Document:

<PAGE>   1
                                                                     EXHIBIT 4.1

                                                                  EXECUTION COPY
                                                                  --------------

                          NRG NORTHEAST GENERATING LLC,

                           the GUARANTORS party hereto

                                       and

                            THE CHASE MANHATTAN BANK

                                   as Trustee

                                    INDENTURE

                          Dated as of February 22, 2000

                               -----------------

                              Senior Secured Bonds

                                ----------------

<PAGE>   2

                                TABLE OF CONTENTS
<TABLE>
<CAPTION>
                                                                                       Page
                                                                                       ----
<S>                                                                                    <C>
ARTICLE 1  DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION.....................    1
     SECTION 1.1  Definitions; Construction............................................    1
     SECTION 1.2  Compliance Certificates and Opinions.................................   23
     SECTION 1.3  Form of Documents Delivered to Trustee...............................   24
     SECTION 1.4  Notices, Etc. to Trustee.............................................   24
     SECTION 1.5  Notices to Holders; Waiver...........................................   25
     SECTION 1.6  Conflict with Trust Indenture Act....................................   25
     SECTION 1.7  Effect of Headings and Table of Contents.............................   26
     SECTION 1.8  Successors and Assigns...............................................   26
     SECTION 1.9  Severability Clause..................................................   26
     SECTION 1.10  Benefits of Indenture...............................................   26
     SECTION 1.11  Governing Law.......................................................   26
     SECTION 1.12  Legal Holidays......................................................   26
     SECTION 1.13  Execution in Counterparts...........................................   26

ARTICLE 2  THE BONDS...................................................................   27
     SECTION 2.1  Form of Bond to Be Established by Series Supplemental
                    Indenture..........................................................   27
     SECTION 2.2  Form of Trustee's Authentication.....................................   27
     SECTION 2.3  Amount; Issuable in Series...........................................   27
     SECTION 2.4  Authentication and Delivery of Bonds.................................   28
     SECTION 2.5  Form.................................................................   29
     SECTION 2.6  Execution of Bonds...................................................   30
     SECTION 2.7  Temporary Bonds......................................................   30
     SECTION 2.8  Registration; Restrictions on Transfer and Exchange..................   31
     SECTION 2.9  Mutilated, Destroyed, Lost and Stolen Bonds..........................   32
     SECTION 2.10  Payment of Principal and Interest; Principal and Interest Rights
                    Preserved..........................................................   33
     SECTION 2.11  Persons Deemed Owners...............................................   34
     SECTION 2.12  Cancellation........................................................   35
     SECTION 2.13  Dating of Bonds; Computation of Interest............................   35
     SECTION 2.14  Source of Payments Limited; Rights and Liabilities of the Issuer....   35
     SECTION 2.15  Allocation of Principal and Interest................................   35
     SECTION 2.16  Parity of Bonds.....................................................   35

ARTICLE 3  APPLICATION OF PROCEEDS FROM SALE OF BONDS..................................   36
     SECTION 3.1  Application of Proceeds from Sale of Bonds...........................   36

ARTICLE 4  DEBT SERVICE RESERVE ACCOUNT................................................   36
     SECTION 4.1  Debt Service Reserve Account.........................................   36
     SECTION 4.2.  Securities Account; Securities Intermediary.........................   39
</TABLE>

                                      -i-
<PAGE>   3

<TABLE>
<S>                                                                                     <C>
     SECTION 4.3.  Security Interest...................................................   40
     SECTION 4.4  Investment of Funds..................................................   41

ARTICLE 5  THE GUARANTEES..............................................................   41
     SECTION 5.1  The Guarantees.......................................................   41
     SECTION 5.2  Obligations Unconditional............................................   42
     SECTION 5.3  Reinstatement........................................................   42
     SECTION 5.4  Subrogation..........................................................   43
     SECTION 5.5  Remedies.............................................................   43
     SECTION 5.6  Instrument for the Payment of Money..................................   43
     SECTION 5.7  Continuing Guarantees................................................   43
     SECTION 5.8  Rights of Contribution...............................................   43
     SECTION 5.9  General Limitation on Guarantee Obligations..........................   44
     SECTION 5.10  Effectiveness.......................................................   44

ARTICLE 6  COVENANTS OF THE ISSUER.....................................................   45
     SECTION 6.1  Financial Statements and Other Information...........................   45
     SECTION 6.2  Existence; Conduct of Business.......................................   46
     SECTION 6.3  Maintenance of Tax Status............................................   46
     SECTION 6.4  Compliance with Laws and Contractual Obligations.....................   46
     SECTION 6.5  Maintenance of Properties; Insurance.................................   46
     SECTION 6.6  Payment of Taxes and Claims..........................................   47
     SECTION 6.7  Books and Records; Inspection Rights.................................   47
     SECTION 6.8  Indebtedness.........................................................   47
     SECTION 6.9  Liens................................................................   48
     SECTION 6.10  Certain Obligations Respecting Subsidiaries.........................   48
     SECTION 6.11  Restrictive Agreements..............................................   48
     SECTION 6.12  Prohibition on Sale of Assets.......................................   49
     SECTION 6.13  Modifications of Certain Documents..................................   49
     SECTION 6.14  Prohibition on Fundamental Changes..................................   49
     SECTION 6.15  Restricted Payments.................................................   50
     SECTION 6.16  Transactions with Affiliates........................................   50
     SECTION 6.17  Investments.........................................................   51
     SECTION 6.18  EWG Status..........................................................   52
     SECTION 6.19  Debt Service Reserve Account........................................   52
     SECTION 6.20  Rule 144A Information...............................................   52

ARTICLE 7  COVENANTS OF THE GUARANTORS.................................................   53
     SECTION 7.1  Existence; Conduct of Business.......................................   53
     SECTION 7.2  Compliance with Laws and Contractual Obligations.....................   53
     SECTION 7.3  Maintenance of Properties; Insurance.................................   53
     SECTION 7.4  Indebtedness.........................................................   53
     SECTION 7.5  Liens................................................................   53
     SECTION 7.6  Prohibition on Fundamental Changes...................................   54
     SECTION 7.7  Restricted Payments..................................................   54
     SECTION 7.8  Transactions with Affiliates.........................................   54
     SECTION 7.9  Investments..........................................................   55
     SECTION 7.10  Operation of Facilities.............................................   56
</TABLE>
                                     -ii-

<PAGE>   4

<TABLE>
<S>                                                                                      <C>
     SECTION 7.11  Prohibition on Sale of Assets.......................................   56
     SECTION 7.12  Modification of Certain Documents...................................   56

ARTICLE 8  REDEMPTION OF BONDS.........................................................   56
     SECTION 8.1  Optional Redemption; Redemption Price................................   56
     SECTION 8.2  Election or Requirement to Redeem; Notice to Trustee.................   56
     SECTION 8.3  Mandatory Redemption; Selection of Bonds to Be Redeemed;
                   Redemption Price....................................................   57
     SECTION 8.4  Notice of Redemption.................................................   58
     SECTION 8.5  Bonds Payable on Redemption Date.....................................   59
     SECTION 8.6  Bonds Redeemed in Part...............................................   59

ARTICLE 9  REPURCHASE UPON CHANGE OF CONTROL...........................................   59
     SECTION 9.1.  Change of Control...................................................   59

ARTICLE 10  EVENTS OF DEFAULT AND REMEDIES.............................................   60
     SECTION 10.1  Events of Default...................................................   60
     SECTION 10.2  Acceleration of Maturity; Rescission and Annulment..................   62
     SECTION 10.3  Trustee May File Proofs of Claim; Appointment of Trustee as
                   Attorney-in-Fact in Judicial Proceedings............................   63
     SECTION 10.4  Trustee May Enforce Claims Without Possession of Bonds..............   64
     SECTION 10.5  Application of Money Collected......................................   64
     SECTION 10.6  Limitation on Suits.................................................   64
     SECTION 10.7  Unconditional Right of Holders to Receive Principal, Premium
                   and Interest........................................................   65
     SECTION 10.8  Restoration of Rights and Remedies..................................   65
     SECTION 10.9  Rights and Remedies Cumulative......................................   65
     SECTION 10.10  Delay or Omission Not Waiver.......................................   65
     SECTION 10.11  Control by Holders.................................................   66
     SECTION 10.12  Waiver of Past Defaults............................................   66
     SECTION 10.13  Undertaking for Costs..............................................   66
     SECTION 10.14  Waiver of Stay or Extension Laws...................................   67

