed to be
     in effect on the date of announcement or publication by Standard &
     Poor's or Moody's, as the case may be, of such Debt Rating or, in the
     absence of such announcement or publication, on the effective date of
     such Debt Rating and will remain in effect until the date when any
     change in such Debt Rating is deemed to be in effect.

              "Event of Default" shall have the meaning specified in the
     Indenture.

              "Issuing Bank" shall mean the bank that issues a Qualified
     Letter of Credit.

              "Majority in Interest of the Certificateholders" shall mean
     the "Majority in Interest of the Holders" as such term is defined in
     the Declaration of Trust.

              "Material Subsidiary" shall mean any Subsidiary of the
     Guarantor which (i) has contributed more than 5% of the Guarantor's
     consolidated net income (calculated in accordance with GAAP) for the
     fiscal year then most recently ended or (ii) owns assets which
     constitute more than 5% of the Guarantor's consolidated assets
     (calculated in accordance with GAAP) as of the last day of the fiscal
     year most recently ended.

               "Ratings Decline" shall mean the existence or occurrence of
     any of the following events: (i) the Guarantor shall cease to have
     Acceptable Debt Ratings; or (ii) either Moody's or Standard & Poor's ,
     or both, shall not have in effect a Debt Rating with respect to the
     Guarantor for any reason whatsoever except the failure of either, but
     not both, of Moody's and Standard & Poor's (including their successors)
     to continue in existence or to issue Debt Ratings generally, as the
     case may be; provided, that, neither the existence nor the occurrence
     of the foregoing events shall cause a Ratings Decline if (x) the Parent
     Guaranty Agreement or a Replacement Parent Guaranty is in full force
     and effect and enforceable against the Parent or the applicable
     Replacement Parent Guarantor, as the case may be, in accordance with
     its terms, and (y) the Parent or the applicable Replacement Parent
     Guarantor, as the case may be, has Acceptable Debt Ratings.

                                       18
<PAGE>

               "Replacement Guarantor" shall mean a Person that satisfies the
     requirements set forth in clauses (i), (ii) (which requirement shall be
     satisfied by the execution and delivery by such Person of a guaranty
     agreement that is in form identical to this Guaranty Agreement, with
     appropriate references revised to reflect the identity and form of
     business organization of such Person), (iv), (v)(A), (vi) and (vii) of
     Section 9(b) of this Guaranty Agreement, recognizing that such Person
     is to replace the Guarantor hereunder as the result of a transaction
     that is not subject to such Section but is instead subject to Section
     21; provided, that no Person may be both a Replacement Guarantor
     hereunder and a Replacement Parent Guarantor pursuant to Section 21 of
     the Parent Guaranty Agreement.

              "Replacement Parent Guarantor" shall mean Replacement
     Guarantor (as defined in Section 22 of the Parent Guaranty Agreement).

              "Replacement Parent Guaranty" shall mean a guaranty agreement
     delivered in replacement and substitution for the Parent Guaranty
     Agreement in accordance with Section 21 thereof.

              "Secured Notes" shall have the meaning given to such term in
     the Indenture.

              "Solvent" shall mean, when used with respect to any Person,
     means that, as of any date of determination, (a) the amount of the
     "fair value" or "present fair saleable value" of the assets of such
     Person (on a going-concern basis) will, as of such date, exceed the
     amount of all "liabilities of such Person, contingent or otherwise," as
     of such date, as such quoted terms are determined in accordance with
     applicable federal and state laws governing determinations of the
     insolvency of debtors, (b) such fair value or present fair saleable
     value of the assets of such Person (on a going-concern basis) will, as
     of such date, be greater than the amount that will be required to pay
     the liability of such Person on its debts as such debts become absolute
     and matured, (c) such Person will not have, as of such date, an
     unreasonably small amount of capital with which to conduct its
     business, and (d) such Person will be able to pay its debts as they
     mature. For purposes of this definition, (i) "debt" means liability on
     a "claim," (ii) "claim" means any (x) right to payment, whether or not
     such a right is reduced to judgment, liquidated, unliquidated, fixed,
     contingent, matured, unmatured, disputed, undisputed, legal, equitable,
     secured or unsecured or (y) right to an equitable remedy for breach of
     performance if such breach gives rise to a right to payment, whether or
     not such right to an equitable remedy is reduced to judgment, fixed,
     contingent, matured or unmatured, disputed, undisputed, secured or
     unsecured and (iii) unliquidated, contingent, disputed and unmatured
     claims shall be valued at the amount that can be reasonably expected to
     be actual and matured.

             "Subsidiary" shall mean (i) any corporation, at least 50% of
     the total combined voting power of all classes of Voting Stock of which
     shall, at the time as of which any determination is being made, be
     owned by the Guarantor, either directly or through Subsidiaries, and
     (ii) any partnership, joint venture or similar entity if at least a 50%
     interest in the profits or capital thereof is owned by the Guarantor,
     either directly or through Subsidiaries (unless such entity can and
     does ordinarily take major business actions without the prior approval,
     direct or indirect, of the Guarantor).



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<PAGE>

             "Surviving Entity" shall have the meaning specified in Section
9(b)(i) of this Guaranty Agreement.

             "Trust Certificates" shall mean the "Certificates" as such
term is defined in the Declaration of Trust.

             "Voting Stock" shall mean, with respect to any corporation,
any shares of stock of such corporation whose holders are entitled
under ordinary circumstances to vote for the election of directors of
such corporation (irrespective of whether at the time stock of any
other class or classes shall have or might have voting power by reason
of the happening of any contingency).




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<PAGE>


         IN WITNESS WHEREOF, the Guarantor has caused this Additional Guaranty
Agreement to be duly executed and delivered as of the date and year first above
written.

                                       TXU ENERGY COMPANY LLC


                                   By:      /s/Kirk R. Oliver
                                      ----------------------------------------
                                   Title: Treasurer and Assistant Secretary


                                   By:      /s/Anthony Horton
                                      -----------------------------------------
                                   Title: Assistant Treasurer


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