SENIOR UNSECURED INTERIM LOAN AGREEMENT

Exhibit 10(xx)

EXECUTION COPY

$4,500,000,000

SENIOR UNSECURED INTERIM LOAN AGREEMENT

Dated as of October 10, 2007

among

TXU CORP.,

as the Borrower,

The Several Lenders

from Time to Time Parties Hereto,

MORGAN STANLEY SENIOR FUNDING, INC.,

as Administrative Agent

and

GOLDMAN SACHS CREDIT PARTNERS L.P.

as Syndication Agent

CITIBANK, N.A.,

CREDIT SUISSE SECURITIES (USA) LLC,

JPMORGAN CHASE BANK, N.A.,

and

LEHMAN COMMERCIAL PAPER INC.

as Co-Documentation Agents

MORGAN STANLEY SENIOR FUNDING, INC.,

GOLDMAN SACHS CREDIT PARTNERS L.P.,

CITIGROUP GLOBAL MARKETS INC.,

CREDIT SUISSE SECURITIES (USA) LLC,

J.P. MORGAN SECURITIES INC.

and LEHMAN BROTHERS INC.

as Joint Lead Arrangers and Bookrunners

TABLE OF CONTENTS

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SCHEDULES

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SENIOR UNSECURED INTERIM LOAN AGREEMENT, dated as of October 10, 2007, among TXU CORP., a Texas corporation (the “ Borrower ”), the lending institutions from time to time parties hereto (each a “ Lender ” and, collectively, the “ Lenders ”), MORGAN STANLEY SENIOR FUNDING, INC., as Administrative Agent (such terms and each other capitalized term used but not defined in this preamble having the meaning provided in Section 1.1 ), GOLDMAN SACHS CREDIT PARTNERS L.P., as Syndication Agent, MORGAN STANLEY SENIOR FUNDING, INC., GOLDMAN SACHS CREDIT PARTNERS L.P., CITIGROUP GLOBAL MARKETS INC., CREDIT SUISSE SECURITIES (USA) LLC, J.P. MORGAN SECURITIES INC. and LEHMAN BROTHERS INC., as Joint Lead Arrangers and Bookrunners, and CITIBANK, N.A., CREDIT SUISSE SECURITIES (USA) LLC, JPMORGAN CHASE BANK, N.A. and LEHMAN COMMERCIAL PAPER INC., as Co-Documentation Agents.

RECITALS:

WHEREAS, pursuant to the Agreement and Plan of Merger (the “ Acquisition Agreement ”), dated as of February 25, 2007, by and among the Borrower, Holdings and Merger Sub, Merger Sub will merge with and into the Borrower (the “ Merger ”), with the Borrower surviving the Merger as a wholly-owned Subsidiary of Holdings;

WHEREAS, to fund, in part, the Merger Funds, it is intended that the Sponsors and certain other investors (collectively, the “ Initial Investors ”) will directly or indirectly make cash equity contributions (the “ Equity Contribution ”) to Holdings and/or a direct or indirect parent thereof in exchange for Stock (which cash will be contributed to Merger Sub) in an aggregate amount equal to, when combined with the fair market value of the Stock of management and existing shareholders of the Borrower rolled over or invested in connection with the Transactions, at least 15% (the “ Minimum Equity Amount ”) of the total sources (including the Existing Notes and the Existing Oncor Notes, but excluding any transition bonds) required to consummate the Merger (the “ Merger Consideration ”), to redeem, refinance or repay certain existing indebtedness or repurchase receivables of the Borrower and its Subsidiaries, including the Repaid Indebtedness (the “ Refinancing ”), and to pay fees, premiums and expenses incurred in connection with the Transactions (such fees, premiums and expenses, together with the Merger Consideration and the Refinancing payment, the “ Merger Funds ”);

WHEREAS, in connection with the foregoing, the Borrower has requested that the Lenders extend credit to the Borrower in the form of Senior Interim Loans on the Closing Date, in an aggregate principal amount of $4,500,000,000, which shall initially consist of (a) $2,000,000,000 of Senior Interim Cash Pay Loans and (b) $2,500,000,000 of Senior Interim Toggle Loans;

WHEREAS, in order to fund, in part, the Merger Funds (a) TCEH will enter into a senior secured credit agreement, dated as of the Closing Date, by and among TCEH, US Holdings, the lenders from time to time party thereto, Citibank, N.A., as administrative agent, collateral agent, swingline lender, revolving letter of credit issuer and deposit letter of credit issuer, Goldman Sachs Credit Partners L.P., as posting agent, posting syndication agent and posting documentation agent, J. Aron & Company, as posting calculation agent, JPMorgan Chase Bank, N.A., as syndication agent and revolving letter of credit issuer, Credit Suisse

Securities (USA) LLC, JPMorgan Chase Bank, N.A., Goldman Sachs Credit Partners L.P., Lehman Commercial Paper Inc. and Morgan Stanley Senior Funding, Inc., as co-documentation agents, JPMorgan Chase Bank, N.A., Citigroup Global Markets Inc., J.P. Morgan Securities Inc., Goldman Sachs Credit Partners L.P., Lehman Brothers Inc., Morgan Stanley Senior Funding, Inc. and Credit Suisse Securities (USA) LLC, as joint lead arrangers and bookrunners and Goldman Sachs Credit Partners L.P., as Posting Lead Arranger and Bookrunner (the “ Senior Secured Credit Agreement ”), pursuant to which TCEH (i) will borrow term loans in an aggregate principal amount of $16,450,000,000 on the Closing Date (the “ Senior Secured Initial Term Loans ”), (ii) may borrow term loans in an aggregate principal amount of up to $4,100,000,000 at any time and from time to time prior to the Delayed Draw Term Loan Commitment Termination Date (as defined in the Senior Secured Credit Agreement) (the “ Senior Secured Delayed Draw Term Loans ”), (iii) will borrow $1,250,000,000 in aggregate principal amount of deposit letter of credit loans on the Closing Date (the “ Senior Secured Deposit L/C Loans ”), (iv) may borrow revolving credit loans (the “ Senior Secured Revolving Credit Loans ”) in aggregate principal amount of up to $2,700,000,000 at any time and from time to time prior to the Revolving Credit Termination Date (as defined in the Senior Secured Credit Agreement); and (v) will borrow under a senior revolving credit facility, the principal amount of which is capped by the MTM Exposures (as defined in the Senior Secured Credit Agreement) (the “ Posting Facility ”); and (b) TCEH will enter into a senior unsecured interim loan agreement, dated as of the Closing Date, by and among TCEH, TCEH Finance Inc., US Holdings, the lenders from time to time party thereto, Morgan Stanley Senior Funding, Inc., as administrative agent, Goldman Sachs Credit Partners L.P., as syndication agent, Citibank, N.A., Credit Suisse Securities (USA) LLC, JPMorgan Chase Bank, N.A., and Lehman Commercial Paper Inc., as co-documentation agents, and Goldman Sachs Credit Partners L.P., Morgan Stanley Senior Funding Inc., Citigroup Global Markets Inc., Credit Suisse Securities (USA) LLC, J.P. Morgan Securities Inc., and Lehman Brothers Inc., as joint lead arrangers and bookrunners (the “ TCEH Senior Unsecured Interim Loan Agreement ”), pursuant to which TCEH will borrow senior unsecured interim loans in an aggregate principal amount of $6,750,000,000, which shall initially consist of (a) $5,000,000,000 of senior interim cash pay loans (the “ TCEH Senior Interim Cash Pay Loans ”) and (b) $1,750,000,000 of senior interim toggle loans (the “ TCEH Senior Interim Toggle Loans ” and, together with the TCEH Senior Interim Cash Pay Loans, the “ TCEH Senior Interim Loans ”);

WHEREAS, the net proceeds of the Senior Interim Loans will be used by the Borrower for the Merger Funds and contributed by the Borrower to TCEH and used by TCEH, together with (a) the net proceeds of the Senior Secured Initial Term Loans, less $400,000,000, (b) the net proceeds of up to $250,000,000 of Senior Secured Revolving Credit Loans, (c) the net proceeds of the Equity Contribution, (d) the net proceeds of the TCEH Senior Interim Loans and (e) cash on hand at TCEH, on the Closing Date (or, in the case of the Refinancing, such later date as may be necessary to effect certain of the Refinancings in accordance with the tender offers therefor). Up to $400,000,000 of proceeds of the Senior Secured Initial Term Loans will be used by TCEH for general corporate purposes. The proceeds of the Posting Facility will be used by TCEH (a) to fund margin payments on over-the-counter natural gas fixed for floating swap transactions between TCEH and certain of its Subsidiaries, on the one hand, and various counterparties, on the other, (b) to fund margin payments on NYMEX futures and swap positions maintained by TCEH and certain of its Subsidiaries and (c) for other general corporate purposes of TCEH and certain of its Subsidiaries (provided that such funds will be applied first to fund margin on Dealer Swaps (as defined in the Senior Secured Credit Agreement) to the extent such transactions are outstanding and any margin is due thereon and second for any other purpose; and

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WHEREAS, the Lenders are willing to make available to the Borrower the Senior Interim Loans upon the terms and subject to the conditions provided herein;

AGREEMENT:

NOW, THEREFORE, in consideration of the premises and the covenants and agreements contained herein, the parties hereto hereby agree as follows:

SECTION 1. Definitions

1.1. Defined Terms .

(a) As used herein, the following terms shall have the meanings specified in this Section 1.1 unless the context otherwise requires:

“ ABR ” shall mean for any day a fluctuating rate per annum equal to the higher of (a) the Federal Funds Effective Rate plus 1/2 of 1% and (b) the rate of interest published by the Wall Street Journal, from time to time, as the prime or base commercial lending rate. If the Administrative Agent is unable to ascertain the Federal Funds Effective Rate due to its inability to obtain sufficient quotations in accordance with the definition thereof, after notice is provided to the Borrower, the ABR shall be determined without regard to clause (a)  above until the circumstances giving rise to such inability no longer exist. Any change in the ABR due to a change in such rate published in the Wall Street Journal or in the Federal Funds Effective Rate shall take effect at the opening of business on the day specified in the public announcement of such change.

“ ABR Loan ” shall mean each Loan bearing interest based on ABR.

“ Acquired Indebtedness ” shall mean, with respect to any specified Person,

(1) Indebtedness of any other Person existing at the time such other Person is merged with or into or became a Restricted Subsidiary of such specified Person, including Indebtedness incurred in connection with, or in contemplation of, such other Person merging with or into or becoming a Restricted Subsidiary of such specified Person, and

(2) Indebtedness secured by a Lien encumbering any asset acquired by such specified Person.

“ Acquisition Agreement ” shall have the meaning provided in the recitals to this Agreement.

“ Administrative Agent ” shall mean Morgan Stanley Senior Funding, Inc., as the administrative agent for the Lenders under this Agreement and the other Loan Documents, or any successor administrative agent pursuant to Section 13 .

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“ Administrative Agent’s Office ” shall mean the Administrative Agent’s address and, as appropriate, account as provided in Schedule 13.2 , or such other address or account as the Administrative Agent may from time to time notify to the Borrower and the Lenders.

“ Administrative Questionnaire ” shall have the meaning provided in Section 13.6(b) .

“ Affiliate ” of any specified Person shall mean any other Person directly or indirectly controlling or controlled by or under direct or indirect common control with such specified Person. For purposes of this definition, “control” (including, with correlative meanings, the terms “controlling,” “controlled by” and “under common control with”), as used with respect to any Person, shall mean the possession, directly or indirectly, of the power to direct or cause the direction of the management or policies of such Person, whether through the ownership of voting securities, by agreement or otherwise.

“ Agent Parties ” shall have the meaning provided in Section 13.17(d).

“ Agents ” shall mean the Administrative Agent, the Syndication Agent, each Co-Documentation Agent, each Joint Lead Arranger and each Joint Bookrunner.

“ Agreement ” shall mean this Senior Unsecured Interim Loan Agreement.

“ Applicable ABR Margin ” shall mean at any date, with respect to each ABR Loan, (a) 3.00% per annum with respect to Senior Cash Pay Loans and (b) 3.25% per annum with respect to Senior Toggle Loans. If the Loans are not paid within the six-month period following the Closing Date, the Applicable ABR Margin will increase by 0.50%  per annum at the end of such six-month period and shall increase by an additional 0.25%  per annum at the end of each three-month period thereafter until the Interim Loan Conversion Date. At the Interim Loan Conversion Date the Applicable ABR Margin will increase by 0.25%  per annum and shall increase by an additional 0.25%  per annum at the end of each three month period thereafter until the Term Loan Maturity Date. Notwithstanding the foregoing, the Applicable ABR Margin shall be capped such that the applicable interest rate (exclusive of interest at the Default Rate) (i) in the case of Senior Cash Pay Loans, shall not exceed the Senior Cash Pay Fixed Rate and (ii) in the case of Senior Toggle Loans, excluding the effect of the PIK Margin, shall not exceed the Senior Toggle Fixed Rate.

“ Applicable Laws ” shall mean, as to any Person, any law (including common law), statute, regulation, ordinance, rule, order, decree, judgment, consent decree, writ, injunction, settlement agreement or governmental requirement enacted, promulgated or imposed or entered into or agreed by any Government Authority (including the PUCT and ERCOT), in each case applicable to or binding on such Person or any of its property or assets or to which such Person or any of its property or assets is subject. Applicable Laws shall also include commitments, undertakings, and stipulations (relating to Oncor and its Subsidiaries set forth in the Joint Report and Application of Oncor Electric Delivery Company and Texas Energy Future Holdings Limited Partnership pursuant to Public Utility Regulatory Act 14.101 before the PUCT, to the extent such commitments, undertakings and stipulations are embodied in a final order issued by PUCT and (b) relating to the Loan Parties and their Affiliates other than Oncor and its Subsidiaries as set forth on Schedule 1,1(g) hereto.

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“ Applicable LIBOR Margin ” shall mean at any date, with respect to each LIBOR Loan, (a) 4.00% per annum with respect to Senior Cash Pay Loans and (b) 4.25% per annum with respect to Senior Toggle Loans. If the Loans are not paid within the six-month period following the Closing Date, the Applicable LIBOR Margin will increase by 0.50%  per annum at the end of such six-month period and shall increase by an additional 0.25%  per annum at the end of each three-month period thereafter until the Interim Loan Conversion Date. At the Interim Loan Conversion Date the Applicable LIBOR Margin will increase by 0.25%  per annum and shall increase by an additional 0.25%  per annum at the end of each three month period thereafter until the Term Loan Maturity Date. Notwithstanding the foregoing, the Applicable LIBOR Margin shall be capped such that the applicable interest rate (exclusive of interest at the Default Rate) (i) in the case of Senior Cash Pay Loans, shall not exceed the Senior Cash Pay Fixed Rate and (ii) in the case of Senior Toggle Loans, excluding the effect of the PIK Margin, shall not exceed the Senior Toggle Fixed Rate.

“ Approved Fund ” shall mean any Fund that is administered or managed by (a) a Lender, (b) an Affiliate of a Lender or (c) an entity or an Affiliate of an entity that administers or manages a Lender.

“ Asset Sale ” shall mean:

(1) the sale, conveyance, transfer or other disposition, whether in a single transaction or a series of related transactions, of property or assets (including by way of a Sale and Lease-Back Transaction) of the Borrower or any of its Restricted Subsidiaries (each referred to in this definition as a “disposition”); or

(2) the issuance or sale of Equity Interests of any Restricted Subsidiary, whether in a single transaction or a series of related transactions (other than Preferred Stock of Restricted Subsidiaries issued in compliance with Section 9.7 );

in each case, other than:

(a) any disposition of Cash Equivalents or Investment Grade Securities or obsolete or worn out equipment (including any such equipment that has been refurbished in contemplation of such disposition) in the ordinary course of business or any disposition of inventory or goods (or other assets) held for sale in the ordinary course of business;

(b) the disposition of all or substantially all of the assets of the Borrower in a manner permitted pursuant to the provisions of Section 9.14 or any disposition that constitutes a Change of Control pursuant to this Agreement;

(c) the making of any Restricted Payment or Permitted Investment that is permitted to be made, and is made, under Section 9.5 ;

(d) any disposition of assets or issuance or sale of Equity Interests of any Restricted Subsidiary in any transaction or series of related transactions with an aggregate fair market value of less than (x) prior to the Interim Loan Conversion Date, $50,000,000 and (y) thereafter, $75,000,000;

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(e) any disposition of property or assets or issuance of securities by a Restricted Subsidiary of the Borrower to the Borrower or by the Borrower or a Restricted Subsidiary of the Borrower to another Restricted Subsidiary of the Borrower;

(f) to the extent allowable under Section 1031 of the Code or any comparable or successor provision, any exchange of like property (excluding any boot thereon) for use in a Similar Business;

(g) the lease, assignment or sublease of any real or personal property in the ordinary course of business;

(h) (i) any issuance or sale of Equity Interests in, or Indebtedness or other securities of, an Unrestricted Subsidiary (other than an Oncor Subsidiary) and (ii) up to (x) prior to the Interim Loan Conversion Date, $400,000,000 and (y) thereafter, $1,250,000,000 of aggregate Net Asset Sale Proceeds from the sale of Equity Interests in, or Indebtedness or other securities of any of the Oncor Subsidiaries; provided that such $400,000,000 (prior to the Interim Loan Conversion Date) or $1,250,000,000 (thereafter) of Net Asset Sale Proceeds are used to reduce intercompany loans from TCEH outstanding at the time such Net Asset Sale Proceeds are received and required to be repaid therefrom;

(i) foreclosures on assets;

(j) sales of accounts receivable, or participations therein, in connection with any Receivables Facility for the benefit of the Borrower or any of its Restricted Subsidiaries;

(k) any financing transaction with respect to property built or acquired by the Borrower or any Restricted Subsidiary after the Closing Date, including Sale and Lease-Back Transactions and asset securitizations permitted by this Agreement;

(l) [ Reserved ] ;

(m) sales, transfers and other dispositions (i) of Investments in joint ventures to the extent required by, or made pursuant to, customary buy/sell or put/call arrangements between the joint venture parties set forth in joint venture arrangements and similar binding arrangements or (ii) to joint ventures in connection with the dissolution or termination of a joint venture to the extent required pursuant to joint venture and similar arrangements;

(n) [ Reserved ] ;

(o) [ Reserved ] ;

(p) [ Reserved ] ;

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(q) any Casualty Event provided the net proceeds therefrom are deemed to be Net Asset Sale Proceeds and are applied in accordance with Section 9.8(b) or the Borrower or such Restricted Subsidiary delivers to the Administrative Agent a Restoration Certificate with respect to plans to invest (and reinvests within 450 days from the date of receipt of the Net Asset Sale Proceeds) and;

(r) the execution of (or amendment to), settlement of or unwinding of any Hedging Obligation in the ordinary course of business;

(s) any disposition of mineral rights (other than coal and lignite mineral rights); provided the net proceeds therefrom are deemed to be Net Asset Sale Proceeds and are applied in accordance with Section 9.8(b) ;

(t) any sale, transfer or other disposal of any real property that is (i) primarily used or intended to be used for mining which has either been reclaimed, or has not been used for mining in a manner which requires reclamation, and in either case has been determined by TCEH not to be necessary for use for mining, (ii) used as buffer land, but no longer serves such purpose or its use is restricted such that it will continue to be buffer land, or (iii) was acquired in connection with power generation facilities, but has been determined by TCEH to no longer be commercially suitable for such purpose;

(u) [ Reserved ] ;

(v) dispositions of power, capacity, heat rate, renewable energy credits, waste by-products, energy, electricity, coal and lignite, oil and other petroleum based liquids, emissions and other environmental credits, ancillary services, fuel (including all forms of nuclear fuel and natural gas) and other related assets or products of services, including assets related to trading activities or the sale of inventory or contracts related to any of the foregoing, in each case in the ordinary course of business;

(w) [ Reserved ] ;

(x) any disposition of assets in connection with salvage activities, provided the net proceeds therefrom are deemed to be Net Asset Sale Proceeds and are applied in accordance with Section 9.8(b) ; and

(y) any sale, transfer or other disposition of any assets required by any Government Authority; provided the net proceeds therefrom are deemed to be Net Asset Sale Proceeds and applied in accordance with Section 9.8(b) .