ARTICLE 11  CONCERNING THE TRUSTEE.....................................................   67
     SECTION 11.1  Certain Rights and Duties of Trustee................................   67
     SECTION 11.2  Trustee Not Responsible for Recitals, Etc...........................   69
     SECTION 11.3  Trustee and Others May Hold Bonds...................................   69
     SECTION 11.4  Moneys Held by Trustee or Paying Agent..............................   69
     SECTION 11.5 Compensation of Trustee and Its Lien.................................   69
     SECTION 11.6  Right of Trustee to Rely on Officer's Certificates and Opinions
                   of Counsel..........................................................   70
     SECTION 11.7  Persons Eligible for Appointment As Trustee.........................   70
     SECTION 11.8  Resignation and Removal of Trustee; Appointment of Successor........   71
     SECTION 11.9  Acceptance of Appointment by Successor Trustee......................   72
     SECTION 11.10  Merger, Conversion or Consolidation of Trustee.....................   73
     SECTION 11.11  Maintenance of Offices and Agencies................................   73
     SECTION 11.12  Reports by Trustee.................................................   75
     SECTION 11.13  Trustee Risk.......................................................   76
</TABLE>

                                     -iii-

<PAGE>   5

<TABLE>
<S>                                                                                     <C>
     SECTION 11.14  Appointment of Co-Trustee..........................................   76
     SECTION 11.15  Knowledge of Default...............................................   76

ARTICLE 12  CONCERNING THE HOLDERS.....................................................   77
     SECTION 12.1  Acts of Holders.....................................................   77
     SECTION 12.2  Bonds Owned by Issuer and Affiliates Deemed Not Outstanding.........   78

ARTICLE 13  HOLDERS' MEETINGS..........................................................   78
     SECTION 13.1  Purposes for Which Holders' Meetings May Be Called..................   78
     SECTION 13.2  Issuer and Holders May Call Meeting.................................   79
     SECTION 13.3  Persons Entitled to Vote at Meeting.................................   79
     SECTION 13.4  Determination of Voting Rights; Conduct and Adjournment of
                   Meeting.............................................................   79
     SECTION 13.5  Counting Votes and Recording Action of Meeting......................   80

ARTICLE 14  SUPPLEMENTAL INDENTURES....................................................   80
     SECTION 14.1 Supplemental Indentures Without Consent of Holders...................   80
     SECTION 14.2  Supplemental Indenture with Consent of Holders......................   82
     SECTION 14.3  Execution of Supplemental Indentures................................   83
     SECTION 14.4  Effect of Supplemental Indentures...................................   83
     SECTION 14.5  Conformity with Trust Indenture Act.................................   83
     SECTION 14.6  Reference in Bonds to Supplemental Indentures.......................   83

ARTICLE 15  SATISFACTION AND DISCHARGE.................................................   84
     SECTION 15.1  Satisfaction and Discharge of Bonds.................................   84
     SECTION 15.2  Satisfaction and Discharge of Indenture.............................   85
     SECTION 15.3  Application of Trust Money..........................................   85

ARTICLE 16  DEFEASANCE.................................................................   86
     SECTION 16.1  Defeasance..........................................................   86
     SECTION 16.2  Conditions to Defeasance............................................   86

ARTICLE 17  LIMITATION ON LIABILITY....................................................   88
     SECTION 17.1  Limitation on Liability.............................................   88

</TABLE>

                                     -iv-
<PAGE>   6

SCHEDULES:

     Schedule A  Permitted Liens
     Schedule B  Restrictive Agreements
     Schedule C  Outstanding Investments

EXHIBITS:

     Exhibit A - Form of Acceptable Guarantee
     Exhibit B - Form of Subordination Provisions

                                      -v-

<PAGE>   7

      Cross-reference sheet showing the location in this Indenture of the
provisions inserted pursuant to Sections 310 through 318, inclusive, of the
Trust Indenture Act of 1939, as amended.

<TABLE>
<CAPTION>
                  Trust Indenture
                  Act Section                                                  Indenture Section
                  -----------                                                  -----------------
<S>                                                                          <C>
Section 310(a)(1)                                                              11.7
                  (a)(2)                                                       11.7
                  (a)(3)                                                       N/A
                  (a)(4)                                                       N/A
                  (a)(5)                                                       11.7
                  (b)                                                          11.8
                  (c)                                                          N/A

Section 311(a)                                                                 11.4
                  (b)                                                          N/A
                  (c)                                                          N/A

Section 312(a)                                                                 N/A
                  (b)                                                          N/A
                  (c)                                                          N/A

Section 313(a)                                                                 11.12
                  (b)                                                          11.12
                  (c)                                                          11.12
                  (d)                                                          11.12

Section 314(a)                                                                 6.1
                  (b)(1)                                                       N/A
                  (b)(2)                                                       N/A
                  (c)(1)                                                       1.2
                  (c)(2)                                                       1.2
                  (c)(3)                                                       N/A
                  (d)                                                          N/A
                  (e)                                                          1.2
                  (f)                                                          N/A

Section 315(a)                                                                 11.1(j)
                  (b)                                                          N/A
                  (c)                                                          11.1(i)
                  (d)(1)                                                       11.1(j)
                  (d)(2)                                                       11.1(e)
                  (d)(3)                                                       11.1(a); 11.1(e)
                  (e)                                                          10.8

Section 316(a)(1)(A)                                                           10.2; 10.11
                  (a)(l)(B)                                                    10.12
</TABLE>
                                     -vi-

<PAGE>   8

<TABLE>
<CAPTION>
                  Trust Indenture
                  Act Section                                                  Indenture Section
                  -----------                                                  -----------------
<S>                                                                          <C>
                  (a)(2)                                                       N/A
                  (b)                                                          10.7
                  (c)                                                          11.1(f)

Section 317(a)(1)                                                              10.3
                  (a)(2)                                                       10.3
                  (b)                                                          11.11(c)

Section 318                                                                    1.6
</TABLE>
                                     -vii-

<PAGE>   9

       INDENTURE dated as of February 22, 2000 among NRG Northeast Generating
LLC, a Delaware limited liability company (the "Issuer"), the GUARANTORS party
hereto and THE CHASE MANHATTAN BANK, a New York banking corporation, as trustee
(the "Trustee").

                              W I T N E S S E T H:

       WHEREAS, the Issuer has duly authorized the creation of its bonds,
debentures, notes or other evidences of indebtedness to be issued in one or more
series (the "Bonds") up to such principal amount or amounts as may from time to
time be authorized in accordance with the terms of this Indenture (as
hereinafter defined); and the Issuer has duly authorized the execution and
delivery of this Indenture, to secure the Bonds and to provide for the
authentication and delivery thereof by the Trustee; and

       WHEREAS, all things necessary to make the Bonds, when executed by the
Issuer and authenticated and delivered by the Trustee as in this Indenture
provided, the valid, binding and legal obligations of the Issuer, and to
constitute these presents a valid indenture and agreement according to its
terms, have been done;

       NOW, THEREFORE, that, for and in consideration of the premises and of the
covenants herein contained and of the purchase of the Bonds by the holders
thereof, it is mutually covenanted and agreed, for the benefit of the parties
hereto and the equal and proportionate benefit of all Holders (as hereinafter
defined) of the Bonds, as follows:

                                    ARTICLE 1

                        DEFINITIONS AND OTHER PROVISIONS
                             OF GENERAL APPLICATION

       SECTION 1.1 Definitions; Construction. For all purposes of this Indenture
(and for all purposes of any other Financing Document (as hereinafter defined)
or any other instrument or agreement that incorporates provisions of this
Indenture by reference), except as otherwise expressly provided or unless the
context otherwise requires:

       (1) the terms defined in this Article have the meanings assigned to them
    in this Article, and include the plural as well as the singular;