“ Asset Sale Offer ” shall have the meaning provided in Section 9.8(c) .

“ Assignment and Acceptance ” shall mean an assignment and acceptance substantially in the form of Exhibit H , or such other form as may be approved by the Administrative Agent.

“ Authorized Officer ” shall mean the President, the Chief Executive Officer, the Chief Financial Officer, the Chief Operating Officer, the Treasurer, the Assistant Treasurer, with respect to certain limited liability companies or partnerships that do not have officers, any manager, managing member or general partner thereof, any other senior officer of the Borrower

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or any other Loan Party designated as such in writing to the Administrative Agent by the Borrower or any other Loan Party, as applicable, and, with respect to any document (other than the solvency certificate) delivered on the Closing Date, the Secretary or the Assistant Secretary of any Loan Party. Any document delivered hereunder that is signed by an Authorized Officer shall be conclusively presumed to have been authorized by all necessary corporate, limited liability company, partnership and/or other action on the part of the Borrower or any other Loan Party and such Authorized Officer shall be conclusively presumed to have acted on behalf of such Person.

“ Bankruptcy Code ” shall mean Title 11 of the United States Code, as amended.

“ Bankruptcy Law ” shall mean the Bankruptcy Code and any similar federal, state or foreign law for the relief of debtors.

“ benefited Lender ” shall have the meaning provided in Section 13.8(a) .

“ Board ” shall mean the Board of Governors of the Federal Reserve System of the United States (or any successor).

“ Borrower ” shall have the meaning provided in the preamble to this Agreement.

“ Borrowing ” shall mean and include the incurrence of the Loans on the Closing Date (or resulting from conversions on a given date after the Closing Date) having, in the case of LIBOR Loans, the same Interest Period ( provided that ABR Loans incurred pursuant to Section 2.10(b) shall be considered part of any related Borrowing of LIBOR Loans).

“ Business Day ” shall mean any day excluding Saturday, Sunday and any other day on which banking institutions in New York City are authorized by law or other governmental actions to close, and, if such day relates to (a) any interest rate settings as to a LIBOR Loan, (b) any fundings, disbursements, settlements and payments in respect of any such LIBOR Loan, or (c) any other dealings pursuant to this Agreement in respect of any such LIBOR Loan, such day shall be a day on which dealings in deposits in Dollars are conducted by and between banks in the London interbank eurodollar market.

“ Capital Stock ” shall mean:

(1) in the case of a corporation, corporate stock;

(2) in the case of an association or business entity, any and all shares, interests, participations, rights or other equivalents (however designated) of corporate stock;

(3) in the case of a partnership or limited liability company, partnership or membership interests (whether general or limited); and

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(4) any other interest or participation that confers on a Person the right to receive a share of the profits and losses of, or distributions of assets of, the issuing Person.

“ Capitalized Lease Obligation ” shall mean, at the time any determination thereof is to be made, the amount of the liability in respect of a capital lease that would at such time be required to be capitalized and reflected as a liability on a balance sheet (excluding the footnotes thereto) in accordance with GAAP; provided that any obligations existing on the Closing Date (i) that were not included on the balance sheet of the Borrower as capital lease obligations and (ii) that are subsequently recharacterized as capital lease obligations due to a change in accounting treatment shall for all purposes not be treated as Capitalized Lease Obligations.

“ Capitalized Software Expenditures ” shall mean, for any period, the aggregate of all expenditures (whether paid in cash or accrued as liabilities) by a Person and its Restricted Subsidiaries during such period in respect of purchased software or internally developed software and software enhancements that, in conformity with GAAP, are or are required to be reflected as capitalized costs on the consolidated balance sheet of a Person and its Restricted Subsidiaries.

“ Cash Equivalents ” shall mean:

(1) Dollars;

(2) euros or any national currency of any participating member state of the EMU or such local currencies held by the Borrower and its Restricted Subsidiaries from time to time in the ordinary course of business;

(3) securities issued or directly and fully and unconditionally guaranteed or insured by the U.S. government (or any agency or instrumentality thereof the securities of which are unconditionally guaranteed as a full faith and credit obligation of the U.S. government) with maturities, unless such securities are deposited to defease Indebtedness, of 24 months or less from the date of acquisition;

(4) certificates of deposit, time deposits and eurodollar time deposits with maturities of one year or less from the date of acquisition, bankers’ acceptances with maturities not exceeding one year and overnight bank deposits, in each case with any commercial bank having capital and surplus of not less than $500,000,000 in the case of U.S. banks and $100,000,000 (or the Dollar equivalent as of the date of determination) in the case of non-U.S. banks;

(5) repurchase obligations for underlying securities of the types described in clauses (3) and (4) entered into with any financial institution meeting the qualifications specified in clause (4) above;

(6) commercial paper rated at least P-1 by Moody’s or at least A-1 by S&P and in each case maturing within 24 months after the date of creation thereof;

(7) marketable short-term money market and similar securities having a rating of at least P-2 or A-2 from either Moody’s or S&P, respectively (or, if at any time neither Moody’s nor S&P shall be rating such obligations, an equivalent rating from another Rating Agency) and in each case maturing within 24 months after the date of creation thereof;

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(8) investment funds investing 95% of their assets in securities of the types described in clauses (1) through (7) above;

(9) readily marketable direct obligations issued by any state, commonwealth or territory of the United States or any political subdivision or taxing authority thereof having an Investment Grade Rating from either Moody’s or S&P with maturities of 24 months or less from the date of acquisition;

(10) Indebtedness or Preferred Stock issued by Persons with a rating of A or higher from S&P or A2 or higher from Moody’s with maturities of 24 months or less from the date of acquisition; and

(11) Investments with average maturities of 24 months or less from the date of acquisition in money market funds rated AAA- (or the equivalent thereof) or better by S&P or Aaa3 (or the equivalent thereof) or better by Moody’s.

Notwithstanding the foregoing, Cash Equivalents shall include amounts denominated in currencies other than those provided in clauses (1) and (2) above; provided that such amounts are converted into any currency listed in clauses (1) and (2) as promptly as practicable and in any event within ten Business Days following the receipt of such amounts.

“ Cash Interest ” shall have the meaning provided in Section 2.8(a)(ii) .

“ Casualty Event ” shall mean any taking under power of eminent domain or similar proceeding and any insured loss; provided that any such taking or similar proceeding or insured loss that results in Net Asset Sale Proceeds of less than (x) prior to the Interim Loan Conversion Date, $50,000,000 and (y) thereafter, $75,000,000 shall not be deemed a Casualty Event.

“ Change in Law ” shall mean (a) the adoption of any Applicable Laws after the date of this Agreement, (b) any change in any Applicable Laws or in the interpretation or application thereof by any Government Authority after the date of this Agreement or (c) compliance by any party with any guideline, request, directive or order issued or made after the date hereof by any central bank or other government or quasi-governmental authority (whether or not having the force of law).

“ Change of Control ” shall mean the occurrence of any of the following:

(1) the sale, lease or transfer, in one or a series of related transactions, of all or substantially all of the assets of the Borrower and its Subsidiaries, taken as a whole, to any Person other than a Permitted Holder; or

(2) the Borrower becomes aware (by way of a report or any other filing pursuant to Section 13(d) of the Exchange Act, proxy, vote, written notice or otherwise) of the acquisition by any Person or group (within the meaning of Section 13(d)(3) or Section 14(d)(2) of the Exchange Act or any successor provision), including any group acting for the purpose of acquiring, holding or disposing of securities (within the meaning of Rule 13d-5(b)(1) under the Exchange Act or any successor provision), other than the Permitted Holders, in a single

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transaction or in a related series of transactions, by way of merger, consolidation or other business combination or purchase of beneficial ownership (within the meaning of Rule 13d-3 under the Exchange Act, or any successor provision) of 50% or more of the total voting power of the Voting Stock of the Borrower or any of its direct or indirect parent companies.

“ Change of Control Offer ” shall have the meaning provided in Section 9.12(a).

“ Change of Control Prepayment ” shall have the meaning provided in Section 9.12(a).

“ Change of Control Prepayment Date ” shall have the meaning set provided in Section 9.12(a)(2).

“ Class ”, when used in reference to any Loan or Borrowing, shall refer to whether such Loan, or the Loans comprising such Borrowing, are Senior Cash Pay Loans or Senior Toggle Loans and, when used in reference to any Commitment, refers to whether such Commitment is a Senior Interim Cash Pay Loan Commitment or a Senior Interim Toggle Loan Commitment.

“ Closing Date ” shall mean the date of the initial Borrowings hereunder.

“ Code ” shall mean the Internal Revenue Code of 1986, as amended from time to time. Section references to the Code are to the Code as in effect at the date of this Agreement, and any subsequent provisions of the Code, amendatory thereof, supplemental thereto or substituted therefor.

“ Co-Documentation Agents ” shall mean Citibank N.A., Credit Suisse Securities (USA) LLC, JPMorgan Chase Bank, N.A. and Lehman Commercial Paper Inc.

“ Collateral Posting Facility ” shall mean any senior cash posting credit facility, the size of which is capped by the mark-to-market loss, inclusive of any unpaid settlement amounts, of TCEH and its Subsidiaries on a hypothetical portfolio of commodity swaps, forwards and futures transactions that correspond to or replicate all or a portion of actual transactions by TCEH and its Subsidiaries that are outstanding on, or entered into from time to time on or after, the Closing Date.

“ Commitment Letter ” shall mean the amended and restated commitment letter, dated July 20, 2007, as amended by that certain Letter Agreement dated October 10, 2007, among TCEH (as successor in interest to Merger Sub) and Citigroup Global Markets Inc., Credit Suisse Cayman Islands Branch, Credit Suisse Securities (USA) LLC, Goldman Sachs Credit Partners L.P., JPMorgan Chase Bank, N.A., J.P. Morgan Securities Inc., Lehman Brothers Inc., Lehman Brothers Holdings Inc., Lehman Commercial Paper Inc., Lehman Brothers Commercial Bank and Morgan Stanley Senior Funding, Inc.

“ Commitments ” shall mean, with respect to each Lender (to the extent applicable), such Lender’s Senior Interim Cash Pay Loan Commitment and/or Senior Interim Toggle Loan Commitment, as the context requires.

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“ Committed Lenders ” shall mean Citibank N.A., Credit Suisse Cayman Islands Branch, Goldman Sachs Credit Partners L.P., JPMorgan Chase Bank Inc., N.A., Lehman Loan Funding, LLC and Morgan Stanley Senior Funding, Inc.

“ Communications ” shall have the meaning provided in Section 13.17 .

“ Confidential Information ” shall have the meaning provided in Section 13.16 .

“ Consolidated Depreciation and Amortization Expense ” shall mean with respect to any Person for any period, the total amount of depreciation and amortization expense, including the amortization of deferred financing fees, nuclear fuel costs, depletion of coal or lignite reserves, debt issuance costs, commissions, fees and expenses and Capitalized Software Expenditures, of such Person and its Restricted Subsidiaries for such period on a consolidated basis and otherwise determined in accordance with GAAP.

“ Consolidated Interest Expense ” shall mean, with respect to any Person for any period, without duplication, the sum of:

(1) consolidated interest expense of such Person and its Restricted Subsidiaries for such period, to the extent such expense was deducted (and not added back) in computing Consolidated Net Income (including (a) amortization of original issue discount resulting from the issuance of Indebtedness at less than par, (b) all commissions, discounts and other fees and charges owed with respect to letters of credit or bankers’ acceptances or any Collateral Posting Facility or similar facilities, (c) non-cash interest payments (but excluding any non-cash interest expense attributable to the movement in the mark to market valuation of Hedging Obligations or other derivative instruments pursuant to GAAP), (d) the interest component of Capitalized Lease Obligations, and (e) net payments, if any, pursuant to interest rate Hedging Obligations with respect to Indebtedness, and excluding, (u) accretion of asset retirement obligations and accretion or accrual of discounted liabilities not constituting Indebtedness, (v) any expense resulting from the discounting of the Existing Notes or other Indebtedness in connection with the application of purchase accounting, (w) “additional interest” with respect to the Senior Refinancing Registration Rights Agreement and any comparable “additional interest” with respect to other securities, (x) amortization of reacquired Indebtedness, deferred financing fees, debt issuance costs, commissions, fees and expenses, (y) any expensing of bridge, commitment and other financing fees and (z) commissions, discounts, yield and other fees and charges (including any interest expense) related to any Receivables Facility); plus

(2) consolidated capitalized interest of such Person and its Restricted Subsidiaries for such period, whether paid or accrued; less

(3) interest income of such Person and its Restricted Subsidiaries for such period.

For purposes of this definition, interest on a Capitalized Lease Obligation shall be deemed to accrue at an interest rate reasonably determined by such Person to be the rate of interest implicit in such Capitalized Lease Obligation in accordance with GAAP.

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“ Consolidated Leverage Ratio ” as of any date of determination, shall mean the ratio of (x) Consolidated Total Indebtedness of the Borrower computed as of the end of the most recent fiscal quarter for which internal financial statements are available immediately preceding the date on which such event for which such calculation is being made shall occur to (y) the aggregate amount of EBITDA of the Borrower for the period of the most recently ended four full consecutive fiscal quarters for which internal financial statements are available immediately preceding the date on which such event for which such calculation is being made shall occur, in each case with such pro forma adjustments to Consolidated Total Indebtedness and EBITDA as are appropriate and consistent with the pro forma adjustment provisions provided in the definition of “Fixed Charge Coverage Ratio.”

“ Consolidated Net Income ” shall mean, with respect to any Person for any period, the aggregate of the Net Income of such Person for such period, on a consolidated basis, and otherwise determined in accordance with GAAP; provided , however , that, without duplication,

(1) any after-tax effect of extraordinary, non-recurring or unusual gains or losses (less all fees and expenses relating thereto) or expenses (including Transaction fees and expenses to the extent incurred on or prior to December 31, 2008), severance, relocation costs, consolidation and closing costs, integration and facilities opening costs, business optimization costs, transition costs, restructuring costs, signing, retention or completion bonuses, and curtailments or modifications to pension and post-retirement employee benefit plans shall be excluded;

(2) the cumulative effect of a change in accounting principles during such period shall be excluded;

(3) any after-tax effect of income (loss) from disposed, abandoned or discontinued operations and any net after-tax gains or losses on disposal of disposed, abandoned, transferred, closed or discontinued operations shall be excluded;

(4) any after-tax effect of gains or losses (less all fees and expenses relating thereto) attributable to asset dispositions or abandonments other than in the ordinary course of business, as determined in good faith by the Borrower, shall be excluded;

(5) the Net Income for such period of any Person that (a) is not a Subsidiary, (b) is an Unrestricted Subsidiary or (c) is accounted for by the equity method of accounting, shall be excluded; provided that Consolidated Net Income of the Borrower shall be increased by the amount of dividends or distributions or other payments that are actually paid in cash (or to the extent converted into cash) to the referent Person or a Restricted Subsidiary thereof in respect of such period;

(6) solely for the purpose of determining the amount available for Restricted Payments under clause (3)(a) of Section 9.5(a) hereof, the Net Income for such period of any Restricted Subsidiary (other than any Guarantor) shall be excluded to the extent that the declaration or payment of dividends or similar distributions by that Restricted Subsidiary of its Net Income is not at the date of determination wholly permitted without any prior governmental

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approval (which has not been obtained) or, directly or indirectly, by the operation of the terms of its charter or any agreement, instrument, judgment, decree, order, statute, rule, or governmental regulation applicable to that Restricted Subsidiary or its stockholders, unless such restriction with respect to the payment of dividends or similar distributions has been legally waived or is otherwise permitted under Section 9.6 hereof; provided that Consolidated Net Income of the Borrower will be increased by the amount of dividends or other distributions or other payments actually paid in cash (or to the extent converted into cash) or Cash Equivalents to the Borrower or a Restricted Subsidiary thereof in respect of such period, to the extent not already included therein;

(7) effects of all adjustments (including the effects of such adjustments pushed down to the Borrower and its Restricted Subsidiaries) in such Person’s consolidated financial statements pursuant to GAAP resulting from the application of purchase accounting in relation to the Transactions or any consummated acquisition or the amortization or write-off of any amounts thereof, net of taxes, shall be excluded;

(8) any net after-tax effect of income (loss) attributable to the early extinguishment of Indebtedness (other than Hedging Obligations) shall be excluded;

(9) any impairment charge or asset write-off, including, without limitation, impairment charges or asset write-offs related to intangible assets, long-lived assets or investments in debt and equity securities, in each case, pursuant to GAAP and the amortization of intangibles arising pursuant to GAAP shall be excluded;

(10) any non-cash compensation expense recorded from grants of stock appreciation or similar rights, stock options, restricted stock or other rights, and any cash charges associated with the rollover, acceleration or payout of Equity Interests by management of the Borrower or any of its direct or indirect parent companies in connection with the Transactions, shall be excluded;

(11) any fees and expenses incurred during such period, or any amortization thereof for such period, in connection with any acquisition, Investment, Asset Sale, issuance or repayment of Indebtedness, issuance of Equity Interests, refinancing transaction or amendment or modification of any debt instrument (in each case, including any such transaction consummated prior to the Closing Date and any such transaction undertaken but not completed) and any charges or non-recurring merger costs incurred during such period as a result of any such transaction shall be excluded;

(12) accruals and reserves that are established or adjusted within twelve months after the Closing Date that are so required to be established as a result of the Transactions in accordance with GAAP, or changes as a result of adoption or modification of accounting policies, shall be excluded;

(13) to the extent covered by insurance and actually reimbursed, or, so long as the Borrower has made a determination that there exists reasonable evidence that such amount will in fact be reimbursed by the insurer and only to the extent that such amount is (a) not denied by the applicable carrier in writing within 180 days and (b) in fact reimbursed within 365 days of the date of such evidence (with a deduction for any amount so added back to the extent not so reimbursed within 365 days), expenses with respect to liability or casualty events or business interruption shall be excluded;

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(14) any net after-tax effect of unrealized income (loss) attributable to Hedging Obligations or other derivative instruments shall be excluded; and

(15) any benefit from any fair market value of any contract as recorded on the balance sheet at the time of the Transactions shall be excluded.

Notwithstanding the foregoing, for the purpose of Section 9.5(a) hereof only (other than clause (3)(d)  thereof), there shall be excluded from Consolidated Net Income any income arising from any sale or other disposition of Restricted Investments made by the Borrower and its Restricted Subsidiaries, any repurchases and redemptions of Restricted Investments from the Borrower and its Restricted Subsidiaries, any repayments of loans and advances which constitute Restricted Investments by the Borrower or any of its Restricted Subsidiaries, any sale of the stock of an Unrestricted Subsidiary or any distribution or dividend from an Unrestricted Subsidiary, in each case only to the extent such amounts increase the amount of Restricted Payments permitted under clause (3)(d) of Section 9.5(a) hereof.

“ Consolidated Secured Debt Ratio ” shall mean, as of any date of determination, the ratio of (x) Consolidated Secured Indebtedness computed as of the end of the most recent fiscal quarter for which internal financial statements are available immediately preceding the date on which such event for which such calculation is being made shall occur to (y) the aggregate amount of EBITDA of the Borrower for the period of the most recently ended four full consecutive fiscal quarters for which internal financial statements are available immediately preceding the date on which such event for which such calculation is being made shall occur, in each case with such pro forma adjustments to Consolidated Secured Indebtedness and EBITDA as are appropriate and consistent with the pro forma adjustment provisions provided in the definition of “Fixed Charge Coverage Ratio”.

“ Consolidated Secured Indebtedness ” shall mean Consolidated Total Indebtedness secured by a Lien on any assets of the Borrower or any of its Restricted Subsidiaries.

“ Consolidated Total Assets ” shall mean, as of any date of determination, the amount that would, in conformity with GAAP, be set forth opposite the caption “ total assets ” (or any like caption), after intercompany eliminations, on a consolidated balance sheet of the Borrower and the Restricted Subsidiaries at such date.

“ Consolidated Total Indebtedness ” shall mean, as at any date of determination, an amount equal to (1) the aggregate amount of all outstanding Indebtedness of the Borrower and its Restricted Subsidiaries on a consolidated basis consisting of Indebtedness for borrowed money, debt obligations evidenced by promissory notes and similar instruments, letters of credit (only to the extent of any unreimbursed drawings thereunder) and Obligations in respect of Capitalized Lease Obligations, plus (2) the aggregate amount of all outstanding Disqualified Stock of the Borrower and all Disqualified Stock and Preferred Stock of its Restricted

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Subsidiaries on a consolidated basis, with the amount of such Disqualified Stock and Preferred Stock equal to the greater of their respective voluntary or involuntary liquidation preferences and maximum fixed repurchase prices, in each case determined on a consolidated basis in accordance with GAAP, less (3) the aggregate amount of all Unrestricted Cash and less (4) all Deposit L/C Loans and Incremental Deposit L/C Loans outstanding on such date of determination. For purposes hereof, the “ maximum fixed repurchase price ” of any Disqualified Stock or Preferred Stock that does not have a fixed repurchase price shall be calculated in accordance with the terms of such Disqualified Stock or Preferred Stock as if such Disqualified Stock or Preferred Stock were purchased on any date on which Consolidated Total Indebtedness shall be required to be determined, and if such price is based upon, or measured by, the fair market value of such Disqualified Stock or Preferred Stock, such fair market value shall be determined reasonably and in good faith by the Borrower.

“ Contingent Obligations ” shall mean, with respect to any Person, any obligation of such Person guaranteeing any leases, dividends or other obligations that do not constitute Indebtedness (“ primary obligations ”) of any other Person (the “ primary obligor ”) in any manner, whether directly or indirectly, including, without limitation, any obligation of such Person, whether or not contingent,

(1) to purchase any such primary obligation or any property constituting direct or indirect security therefor,

(2) to advance or supply funds,

(a) for the purchase or payment of any such primary obligation, or

(b) to maintain working capital or equity capital of the primary obligor or otherwise to maintain the net worth or solvency of the primary obligor, or

(3) to purchase property, securities or services primarily for the purpose of assuring the owner of any such primary obligation of the ability of the primary obligor to make payment of such primary obligation against loss in respect thereof.

“ Contractual Requirement ” shall have the meaning provided in Section 8.3 .

“ Covered Commodity ” shall mean any energy, electricity generation, capacity, power, heat rate, congestion, natural gas, nuclear fuel (including enrichment and conversion), diesel fuel, fuel oil, other petroleum-based liquids, coal, lignite, weather, emissions and other environmental credits, waste by-products, renewable energy credit, or any other energy related commodity or service (including ancillary services and related risks (such as location basis)).

“ Credit Event ” shall mean and include the making (but not the conversion or continuation) of a Loan, provided that the accrual of PIK Interest shall not constitute a Credit Event.

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“ Credit Facilities ” shall mean, with respect to the Borrower or any of its Restricted Subsidiaries, one or more debt facilities, including the facilities hereunder, the TCEH Senior Secured Facilities or other financing arrangements (including, without limitation, commercial paper facilities or indentures) providing for revolving credit loans, term loans, letters of credit or other long-term indebtedness, including any notes, mortgages, guarantees, collateral documents, instruments and agreements executed in connection therewith, and any amendments, supplements, modifications, extensions, renewals, restatements or refundings thereof and any indentures or credit facilities or commercial paper facilities that replace, refund or refinance any part of the loans, notes, other credit facilities or commitments thereunder, including any such replacement, refunding or refinancing facility or indenture that increases the amount permitted to be borrowed thereunder or alters the maturity thereof ( provided that such increase in borrowings is permitted under Section 9.7 hereof) or adds Restricted Subsidiaries as additional borrowers or guarantors thereunder and whether by the same or any other agent, lender or group of lenders.

“ Debt Incurrence Prepayment Event ” shall mean any issuance or incurrence by the Borrower, US Holdings, Energy Future Holding Company or any other Guarantor, of any Refinancing Indebtedness (excluding any Indebtedness permitted to be issued or incurred under Section 9.7(b) other than Section 9.7(b)(2 ) or 9.7(b)(13))  with respect to any refinancing of Indebtedness incurred under Section 9.7(b)(2 ).

“ Default ” shall mean any event that is, or with the passage of time or the giving of notice or both would be, an Event of Default.

“ Default Rate ” shall have the meaning provided in Section 2.8(d) .

“ Defaulting Lender ” shall mean any Lender with respect to which a Lender Default is in effect.

“ Deposit L/C Loan ” shall mean Deposit L/C Loans under, and as defined in, the TCEH Senior Secured Facilities.

“ Designated Non-Cash Consideration ” shall mean the fair market value of non-cash consideration received by the Borrower or a Restricted Subsidiary in connection with an Asset Sale that is so designated as Designated Non-Cash Consideration pursuant to an Officer’s Certificate, setting forth the basis of such valuation, executed by the principal financial officer of the Borrower, less the amount of cash or Cash Equivalents received in connection with a subsequent sale of or collection on such Designated Non-Cash Consideration.

“ Designated Preferred Stock ” shall mean Preferred Stock of the Borrower or any parent corporation thereof (in each case other than Disqualified Stock) that is issued for cash (other than to a Restricted Subsidiary or an employee stock ownership plan or trust established by the Borrower or any of its Subsidiaries) and is so designated as Designated Preferred Stock, pursuant to an Officer’s Certificate executed by the principal financial officer of the Borrower or the applicable parent corporation thereof, as the case may be, on the issuance date thereof, the cash proceeds of which are excluded from the calculation provided in clause (3) of Section 9.5(a) hereof.

“ Disqualified Stock ” shall mean, with respect to any Person, any Capital Stock of such Person which, by its terms, or by the terms of any security into which it is convertible or for which it is putable or exchangeable, or upon the happening of any event, matures or is mandatorily redeemable (other than solely as a result of a change of control or asset sale)

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pursuant to a sinking fund obligation or otherwise, or is redeemable at the option of the holder thereof (other than solely as a result of a change of control or asset sale), in whole or in part, in each case prior to the date 91 days after the earlier of October 15, 2017 or the date the Loans are no longer outstanding; provided , however, that if such Capital Stock is issued to any plan for the benefit of employees of the Borrower or its Subsidiaries or by any such plan to such employees, such Capital Stock shall not constitute Disqualified Stock solely because it may be required to be repurchased by the Borrower or its Subsidiaries in order to satisfy applicable statutory or regulatory obligations.

“ Dollars ” and “ $ ” shall mean dollars in lawful currency of the United States of America.

“ Domestic Subsidiary ” shall mean each Subsidiary of TCEH that is organized under the laws of the United States, any state thereof or the District of Columbia.

“ EBITDA ” shall mean, with respect to any Person for any period, the Consolidated Net Income of such Person for such period

(1) increased (without duplication) by:

(a) provision for taxes based on income or profits or capital gains, including, without limitation, foreign, federal, state, franchise, excise, value-added and similar taxes and foreign withholding taxes (including penalties and interest related to such taxes or arising from tax examinations) of such Person paid or accrued during such period, deducted (and not added back) in computing Consolidated Net Income; plus

(b) Fixed Charges of such Person for such period (including (x) net losses on Hedging Obligations or other derivative instruments entered into for the purpose of hedging interest rate risk and (y) costs of surety bonds in connection with financing activities, in each case, to the extent included in Fixed Charges), together with items excluded from the definition of “Consolidated Interest Expense” pursuant to clauses (1)(u), (v), (w), (x), (y) and (z) of the definition thereof, and, in each such case, to the extent the same were deducted (and not added back) in calculating such Consolidated Net Income; plus

(c) Consolidated Depreciation and Amortization Expense of such Person for such period to the extent the same was deducted (and not added back) in computing Consolidated Net Income; plus

(d) any fees, expenses or charges (other than depreciation or amortization expense) related to any Equity Offering, Permitted Investment, acquisition, disposition, recapitalization or the incurrence of Indebtedness permitted to be incurred by such Person and its Restricted Subsidiaries, by this Agreement (including a refinancing transaction or amendment or other modification of any debt instrument) (whether or not successful), including (i) such fees, expenses or charges related to this Agreement, the offering of the Senior Notes, the offering of the TCEH Notes, the TCEH Senior Unsecured Interim Loan Agreement, the TCEH Senior Secured Facilities and any Receivables Facility, (ii) any amendment or other modification of the Senior Interim Loans, (iii) any such transaction consummated prior to the Closing Date and any such transaction undertaken but not completed and (iv) any charges or non-recurring merger costs as a result of any such transaction, in each case, deducted (and not added back) in computing Consolidated Net Income; plus

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(e) the amount of any restructuring charge or reserve deducted (and not added back) in such period in computing Consolidated Net Income, including any costs incurred in connection with acquisitions after the Closing Date, costs related to the closure and/or consolidation of facilities; plus

(f) any other non-cash charges, including any write-offs or write-downs, reducing Consolidated Net Income for such period ( provided that if any such non-cash charges represent an accrual or reserve for potential cash items in any future period, the cash payment in respect thereof in such future period shall be subtracted from EBITDA to such extent, and excluding amortization of a prepaid cash item that was paid in a prior period); plus

(g) the amount of any minority interest expense consisting of Subsidiary income attributable to minority equity interests of third parties in any non-Wholly Owned Subsidiary deducted (and not added back) in such period in calculating Consolidated Net Income; plus

(h) the amount of management, monitoring, consulting and advisory fees and related indemnities and expenses paid in such period to the Sponsors to the extent otherwise permitted under Section 9.9 hereof and deducted (and not added back) in calculating Consolidated Net Income; plus

(i) the amount of net cost savings projected by the Borrower in good faith to be realized as a result of specified actions taken or to be taken prior to or during such period (calculated on a pro forma basis as though such cost savings had been realized on the first day of such period and added to EBITDA until fully realized), net of the amount of actual benefits realized during such period from such actions; provided that (w) such cost savings are reasonably identifiable and factually supportable, (x) such actions have been taken or are to be taken within 12 months after the date of determination to take such action and some portion of the benefit is expected to be realized within 12 months of taking such action, (y) no cost savings shall be added pursuant to this clause (i) to the extent duplicative of any expenses or charges relating to such cost savings that are included in clause (e) above with respect to such period and (z) the aggregate amount of cost savings added pursuant to this clause (i) shall not exceed $150,000,000 for any four consecutive quarter period (which adjustments may be incremental to pro forma adjustments made pursuant to the second paragraph of the definition of “ Fixed Charge Coverage Ratio ”); plus

(j) the amount of loss on sales of receivables and related assets to the Receivables Subsidiary in connection with a Receivables Facility deducted (and not added back) in calculating Consolidated Net Income; plus

(k) any costs or expense incurred by the Borrower or a Restricted Subsidiary pursuant to any management equity plan or stock option plan or any other management or employee benefit plan or agreement or any stock subscription or shareholder agreement, to the extent that such cost or expenses are funded with cash proceeds contributed to the capital of the

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Borrower or net cash proceeds of an issuance of Equity Interests (other than Disqualified Stock) of the Borrower (or any direct or indirect parent thereof) solely to the extent that such net cash proceeds are excluded from the calculation provided in clause (3) of Section 9.5(a) hereof; plus

(l) Expenses Relating to a Unit Outage; provided that the only Expenses Relating to a Unit Outage that may be included in EBITDA shall be, without duplication (i) up to $250,000,000 per fiscal year of Expenses Relating to a Unit Outage incurred within the first 12 months after any planned or unplanned outage of any Unit by reason of any action by any regulatory body or other Government Authority or to comply with any applicable law and (ii) up to $100,000,000 per fiscal year of Expenses Relating to a Unit Outage incurred within the first 12 months after any planned outage of any Unit for purposes of expanding or upgrading such Unit; plus

(m) cash receipts (or any netting arrangements resulting in increased cash receipts) not added in arriving at EBITDA or Consolidated Net Income in any period to the extent the non-cash gains relating to such receipts were deducted in the calculation of EBITDA pursuant to paragraph (2) below for any previous period and not added; and

(2) decreased by (without duplication) (a) non-cash gains increasing Consolidated Net Income of such Person for such period, excluding any non-cash gains to the extent they represent the reversal of an accrual or reserve for a potential cash item that reduced EBITDA in any prior period, (b) cash expenditures (or any netting arrangements resulting in increased cash expenditures) not deducted in arriving at EBITDA or Consolidated Net Income in any period to the extent non-cash losses relating to such expenditures were added in the calculation of EBITDA pursuant to paragraph (1) above for any previous period and not deducted, and (c) the amount of any minority interest income consisting of Subsidiary losses attributable to minority equity interests of third parties in any non-Wholly Owned Subsidiary to the extent such minority interest income is included in Consolidated Net Income.

“ Employee Benefit Plan ” shall mean an employee benefit plan (as defined in Section 3(3) of ERISA), other than a Foreign Plan, that is maintained or contributed to by the Borrower or any Subsidiary (or, with respect to an employee benefit plan subject to Title IV of ERISA, any ERISA Affiliate).

“ EMU ” shall mean the economic and monetary union as contemplated in the Treaty on European Union.

“ Energy Future Holding Company ” shall mean Energy Future Intermediate Holding Company LLC, a Delaware limited liability company.

“ Engagement Letter ” shall mean the amended and restated Engagement Letter, dated as of July 20, 2007, as amended by that certain Letter Agreement dated October 10, 2007, among TCEH (as successor in interest to Merger Sub), Citigroup Global Markets Inc., Credit Suisse Securities (USA) LLC, Goldman, Sachs & Co., J.P. Morgan Securities Inc., Lehman Brothers Inc. and Morgan Stanley & Co. Incorporated.