       (2) all other terms used herein that are defined in the Trust Indenture
    Act (as hereinafter defined), either directly or by reference therein, have
    the meanings assigned to them therein;

       (3) except as otherwise expressly provided herein, (i) all accounting
    terms used herein shall be interpreted, (ii) all financial statements and
    all certificates and reports as to financial matters required to be
    delivered to the Trustee hereunder shall be prepared and (iii) all
    calculations made for the purposes of determining compliance with this

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   10
                                      -2-

    Indenture shall (except as otherwise expressly provided herein) be made in
    accordance with, or by application of, GAAP (as hereinafter defined);

       (4) all references in this Indenture (including the Appendices and
    Schedules hereto) to designated "Articles", "Sections" and other
    subdivisions are to the designated Articles, Sections and other subdivisions
    of this Indenture;

       (5) the words "herein", "hereof" and "hereunder" and other words of
    similar import refer to this Indenture as a whole and not to any particular
    Article, Section or other subdivision;

       (6) unless the context clearly indicates otherwise, pronouns having a
    masculine or feminine gender shall be deemed to include the other;

       (7) unless otherwise expressly specified, any agreement, contract or
    document defined or referred to herein shall mean such agreement, contract
    or document as in effect as of the date hereof, as the same may thereafter
    be amended, supplemented or otherwise modified from time to time in
    accordance with the terms of this Indenture and the other Financing
    Documents and shall include any agreement, contract, instrument or document
    in substitution or replacement of any of the foregoing entered into in
    accordance with the terms of this Indenture and the other Financing
    Documents;

       (8) any reference to any Person (as hereinafter defined) shall include
    its permitted successors and assigns in accordance with the terms of this
    Indenture and the other Transaction Documents and, in the case of any
    Governmental Authority (as hereinafter defined), any Person succeeding to
    its functions and capacities;

       (9) unless the context clearly requires otherwise, references to "Law"
    (as hereinafter defined) or to any particular Law shall include Laws or such
    particular Law as in effect at each, every and any of the times in question,
    including any amendments, replacements, supplements, extensions,
    modifications, consolidations, restatements, revisions or reenactments
    thereto or thereof, and whether or not in effect at the date of this
    Indenture; and

       (10) unless the context clearly intends to the contrary, all references
    in this Indenture to "this Indenture", the "benefits of this Indenture", the
    "Lien of this Indenture", or phrases of similar import shall be deemed to
    include reference to the Collateral Documents (as hereinafter defined) to
    the extent that reference to the Collateral Documents is not expressly made.

       "Acceptable Bank" means any commercial bank or other financial
institution which (a) is organized under the laws of the United States of
America, any state thereof or any other member of the Organization for Economic
Cooperation and Development or Japan and has an office in the United States of
America, (b) has capital, surplus and undivided profits of at least
$1,000,000,000 and (c) has outstanding long-term unsecured indebtedness which is
rated "A" or better by S&P and "A2" or better by Moody's (or an equivalent
rating by another nationally recognized statistical rating organization of
similar standing if neither such corporation is in the business of rating
long-term unsecured bank indebtedness).

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   11

                                      -3-

       "Acceptable Guarantor" means (i) an Acceptable Bank or (ii) NRG Energy or
any Affiliate of NRG Energy (except the Issuer or any of its Subsidiaries),
provided that NRG Energy or such Affiliate is (a) organized under the laws of
any state of the United States of America, (b) has an aggregate stockholders'
equity of at least $250,000,000 and (c) has outstanding long-term unsecured,
unguaranteed indebtedness which is rated "BBB-" or better by S&P and "Baa3" or
better by Moody's.

       "Acquisition Documents" means the Dunkirk/Huntley Acquisition Documents,
the Somerset Acquisition Documents, the Con Ed Acquisition Documents, the Oswego
Acquisition Documents or the CL&P Acquisition Documents or any combination
thereof (as the context requires).

       "Act" when used with respect to any Holder, shall have the meaning set
forth in Section 12.1.

       "Affected Property" means, with respect to any Event of Loss, the
property of the Issuer or any of the Guarantors that is lost, destroyed,
damaged, condemned or otherwise taken as a result of such Event of Loss.

       "Affiliate" with respect to any Person, means any other Person directly
or indirectly controlling or controlled by, or under direct or indirect common
control with, such Person. For purposes of this definition, the term "control"
(including the correlative meanings of the terms "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 policies of such Person, whether through the
ownership of voting securities or by contract or otherwise. In any event, any
member of the Issuer shall be deemed to be an Affiliate of the Issuer and any
Person that owns directly or indirectly 10% or more of securities having
ordinary voting power for the election of directors or other governing body of a
corporation or 10% or more of the Issuer or other ownership interests of any
other Person will be deemed to control such corporation or other Person.

       "Arthur Kill Operator" means NRG Arthur Kill Operations Inc., a Delaware
corporation.

       "Arthur Kill Power" means Arthur Kill Power LLC, a Delaware limited
liability company.

       "Assignment of Payments" means each Assignment of Payments dated February
22, 2000 between the Issuer and each Guarantor party to a Power Marketing
Agreement.

       "Astoria Operator" means NRG Astoria Gas Turbine Operations Inc., a
Delaware corporation.

       "Astoria Power" means Astoria Gas Turbine Power LLC, a Delaware limited
liability company.

       "Authenticating Agent" means any Person acting as Authenticating Agent
hereunder pursuant to Section 11.11.

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   12
                                      -4-

       "Authorized Agent" means any Paying Agent, Authenticating Agent or
Security Registrar or other agent appointed by the Trustee in accordance with
this Indenture to perform any function that this Indenture authorizes the
Trustee or such agent to perform.

       "Authorized Representative" of any of the Issuer, the Guarantors or any
other Person means the person or persons authorized to act on behalf of such
entity by its chief executive officer, president, chief operating officer, chief
financial officer or any vice president or its Board of Directors or any other
governing body of such entity.

       "Authorized Signatory" means any officer of the Trustee or any other
individual who shall be duly authorized by appropriate corporate action on the
part of the Trustee to authenticate Bonds.

       "Board of Directors", when used with respect to a corporation, means
either the board of directors of such corporation or any committee of that board
duly authorized to act for it, and when used with respect to a limited liability
company, partnership or other entity other than a corporation, any Person or
body authorized by the organizational documents or by the voting equity owners
of such entity to act for them.

       "Board Resolution" means a copy of a resolution certified by the
Secretary or an Assistant Secretary of the Issuer to have been adopted by the
Board of Directors of the Issuer and to be in full force and effect on the date
of such certification.

       "Bonds" shall have the meaning set forth in the preamble to this
Indenture.

       "Business Day" means a day which is neither a legal holiday nor a day on
which banking institutions (including, without limitation, the members of the
Federal Reserve System) are authorized or required by law, regulation or
executive order to close in The City of New York or the city of Minneapolis,
Minnesota.

       "Change of Control" means (a) the acquisition of ownership, directly or
indirectly, beneficially or of record or otherwise, by any Person or group
(within the meaning of the Exchange Act and the rules of the SEC thereunder as
in effect on the date hereof) other than NRG Energy or its wholly-owned
Subsidiaries, of ownership interests representing more than 50% of the aggregate
ordinary voting power represented by the membership interests of the Issuer; or
(b) the acquisition of direct or indirect control of the Issuer by any Person or
group other than NRG Energy or its wholly-owned Subsidiaries otherwise than as
described in clause (a); provided that there shall be no Change of Control if
either (i) after the occurrence of either of the events referred to in clause
(a) or (b) above, the Rating Agencies shall have confirmed their respective
ratings of the Bonds in effect immediately prior to the occurrence of such
events or (ii) holders of not less than 66% in aggregate principal amount of the
Outstanding Bonds approve the occurrence of such event.

       "CL&P" means Connecticut Light & Power Company, a Connecticut
corporation.

       "CL&P Acquisition Documents" means the Asset Sales Agreement between NRG
Energy and CL&P dated as of July 1, 1999 and each of the other agreements
attached as a form thereto.

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   13
                                      -5-

       "Closing Date" means February 22, 2000, the date on which the Initial
Bonds are first issued and sold hereunder.

       "Collateral" means all property and interests in property now owned or
hereafter acquired in or upon which a Lien has been or is purported or intended
to have been granted to the Trustee pursuant to the Collateral Documents.

       "Collateral Agency and Intercreditor Agreement" means the Collateral
Agency and Intercreditor Agreement dated as of February 22, 2000 among the
Issuer, the Initial Guarantors, the Working Capital Agent, the Trustee and the
Collateral Agent.

       "Collateral Agent" means The Chase Manhattan Bank, solely in its capacity
as collateral agent under the Collateral Agency and Intercreditor Agreement.

       "Collateral Documents" means the Security Agreement, the NRG Power
Marketing Security Agreement, the Collateral Agency and Intercreditor Agreement,
the Consent and Agreements and the Intercompany Notes.

       "Con Ed Acquisition Documents" means the Generating Plant and Gas Turbine
Asset Purchase and Sale Agreement dated as of January 27, 1999 between NRG
Energy and Consolidated Edison Company of New York, Inc. and each of the other
agreements attached as a form thereto.

       "Connecticut Jet Power" means Connecticut Jet Power LLC, a Delaware
limited liability company.

       "Consent and Agreements" means, collectively, (a) the consent and
agreement dated February 22, 2000 among Niagra Mohawk Power Corporation, Dunkirk
Power, Huntley Power and Oswego Power, (b) the consent and agreement dated
February 22, 2000 among Consolidated Edison Company of New York, Inc., Arthur
Kill Power and Astoria Power, (c) the consent and agreement dated February 22,
2000 among Eastern Edison Company, Blackstone Valley Electric Company, Newport
Electric Corporation and NRG Power Marketing and (d) the consent and agreement
dated February 22, 2000 between CL&P and NRG Power Marketing.

       "Corporate Services Agreement" means (a) the Corporate Services Agreement
between NRG Energy and Astoria Power dated June 25, 1999, (b) the Corporate
Services Agreement between NRG Energy and Arthur Kill Power dated June 25, 1999,
(c) the Corporate Services Agreement between NRG Energy and Dunkirk Power dated
June 11, 1999, (d) the Corporate Services Agreement between NRG Energy and
Huntley Power dated June 11, 1999, (e) the Amended and Restated Corporate
Services Agreement between NRG Energy and Somerset Power dated July 15, 1999,
(f) the Corporate Services Agreement between NRG Energy and Oswego Harbor Power
dated October 22, 1999, (g) the Corporate Services Agreement between NRG Energy
and Connecticut Jet Power dated December 15, 1999, (h) the Corporate Services
Agreement between NRG Energy and Devon Power dated December 15, 1999, (i) the
Corporate Services Agreement between NRG Energy and Middletown Power dated
December 15, 1999, (j) the Corporate Services Agreement between NRG Energy and
Montville Power dated December 15, 1999 and (k) the Corporate Services Agreement
between NRG

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   14
                                      -6-

Energy and Norwalk Power dated December 15, 1999, or any combination thereof (as
the context requires).

       "Corporate Trust Office" means the principal office of the Trustee or
Security Registrar at which the corporate trust business of the Trustee or
Security Registrar, as the case may be, shall at any particular time be
principally administered, which at the time of the execution of this Indenture
is, in each case, located at 450 W. 33rd Street, New York, New York 10001,
Attention: Capital Markets Fiduciary Services.

       "Covenant Defeasance" has the meaning set forth in Section 16.1.

       "Custodian" has the meaning set forth in Section 2.5.

       "Debt Service Coverage Ratio" for any period means, on a consolidated
basis of the Issuer and the Guarantors (excluding the Unrestricted Subsidiaries
and without duplication), the ratio of, (x) all Revenues less Operating Expenses
(other than nonrecurring expenses in connection with the issuance of Permitted
Indebtedness), less all capital expenditures (unless funded with Permitted
Indebtedness), to (y) the aggregate of principal, interest and fees payable on
the Outstanding Bonds and all other Permitted Indebtedness (other than
Subordinated Indebtedness, fees payable in connection with the issuance of
Permitted Indebtedness and principal payments under the Working Capital
Facility, provided that such amounts remain available to be drawn under the
Working Capital Facility or are refinanced under a replacement Working Capital
Facility) plus payments required to be made under any Interest Rate Agreements,
less payments to be received under any Interest Rate Agreement for such period.

       "Debt Service Reserve Account" has the meaning set forth in Section 4.1.

       "Debt Service Reserve Amount" means, as of any date of determination, the
aggregate amount of cash on deposit in the Debt Service Reserve Account, plus
the aggregate fair market value of all Permitted Investments on deposit therein
at such time, plus the amount available to be drawn or demanded under all Debt
Service Reserve Support Instruments credited to such account at such time.

       "Debt Service Reserve Guarantee" means a guarantee of an Acceptable
Guarantor executed and delivered to the Trustee to support the obligations of
the Issuer hereunder with respect to all or a part of the Issuer's obligation to
fund the Debt Service Reserve Account and permitting demands for payment
thereunder as contemplated by Section 4.1, in each case:

       (i) in substantially the form attached hereto as Exhibit A;

       (ii) with a term ending no earlier than the termination or satisfaction
   and discharge of this Indenture; and

       (iii) providing for the amount thereof to be made available in full to
   the Trustee in multiple payments upon the demand of the Trustee.

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   15
                                      -7-

       "Debt Service Reserve Letter of Credit" means one or more irrevocable
direct pay letters of credit available for the purpose of drawing to pay
principal and interest on the Bonds in an amount up to the Debt Service Reserve
Requirement and any extensions thereof or any substitute letter of credit
therefor in the stated amount contained in such extension or substitute and
permitting draws thereon as contemplated by Section 4.1, in each case:

       (i) issued to the Trustee (for the benefit of the Holders) by an
   Acceptable Bank;

       (ii) expiring not earlier than the latest to occur of (a) the date on
   which the stated amount thereof is drawn down to zero, (b) the date on which
   the Trustee returns the letter of credit to the issuer thereof for
   cancellation and (c) the maturity of any of the Guaranteed Obligations;

       (iii) providing for the amount thereof to be made available in full to
   the Trustee in multiple drawings conditioned only upon the presentation of a
   sight draft accompanied by the applicable certificate in the form attached to
   such letter of credit; and

       (iv) with respect to which the Issuer certifies in an Officer's
   Certificate that such Letter of Credit does not constitute Indebtedness of
   the Issuer and is not secured by a Lien on any of the property of the Issuer.

       "Debt Service Reserve Requirement" means, at any date of determination,
the sum of the Required Amounts for all series of Bonds then Outstanding.

       "Debt Service Reserve Shortfall" means, as at any date of determination,
the excess of the Debt Service Reserve Requirement over the Debt Service Reserve
Amount as at such date, if any.

       "Debt Service Reserve Support Instrument" means one or more Debt Service
Reserve Guarantees or one or more Debt Service Reserve Letters of Credit or both
(as the context requires).

       "Default" means an event or condition that, with the giving of notice,
lapse of time or failure to satisfy certain specified conditions, or any
combination thereof, would become an Event of Default if not cured or remedied.

       "Designation Letter" has the meaning given to such term in the Collateral
Agency and Intercreditor Agreement.

       "Devon Operator" means NRG Devon Operations Inc., a Delaware corporation.

       "Devon Power" means Devon Power LLC, a Delaware limited liability
company.

       "Distribution Compliance Period" means, with regard to Bonds of any
series offered and sold in their initial distribution outside the United States
in reliance on Regulation S, the period of 40 consecutive days beginning on the
later of (i) the date on which the Bonds of such series are first offered to
persons other than distributors (as defined in Regulation S) in reliance on
Regulation S (according to a written notice to the Trustee by the initial
purchasers

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   16
                                      -8-

thereof) and (ii) the date on which the same such Bonds are initially issued,
authenticated and sold.

       "Dunkirk Operator" means NRG Dunkirk Operations Inc., a Delaware
corporation.

       "Dunkirk Power" means Dunkirk Power LLC, a Delaware limited liability
company.