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“ Environmental CapEx Debt ” shall mean Indebtedness of the Borrower or any of its Restricted Subsidiaries incurred for the purpose of financing Environmental Capital Expenditures.

“ Environmental Capital Expenditures ” shall mean capital expenditures deemed necessary by the Borrower or its Restricted Subsidiaries to comply with, or in anticipation of having to comply with, Environmental Law or otherwise undertaken voluntarily by the Borrower or any of its Restricted Subsidiaries in connection with environmental matters.

“ Environmental Claims ” shall mean any and all actions, suits, proceedings, orders, decrees, demands, demand letters, claims, liens, notices of noncompliance, violation or potential responsibility or investigation (other than reports prepared by or on behalf of the Borrower or any Subsidiary of the Borrower (a) in the ordinary course of such Person’s business or (b) as required in connection with a financing transaction or an acquisition or disposition of Real Estate) or proceedings relating in any way to any Environmental Law or any permit issued, or any approval given, under any such Environmental Law (hereinafter, “ Claims ”), including (i) any and all Claims by Government Authorities for enforcement, cleanup, removal, response, remedial or other actions or damages pursuant to any applicable Environmental Law and (ii) any and all Claims by any third party seeking damages, contribution, indemnification, cost recovery, compensation or injunctive relief relating to the presence, release or threatened release into the environment of Hazardous Materials or arising from alleged injury or threat of injury to human health or safety (to the extent relating to human exposure to Hazardous Materials) or to the environment, including ambient air, indoor air, surface water, groundwater, land surface and subsurface strata and natural resources such as wetlands.

“ Environmental Law ” shall mean any applicable Federal, state, foreign or local statute, law, rule, regulation, ordinance, code and rule of common law now or hereafter in effect and in each case as amended, and any binding judicial or administrative interpretation thereof, including any binding judicial or administrative order, consent decree or judgment, relating to the protection of the environment, including ambient air, indoor air, surface water, groundwater, land surface and sub-surface strata and natural resources such as wetlands, or to human health or safety (to the extent relating to human exposure to Hazardous Materials), or Hazardous Materials.

“ Equity Contribution ” shall have the meaning provided in the recitals to this Agreement.

“ Equity Interests ” shall mean Capital Stock and all warrants, options or other rights to acquire Capital Stock, but excluding any debt security that is convertible into, or exchangeable for, Capital Stock.

“ Equity Offering ” shall mean any public or private sale of common stock or Preferred Stock of the Borrower or any of its direct or indirect parent companies (excluding Disqualified Stock), other than:

(1) public offerings with respect to the Borrower’s or any direct or indirect parent company’s common stock registered on Form S-8;

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(2) issuances to any Subsidiary of the Borrower; and

(3) any such public or private sale that constitutes an Excluded Contribution.

“ ERCOT ” shall mean the Electric Reliability Council of Texas.

“ ERISA ” shall mean the Employee Retirement Income Security Act of 1974, as amended from time to time. Section references to ERISA are to ERISA as in effect at the date of this Agreement and any subsequent provisions of ERISA amendatory thereof, supplemental thereto or substituted therefor.

“ ERISA Affiliate ” shall mean each person (as defined in Section 3(9) of ERISA) that together with the Borrower or any Subsidiary of the Borrower would be deemed to be a “single employer” within the meaning of Section 414(b) or (c) of the Code or, solely for purposes of Section 302 of ERISA and Section 412 of the Code, is treated as a single employer under Section 414 of the Code.

“ euro ” shall mean the single currency of participating member states of the EMU.

“ Event of Default ” shall have the meaning provided in Section 11 .

“ Excess Proceeds ” shall have the meaning provided in Section 9.8(c) hereof.

“ Exchange Act ” shall mean the Securities Exchange Act of 1934, as amended, and the rules and regulations of the SEC promulgated thereunder.

“ Exchange Date ” shall have the meaning provided in Section 2.14(b)(i) .

“ Exchange Notice ” shall have the meaning provided in Section 2.14(b)(ii) .

“ Excluded Contribution ” shall mean net cash proceeds, marketable securities or Qualified Proceeds received by the Borrower after the Closing Date from

(1) contributions to its common equity capital, and

(2) the sale (other than to a Subsidiary of the Borrower or to any management equity plan or stock option plan or any other management or employee benefit plan or agreement of the Borrower) of Capital Stock (other than Disqualified Stock and Designated Preferred Stock) of the Borrower,

in each case designated as Excluded Contributions pursuant to an Officer’s Certificate executed by the principal financial officer of the Borrower on the date such capital contributions are made or the date such Equity Interests are sold, as the case may be, which are excluded from the calculation provided in clause (3) of Section 9.5(a) hereof.

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“ Excluded Taxes ” shall mean, with respect to any Agent or any Lender, (a) net income taxes and franchise and excise taxes (imposed in lieu of net income taxes) imposed on such Agent or Lender, (b) any Taxes imposed on any Agent or any Lender as a result of any current or former connection between such Agent or Lender and the jurisdiction of the Government Authority imposing such tax or any political subdivision or taxing authority thereof or therein (other than any such connection arising from such Agent or Lender having executed, delivered or performed its obligations or received a payment under, or having been a party to or having enforced, this Agreement or any other Loan Document), (c) any U. S. federal withholding tax that is imposed on amounts payable to any Lender under the law in effect at the time such Lender becomes a party to this Agreement; provided that this subclause (c)  shall not apply to the extent that (x) the indemnity payments or additional amounts any Lender would be entitled to receive (without regard to this subclause (c) ) do not exceed the indemnity payment or additional amounts that the person making the assignment, participation or transfer to such Lender would have been entitled to receive in the absence of such assignment or (y) any Tax is imposed on a Lender in connection with an interest in any Loan or other obligation that such Lender was required to acquire pursuant to Section 13.8(a) or that such Lender acquired pursuant to Section 13.7 (it being understood and agreed, for the avoidance of doubt, that any withholding tax imposed on a Lender as a result of a Change in Law occurring after the time such Lender became a party to this Agreement (or designates a new lending office) shall not be an Excluded Tax) and (d) any Tax to the extent attributable to such Lender’s failure to comply with Section 5.4(d) and (e)  (in the case of any Non-U.S. Lender) or Section 5.4(h) (in the case of a U.S. Lender).

“ Existing Notes ” shall mean

Pollution Control Revenue Bonds—Brazos River Authority:

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Pollution Control Revenue Bonds—Sabine River Authority of Texas:

Pollution Control Revenue Bonds—Trinity River Authority of Texas:

in each case to the extent outstanding on the Closing Date.

“ Existing Notes Indentures ” shall mean each of the indentures or other documents containing the terms of the Existing Notes.

“ Existing Oncor Notes ” shall mean:

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“ Expenses Relating to a Unit Outage ” shall mean any expenses or other charges as a result of any outage or shut-down of any Unit, including any expenses or charges relating to (a) restarting any such Unit so that it may be placed back in service after such outage or shut-down, (b) purchases of power, natural gas or heat rate to meet commitments to sell, or offset a short position in, power, natural gas or heat rate that would otherwise have been met or offset from production generated by such Unit during the period of such outage or shut-down, net of the expenses not in fact incurred (including fuel and other operating expenses) that would have been incurred absent such outage or shut down and (c) starting up, operating, maintaining and shutting down any other Unit that would not otherwise have been operating absent such outage or shut-down, including the fuel and other operating expenses to the extent in excess of the expenses not in fact incurred (including fuel and other operating costs) that would have been incurred absent such outage or shut down, incurred to start-up, operate, maintain and shut-down such Unit and that are required during the period of time that the shut-down or outaged Unit is out of service in order to meet the commitments of such shut-down or outaged Unit to sell, or offset a short position in, power, natural gas or heat rate.

“ Federal Funds Effective Rate ” shall mean, for any day, the weighted average of the per annum rates on overnight federal funds transactions with members of the Federal Reserve System arranged by federal funds brokers on such day, as published on the next succeeding Business Day by the Federal Reserve Bank of New York; provided that (a) if such day is not a Business Day, the Federal Funds Effective Rate for such day shall be such rate on such transactions on the next preceding Business Day as so published on the next succeeding Business Day, and (b) if no such rate is so published on such next succeeding Business Day, the Federal Funds Effective Rate for such day shall be the average rate (rounded upward, if necessary, to a whole multiple of 1/100 of 1%) charged to the Administrative Agent on such day on such transactions as determined by the Administrative Agent.

“ Fee Letter ” shall mean the amended and restated fee letter, dated July 20, 2007, and as amended pursuant to that certain Letter Agreement dated October 10, 2007, among TCEH (as successor in interest to Merger Sub) and Citigroup Global Markets Inc., Credit Suisse Cayman Islands Branch, Credit Suisse Securities (USA) LLC, Goldman Sachs Credit Partners L.P., JPMorgan Chase Bank, N.A., J.P. Morgan Securities Inc., Lehman Commercial Paper Inc., Lehman Brothers Commercial Bank and Lehman Brothers Holdings Inc., Lehman Brothers Inc. and Morgan Stanley Senior Funding, Inc.

“ Fees ” shall mean all amounts payable pursuant to, or referred to in, Section 4.1 .

“ Fixed Charge Coverage Ratio ” shall mean, with respect to any Person for any period, the ratio of EBITDA of such Person for such period to the Fixed Charges of such Person for such period. In the event that the Borrower or any Restricted Subsidiary incurs, assumes, guarantees, redeems, retires or extinguishes any Indebtedness (other than Indebtedness incurred under any revolving credit facility unless such Indebtedness has been permanently repaid and has not been replaced) or issues or redeems Disqualified Stock or Preferred Stock subsequent to the commencement of the period for which the Fixed Charge Coverage Ratio is being calculated but prior to or simultaneously with the event for which the calculation of the Fixed Charge Coverage Ratio is made (the “ Fixed Charge Coverage Ratio Calculation Date ”), then the Fixed Charge Coverage Ratio shall be calculated giving pro forma effect to such incurrence, assumption, guarantee, redemption, retirement or extinguishment of Indebtedness, or such issuance or redemption of Disqualified Stock or Preferred Stock, as if the same had occurred at the beginning of the applicable four-quarter period.

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For purposes of making the computation referred to above, Investments, acquisitions, dispositions, mergers, consolidations and disposed operations (as determined in accordance with GAAP) that have been made by the Borrower or any of its Restricted Subsidiaries during the four-quarter reference period or subsequent to such reference period and on or prior to or simultaneously with the Fixed Charge Coverage Ratio Calculation Date shall be calculated on a pro forma basis assuming that all such Investments, acquisitions, dispositions, mergers, consolidations and disposed operations (and the change in any associated fixed charge obligations and the change in EBITDA resulting therefrom) had occurred on the first day of the four-quarter reference period. If, since the beginning of such period, any Person that subsequently became a Restricted Subsidiary or was merged with or into the Borrower or any of its Restricted Subsidiaries since the beginning of such period shall have made any Investment, acquisition, disposition, merger, consolidation or disposed operation that would have required adjustment pursuant to this definition, then the Fixed Charge Coverage Ratio shall be calculated giving pro forma effect thereto for such period as if such Investment, acquisition, disposition, merger, consolidation or disposed operation had occurred at the beginning of the applicable four-quarter period.

For purposes of this definition, whenever pro forma effect is to be given to a transaction, the pro forma calculations shall be made in good faith by a responsible financial or accounting officer of the Borrower. If any Indebtedness bears a floating rate of interest and is being given pro forma effect, the interest on such Indebtedness shall be calculated as if the rate in effect on the Fixed Charge Coverage Ratio Calculation Date had been the applicable rate for the entire period (taking into account any Hedging Obligations applicable to such Indebtedness). Interest on a Capitalized Lease Obligation shall be deemed to accrue at an interest rate reasonably determined by a responsible financial or accounting officer of the Borrower to be the rate of interest implicit in such Capitalized Lease Obligation in accordance with GAAP. For purposes of making the computation referred to above, interest on any Indebtedness under a revolving credit facility computed on a pro forma basis shall be computed based upon the average daily balance of such Indebtedness during the applicable period except as provided in the first paragraph of this definition. Interest on Indebtedness that may optionally be determined at an interest rate based upon a factor of a prime or similar rate, a eurocurrency interbank offered rate or other rate shall be deemed to have been based upon the rate actually chosen, or, if none, then based upon such optional rate chosen as the Borrower may designate.

“ Fixed Charges ” shall mean, with respect to any Person for any period, the sum of:

(1) Consolidated Interest Expense of such Person for such period;

(2) all cash dividends or other distributions paid (excluding items eliminated in consolidation) on any series of Preferred Stock during such period; and

(3) all cash dividends or other distributions paid (excluding items eliminated in consolidation) on any series of Disqualified Stock during such period.

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“ Foreign Plan ” shall mean any employee benefit plan, program, policy, arrangement or agreement maintained or contributed to by the Borrower or any of its Subsidiaries with respect to employees employed outside the United States.

“ Foreign Subsidiary ” shall mean, with respect to any Person, any Restricted Subsidiary of such Person that is not organized or existing under the laws of the United States, any state or territory thereof or the District of Columbia and any Restricted Subsidiary of such Foreign Subsidiary.

“ Fund ” shall mean any Person (other than a natural person) that is (or will be) engaged in making, purchasing, holding or otherwise investing in commercial loans and similar extensions of credit in the ordinary course.

“ GAAP ” shall mean generally accepted accounting principles in the United States which are in effect on the Closing Date.

“ Government Authority ” shall mean any nation or government, any state, province, territory or other political subdivision thereof, and any entity exercising executive, legislative, judicial, regulatory or administrative functions of or pertaining to government, including without limitation ERCOT.

“ Granting Lender ” shall have the meaning provided in Section 13.6(g) .

“ guarantee ” shall mean a guarantee (other than by endorsement of negotiable instruments for collection in the ordinary course of business), direct or indirect, in any manner (including letters of credit and reimbursement agreements in respect thereof), of all or any part of any Indebtedness or other obligations.

“ Guarantee ” shall mean (a) the Guarantee made by each Guarantor in favor of the Administrative Agent for the benefit of the Guaranteed Parties, substantially in the form of Exhibit B , and (b) any other guarantee of the Obligations made by a Restricted Subsidiary that is a Domestic Subsidiary in form and substance reasonably acceptable to the Administrative Agent.

“ Guaranteed Parties ” shall mean the Administrative Agent, any other Agent and each Lender, in each case, with respect to the Obligations or any Guarantee, and each sub-agent appointed by the Administrative Agent pursuant to Section 12 with respect to matters relating to the Obligations.

“ Guarantor ” shall mean US Holdings, Energy Future Holding Company and each other Restricted Subsidiary that provides a Guarantee hereunder pursuant to Section 9.13 or otherwise.

“ Hazardous Materials ” shall mean (a) any petroleum or petroleum products, radioactive materials, friable asbestos, urea formaldehyde foam insulation, transformers or other equipment that contain dielectric fluid containing regulated levels of polychlorinated biphenyls and radon gas; (b) any chemicals, materials or substances defined as or included in the definition of “hazardous substances,” “toxic substances,” “toxic pollutants,” “contaminants,” or “pollutants” or words of similar import, under any applicable Environmental Law; and (c) any other chemical, material or substance, which is prohibited, limited or regulated by any Environmental Law.

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“ Hedging Obligations ” shall mean with respect to any Person, the obligations of such Person under (a) any and all rate swap transactions, basis swaps, credit derivative transactions, forward rate transactions, commodity swaps, commodity options, forward commodity contracts, equity or equity index swaps or options, bond or bond price or bond index swaps or options or forward bond or forward bond price or forward bond index transactions, interest rate options, forward foreign exchange transactions, cap transactions, floor transactions, collar transactions, currency swap transactions, cross-currency rate swap transactions, currency options, spot contracts, or any other similar transactions or any combination of any of the foregoing (including any options to enter into any of the foregoing), whether or not any such transaction is governed by or subject to any master agreement, (b) any and all transactions of any kind, and the related confirmations, which are subject to the terms and conditions of, or governed by, any form of master agreement published by the International Swaps and Derivatives Association, Inc., any International Foreign Exchange Master Agreement or any other master agreement (any such master agreement, together with any related schedules, a “ Master Agreement ”), including any such obligations or liabilities under any Master Agreement and (c) physical or financial commodity contracts or agreements, power purchase or sale agreements, fuel purchase or sale agreements, environmental credit purchase or sale agreements, power transmission agreements, commodity transportation agreements, fuel storage agreements, netting agreements (including Netting Agreements), capacity agreement and commercial or trading agreements, each with respect to the purchase, sale, exchange of (or the option to purchase, sell or exchange), Covered Commodity price or price indices for any such Covered Commodity or services or any other similar derivative agreements, and any other similar agreements.

“ Historical Financial Statements ” shall mean, as of the Closing Date, (a) the audited consolidated balance sheets of the Borrower as of December 31, 2004, December 31, 2005 and December 31, 2006 and the audited consolidated statements of income, stockholders’ equity and cash flows of the Borrower for each of the fiscal years in the three year period ending on December 31, 2006 and (b) the unaudited consolidated balance sheets of the Borrower for each subsequent fiscal quarter ended at least 45 days before the Closing Date and the unaudited consolidated statements of income, stockholders’ equity and cash flows of the Borrower for each such fiscal quarter.

“ Holdings ” shall mean Texas Energy Future Holdings Limited Partnership, a Delaware limited partnership and its successors.

“ Incremental Deposit L/C Loans ” shall mean Incremental Deposit L/C Loans under, and as defined in, the TCEH Senior Secured Facilities.