       "Dunkirk/Huntley Acquisition Documents" means the Asset Sales Agreement
between NRG Energy and Niagara Mohawk Power Corporation dated as of December 23,
1998 and each of the other agreements attached as a form thereto.

       "Environmental Approvals" means Governmental Approvals required under
applicable Environmental Laws.

       "Environmental Laws" means any and all Laws (as well as obligations,
duties and requirements relating thereto under common law) relating to: (i)
noise, emissions, discharges, spills, releases or threatened releases of
pollutants, contaminants, environmentally regulated materials, materials
containing environmentally regulated materials, or hazardous or toxic materials
or wastes into ambient air, surface water, groundwater, watercourses, publicly
or privately-owned treatment works, drains, sewer systems, wetlands, septic
systems or onto land surface or subsurface strata; (ii) the use, treatment,
storage, disposal, handling, manufacture, processing, distribution,
transportation, or shipment of environmentally regulated materials, materials
containing environmentally regulated materials or hazardous and/or toxic wastes,
material, products or by-products (or of equipment or apparatus containing
environmentally regulated materials); (iii) pollution or the protection of human
health, the environment or natural resources or (iv) zoning and land use.

       "ERISA" means the Employee Retirement Income Security Act of 1974, as
amended and in effect from time to time.

       "Event of Default" means any event or condition specified as such in
Section 10.1 hereof that shall have continued for the applicable period of time,
if any, therein designated.

       "Event of Eminent Domain" means any compulsory transfer or taking or
transfer under threat of compulsory transfer or taking of any material part of
the collateral by any Governmental Authority.

       "Event of Loss" means an event which causes all or a portion of any
Facility to be damaged, destroyed or rendered unfit for normal use for any
reason whatsoever including, but not limited to, an Event of Eminent Domain.

       "Exchange Act" means the Securities Exchange Act of 1934, as amended and
in effect from time to time.

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   17
                                      -9-

       "Facilities" means the electric generation plants and the related
facilities and equipment owned by the Initial Guarantors and any Subsequent
Guarantors and, in each case, the business and activities related thereto.

       "Federal Bankruptcy Code" means Title 11 of the United States Code, as
amended and in effect from time to time.

       "Financing Documents" means this Indenture, any Series Supplemental
Indenture the Bonds, the Collateral Documents and the Registration Rights
Agreement.

       "First Series Supplemental Indenture" means the First Supplemental
Indenture dated as of February 22, 2000 among the Trustee, the Issuer and the
Guarantors.

       "Funds Administration Agreement" means the Funds Administration Agreement
dated February 22, 2000 among the Issuer and each of the Guarantors.

       "GAAP" means generally accepted accounting principles in effect in the
United States applied on a basis consistent with the principles, methods,
procedures and practices employed in the preparation of the Issuer's audited
financial statements, including, without limitation, those set forth in the
opinions and pronouncements of the Accounting Principles Board of the American
Institute of Certified Public Accountants and statements and pronouncements of
the Financial Accounting Standards Board or in such other statements by such
other entity as approved by a significant segment of the accounting profession.

       "Global Bonds" means a Bond in global form that evidences all or part of
the Bonds and is authenticated and delivered to, and registered in the name of,
the Registered Depositary for such securities or a nominee thereof.

       "Good Faith Contest" means the contest of an item if such item is
diligently contested in good faith by appropriate proceedings timely instituted
and (a) adequate reserves are established if required by and in accordance with
GAAP with respect to the contested item and held in cash or investments and (b)
during the period of such contest the enforcement of any contested item is
effectively stayed.

       "Governmental Approvals" means any authorization, consent, approval,
order, license, franchise, ruling, permit, certification, waiver, exemption,
filing or registration by or with any Governmental Authority (including, without
limitation, Environmental Approvals, zoning variances, special exceptions and
non-conforming uses) relating to the construction, ownership, operation or
maintenance of the Facilities or to the execution, delivery or performance of
any Transaction Document.

       "Governmental Authority" means any nation, state, sovereign or
government, any federal, regional, state, municipal, local or political
subdivision thereof or any department, commission, board, bureau, agency,
instrumentality, judicial or administrative body or other entity exercising
executive, legislative, judicial, regulatory or administrative functions of or
pertaining to government.

       "Guaranteed Obligations" has the meaning set forth in Section 5.1.

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   18
                                      -10-

       "Guarantor" means each of the Initial Guarantors and any Subsequent
Guarantor.

       "Guarantee" means, with respect to any Person, any obligation, contingent
or otherwise, of such Person directly or indirectly guaranteeing in any manner
any Indebtedness or other obligation of any other Person and, without limiting
the generality of the foregoing, any obligation, direct or indirect, contingent
or otherwise, of such Person (i) to purchase or pay (or advance or supply funds
for the purchase or payment of) such Indebtedness or other obligation (whether
arising by virtue of Issuer arrangements, by agreement to keep-well, to purchase
assets, goods, bonds or services, to take-or-pay, or to maintain financial
statement conditions or otherwise), (ii) entered into for the purpose of
assuring in any other manner the obligee of such Indebtedness or other
obligation of the payment thereof or to protect such obligee against loss in
respect thereof (in whole or in part) or (iii) to reimburse any Person for the
payment by such Person under any letter of credit, surety, bond or other
guaranty issued for the benefit of such other Person, provided that the term
"Guarantee" shall not include endorsements for collection or deposit in the
ordinary course of business. The term "Guarantee" or "Guaranteed" used as a verb
has a correlative meaning.

       "Hedging Agreement" means any interest rate protection agreement, foreign
currency exchange agreement, commodity price protection agreement or other
interest or currency exchange rate or commodity price hedging arrangement
entered into in the ordinary course of business and not for speculative
purposes.

       "Holder" means a Person in whose name a Bond is registered in the
Security Register.

       "Huntley Operator" means NRG Huntley Operations Inc., a Delaware
corporation.

       "Huntley Power" means Huntley Power LLC, a Delaware limited liability
company.

       "Indebtedness" of any Person means, without duplication, (a) all
obligations of such Person for borrowed money or with respect to deposits or
advances of any kind, (b) all obligations of such Person evidenced by bonds,
debentures, notes or similar instruments, (c) all obligations of such Person
under conditional sale or other title retention agreements relating to property
acquired by such Person, (d) all obligations of such Person upon which interest
charges are customarily paid, (e) all obligations of such Person in respect of
the deferred purchase price of property or services (excluding trade and other
accounts payable incurred in the ordinary course of business so long as such
trade accounts payable are payable and paid within 90 days of the date the
respective goods are delivered or the respective services rendered), (f) all
Indebtedness of others secured by (or for which the holder of such Indebtedness
has an existing right, contingent or otherwise, to be secured by) any Lien on
property owned or acquired by such Person, whether or not the Indebtedness
secured thereby has been assumed, (g) all Indebtedness of any other Person
guaranteed by such person or for which such Person shall otherwise (including
payments pursuant to any keep-well, make-well or similar arrangement) become
directly or indirectly liable, (h) all capital lease obligations of such Person,
(i) all obligations, contingent or otherwise, of such Person as an account party
or issuer in respect of letters of credit

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   19
                                      -11-

or the like and (j) all obligations, contingent or otherwise, of such Person in
respect of bankers' acceptances. The Indebtedness of any Person shall include
the Indebtedness of any other entity

       (including any partnership in which such Person is a general partner) to
the extent such Person is liable therefor as a result of such Person's ownership
interest in or other relationship with such entity, except to the extent the
terms of such Indebtedness provide that such Person is not liable therefor.

       "Indemnification Agreement" means the indemnification agreement dated
December 23, 1999 by NRG Energy in favor of The Chase Manhattan Bank and
Citibank, N.A. as Lender Representatives (as defined therein) and the
Indemnified Parties (as defined therein).

       "Indemnification Consent Agreement" means the Indemnification Consent
Agreement dated February 22, 2000 among NRG Energy, the Issuer, the Initial
Purchasers, the Trustee and the Collateral Agent.

       "Indenture" means this instrument entered into by the Issuer, the
Guarantors and the Trustee.

       "Initial Bonds" means the Bonds issued by the Issuer on the Closing Date
under the First Series Supplemental Indenture.

       "Initial Guarantors" means each of Arthur Kill Power, Astoria Power,
Connecticut Jet Power, Devon Power, Dunkirk Power, Huntley Power, Middletown
Power, Montville Power, Norwalk Power, Oswego Harbor Power and Somerset Power.

       "Initial Purchasers" means Chase Securities, Inc., Salomon Smith Barney
Inc., ABN AMRO Incorporated, CIBC World Markets and Dresdner Kleinwort Benson
N.A. LLC as the initial purchasers of the Initial Bonds.

       "Intercompany Loan" means Indebtedness to the Issuer or any Guarantor by
the Issuer or any Guarantor. "Intercompany Notes" means the notes evidencing
indebtedness owed by the Guarantors to the Issuer dated February 22, 2000.

       "Interest Rate Agreement" means any interest rate protection agreement,
interest rate future, interest rate option, interest rate swap, interest rate
cap or other interest rate hedge arrangement, to which the Issuer or any
Guarantor is a party, entered into in the ordinary course of business in
connection with Permitted Indebtedness and not for speculative purposes.

       "Investment" means, for any Person: (i) the acquisition (whether for
cash, property of such Person, services or securities or otherwise) of capital
stock, bonds, notes, debentures or other ownership interests or other securities
of any other Person or any agreement to make any such acquisition (including,
without limitation, any "short sale" or any sale of any securities at a time
when such securities are not owned by the Person entering into such short sale),
(ii) the making of any deposit with, or advance, loan or other extension of
credit to, any other Person (including the purchase of property from another
Person subject to an

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   20
                                      -12-

understanding or agreement, contingent or otherwise, to resell such property to
such Person, but excluding any such advance, loan or extension of credit arising
in connection with the sale of inventory or supplies by such Person in the
ordinary course of business), (iii) the entering into of any Guarantee of, or
any other contingent obligation with respect to, Indebtedness or other liability
of any other Person and (without duplication) any amount committed to be
advanced, lent or extended to such Person or (iv) the entering into of any
Hedging Agreement.

       "Issuer" has the meaning set forth in the preamble to this Indenture.

       "Issuer Order" means, respectively, a written request or order signed in
the name of the Issuer by one of its Authorized Representatives, and by its
treasurer, secretary, or one of its assistant treasurers or assistant
secretaries.

       "Issuer's Obligations" has the meaning set forth in Section 17.1.

       "Law" means any constitutional provision, law, statute, rule, regulation,
ordinance, treaty, order, decree, judgment, decision, certificate, holding,
injunction, Governmental Approval, consent or other requirement of any
Governmental Authority, enforceable at law or in equity, along with the
interpretation and administration thereof by any Governmental Authority charged
with the interpretation or administration thereof.

       "Legal Defeasance" has the meaning set forth in Section 16.1.

       "Lien" means, with respect to any asset, (a) any mortgage, deed of trust,
lien, pledge, hypothecation, encumbrance, charge or security interest in, on or
of such asset, (b) the interest of a vendor or a lessor under any conditional
sale agreement, capital lease or title retention agreement (or any financing
lease having substantially the same economic effect as any of the foregoing)
relating to such asset and (c) in the case of securities, any purchase option,
call or similar right of a third party with respect to such securities.

       "Loss Proceeds" means all insurance proceeds or other amounts received on
account of any Event of Loss.

       "Majority Holders" means the holders of more than 50% in aggregate
principal amount of (i) the Bonds then Outstanding or (ii) the Outstanding Bonds
of the applicable series, as the case may be.

       "Mandatory Redemption Account" has the meaning given to such term in
Section 8.2.

       "Material Adverse Effect" means a material adverse effect on (a) the
business, assets, operations, prospects or condition, financial or otherwise, of
the Issuer and the Guarantors taken as a whole, (b) the ability of any Obligor
to perform any of its obligations under any Transaction Document to which it is
a party, which obligations are material to the Issuer and the Guarantors, taken
as a whole, or (c) the material rights of or benefits available to the Holders
or the Trustee, as representative of the Holders.

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   21
                                      -13-

       "Member" means each of NRG Eastern LLC and Northeast Generation Holding
LLC, which are at the date of this Indenture the sole holders of an equity
interest in the Issuer, and any future members or equity holders of the Issuer.

       "Middletown Operator" means NRG Middletown Operations Inc., a Delaware
corporation.

       "Middletown Power" means Middletown Power LLC, a Delaware limited
liability company.

       "Montville Operator" means NRG Montville Operations Inc., a Delaware
corporation.

       "Montville Power" means Montville Power LLC, a Delaware limited liability
company.

       "Moody's" means Moody's Investors Service, Inc. or any successor thereto.

       "Non-Recourse Obligations" means Indebtedness or other obligations or
liabilities (i) as to which neither the Issuer nor any of the Guarantors (a)
provides credit support of any kind (including any undertaking, agreement or
instrument that would constitute Indebtedness) (b) is directly or indirectly
liable (as a guarantor or otherwise) other than pursuant to a pledge by the
Issuer of an equity interest in the obligor of the Indebtedness or (c)
constitutes the lender and (ii) no default with respect to which (including any
rights any Person may have to take enforcement action against an Unrestricted
Subsidiary) would permit (upon notice, lapse of time or both) any holder of any
Indebtedness of the Issuer or any of Guarantor to declare a default on such
Indebtedness or cause the payment thereof to be accelerated or payable prior to
its stated maturity.

       "Norwalk Power" means Norwalk Power LLC, a Delaware limited liability
company.

       "Norwalk Operator" means NRG Norwalk Harbor Operations Inc., a Delaware
corporation.

       "NRG Energy" means NRG Energy, Inc., a Delaware corporation.

       "NRG Operations" means NRG Operating Services, Inc., a Delaware
corporation.

       "NRG Power Marketing" means NRG Power Marketing Inc., a Delaware
corporation.

       "NRG Power Marketing Security Agreement" means the NRG Power Marketing
Security Agreement dated February 22, 2000 between NRG Power Marketing, Inc. and
the Collateral Agent.

       "Obligations" shall have the meaning set forth in Section 16.2.

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   22
                                      -14-

       "Obligor" means the Issuer and each Guarantor.

       "Officer's Certificate" means, in the case of the Issuer,
a certificate of an Authorized Representative of the Issuer and signed by a
managing director, president, a vice president, the treasurer, an assistant
treasurer, the secretary or an assistant secretary of the Issuer.

       "Operating Expenses" means for any period, the sum, computed without
duplication, of all costs and expenses incurred (in the case of the Issuer) by
the Issuer or (in the case of any Guarantor) by such Guarantor during such
period (or, in the case of any future period, projected to be paid or payable
during such period) in connection with the operation, maintenance and
administration of the Facilities.

       "Operation and Maintenance Agreement" means (a) the Operation and
Maintenance Agreement dated June 25, 1999 between the Astoria Operator and
Astoria Power, (b) the Operation and Maintenance Agreement dated June 25, 1999
between the Arthur Kill Operator and Arthur Kill Power, (c) the Operation and
Maintenance Agreement dated December 15, 1999 between the Middletown Operator
and Connecticut Jet Power, (d) the Operation and Maintenance Agreement dated
December 15, 1999 between the Devon Operator and Devon Power, (e) the Operation
and Maintenance Agreement dated June 11, 1999 between the Dunkirk Operator and
Dunkirk Power, (f) the Operation and Maintenance Agreement dated June 11, 1999
between the Huntley Operator and Huntley Power, (g) the Operation and
Maintenance Agreement dated December 15, 1999 between the Middletown Operator
and Middletown Power, (h) the Operation and Maintenance Agreement dated December
15, 1999 between the Montville Operator and Montville Power, (i) the Operation
and Maintenance Agreement dated December 15, 1999 between the Norwalk Operator
and Norwalk Power, (j) the Operation and Maintenance Agreement dated October 22,
1999 between the Oswego Operator and Oswego Harbor Power and (k) the Amended and
Restated Operation and Maintenance Agreement dated July 15, 1999 between the
Somerset Operator and Somerset Power and any successor or replacement
agreements, or any combination thereof (as the context requires).