“ Indebtedness ” shall mean, with respect to any Person, without duplication:

(1) any indebtedness (including principal and premium) of such Person, whether or not contingent:

(a) in respect of borrowed money;

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(b) evidenced by bonds, notes, debentures or similar instruments or letters of credit or bankers’ acceptances (or, without duplication, reimbursement agreements in respect thereof);

(c) representing the balance deferred and unpaid of the purchase price of any property (including Capitalized Lease Obligations), except (i) any such balance that constitutes a trade payable or similar obligation to a trade creditor, in each case accrued in the ordinary course of business and (ii) any earn-out obligations until such obligation becomes a liability on the balance sheet of such Person in accordance with GAAP; or

(d) representing any Hedging Obligations;

if and to the extent that any of the foregoing Indebtedness (other than letters of credit and Hedging Obligations) would appear as a liability upon a balance sheet (excluding the footnotes thereto) of such Person prepared in accordance with GAAP;

(2) to the extent not otherwise included, any obligation by such Person to be liable for, or to pay, as obligor, guarantor or otherwise on, the obligations of the type referred to in clause (1) of a third Person (whether or not such items would appear upon the balance sheet of the such obligor or guarantor), other than by endorsement of negotiable instruments for collection in the ordinary course of business; and

(3) to the extent not otherwise included, the obligations of the type referred to in clause (1) of a third Person secured by a Lien on any asset owned by such first Person, whether or not such Indebtedness is assumed by such first Person; provided that the amount of Indebtedness of such first Person for purposes of this clause (3) shall be deemed to be equal to the lesser of (i) the aggregate unpaid amount of such Indebtedness and (ii) the fair market value of the property encumbered thereby as determined by such first Person in good faith;

provided , however , that notwithstanding the foregoing, Indebtedness shall be deemed not to include (a) Contingent Obligations incurred in the ordinary course of business or (b) obligations under or in respect of Receivables Facilities or (c) amounts payable by and between the Borrower and its Subsidiaries in connection with retail clawback or other regulatory transition issues.

“ indemnified liabilities ” shall have the meaning provided in Section 13.5 .

“ Indemnified Taxes ” shall mean all Taxes (including Other Taxes) other than (i) Excluded Taxes and (ii) any interest, penalties or expenses caused by an Agent’s or Lender’s gross negligence or willful misconduct.

“ Independent Financial Advisor ” shall mean an accounting, appraisal, investment banking firm or consultant to Persons engaged in Similar Businesses of nationally recognized standing that is, in the good faith judgment of the Borrower, qualified to perform the task for which it has been engaged.

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“ Initial Investors ” shall have the meaning provided in the recitals to this Agreement.

“ Interest Election Notice ” shall have the meaning provided in Section 2.8(c) .

“ Interest Period ” shall mean, with respect to any Loan, the interest period applicable thereto, as determined pursuant to Section 2.9 .

“ Interim Loan Conversion Date ” shall mean October 10, 2008 or, if such date is not a Business Day, the next succeeding Business Day.

“ Investment Grade Rating ” shall mean a rating equal to or higher than Baa3 (or the equivalent) by Moody’s and BBB- (or the equivalent) by S&P, or an equivalent rating by any other Rating Agency.

“ Investment Grade Securities ” shall mean:

(1) securities issued or directly and fully guaranteed or insured by the United States government or any agency or instrumentality thereof (other than Cash Equivalents);

(2) debt securities or debt instruments with an Investment Grade Rating, but excluding any debt securities or instruments constituting loans or advances among the Borrower and its Subsidiaries;

(3) investments in any fund that invests exclusively in investments of the type described in clauses (1) and (2) which fund may also hold immaterial amounts of cash pending investment or distribution; and

(4) corresponding instruments in countries other than the United States customarily utilized for high quality investments.

“ Investments ” shall mean, with respect to any Person, all investments by such Person in other Persons (including Affiliates) in the form of loans (including guarantees), advances or capital contributions (excluding accounts receivable, trade credit, advances to customers, commissions, travel and similar advances to officers and employees, in each case made in the ordinary course of business), purchases or other acquisitions for consideration of Indebtedness, Equity Interests or other securities issued by any other Person and investments that are required by GAAP to be classified on the balance sheet (excluding the footnotes) of the Borrower in the same manner as the other investments included in this definition to the extent such transactions involve the transfer of cash or other property. For purposes of the definition of “ Unrestricted Subsidiary ” and Section 9.5 hereof:

(1) “ Investments ” shall include the portion (proportionate to the Borrower’s equity interest in such Subsidiary) of the fair market value of the net assets of a Subsidiary of the Borrower at the time that such Subsidiary is designated an Unrestricted Subsidiary; provided , however , that upon a redesignation of such Subsidiary as a Restricted Subsidiary, the Borrower shall be deemed to continue to have a permanent “ Investment ” in an Unrestricted Subsidiary in an amount (if positive) equal to:

(a) the Borrower’s “ Investment ” in such Subsidiary at the time of such redesignation; less

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(b) the portion (proportionate to the Borrower’s equity interest in such Subsidiary) of the fair market value of the net assets of such Subsidiary at the time of such redesignation; and

(2) any property transferred to or from an Unrestricted Subsidiary shall be valued at its fair market value at the time of such transfer, in each case as determined in good faith by the Borrower.

“ Joint Lead Arrangers and Bookrunners ” shall mean Morgan Stanley Senior Funding Inc., Goldman Sachs Credit Partners L.P., Citibank, N.A., Credit Suisse Securities (USA) LLC, J.P. Morgan Chase Bank N.A. Inc. and Lehman Brothers Inc.

“ KKR ” shall mean each of Kohlberg Kravis Roberts & Co., L.P.

“ Lender ” and “ Lenders ” shall have the meanings provided in the preamble to this Agreement.

“ Lender Default ” shall mean (a) the failure (which has not been cured) of a Lender to make available its portion of any Borrowing that it is required to make hereunder or (b) a Lender having notified the Administrative Agent and/or the Borrower that it does not intend to comply with the obligations under Section 2.1(a) , or (c) a Lender being deemed insolvent or becoming the subject of a bankruptcy or insolvency proceeding.

“ LIBOR Loan ” shall mean any Loan bearing interest at a rate determined by reference to the LIBOR Rate.

“ LIBOR Rate ” shall mean, for any Interest Period with respect to a LIBOR Loan, the rate per annum equal to the British Bankers Association LIBOR Rate (“ BBA LIBOR ”), as published by Reuters (or other commercially available source providing quotations of BBA LIBOR as designated by the Administrative Agent from time to time) at approximately 11:00 a.m., London time, two Business Days prior to the commencement of such Interest Period, for deposits in Dollars (for delivery on the first day of such Interest Period) with a term equivalent to such Interest Period. If such rate is not available at such time for any reason, then the “ LIBOR Rate ” for such Interest Period shall be the rate per annum as may be agreed by the Borrower and the Administrative Agent to be a rate at which deposits in Dollars for delivery on the first day of such Interest Period in same day funds in the approximate amount of the LIBOR Loan being made, continued or converted by the Administrative Agent and with a term equivalent to such Interest Period would be offered by the Administrative Agent’s London Branch to major banks in the applicable London interbank eurocurrency market at their request at approximately 11:00 a.m. (London time) two Business Days prior to the commencement of such Interest Period.

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“ Lien ” shall mean, with respect to any asset, any mortgage, lien (statutory or otherwise), pledge, hypothecation, charge, security interest, preference, priority or encumbrance of any kind in respect of such asset, whether or not filed, recorded or otherwise perfected under Applicable Laws, including any conditional sale or other title retention agreement, any lease in the nature thereof, any option or other agreement to sell or give a security interest in and any filing of or agreement to give any financing statement under the Uniform Commercial Code (or equivalent statutes) of any jurisdiction; provided that in no event shall an operating lease be deemed to constitute a Lien.

“ Loan ” shall mean any Senior Interim Loan or Senior Term Loan made by any Lender hereunder and any Loan made as a result of the accrual of PIK Interest.

“ Loan Documents ” shall mean this Agreement, the Guarantee, and any promissory notes issued by the Borrower hereunder.

“ Loan Parties ” shall mean the Borrower and the Guarantors.

“ Master Agreement ” shall have the meaning provided in the definition of the term “Hedging Obligations”.

“ Material Adverse Effect ” shall mean any circumstances or conditions affecting the business, assets, operations, properties or financial condition of the Borrower and its Subsidiaries, taken as a whole, that would, individually or in the aggregate, materially adversely affect (a) the ability of the Borrower and the other Loan Parties, taken as a whole, to perform their payment obligations under this Agreement or any of the other Loan Documents or (b) the rights and remedies of the Administrative Agent and the Lenders under this Agreement or any of the other Loan Documents.

“ Material Subsidiary ” shall mean, at any date of determination, each Restricted Subsidiary that is a Subsidiary of TCEH (a) whose total assets (when combined with the assets of such Restricted Subsidiary’s Subsidiaries, after eliminating intercompany obligations) at the last day of the most recent Test Period for which Section 9.1 Financials have been delivered were equal to or greater than 2.5% of the Consolidated Total Assets of the Borrower and the Restricted Subsidiaries of the Borrower at such date or (b) whose total revenues (when combined with the revenues of such Restricted Subsidiary’s Subsidiaries after eliminating intercompany indebtedness) during such Test Period were equal to or greater than 2.5% of the consolidated revenues of the Borrower and the Restricted Subsidiaries of the Borrower for such period, in each case determined in accordance with GAAP; provided that if, at any time and from time to time after the Closing Date, Restricted Subsidiaries of the Borrower that are not Material Subsidiaries have, in the aggregate, (x) total assets (when combined with the assets of such Restricted Subsidiary’s Subsidiaries, after eliminating intercompany obligations) at the last day of such Test Period equal to or greater than 10.0% of the Consolidated Total Assets of the Borrower and the Restricted Subsidiaries of the Borrower at such date or (y) total revenues (when combined with the revenues of such Restricted Subsidiary’s Subsidiaries, after eliminating intercompany obligations) during such Test Period equal to or greater than 10.0% of the consolidated revenues of the Borrower and the Restricted Subsidiaries of the Borrower for such period, in each case determined in accordance with GAAP, then the Borrower shall, on the date on which financial statements for such quarter are delivered pursuant to this Agreement, designate in writing to the Administrative Agent one or more of such Restricted Subsidiaries as “Material Subsidiaries” so that such condition no longer exists. It is agreed and understood that no Receivables Subsidiary shall be a Material Subsidiary.

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“ Maturity Date ” shall mean (a) if the Loans have not been converted to Senior Term Loans, October 10, 2008 or, if such date is not a Business Day, the next succeeding Business Day, or (b) if the Loans have been converted to Senior Term Loans, October 10, 2017 or, if such date is not a Business Day, the next succeeding Business Day (with respect to clause (b) only, the “ Term Loan Maturity Date ”).

“ Merger ” shall have the meaning provided in the recitals to this Agreement.

“ Merger Funds ” shall have the meaning provided in the recitals to this Agreement.

“ Merger Sub ” shall mean Texas Energy Future Merger Sub Corp, a Texas corporation.

“ Minimum Equity Amount ” shall have the meaning provided in the recitals to this Agreement.

“ Moody’s ” shall mean Moody’s Investors Service, Inc. and any successor to its rating agency business.

“ Multiemployer Plan ” shall mean a plan that is a multiemployer plan as defined in Section 4001(a)(3) of ERISA (i) to which any of the Borrower, any Subsidiary of the Borrower or any ERISA Affiliate is then making or has an obligation to make contributions or (ii) with respect to which the Borrower, any Subsidiary of the Borrower or any ERISA Affiliate could incur liability pursuant to Title IV of ERISA.

“Necessary CapEx Debt” shall mean Indebtedness of the Borrower or any of its Restricted Subsidiaries incurred for the purpose of financing Necessary Capital Expenditures.

“Necessary Capital Expenditures” shall mean capital expenditures by the Borrower and its Restricted Subsidiaries that are required by applicable law (other than Environmental Law) or otherwise undertaken voluntarily for health and safety reasons (other than as required by Environmental Law). The term “Necessary Capital Expenditures” does not include any capital expenditure undertaken primarily to increase the efficiency of, expand or re-power any power generation facility.

“ Net Asset Sale Proceeds ” shall mean the aggregate cash proceeds received by the Borrower or any of its Restricted Subsidiaries in respect of any Asset Sale (including a Casualty Event), including any cash received upon the sale or other disposition of any Designated Non-Cash Consideration received in any Asset Sale (including a Casualty Event), net of the direct costs relating to such Asset Sale (including a Casualty Event) and the sale or disposition of such Designated Non-Cash Consideration, including legal, accounting and investment banking fees, and brokerage and sales commissions, any relocation expenses incurred as a result thereof, taxes paid or payable as a result thereof (after taking into account any available tax credits or deductions and any tax sharing arrangements), amounts required to be

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applied to the repayment of principal, premium, if any, and interest on Senior Indebtedness required (other than required by clause (1)  of Section 9.8(b) hereof) to be paid as a result of such transaction and any deduction of appropriate amounts to be provided by the Borrower or any of its Restricted Subsidiaries as a reserve in accordance with GAAP against any liabilities associated with the asset disposed of in such transaction and retained by the Borrower or any of its Restricted Subsidiaries after such sale or other disposition thereof, including pension and other post-employment benefit liabilities and liabilities related to environmental matters or against any indemnification obligations associated with such transaction.

“ Net Cash Proceeds ” shall mean, with respect to any Debt Incurrence Prepayment Event, (a) the gross cash proceeds (including payments from time to time in respect of installment obligations, if applicable) received by or on behalf of the Borrower or any of the Restricted Subsidiaries in respect of such Debt Incurrence Prepayment Event, as the case may be, less (b) the sum of:

(i) the amount, if any, of all taxes paid or estimated to be payable by the Borrower or any of the Restricted Subsidiaries in connection with such Debt Incurrence Prepayment Event, and

(ii) reasonable and customary fees paid by the Borrower or a Restricted Subsidiary in connection with the foregoing,

in each case only to the extent not already deducted in arriving at the amount referred to in clause (a)  above.

“ Net Income ” shall mean, with respect to any Person, the net income (loss) of such Person, determined in accordance with GAAP and before any reduction in respect of Preferred Stock dividends.

“ Netting Agreement ” shall mean a netting agreement, master netting agreement or other similar document having the same effect as a netting agreement or master netting agreement and, as applicable, any collateral annex, security agreement or other similar document related to any master netting agreement or Permitted Contract.

“ Non-Consenting Lender ” shall have the meaning provided in Section 13.7(b) .

“ Non-Defaulting Lender ” shall mean and include each Lender other than a Defaulting Lender.

“ Non-U.S. Lender ” shall mean any Agent or Lender that is not, for United States federal income tax purposes, (a) an individual who is a citizen or resident of the United States, (b) a corporation, partnership or entity treated as a corporation or partnership created or organized in or under the laws of the United States, or any political subdivision thereof, (c) an estate whose income is subject to U.S. federal income taxation regardless of its source or (d) a trust if a court within the United States is able to exercise primary supervision over the administration of such trust and one or more United States persons have the authority to control all substantial decisions of such trust or a trust that has a valid election in effect under applicable U. S. Treasury regulations to be treated as a United States person.

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“ Notice of Borrowing ” shall have the meaning provided in Section 2.3(a) .

“ Notice of Conversion or Continuation ” shall have the meaning provided in Section 2.6 .

“ Obligations ” shall mean any principal, interest (including any interest accruing subsequent to the filing of a petition in bankruptcy, reorganization or similar proceeding at the rate provided for in the documentation with respect thereto, whether or not such interest is an allowed claim under applicable state, federal or foreign law), premium, penalties, fees, indemnifications, reimbursements (including reimbursement obligations with respect to letters of credit and bankers’ acceptances), damages and other liabilities, and guarantees of payment of such principal, interest, penalties, fees, indemnifications, reimbursements, damages and other liabilities, payable under the documentation governing any Indebtedness.

“ Officer’s Certificate ” shall mean a certificate signed on behalf of the Borrower by an Authorized Officer of the Borrower, who must be the principal executive officer, the principal financial officer, the treasurer or the principal accounting officer of the Borrower that meets the requirements provided in this Agreement.

“ Oncor ” shall mean Oncor Electric Delivery Company LLC a Delaware limited liability company.

“ Oncor Electric Delivery Facility ” shall mean the revolving credit agreement to be entered into as of the Closing Date by and among Oncor, as borrower, the lenders party thereto in their capacities as lenders thereunder and JPMorgan Chase Bank, N.A., as Administrative Agent, including any guarantees, collateral documents, instruments and agreements executed in connection therewith, and any amendments, supplements, modifications, extensions, renewals, restatements, refundings or refinancings thereof and any indentures or credit facilities or commercial paper facilities with banks or other institutional lenders or investors that replace, refund or refinance any part of the loans, notes, other credit facilities or commitments thereunder, including any such replacement, refunding or refinancing facility or indenture that increases the amount borrowable thereunder or alters the maturity thereof.

“ Oncor Holdings ” shall mean Oncor Electric Delivery Holdings Company LLC, Delaware limited liability company.

“ Oncor Subsidiaries ” shall mean the Subsidiaries of Energy Future Holding Company, including Oncor Holdings and its Subsidiaries, all of which shall be Unrestricted Subsidiaries existing on the Closing Date.

“ Opinion of Counsel ” shall mean a written opinion from legal counsel who is acceptable to the Administrative Agent. The counsel may be an employee of or counsel to the Borrower or the Administrative Agent.

“ Optional Interest Repayment ” shall have the meaning provided in Section 5.1(b) .

“ Optional Interest Repayment Amount ” shall have the meaning provided in Section 5.1(b) .

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“ Organizational Documents ” shall mean, (a) with respect to any corporation, the certificate or articles of incorporation and the bylaws (or equivalent or comparable constitutive documents with respect to any non-U.S. jurisdiction), (b) with respect to any limited liability company, the certificate or articles of formation or organization and operating agreement; and (c) with respect to any partnership, joint venture, trust or other form of business entity, the partnership, joint venture or other applicable agreement of formation or organization and, if applicable, any agreement, instrument, filing or notice with respect thereto filed in connection with its formation or organization with the applicable Government Authority in the jurisdiction of its formation or organization and, if applicable, any certificate or articles of formation or organization of such entity.

“ Other Taxes ” shall mean any and all present or future stamp, registration, documentary or any other excise, property or similar taxes (including interest, fines, penalties, additions to tax and related expenses with regard thereto) arising from any payment made or required to be made under this Agreement or any other Loan Document or from the execution or delivery of, registration or enforcement of, consummation or administration of, or otherwise with respect to, this Agreement or any other Loan Document.

“ Overnight Rate ” shall mean, for any day, the greater of (i) the Federal Funds Effective Rate and (ii) an overnight rate determined by the Administrative Agent in accordance with banking industry rules on interbank compensation.

“ Participant ” shall have the meaning provided in Section 13.6(c) .

“ Participant Register ” shall have the meaning provided in Section 13.6(c)(iii) .

“ Patriot Act ” shall have the meaning provided in Section 13.18 .

“ Pension Act ” shall mean the Pension Protection Act of 2006, as it presently exists or as it may be amended from time to time.

“ Permitted Asset Swap ” shall mean the concurrent purchase and sale or exchange of Related Business Assets or a combination of Related Business Assets and cash or Cash Equivalents between the Borrower or any of its Restricted Subsidiaries and another Person; provided , that any cash or Cash Equivalents received must be applied in accordance with Section 9.8 hereof.

“ Permitted Holders ” shall mean each of the Sponsors, members of management (including directors) of the Borrower or its Subsidiaries who on the Closing Date are (or will be at any time prior to the first anniversary of the Closing Date) holders of Equity Interests of the Borrower (or any of its direct or indirect parent companies) and any group (within the meaning of Section 13(d)(3) or Section 14(d)(2) of the Exchange Act or any successor provision) of which any of the foregoing are members; provided that, in the case of such group and without giving effect to the existence of such group or any other group, such Sponsors and members of management, collectively, have beneficial ownership of more than 50% of the total voting power of the Voting Stock of the Borrower or any of its direct or indirect parent companies.

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“ Permitted Investments ” shall mean:

(1) any Investment in the Borrower or any of its Restricted Subsidiaries;

(2) any Investment in cash and Cash Equivalents or Investment Grade Securities;

(3) any Investment by the Borrower or any of its Restricted Subsidiaries in a Person that is engaged in a Similar Business if as a result of such Investment:

(a) such Person becomes a Restricted Subsidiary; or

(b) such Person, in one transaction or a series of related transactions, is merged or consolidated with or into, or transfers or conveys substantially all of its assets to, or is liquidated into, the Borrower or a Restricted Subsidiary,

and, in each case, any Investment held by such Person; provided that such Investment was not acquired by such Person in contemplation of such acquisition, merger, consolidation or transfer;

(4) any Investment in securities or other assets not constituting cash, Cash Equivalents or Investment Grade Securities and received in connection with an Asset Sale made pursuant to Section 9.8 or any other disposition of assets not constituting an Asset Sale;

(5) any Investment existing on the Closing Date;

(6) any Investment acquired by the Borrower or any of its Restricted Subsidiaries:

(a) in exchange for any other Investment or accounts receivable held by the Borrower or any such Restricted Subsidiary in connection with or as a result of a bankruptcy, workout, reorganization or recapitalization of the issuer of such other Investment or accounts receivable; or

(b) as a result of a foreclosure by the Borrower or any of its Restricted Subsidiaries with respect to any secured Investment or other transfer of title with respect to any secured Investment in default;

(7) Hedging Obligations permitted under clause (10)  of Section 9.7(b) ;

(8) any Investment in a Similar Business having an aggregate fair market value, taken together with all other Investments made pursuant to this clause (8) that are at that time outstanding, not to exceed (x) prior to the Interim Loan Conversion Date, $750,000,000 and (y) thereafter, 3.5% of Total Assets at the time of such Investment (in each case, with the fair market value of each Investment being measured at the time made and without giving effect to subsequent changes in value);

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(9) Investments the payment for which consists of Equity Interests (exclusive of Disqualified Stock) of the Borrower or any of its direct or indirect parent companies; provided , however , that such Equity Interests will not increase the amount available for Restricted Payments under clause (3)  of Section 9.5(a) ;

(10) guarantees of Indebtedness of the Borrower or any of its Restricted Subsidiaries permitted under Section 9.7 ;

(11) any transaction to the extent it constitutes an Investment that is permitted and made in accordance with the provisions of Section 9.9(b) (except transactions described in clauses (2) , (5)  and (9)  of Section 9.9(b) );

(12) Investments consisting of purchases and acquisitions of inventory, fuel (including all forms of nuclear fuel), supplies, material or equipment;

(13) additional Investments having an aggregate fair market value, taken together with all other Investments made pursuant to this clause (13) that are at that time outstanding (without giving effect to the sale of an Investment to the extent the proceeds of such sale do not consist of cash or marketable securities), not to exceed (x) prior to the Interim Loan Conversion date, $750,000,000 and (y) thereafter, 3.5% of Total Assets at the time of such Investment (in each case, with the fair market value of each Investment being measured at the time made and without giving effect to subsequent changes in value);

(14) Investments relating to a Receivables Subsidiary that, in the good faith determination of the Borrower, is necessary or advisable to effect any Receivables Facility for the benefit of the Borrower or any of its Restricted Subsidiaries;

(15) advances to, or guarantees of Indebtedness of, employees not in excess of $25,000,000 outstanding at any one time, in the aggregate;

(16) loans and advances to officers, directors and employees for business-related travel expenses, moving expenses and other similar expenses, in each case incurred in the ordinary course of business or consistent with past practices or to fund such Person’s purchase of Equity Interests of the Borrower or any direct or indirect parent company thereof;

(17) any Investment in any Subsidiary or any joint venture in connection with intercompany cash management arrangements or related activities arising in the ordinary course of business;

(18) any Investment in Shell Wind in an aggregate amount not to exceed (x) prior to the Interim Loan Conversion Date, $250,000,000 and (y) thereafter, $1,500,000,000; and

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(19) one or more letters of credit in an aggregate amount not to exceed $170,000,000 posted by a Restricted Subsidiary in favor of an Oncor Subsidiary to secure that Restricted Subsidiary’s contractual obligations to that Subsidiary.

“ Permitted Liens ” shall mean, with respect to any Person:

(1) pledges or deposits by such Person under workmen’s compensation laws, unemployment insurance laws or similar legislation, or good faith deposits in connection with bids, tenders, contracts (other than for the payment of Indebtedness) or leases to which such Person is a party, or deposits to secure public or statutory obligations of such Person or deposits of cash or U.S. government bonds to secure surety or appeal bonds to which such Person is a party, or deposits as security for contested taxes or import duties or for the payment of rent, in each case incurred in the ordinary course of business (including in connection with the construction or restoration of facilities for the generation, transmission or distribution of electricity) or otherwise constituting Permitted Investments;

(2) Liens imposed by law, such as carriers’, warehousemen’s and mechanics’ Liens, in each case for sums not yet overdue for a period of more than 30 days or being contested in good faith by appropriate proceedings or other Liens arising out of judgments or awards against such Person with respect to which such Person shall then be proceeding with an appeal or other proceedings for review if adequate reserves with respect thereto are maintained on the books of such Person in accordance with GAAP;

(3) Liens for taxes, assessments or other governmental charges not yet overdue for a period of more than 30 days or payable or subject to penalties for nonpayment or which are being contested in good faith by appropriate proceedings diligently conducted, if adequate reserves with respect thereto are maintained on the books of such Person in accordance with GAAP;

(4) Liens in favor of issuers of performance and surety bonds or bid bonds or with respect to other regulatory requirements or letters of credit issued pursuant to the request of and for the account of such Person in the ordinary course of its business;

(5) minor survey or title exceptions or irregularities, minor encumbrances, easements or reservations of, or rights of others for, licenses, permits, conditions, covenants, rights-of-way, sewers, electric lines, telegraph and telephone lines and other similar purposes, or zoning or other restrictions as to the use of real properties or Liens incidental to the conduct of the business of such Person or to the ownership of its properties which were not incurred in connection with Indebtedness and which do not in the aggregate materially adversely affect the value of said properties or materially impair their use in the operation of the business of such Person;

(6) Liens securing Indebtedness permitted to be incurred pursuant to clause (4) , (12)  or (13)  of Section 9.7(b) hereof; provided that (a) Liens securing Indebtedness, Disqualified Stock or Preferred Stock permitted to be incurred pursuant to clause (13)  relate only to Refinancing Indebtedness that serves to refund or refinance Indebtedness, Disqualified Stock or Preferred Stock incurred under clause (4)  or (12)  of Section 9.7(b) hereof, and (b) Liens securing Indebtedness, Disqualified Stock or Preferred Stock permitted to be incurred pursuant to clause (4)  of Section 9.7(b) hereof extend only to the assets so financed, purchased, constructed or improved;

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(7) Liens existing on the Closing Date (other than Liens in favor of the lenders under the TCEH Senior Secured Facilities);

(8) Liens on property or shares of stock of a Person at the time such Person becomes a Subsidiary; provided , however , such Liens are not created or incurred in connection with, or in contemplation of, such other Person becoming such a Subsidiary; provided , further , however , that such Liens may not extend to any other property owned by the Borrower or any of its Restricted Subsidiaries;

(9) Liens on property at the time the Borrower or a Restricted Subsidiary acquired the property, including any acquisition by shall mean of a merger or consolidation with or into the Borrower or any of its Restricted Subsidiaries; provided , however , that such Liens are not created or incurred in connection with, or in contemplation of, such acquisition; provided , further , however , that the Liens may not extend to any other property owned by the Borrower or any of its Restricted Subsidiaries;

(10) Liens securing Indebtedness or other obligations of a Restricted Subsidiary owing to the Borrower or another Restricted Subsidiary permitted to be incurred in accordance with Section 9.7 hereof;

(11) Liens securing Hedging Obligations, of the Borrower or its Restricted Subsidiaries incurred under clause (10)  of Section 9.7(b) hereof; provided that such agreements were entered into in the ordinary course of business and not for speculative purposes (as determined by the Borrower in its reasonable discretion acting in good faith) and, in the case of any commodity Hedging Obligations or any Hedging Obligation of the type described in clause (c)  of the definition of “Hedging Obligation,” entered into in order to hedge against or manage fluctuations in the price or availability of any Covered Commodity);

(12) Liens on specific items of inventory or other goods and proceeds of any Person securing such Person’s obligations in respect of bankers’ acceptances issued or created for the account of such Person to facilitate the purchase, shipment or storage of such inventory or other goods;

(13) leases, subleases, licenses or sublicenses granted to others in the ordinary course of business which do not materially interfere with the ordinary conduct of the business of the Borrower or any of its Restricted Subsidiaries;

(14) Liens arising from Uniform Commercial Code financing statement filings regarding operating leases entered into by the Borrower and its Restricted Subsidiaries in the ordinary course of business;

(15) Liens in favor of the Borrower or any Guarantor;

(16) [ Reserved ] ;

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(17) Liens on accounts receivable, other Receivables Facility assets, or accounts into which collections or proceeds of Receivables Facility assets are deposited, in each case in connection with a Receivables Facility for the benefit of the Borrower or its Restricted Subsidiaries;

(18) Liens to secure any refinancing, refunding, extension, renewal or replacement (or successive refinancing, refunding, extensions, renewals or replacements) as a whole, or in part, of any Indebtedness secured by any Lien referred to in the foregoing clauses (6), (7), (8) and (9); provided , however , that (a) such new Lien shall be limited to all or part of the same property that secured the original Lien (plus improvements on such property), and (b) the Indebtedness secured by such Lien at such time is not increased to any amount greater than the sum of (i) the outstanding principal amount or, if greater, committed amount of the Indebtedness described under clauses (6), (7), (8), and (9) at the time the original Lien became a Permitted Lien under this Agreement, and (ii) an amount necessary to pay any fees and expenses, including premiums, related to such refinancing, refunding, extension, renewal or replacement;

(19) deposits made in the ordinary course of business to secure liability to insurance carriers;

(20) other Liens securing obligations incurred in the ordinary course of business which obligations do not exceed $100,000,000 at any one time outstanding;

(21) Liens securing judgments for the payment of money not constituting an Event of Default under clause (f)  of Section 11.1 hereof so long as such Liens are adequately bonded and any appropriate legal proceedings that may have been duly initiated for the review of such judgment have not been finally terminated or the period within which such proceedings may be initiated has not expired;

(22) Liens in favor of customs and revenue authorities arising as a matter of law to secure payment of customs duties in connection with the importation of goods in the ordinary course of business;

(23) Liens (i) of a collection bank arising under Section 4-210 of the Uniform Commercial Code, or any comparable or successor provision, on items in the course of collection, and (ii) in favor of banking institutions arising as a matter of law encumbering deposits (including the right of set-off) and which are within the general parameters customary in the banking industry;

(24) Liens deemed to exist in connection with Investments in repurchase agreements permitted under Section 9.7 hereof; provided that such Liens do not extend to any assets other than those that are the subject of such repurchase agreements;

(25) ground leases or subleases, licenses or sublicenses in respect of real property on which facilities owned or leased by the Borrower or any of its Subsidiaries are located;

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(26) Liens that are contractual rights of set-off (i) relating to the establishment of depository relations with banks not given in connection with the issuance of Indebtedness, (ii) relating to pooled deposit or sweep accounts of the Borrower or any of its Restricted Subsidiaries to permit satisfaction of overdraft or similar obligations incurred in the ordinary course of business of the Borrower and its Restricted Subsidiaries or (iii) relating to purchase orders and other agreements entered into with customers of the Borrower or any of its Restricted Subsidiaries in the ordinary course of business;

(27) Liens arising out of conditional sale, title retention, consignment or similar arrangements for the sale or purchase of goods entered into by the Borrower or any Restricted Subsidiary in the ordinary course of business;

(28) rights reserved to or vested in others to take or receive any part of, or royalties related to, the power, gas, oil, coal, lignite or other minerals or timber generated, developed, manufactured or produced by, or grown on, or acquired with, any property of the Borrower or any of its Restricted Subsidiaries and Liens upon the production from property of power, gas, oil, coal, lignite or other minerals or timber, and the by-products and proceeds thereof, to secure the obligations to pay all or a part of the expenses of exploration, drilling, mining or development of such property only out of such production or proceeds;

(29) Liens arising out of all presently existing and future division and transfer orders, advance payment agreements, processing contracts, gas processing plant agreements, operating agreements, gas balancing or deferred production agreements, pooling, unitization or communitization agreements, pipeline, gathering or transportation agreements, platform agreements, drilling contracts, injection or repressuring agreements, cycling agreements, construction agreements, salt water or other disposal agreements, leases or rental agreements, farm-out and farm-in agreements, exploration and development agreements, and any and all other contracts or agreements covering, arising out of, used or useful in connection with or pertaining to the exploration, development, operation, production, sale, use, purchase, exchange, storage, separation, dehydration, treatment, compression, gathering, transportation, processing, improvement, marketing, disposal or handling of any property of the Borrower or any of its Restricted Subsidiaries, provided that such agreements are entered into in the ordinary course of business (including in respect of construction or restoration activities);

(30) any restrictions on any stock or stock equivalents or other joint venture interests of the Borrower or any of its Restricted Subsidiaries providing for a breach, termination or default under any owners, participation, shared facility, joint venture, stockholder, membership, limited liability company or partnership agreement between such Person and one or more other holders of such stock or stock equivalents or interest of such Person, if a security interest or other Lien is created on such stock or stock equivalents or interest as a result thereof and other similar Liens;

(31) [ Reserved ] ;

(32) Liens and other exceptions to title, in either case on or in respect of any facilities of the Borrower or any of its Restricted Subsidiaries, arising as a result of any shared facility agreement entered into with respect to such facility, except to the extent that any such Liens or exceptions, individually or in the aggregate, materially adversely affect the value of the relevant property or materially impair the use of the relevant property in the operation of business of the Borrower or any of its Restricted Subsidiaries, taken as a whole;

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(33) Liens on cash and Cash Equivalents (i) deposited by the Borrower or any of its Restricted Subsidiaries in margin accounts with or on behalf of brokers, credit clearing organizations, independent system operators, regional transmission organizations, pipelines, state agencies, federal agencies, futures contract brokers, customers, trading counterparties, or any other parties or issuers of surety bonds or (ii) pledged or deposited as collateral by the Borrower or any of its Restricted Subsidiaries with any of the entities described in clause (i) above to secure their respective obligations, in the case of each of clauses (i) and (ii) above, with respect to: (A) any contracts and transactions for the purchase, sale, exchange of, or the option (whether physical or financial) to purchase, sell or exchange (1) natural gas, (2) electricity, (3) coal and lignite, (4) petroleum-based liquids, (5) oil, (6) nuclear fuel (including enrichment and conversion), (7) emissions or other environmental credits, (8) waste byproducts, (9) weather, (10) power and other generation capacity, (11) heat rate, (12) congestion, (13) renewal energy credit, or (14) any other energy-related commodity or services or derivative (including ancillary services and related risk (such as location basis); (B) any contracts or transactions for the purchase, processing, transmission, transportation, distribution, sale, lease, hedge or storage of, or any other services related to any commodity or service identified in subparts (1)—(14) above, including any capacity agreement; (C) any financial derivative agreement (including but not limited to swaps, options or swaptions) related to any commodity identified in subparts (1)—(14) above, or to any interest rate or currency rate management activities; (D) any agreement for membership or participation in an organization that facilitates or permits the entering into or clearing of any netting agreement or any agreement described in this clause (33); (E) any agreement combining part or all of a netting agreement or part or all of any of the agreements described in this clause (33); (E) any document relating to any agreement described in this clause (33) that is filed with a Government Authority and any related service agreements; or (F) any commercial or trading agreements, each with respect to, or involving the purchase, transmission, distribution, sale, lease or hedge of, any energy, generation capacity or fuel, or any other energy related commodity or service, price or price indices for any such commodities or services or any other similar derivative agreements, and any other similar agreements (such agreements described in clauses (A) through (F) of this clause (33) being collectively, “Permitted Contracts”), Netting Agreements, Hedging Obligations and letters of credit supporting Permitted Contracts, Netting Agreements and Hedging Obligations;