       "Operator" means the Arthur Kill Operator, the Astoria Operator, the
Connecticut Jet Operator, the Devon Operator, the Dunkirk Operator, the Huntley
Operator, the Middletown Operator, the Montville Operator, the Norwalk Operator,
the Oswego Operator or the Somerset Operator, or any combination thereof (as the
context requires).

       "Opinion of Counsel" means a written opinion of counsel for any Person
either expressly referred to herein or otherwise reasonably satisfactory to the
Trustee which may include, without limitation, counsel for the Issuer, whether
or not such counsel is an employee of the Issuer.

       "Oswego Acquisition Documents" means the Asset Sales Agreement dated as
of April 1, 1999 between NRG Energy, Niagara Mohawk Power Corporation, Rochester
Gas and Electric Corporation and Oswego Harbor Power and each of the other
agreements attached as a form thereto.

       "Oswego Harbor Power" means Oswego Harbor Power LLC, a Delaware limited
liability company.

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   23

                                      -15-

       "Oswego Operator" means NRG Oswego Harbor Power Operations Inc., a
Delaware corporation.

       "Outstanding", when used with respect to Bonds or any principal amount
thereof, means, as of the date of determination, all Bonds theretofore
authenticated and delivered under this Indenture, except:

       (i)  Bonds theretofore canceled by the Trustee or delivered to the
   Trustee for cancellation;

       (ii) Bonds for whose redemption money in the necessary amount has been
   theretofore deposited in trust with the Trustee; provided that if such
   Bonds are to be redeemed prior to the maturity thereof, notice of such
   redemption has been duly given pursuant to Article 8 or provision
   therefor satisfactory to the Trustee has been made;

       (iii)  Bonds or portions thereof deemed to have been paid within the
   meaning of Section 14.1;

       (iv)  Bonds as to which defeasance has been effected pursuant to
   Article 16; and

       (v) Bonds which have been paid pursuant to Section 2.9 or that have been
   exchanged for other Bonds or Bonds in lieu of which other Bonds have been
   authenticated and delivered pursuant to this Indenture other than any
   Bonds in respect of which there shall have been presented to the Trustee
   proof satisfactory to it that such Bonds are held by a bona fide
   purchaser in whose hands such Bonds constitute valid obligations of the
   Issuer;

provided, however, that in determining whether the Holders of the requisite
principal amount of the Outstanding Bonds of any series have given any request,
demand, authorization, direction, notice, consent or waiver hereunder, Bonds
owned by the Issuer or any of its Subsidiaries or any Affiliate of the Issuer or
any of its Subsidiaries shall be disregarded and deemed not to be Outstanding,
except that, in determining whether the Trustee shall be protected in relying
upon any such request, demand, authorization, direction, notice, consent or
waiver, only Bonds which the Trustee knows to be so owned shall be so
disregarded. Bonds so owned which have been pledged in good faith may be
regarded as Outstanding if the pledgee establishes to the satisfaction of the
Trustee the pledgee's right to act with respect to such Bonds and that the
pledgee is not the Issuer or a Subsidiary or any Affiliate of the Issuer or any
Subsidiary.

       "Paying Agent" means any Person acting as Paying Agent hereunder pursuant
to Section 11.11.

       "Permitted Indebtedness" means (a) the Bonds; (b) Indebtedness, provided,
that after giving effect to the incurrence of such Indebtedness on a pro forma
basis and the application of the net proceeds thereof (A) there is no current
Default or Event of Default unless the proceeds of such Indebtedness are applied
to cure, and such application does cure, such Default or Event of Default; and
(B) the Issuer provides an Officer's Certificate that certifies that (x) the
minimum annual Projected Debt Service Coverage Ratio for each calendar year
commencing with the year in which such Indebtedness is incurred through the
final maturity of

                       NRG Northeast Generating Indenture
                       ----------------------------------
<PAGE>   24

                                      -16-

the Bonds with the longest maturity is no less than 2.00 to 1; and (y) the Debt
Service Coverage Ratio for the preceding four consecutive fiscal quarters (taken
as a whole) was not less than 2.00 to 1 (or such shorter period covering the
quarters ended subsequent to the issuance of the Bonds); and (C) each of the
Rating Agencies confirms its then current rating on the Bonds; (c) Indebtedness
for working capital purposes not to exceed in the aggregate the sum of
$50,000,000 plus, upon the acquisition of any Subsequent Guarantor or any
additional facility by a Guarantor or the Issuer, 4% of the Indebtedness
incurred by the Issuer in connection with such acquisition; (d) Indebtedness
related to Permitted Liens; (e) Indebtedness of the Issuer to a Guarantor; (f)
Indebtedness represented by Hedging Agreements; (g) Indebtedness in the form of
performance or payment guarantees entered into by the Issuer in the ordinary
course of business in connection with (i) fuel procurement by NRG Power
Marketing directly related to the Facilities, (ii) sales or purchases of
emissions allowances by NRG Power Marketing directly related to the facilities
and (iii) sales of electrical generating capacity, energy or ancillary services
by NRG Power Marketing directly related to the Facilities in each case, so long
as such activities are not for speculative purposes; (h) Indebtedness in respect
of letters of credit, surety bonds or performance bonds issued in the ordinary
course of business; (i) trade accounts payable or other similar indebtedness
arising, and accrued expenses incurred, in the ordinary course of business (but
not in any case for borrowed money) (j) other Senior Debt not to exceed
$15,000,000; and (k) Subordinated Indebtedness, provided, that no such Permitted
Indebtedness shall be secured by the Collateral unless the lender or lenders
thereof or its or their representative shall have executed, and been designated
a "Secured Party" pursuant to, a Designation Letter delivered to the Collateral
Agent.

       "Permitted Investments" means investments in securities or other
instruments that are: (i) direct obligations of the United States, or any agency
thereof; (ii) obligations fully guaranteed by the United States or any agency
thereof; (iii) certificates of deposit issued by commercial banks under the laws
of the United States or any political subdivision thereof or under the laws of
Canada, Japan or any country that is a member of the European Economic Union
having a combined capital and surplus of at least $500,000,000 and having
long-term unsecured debt securities rated "A" or better by S&P and "A2" or
better by Moody's (but at the time of investment not more than $25,000,000 may
be invested in such certificates of deposit from any one bank); (iv) repurchase
obligations for underlying securities of the types described in clauses (i) and
(ii) above, entered into with any commercial bank meeting the qualifications
specified in clause (iii) above or any other financial institution having
long-term unsecured debt securities rated "A" or better by S&P and "A2" or
better by Moody's in connection with which such underlying securities are held
in trust or by a third-party custodian; (v) open market commercial paper of any
corporation incorporated or doing business under the laws of the United States
or of any political subdivision thereof having a rating of at least "A-1" from
S&P and "P-1" from Moody's (but at the time of investment not more than
$25,000,000 may be invested in such commercial paper from any one company); (vi)
investments in money market funds having a rating assigned by each of the Rating
Agencies equal to the highest rating assigned thereby to money market funds or
money market mutual funds sponsored by any securities broker dealer of
recognized national standing (or an Affiliate thereof), having an investment
policy that requires substantially all the invested assets of such fund to be
invested in investments described in any one or more of the foregoing clauses
and having a rating of "A" or better by S&P and "A2" or better by Moody's
(including money market funds or money market mutual funds for which the Trustee
in its individual capacity or any of its affiliates is investment manager or
adviser) or

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<PAGE>   25

                                      -17-

(vii) a deposit of any bank (including the Trustee), trust company or financial
institution authorized to engage in the banking business having a combined
capital and surplus of at least US$500,000,000, whose long-term, unsecured debt
is rated "A" or higher by S&P and "A2" of higher by Moody's.