(34) Liens arising under Section 9.343 of the Texas Uniform Commercial Code or similar statutes of states other than Texas;

(35) Liens created in the ordinary course of business in favor of banks and other financial institutions over credit balances of any bank accounts of the Borrower and its Subsidiaries held at such banks or financial institutions, as the case may be, to facilitate the operation of cash pooling and/or interest set-off arrangements in respect of such bank accounts in the ordinary course of business;

(36) any zoning, land use, environmental or similar law or right reserved to or vested in any Government Authority to control or regulate the use of any real property that does not materially interfere with the ordinary conduct of the business of the Borrower or any of its Restricted Subsidiaries, taken as a whole;

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(37) any Lien arising by reason of deposits with or giving of any form of security to any Government Authority for any purpose at any time as required by Applicable Laws as a condition to the transaction of any business or the exercise of any privilege or license, or to enable the Borrower or any of its Restricted Subsidiaries to maintain self-insurance or participate in any fund for liability on any insurance risks;

(38) Liens, restrictions, regulations, easements, exceptions or reservations of any Government Authority applying particularly to nuclear fuel;

(39) rights reserved to or vested in any Government Authority by the terms of any right, power, franchise, grant, license or permit, or by any provision of Applicable Law, to terminate or modify such right, power, franchise, grant, license or permit or to purchase or recapture or to designate a purchaser of any of the property of such person;

(40) Liens arising under any obligations or duties affecting any of the property of the Borrower or any of its Restricted Subsidiaries to any Government Authority with respect to any franchise, grant, license or permit which do not materially impair the use of such property for the purposes for which it is held;

(41) rights reserved to or vested in any Government Authority to use, control or regulate any property of such person;

(42) any obligations or duties, affecting the property of the Borrower or any of its Restricted Subsidiaries, to any Government Authority with respect to any franchise, grant, license or permit;

(43) a set-off or netting rights granted by the Borrower or any Subsidiary of the Borrower pursuant to any agreements related to Hedging Obligations, Netting Agreements or Permitted Contracts solely in respect of amounts owing under such agreements;

(44) Liens (i) on cash advances in favor of the seller of any property to be acquired in an Investment described under the definition of “Permitted Investments” to be applied against the purchase price for such Investment and (ii) consisting of an agreement to sell, transfer, lease or otherwise dispose of any property in a transaction excluded from the definition described under “Asset Sale,” in each case, solely to the extent such Investment or sale, disposition, transfer or lease, as the case may be, would have been permitted on the date of the creation of such Lien;

(45) rights of first refusal and purchase options in favor of Aluminum Company of America (“ Alcoa ”) to purchase Sandow Unit 4 and/or the real property related thereto, as described in (i) the Sandow Unit 4 Agreement dated August 13, 1976, as amended, between Alcoa and Texas Power & Light Company (“ TPL ”) and (ii) Deeds dated March 14, 1978 and July 21, 1980, as amended, executed by Alcoa conveying to TPL the Sandow Four real property; and

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(46) any amounts held by a trustee in the funds and accounts under any indenture securing any revenue bonds issued for the benefit of the Borrower or any of its Restricted Subsidiaries.

For purposes of this definition, the term “Indebtedness” shall be deemed to include interest on such Indebtedness.

“ Person ” shall mean any individual, corporation, limited liability company, partnership, joint venture, association, joint stock company, trust, unincorporated organization, government or any agency or political subdivision thereof or any other entity.

“ PIK Interest ” shall have the meaning provided in Section 2.8(a)(ii) .

“ PIK Interest Amount ” shall mean (i) the aggregate principal amount of all increases in outstanding principal amount of Senior Toggle Notes and issuances of PIK Notes (as defined in the Senior Refinancing Indenture) in connection with an election by the Borrower to pay interest on the Senior Toggle Notes in kind and (ii) the aggregate principal amount of all increases in outstanding principal amount of Senior Toggle Loans in connection with an election by the Borrower to pay interest on the Senior Toggle Loans in kind.

“ PIK Interest Termination Date ” shall have the meaning provided in Section 2.8(a)(ii) .

“ PIK Margin ” shall mean 0.75%  per annum .

“ Plan ” shall mean an employee pension benefit plan (other than a Multiemployer Plan) which is covered by Title IV of ERISA or subject to the minimum funding standards under Section 412 of the Code or Section 302 of ERISA and is maintained or contributed to by the Borrower, any Subsidiary or ERISA Affiliate or with respect to which the Borrower or any Subsidiary could incur liability pursuant to Title IV of ERISA.

“ Platform ” shall have the meaning provided in Section 13.17(c) .

“ Preferred Stock ” shall mean any Equity Interest with preferential rights of payment of dividends or upon liquidation, dissolution or winding up.

“ prime rate ” shall mean the “prime rate” referred to in the definition of “ABR”.

“ Pro Forma Balance Sheet ” shall have the meaning provided in Section 8.9 .

“ Pro Forma Financial Statements ” shall have the meaning set forth in Section 8.9 .

“ PUCT ” shall mean the Public Utility Commission of Texas or any successor.

“ Purchase Money Obligations ” shall mean any Indebtedness incurred to finance or refinance the acquisition, leasing, construction, repair, restoration, replacement, expansion or improvement of property (real or personal) or assets (other than Capital Stock), and whether acquired through the direct acquisition of such property or assets, or otherwise, incurred in respect of capital expenditures including Environmental CapEx Debt and Necessary CapEx Debt.

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“ Qualified Proceeds ” shall mean assets that are used or useful in, or Capital Stock of any Person engaged in, a Similar Business; provided that the fair market value of any such assets or Capital Stock shall be determined by the Borrower in good faith.

“ Rating Agencies ” shall mean Moody’s and S&P or if Moody’s or S&P or both shall not make a rating on the applicable security or other investment publicly available, a nationally recognized statistical rating agency or agencies, as the case may be, selected by the Borrower which shall be substituted for Moody’s or S&P or both, as the case may be.

“ Real Estate ” shall mean any interest in land, buildings and improvements owned, leased or otherwise held by the Borrower or any of its Restrictive Subsidiaries but excluding all operating fixtures and equipment whether or not incorporated into improvements.

“ Receivables Facility ” shall mean any of one or more receivables financing facilities as amended, supplemented, modified, extended, renewed, restated or refunded from time to time, the Obligations of which are non-recourse (except for customary representations, warranties, covenants and indemnities made in connection with such facilities) to the Borrower or any of its Restricted Subsidiaries (other than a Receivables Subsidiary) pursuant to which the Borrower or any of its Restricted Subsidiaries purports to sell its accounts receivable to either (a) a Person that is not a Restricted Subsidiary or (b) a Receivables Subsidiary that in turn funds such purchase by purporting to sell its accounts receivable to a Person that is not a Restricted Subsidiary or by borrowing from such Person or from another Receivables Subsidiary that in turn funds itself by borrowing from such Person.

“ Receivables Fees ” shall mean distributions or payments made directly or by shall mean of discounts with respect to any accounts receivable or participation interest therein issued or sold in connection with, and other fees paid to a Person that is not a Restricted Subsidiary in connection with any Receivables Facility.

“ Receivables Subsidiary ” shall mean any Subsidiary formed for the purpose of facilitating or entering into one or more Receivables Facilities, and in each case engages only in activities reasonably related or incidental thereto.

“ Refinancing ” shall have the meaning provided in the recitals to this Agreement.

“ Refinancing Indebtedness ” shall have the meaning provided in Section 9.7(b)(13).

“ Register ” shall have the meaning provided in Section 13.6(b)(iv) .

“ Regulation T ” shall mean Regulation T of the Board as from time to time in effect and any successor to all or a portion thereof establishing margin requirements.

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“ Regulation U ” shall mean Regulation U of the Board as from time to time in effect and any successor to all or a portion thereof establishing margin requirements.

“ Regulation X ” shall mean Regulation X of the Board as from time to time in effect and any successor to all or a portion thereof establishing margin requirements.

“ Related Business Assets ” shall mean assets (other than cash or Cash Equivalents) used or useful in a Similar Business; provided that any assets received by the Borrower or a Restricted Subsidiary in exchange for assets transferred by the Borrower or a Restricted Subsidiary will not be deemed to be Related Business Assets if they consist of securities of a Person, unless upon receipt of the securities of such Person, such Person would become a Restricted Subsidiary.

“ Related Parties ” shall mean, with respect to any specified Person, such Person’s Affiliates and the directors, officers, employees, agents, trustees and advisors of such Person and any Person that possesses, directly or indirectly, the power to direct or cause the direction of the management or policies of such Person, whether through the ability to exercise voting power, by contract or otherwise.

“ Repaid Indebtedness ” shall mean:

“ Reportable Event ” shall mean an event described in Section 4043 of ERISA and the regulations thereunder, other than any event as to which the thirty day notice period has been waived.

“ Required Lenders ” shall mean, at any date, Non-Defaulting Lenders having or holding a majority of (i) the Loans (excluding the Loans of Defaulting Lenders) in the aggregate at such date, or (ii) after issuance of any Senior Notes, a majority of the outstanding principal amount of the Loans (excluding the Loans of Defaulting Lenders) and the Senior Notes in the aggregate at such date, voting as a single class.

“ Restoration Certificate ” shall mean, with respect to any Casualty Event, an Officer’s Certificate provided to the Administrative Agent prior to the 365 ^th day after such Casualty Event has occurred certifying (a) that the Borrower or such Restricted Subsidiary intends to use the proceeds received in connection with such Casualty Event to repair, restore or replace the property or assets in respect of which such Casualty Event occurred, (b) the approximate costs of completion of such repair, restoration or replacement and (c) that such repair, restoration or replacement will be completed within the later of (x) 450 days after the date on which cash proceeds with respect to such Casualty Event were received and (y) 180 days after delivery of such Restoration Certificate.

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“ Restricted Investment ” shall mean an Investment other than a Permitted Investment.

“ Restricted Payment Coverage Ratio ” shall mean (i) for Restricted Payments (other than payments of cash dividends or distributions on, or in respect of, the Borrower’s Capital Stock, purchases for cash or other acquisitions for cash of any Capital Stock of the Borrower or any direct or indirect parent of the Borrower for the purpose of paying any such dividend or distribution to, or acquisitions of Capital Stock of any direct or indirect parent of the Borrower for cash from, the Investors, or guaranteeing any Indebtedness of any Affiliate of the Borrower for the purpose of paying such dividend, making such distribution or so acquiring such Capital Stock to or from the Investors, all such Restricted Payments being referred to as “ Investor Payments ”), the Fixed Charge Coverage Ratio of the Borrower and its Restricted Subsidiaries treating the Oncor Subsidiaries as Restricted Subsidiaries for purposes of such calculation and (ii) for Restricted Payments constituting Investor Payments, the Fixed Charge Coverage Ratio of the Borrower and its Restricted Subsidiaries.

“ Restricted Subsidiary ” shall mean, at any time, any direct or indirect Subsidiary of the Borrower (including any Foreign Subsidiary) that is not then an Unrestricted Subsidiary; provided , however , that upon an Unrestricted Subsidiary’s ceasing to be an Unrestricted Subsidiary, such Subsidiary shall be included in the definition of “Restricted Subsidiary.”

“ S&P ” shall mean Standard & Poor’s, a division of The McGraw-Hill Companies, Inc., and any successor to its rating agency business.

“ Sale and Lease-Back Transaction ” shall mean any arrangement providing for the leasing by the Borrower or any of its Restricted Subsidiaries of any real or tangible personal property, which property has been or is to be sold or transferred by the Borrower or such Restricted Subsidiary to a third Person in contemplation of such leasing.

“ SEC ” shall mean the Securities and Exchange Commission.

“ Section 9.1 Financials ” shall mean the financial statements delivered, or required to be delivered, pursuant to Section 9.1(a)(i) or (ii) .

“ Secured Indebtedness ” shall mean any Indebtedness of the Borrower or any of its Restricted Subsidiaries secured by a Lien.

“ Securities Act ” shall mean the Securities Act of 1933, as amended, and the rules and regulations of the SEC promulgated thereunder.

“ Securitization ” shall mean a public or private offering by a Lender or any of its Affiliates or their respective successors and assigns of securities or notes which represent an interest in, or which are collateralized, in whole or in part, by the Loans and the Lender’s rights under the Credit Documents.

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“ Senior Cash Pay Fixed Rate ” shall mean 11.00%  per annum .

“ Senior Cash Pay Loans ” shall mean Senior Interim Cash Pay Loans and/or Senior Cash Pay Term Loans, as the context requires.

“ Senior Cash Pay Notes ” shall mean senior notes due 2017, to be issued in connection with the refinancing of the Senior Interim Cash Pay Loans or the exchange of the Senior Cash Pay Term Loans under the Senior Refinancing Indenture, in an aggregate principal amount of up to $2,000,000,000 (less the amount of any Senior Interim Cash Pay Loans and Senior Cash Pay Term Loans that remain outstanding after the issuance of the Senior Cash Pay Notes), together with interest, fees and all other amounts payable in connection therewith.

“ Senior Cash Pay Term Loans ” shall have the meaning provided in Section 2.14(a)(i) .

“ Senior Indebtedness ” shall mean:

(1) all Indebtedness of the Borrower or any Guarantor outstanding under this Agreement and each related Guarantee, the Senior Notes and each related guarantee thereof, the TCEH Senior Secured Facilities and each related guarantee, the TCEH Senior Notes and related guarantees (including interest accruing on or after the filing of any petition in bankruptcy or similar proceeding or for reorganization of the Borrower or any Guarantor (at the rate provided for in the documentation with respect thereto, regardless of whether or not a claim for post-filing interest is allowed in such proceedings)), and any and all other fees, expense reimbursement obligations, indemnification amounts, penalties, and other amounts (whether existing on the Closing Date or thereafter created or incurred) and all obligations of the Borrower or any Guarantor to reimburse any bank or other Person in respect of amounts paid under letters of credit, acceptances or other similar instruments;

(2) all Hedging Obligations (and guarantees thereof) owing to a Lender (as defined in the TCEH Senior Secured Facilities) or any Affiliate of such Lender (or any Person that was a Lender or an Affiliate of such Lender at the time the applicable agreement giving rise to such Hedging Obligation was entered into); provided that such Hedging Obligations are permitted to be incurred under the terms of this Agreement;

(3) any other Indebtedness of the Borrower or any Guarantor permitted to be incurred under the terms of this Agreement, unless the instrument under which such Indebtedness is incurred expressly provides that it is subordinated in right of payment to the Indebtedness outstanding under the Loans or any related Guarantee; and

(4) all Obligations with respect to the items listed in the preceding clauses (1), (2) and (3);

provided , however , that Senior Indebtedness shall not include:

(a) any obligation of such Person to the Borrower or any of its Subsidiaries;

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(b) any liability for federal, state, local or other taxes owed or owing by such Person;

(c) any accounts payable or other liability to trade creditors arising in the ordinary course of business;

(d) any Indebtedness or other Obligation of such Person which is subordinate or junior in any respect to any other Indebtedness or other Obligation of such Person; or

(e) that portion of any Indebtedness which at the time of incurrence is incurred in violation of this Agreement;

(f) US Holdings’ Floating Rate Junior Subordinated Debentures, Series D due 2037; or

(g) US Holdings’ 8.175% Fixed Junior Subordinated Debentures, Series E due 2037.

“ Senior Interim Cash Pay Loan ” shall have the meaning provided in Section 2.1(a)(i) .

“ Senior Interim Cash Pay Loan Commitment ” shall mean (a) in the case of each Lender that is a Lender on the date hereof, the amount set forth opposite such Lender’s name on Schedule 1.1(a)  as such Lender’s “Senior Interim Cash Pay Loan Commitment” and (b) in the case of any Lender that becomes a Lender after the date hereof, the amount specified as such Lender’s “Senior Interim Cash Pay Loan Commitment” in the Assignment and Acceptance pursuant to which such Lender assumed a portion of the Total Senior Interim Loan Commitment, in each case as the same may be changed from time to time pursuant to the terms hereof. The aggregate amount of the Senior Interim Cash Pay Loan Commitments as of the Closing Date is $2,000,000,000.

“ Senior Interim Cash Pay Loans Requested Amount ” shall have the meaning provided in Section 2.3(a) .

“ Senior Interim Loan Commitment ” shall mean, with respect to each Lender, such Lender’s Senior Interim Cash Pay Loan Commitment and Senior Interim Toggle Loan Commitment.

“ Senior Interim Loans ” shall mean the Senior Interim Cash Pay Loans and/or Senior Interim Toggle Loans, as the context requires.

“ Senior Interim Toggle Loan ” shall have the meaning provided in Section 2.1(a)(ii) .

“ Senior Interim Toggle Loan Commitment ” shall mean (a) in the case of each Lender that is a Lender on the date hereof, the amount set forth opposite such Lender’s name on Schedule 1.1(a)  as such Lender’s “Senior Interim Toggle Loan Commitment” and (b) in the case of any Lender that becomes a Lender after the date hereof, the amount specified as such Lender’s

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“Senior Interim Toggle Loan Commitment” in the Assignment and Acceptance pursuant to which such Lender assumed a portion of the Total Senior Interim Loan Commitment, in each case as the same may be changed from time to time pursuant to the terms hereof. The aggregate amount of the Senior Interim Toggle Loan Commitments as of the Closing Date is $2,500,000,000.

“ Senior Interim Toggle Loans Requested Amount ” shall have the meaning provided in Section 2.3(a) .

“ Senior Notes ” shall mean Senior Cash Pay Notes and/or Senior Toggle Notes, as the context requires.

“ Senior Refinancing Indenture ” shall mean the indenture substantially in the form attached as Exhibit C to be entered into in connection with the exchange of the Senior Term Loans, among the Borrower, the Guarantors and a trustee, pursuant to which the Senior Notes shall be issued.

“ Senior Refinancing Registration Rights Agreement ” shall mean the registration rights agreement substantially in the form attached as Exhibit D to be entered into in connection with the exchange of the Senior Term Loans, among the Borrower, the Guarantors and the Administrative Agent, relating to rights given by the Borrower and the Guarantors to the holders of Senior Notes to register such notes under the Securities Act.

“ Senior Secured Credit Agreement ” shall have the meaning provided in the recitals to this Agreement.

“ Senior Secured Delayed Draw Term Loans ” shall have the meaning provided in the recitals to this Agreement.

“ Senior Secured Deposit L/C Loans ” shall have the meaning provided in the recitals to this Agreement.

“ Senior Secured Initial Term Loans ” shall have the meaning provided in the recitals to this Agreement.

“ Senior Secured Revolving Credit Loans ” shall have the meaning provided in the recitals to this Agreement.

“ Senior Term Loans ” shall mean Senior Cash Pay Term Loans and/or Senior Toggle Term Loans, as the context requires.

“ Senior Toggle Fixed Rate ” shall mean 11.25%  per annum .

“ Senior Toggle Loans ” shall mean Senior Interim Toggle Loans and/or Senior Toggle Term Loans, as the context requires.

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“ Senior Toggle Notes ” shall mean (a) senior toggle notes due 2017, to be issued in connection with the refinancing of the Senior Interim Toggle Loans or the exchange of the Senior Toggle Term Loans under the Senior Refinancing Indenture, in an aggregate principal amount of up to $2,500,000,000 (less the amount of any Senior Interim Toggle Loans and Senior Toggle Term Loans that remain outstanding after the issuance of the Senior Toggle Notes), together with interest (including any PIK Interest), fees and all other amounts payable in connection therewith.

“ Senior Toggle Term Loans ” shall have the meaning provided in Section 2.14(a)(ii) .

“ Shell Wind ” shall mean a joint venture with Shell WindEnergy Inc. (or similar entity) in which the Borrower and its Restricted Subsidiaries have up to a 50% ownership interest relating to the joint development of a 3,000 megawatt wind project in Texas and other renewable energy projects in Texas.

“ Significant Subsidiary ” shall mean any Restricted Subsidiary that would be a “significant subsidiary” as defined in Article 1, Rule 1-02 of Regulation S-X, promulgated pursuant to the Securities Act, as such regulation is in effect on the Closing Date.

“ Similar Business ” shall mean any business conducted or proposed to be conducted by the Borrower and its Subsidiaries on the Closing Date or any business that is similar, reasonably related, incidental or ancillary thereto.

“ Solvent ” shall mean, with respect to any Person, that as of the Closing Date, (a) (i) the sum of such Person’s debt (including contingent liabilities) does not exceed the present fair saleable value of such Person’s present assets; (ii) such Person’s capital is not unreasonably small in relation to its business as contemplated on the Closing Date; and (iii) such Person has not incurred and does not intend to incur, or believe that it will incur, debts including current obligations beyond its ability to pay such debts as they become due (whether at maturity or otherwise); and (b) such Person is “solvent” within the meaning given that term and similar terms under Applicable Laws relating to fraudulent transfers and conveyances. For purposes of this definition, the amount of any contingent liability at any time shall be computed as the amount that, in light of all of the facts and circumstances existing at such time, represents the amount that can reasonably be expected to become an actual or matured liability (irrespective of whether such contingent liabilities meet the criteria for accrual under Statement of Financial Accounting Standard No. 5).

“ Sponsors ” shall mean any of KKR, TPG, J.P. Morgan Ventures Corporation, Citigroup Global Markets Inc., Morgan Stanley & Co. Incorporated, Goldman Sachs & Co., and LB I Group and each of their respective Affiliates, but not including, however, any portfolio companies of any of the foregoing.

“ Sponsor Management Agreement ” shall mean the management agreement between certain of the management companies associated with the Sponsors and the Borrower.

“ SPV ” shall have the meaning provided in Section 13.6(g) .

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“ Stock ” shall mean shares of capital stock or shares in the capital, as the case may be (whether denominated as common stock or preferred stock or ordinary shares or preferred shares, as the case may be), beneficial, partnership or membership interests, participations or other equivalents (regardless of how designated) of or in a corporation, partnership, limited liability company or equivalent entity, whether voting or non-voting.

“ Stock Equivalents ” shall mean all securities convertible into or exchangeable for Stock and all warrants, options or other rights to purchase or subscribe for any Stock, whether or not presently convertible, exchangeable or exercisable.

“ Subordinated Indebtedness ” shall mean,

(1) any Indebtedness of the Borrower which is by its terms subordinated in right of payment to the Loans, and

(2) any Indebtedness of any Guarantor which is by its terms subordinated in right of payment to the Guarantee of such entity of the Loans.

“ Subsidiary ” shall mean, with respect to any Person:

(1) any corporation, association, or other business entity (other than a partnership, joint venture, limited liability company or similar entity) of which more than 50% of the total voting power of shares of Capital Stock entitled (without regard to the occurrence of any contingency) to vote in the election of directors, managers or trustees thereof is at the time of determination owned or controlled, directly or indirectly, by such Person or one or more of the other Subsidiaries of that Person or a combination thereof; and

(2) any partnership, joint venture, limited liability company or similar entity of which

(x) more than 50% of the capital accounts, distribution rights, total equity and voting interests or general or limited partnership interests, as applicable, are owned or controlled, directly or indirectly, by such Person or one or more of the other Subsidiaries of that Person or a combination thereof whether in the form of membership, general, special or limited partnership or otherwise, and

(y) such Person or any Restricted Subsidiary of such Person is a controlling general partner or otherwise controls such entity.

Unless otherwise expressly provided, all references herein to a “Subsidiary” shall mean a Subsidiary of the Borrower.

“ Syndication Agent ” shall mean Goldman Sachs Credit Partners L.P., together with its Affiliates, as syndication agent for the Lenders under this Agreement and the other Loan Documents.

“ Taxes ” shall mean any and all present or future taxes, duties, levies, imposts, assessments, deductions, withholdings or other similar charges imposed by any Government Authority whether computed on a separate, consolidated, unitary, combined or other basis and any interest, fines, penalties or additions to tax with respect to the foregoing.

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“ TCEH ” shall mean Texas Competitive Electric Holdings Company LLC, a Delaware limited liability company.

“ TCEH PIK Notes ” shall have the meaning assigned to the term “PIK Notes” in the senior refinancing indenture in respect of the TCEH Senior Notes.

“ TCEH Senior Cash Pay Notes ” shall mean senior notes due 2015, to be issued by TCEH in connection with the refinancing of the TCEH Senior Interim Cash Pay Loans or the exchange of TCEH’s senior cash pay term loans under the senior refinancing indenture referred to in the TCEH Senior Unsecured Interim Loan Agreement, in an aggregate principal amount of up to $5,000,000,000 (less the amount of any TCEH Senior Interim Cash Pay Loans and senior cash pay term loans of TCEH under the TCEH Senior Unsecured Interim Loan Agreement that remain outstanding after the issuance of the TCEH Senior Cash Pay Notes), together with interest, fees and all other amounts payable in connection therewith.

“ TCEH Senior Interim Cash Pay Loans ” shall have the meaning provided in the recitals to this Agreement.

“ TCEH Senior Interim Facilities ” shall mean the TCEH Senior Unsecured Interim Loan Agreement, including any guarantees, instruments and agreements executed in connection therewith, and any amendments, supplements, modifications or restatements thereof.

“ TCEH Senior Interim Loans ” shall mean the TCEH Senior Interim Loans defined in the recitals to this Agreement.

“ TCEH Senior Interim Toggle Loans ” shall have the meaning provided in the recitals to this Agreement.

“ TCEH Senior Notes ” shall mean the TCEH Senior Cash Pay Notes and the TCEH Senior Toggle Notes.

“ TCEH Senior Secured Facilities ” shall mean the TCEH Senior Secured Credit Agreement, including any guarantees, collateral documents, instruments and agreements executed in connection therewith, and any amendments, supplements, modifications, extensions, renewals, restatements, refundings or refinancings thereof and any indentures or credit facilities or commercial paper facilities with banks or other institutional lenders or investors that replace, refund or refinance any part of the loans, notes, other credit facilities or commitments thereunder, including any such replacement, refunding or refinancing facility or indenture that increases the amount borrowable thereunder or alters the maturity thereof ( provided that such increase in borrowings is permitted under Section 9.7 ).

“ TCEH Senior Toggle Notes ” shall mean senior toggle notes due 2016, to be issued by TCEH in connection with the refinancing of the TCEH Senior Interim Toggle Loans or the exchange of the TCEH’s senior toggle term loans under the senior refinancing indenture referred to in the TCEH Senior Unsecured Interim Loan Agreement, in an aggregate principal amount of up to $1,750,000,000 (less the amount of any TCEH Senior Interim Toggle Loans and TCEH Senior Toggle Term Loans that remain outstanding after the issuance of the TCEH Senior Toggle Notes), together with interest (including any PIK interest), fees and all other amounts payable in connection therewith.

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“ TCEH Senior Unsecured Interim Loan Agreement ” shall have the meaning provided in the recitals to this Agreement.

“ Term Loan Maturity Date ” shall have the meaning provided such term in the definition of “ Maturity Date. ”

“ Test Period ” shall mean, for any determination under this Agreement, the four consecutive fiscal quarters of the Borrower then last ended and for which Section 9.1 Financials have been or were required to have been delivered.

“ Total Assets ” shall mean the total assets of the Borrower and its Restricted Subsidiaries on a consolidated basis, as shown on the most recent consolidated balance sheet of the Borrower or such other Person as may be expressly stated.

“ Total Credit Exposure ” shall mean, at any date, the aggregate outstanding principal amount of all Loans at such date.

“ Total Senior Interim Loan Commitment ” shall mean the sum of Senior Interim Cash Pay Loan Commitments and Senior Interim Toggle Loan Commitments of all Lenders.

“ TPG ” shall mean TPG Capital, L.P.

“ Transactions ” shall mean, collectively, the transactions contemplated by this Agreement (including the entering into and funding hereunder), the TCEH Senior Secured Facilities, the TCEH Senior Unsecured Interim Loan Agreement, the Oncor Electric Delivery Facility, the Receivables Facility entered into on the Closing Date, the Merger and the Equity Contribution, the Refinancing, the payment of fees and expenses in connection therewith and the consummation of any other transaction connected with the foregoing.

“ Transferee ” shall have the meaning provided in Section 13.6(e) .

“ Trustee ” shall have the meaning provided in Section 2.14(b)(iv) .

“ Type ” shall mean as to any Loan, its nature as an ABR Loan or a LIBOR Loan.

“ Unfunded Current Liability ” of any Plan shall mean the amount, if any, by which the Accumulated Benefit Obligation (as defined under Statement of Financial Accounting Standards No. 87 (“ SFAS 87 ”)) under the Plan as of the close of its most recent plan year, determined in accordance with SFAS 87 as in effect on the date hereof, exceeds the fair market value of the assets allocable thereto.

“ Unit ” shall mean an individual power plant generation system comprised of all necessary physically connected generators, reactors, boilers, combustion turbines and other prime movers operated together to independently generate electricity.

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“ Unrestricted Cash ” shall mean, as of any date, without duplication, (a) all cash and Cash Equivalents (in each case, free and clear of all Liens, other than nonconsensual Liens permitted by Section 9.10 and Liens permitted by clause (23) , subclauses (i) and (ii)  of clause (26)  and clause (33)  of the definition of “Permitted Liens”, included in the cash and cash equivalents accounts listed on the consolidated balance sheet of the Borrower and its Restricted Subsidiaries as of such date and (b) all unrestricted margin deposits related to commodity positions listed on the consolidated balance sheet of Borrower and the Restricted Subsidiaries

“ Unrestricted Subsidiary ” shall mean:

(1) each of the Oncor Subsidiaries;

(2) any Subsidiary of the Borrower which at the time of determination is an Unrestricted Subsidiary (as designated by the Borrower, as provided below); and

(3) any Subsidiary of an Unrestricted Subsidiary.

The Borrower may designate any Subsidiary of the Borrower (including any existing Subsidiary and any newly acquired or newly formed Subsidiary) to be an Unrestricted Subsidiary unless such Subsidiary or any of its Subsidiaries owns any Equity Interests or Indebtedness of, or owns or holds any Lien on, any property of, the Borrower or any Subsidiary of the Borrower (other than solely any Subsidiary of the Subsidiary to be so designated); provided that

(1) any Unrestricted Subsidiary must be an entity of which the Equity Interests entitled to cast at least a majority of the votes that may be cast by all Equity Interests having ordinary voting power for the election of directors or Persons performing a similar function are owned, directly or indirectly, by the Borrower;

(2) such designation complies with Section 9.5 hereof; and

(3) each of:

(a) the Subsidiary to be so designated; and

(b) its Subsidiaries

has not at the time of designation, and does not thereafter, create, incur, issue, assume, guarantee or otherwise become directly or indirectly liable with respect to any Indebtedness pursuant to which the lender has recourse to any of the assets of the Borrower or any Restricted Subsidiary.

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The Borrower may designate any Unrestricted Subsidiary to be a Restricted Subsidiary; provided that, immediately after giving effect to such designation, no Default shall have occurred and be continuing and either:

(1) in the case of any Subsidiary of the Borrower other than TCEH and any of its Subsidiaries, (A) the Borrower would be permitted to incur at least $1.00 of additional Indebtedness pursuant to clause (i)  of Section 9.7(a) hereof; or (B) the Fixed Charge Coverage Ratio for the Borrower and its Restricted Subsidiaries would be greater than such ratio for the Borrower and its Restricted Subsidiaries immediately prior to such designation, in each case on a pro forma basis taking into account such designation; or

(2) in the case of TCEH and any of its Subsidiaries, (A) TCEH would be permitted to Incur at least $1.00 of additional Indebtedness pursuant to clause (ii)  of such Fixed Charge Coverage Ratio test or (B) such Fixed Charge Coverage Ratio for TCEH and its Restricted Subsidiaries would be greater than such ratio for TCEH and its Restricted Subsidiaries immediately prior to such designation, in each case on a pro forma basis taking into account such designation.

Any such designation by the Borrower shall be notified by the Borrower to the Administrative Agent by promptly filing with the Administrative Agent a copy of the resolution of the Board of Directors of the Borrower or any committee thereof giving effect to such designation and an Officer’s Certificate certifying that such designation complied with the foregoing provisions.

“ U.S. ” or “ United States ” shall mean the United States of America.

“ US Holdings ” shall mean Energy Future Competitive Holdings Company, a Texas corporation.

“ U.S. Lender ” shall have the meaning provided in Section 5.4(h) .

“ Voting Stock ” of any Person as of any date shall mean the Capital Stock of such Person that is at the time entitled to vote in the election of the Board of Directors of such Person.

“ Weighted Average Life to Maturity ” shall mean, when applied to any Indebtedness, Disqualified Stock or Preferred Stock, as the case may be, at any date, the quotient obtained by dividing:

(1) the sum of the products of the number of years from the date of determination to the date of each successive scheduled principal payment of such Indebtedness or redemption or similar payment with respect to such Disqualified Stock or Preferred Stock multiplied by the amount of such payment; by

(2) the sum of all such payments.

“ Wholly Owned Subsidiary ” of any Person shall mean a Subsidiary of such Person, 100% of the outstanding Equity Interests of which (other than directors’ qualifying shares) shall at the time be owned by such Person or by one or more Wholly-Owned Subsidiaries of such Person.

1.2. Other Interpretive Provisions . With reference to this Agreement and each other Loan Document, unless otherwise specified herein or in such other Loan Document:

(a) The meanings of defined terms are equally applicable to the singular and plural forms of the defined terms.

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(b) The words “herein”, “hereto”, “hereof” and “hereunder” and words of similar import when used in any Loan Document shall refer to such Loan Document as a whole and not to any particular provision thereof.

(c) Article, Section, Exhibit and Schedule references are to the Loan Document in which such reference appears.

(d) The term “including” is by way of example and not limitation.

(e) The term “documents” includes any and all instruments, documents, agreements, certificates, notices, reports, financial statements and other writings, however evidenced, whether in physical or electronic form.

(f) In the computation of periods of time from a specified date to a later specified date, the word “from” shall mean “from and including”; the words “to” and “until” each shall mean “to but excluding”; and the word “through” shall mean “to and including”.

(g) Section headings herein and in the other Loan Documents are included for convenience of reference only and shall not affect the interpretation of this Agreement or any other Loan Document.

(h) To the extent any provision of the Senior Refinancing Indenture is deemed to be incorporated and set forth in this Agreement, (i) any reference to the “Issuer” or the “Company” in the Senior Refinancing Indenture shall be deemed to be a reference to the Borrower, (ii) any reference to a “Holder” in the Senior Refinancing Indenture shall be deemed to be a reference to a Lender, (iii) any reference to the “Trustee” in the Senior Refinancing Indenture shall be deemed to be a reference to the Administrative Agent, (iv) any reference to the “Notes” in the Senior Refinancing Indenture shall be deemed to be a reference to the Loans and (v) any reference to “this Indenture” in the Senior Refinancing Indenture shall be deemed to be a reference to this Agreement and the other Loan Documents, in each case as the context may require.

1.3. Accounting Terms . All accounting terms not specifically or completely defined herein shall be construed in conformity with, and all financial data (including financial ratios and other financial calculations) required to be submitted pursuant to this Agreement shall be prepared in conformity with, GAAP.

1.4. [Reserved ] .

1.5. References to Agreements, Laws, Etc . Unless otherwise expressly provided herein, (a) references to organizational documents, agreements (including the Loan Documents) and other Contractual Requirements shall be deemed to include all subsequent amendments, restatements, amendment and restatements, extensions, supplements and other modifications thereto, but only to the extent that such amendments, restatements, amendment and restatements, extensions, supplements and other modifications are permitted by any Loan Document; and (b) references to any Applicable Laws shall include al