       "Permitted Liens" means:

       (a) Liens in favor of the Issuer or any Guarantor;

       (b) Liens imposed by law for taxes, assessments or governmental charges
   that are not yet delinquent and remain payable without penalty or that
   are being contested in good faith by appropriate proceedings;

       (c) carriers', warehousemen's, mechanics', materialmen's, repairmen's and
   other like Liens imposed by law, arising in the ordinary course of business
   and securing obligations that are not overdue by more than 45 days or are
   being contested in good faith by appropriate proceedings;

       (d) pledges and deposits made in the ordinary course of business in
   compliance with workers' compensation, unemployment insurance and other
   social security laws or regulations or other statutory obligations of the
   Issuer or any Guarantor;

       (e) cash deposits or rights of set-off to secure the performance of bids,
   tenders, trade contracts, leases, statutory obligations, surety and appeal
   bonds, performance bonds, government contracts and other obligations of a
   like nature (other than for payment obligations of borrowed money), in each
   case in the ordinary course of business;

       (f) judgment liens in respect of judgments that do not give rise to an
   Event of Default under clause (g) of Section 10.1;

       (g) encumbrances identified on Schedule A hereto, and other easements,
   zoning restrictions, rights-of-way and similar charges or encumbrances on
   real property imposed by law or arising in the ordinary course of business
   that do not secure any monetary obligations and do not materially detract
   from the value of the affected property or interfere with the ordinary
   conduct of business of the Issuer or any Guarantor;

       (h) Liens securing Hedging Agreements which Hedging Agreements relate to
   Indebtedness that is secured by Liens otherwise permitted under this
   Indenture;

       (i) Liens that are incidental to the business of the Issuer or the
   Guarantors, are not for borrowing money and are not material, taken as a
   whole, to the business of the Issuer and the Guarantors;

       (j) Liens created or granted pursuant to the Collateral Documents; and

       (k) Liens with respect to other Permitted Indebtedness (other than
   Subordinated Indebtedness), provided that the Bonds are secured on an equal
   and ratable basis with the obligation so secured until such obligation is no
   longer secured.

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                                      -18-

       "Person" means any individual, sole proprietorship, corporation, company,
partnership, joint venture, limited liability company, trust, unincorporated
association, institution, Governmental Authority or any other entity.

       "Place of Payment", when used with respect to the Bonds of any series
means the office or agency maintained pursuant to Section 11.11 and such other
place or places, if any, where the principal of, and premium, if any, and
interest on the Bonds of such series are payable as specified herein or in any
Series Supplemental Indenture setting forth the terms of the Bonds of such
series.

       "Power Sales Agreement" means each transition agreement and each other
contract or agreement, other than Power Marketing Agreements, now existing or
entered into in the future by the Issuer or any of the Guarantors for the sale
of electrical generating capacity, electrical energy, ancillary services or any
combination thereof.

       "Power Marketing Agreement" means (a) the Power Sales and Agency
Agreement dated June 25, 1999 between NRG Power Marketing and Astoria Power, (b)
the Power Sales and Agency Agreement dated June 25, 1999 between NRG Power
Marketing and Arthur Kill Power, (c) the Power Sales and Agency Agreement dated
December 15, 1999 between NRG Power Marketing and Connecticut Jet Power, (d) the
Power Sales and Agency Agreement dated December 15, 1999 between NRG Power
Marketing and Devon Power, (e) the Power Sales and Agency Agreement dated June
11, 1999 between NRG Power Marketing and Dunkirk Power, (f) the Power Sales and
Agency Agreement dated June 11, 1999 between NRG Power Marketing and Huntley
Power, (g) the Power Sales and Agency Agreement dated December 15, 1999 between
NRG Power Marketing and Middletown Power, (h) the Power Sales and Agency
Agreement dated December 15, 1999 between NRG Power Marketing and Montville
Power, (i) the Power Sales and Agency Agreement dated December 15, 1999 between
NRG Power Marketing and Norwalk Power, (j) the Power Sales and Agency Agreement
dated October 22, 1999 between NRG Power Marketing and Oswego Harbor Power and
(k) the Amended and Restated Power Sales and Agency Agreement dated July 15,
1999 between NRG Power Marketing and Somerset Power, or any combination thereof
(as the context requires).

       "Predecessor Bonds", with respect to any particular Bond, means any
previous Bond evidencing all or a portion of the same debt as that evidenced by
such particular Bond; for the purposes of this definition, any Bond
authenticated and delivered under Section 2.9 in lieu of a lost, destroyed or
stolen Bond shall be deemed to evidence the same debt as the lost, destroyed or
stolen Bond.

       "Projected Debt Service Coverage Ratio" means, at any time of
determination thereof, a projection of the Debt Service Coverage Ratio over the
period specified, prepared by the Issuer in good faith based upon assumptions
consistent in all material respects with the Transaction Documents, historical
operating results, if any, and the Issuer's good faith projections of future
Revenues and Operating Expenses of the Issuer and the Guarantors in light of the
then existing or reasonably expected regulatory and market environments in the
markets in which the Facilities are or will be operated and upon the assumption
that no early redemption or prepayment of the Bonds of any series will be made
prior to the stated maturity of such series of Bonds. Whenever this Indenture
provides for the determination of a Projected Debt Service

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                                      -19-

Coverage Ratio, the Projected Debt Service Coverage Ratio shall be set forth in
an Officer's Certificate of the Issuer filed with the Trustee stating that,
based upon reasonable investigation and review, the Projected Debt Service
Coverage Ratio is based on the criteria set forth in the preceding sentence.

       "Prudent Industry Practice" means any of those practices, methods,
standards and acts (including but not limited to the practices, methods and acts
engaged in or approved by a significant portion of the electric power generation
industry in the United States) that, at a particular time, in the exercise of
reasonable judgment in light of the facts known or that should reasonably have
been known at the time a decision was made, could have been expected to
accomplish the desired result consistent with good business practices,
reliability, economy, safety and expedition, and which practices generally
conform to applicable law and governmental approvals. "Prudent Industry
Practice" is not intended to be limited to optimal practices that could be used
to accomplish a desired result.

       "PUHCA" means the Public Utility Holding Company Act of 1935, as
amended and in effect from time to time.

       "Rating Agencies" means S&P and Moody's, or another nationally
recognized credit rating agency of similar standing if either of the foregoing
corporations is not in the business of rating the subject of such rating.

       "Redemption Date" has the meaning set forth in Section 8.2.

       "Redemption Price" means, with respect to any Bond Outstanding on any
Redemption Date, an amount equal to the principal of such Bond Outstanding on
such date, plus interest accrued and unpaid to but excluding such Redemption
Date.

       "Registered Depositary" means The Depository Trust Company, having a
principal office at 55 Water Street, New York, New York 10041-0099, together
with any Person succeeding thereto by merger, consolidation or acquisition of
all or substantially all of its assets, including substantially all of its
securities payment and transfer operations.

       "Registration Rights Agreement" means the Registration Rights Agreement
dated February 15, 2000 among the Issuer, the Guarantors and the Initial
Purchasers.

       "Regular Record Date", for any Bond of a series for the Scheduled Payment
Date of any installment of principal thereof or payment of interest thereon,
means the 16th day (whether or not a Business Day) next preceding such Scheduled
Payment Date, or any other date specified for such purpose in the form of Bond
of such series attached to the Series Supplemental Indenture relating to the
Bonds of such series.

       "Regulation S" means Regulation S promulgated under the Securities Act,
as amended and in effect from time to time.

       "Related Person" has the meaning set forth in Section 17.1.

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<PAGE>   28

                                      -20-

       "Required Amount" means, at the time of determination with respect to the
Bonds of any series, all principal of and interest on such series projected to
be payable on the next Scheduled Payment Date for such series of Bonds.

       "Responsible Officer", when used with respect to the Trustee, means any
officer in the Corporate Trust Office (or any successor group of the Trustee)
including any vice president, assistant vice president, assistant secretary,
assistant treasurer or any other officer of the Trustee customarily performing
functions similar to those performed by the persons who at the time shall be
such officers, respectively, or to whom any corporate trust matter is referred
because of his knowledge and familiarity with the particular subject.

       "Restricted Payments" means (i) membership distributions by or
distributions in respect of any equity interest in the Issuer or any Guarantor
(in cash, securities, property or obligations) on, or (ii) any payments or
distributions on account of, payments of interest on or the setting apart of
money for a sinking or other analogous fund for, or the purchase, redemption,
retirement or other acquisition of, (a) Subordinated Indebtedness or (b) any
portion of any membership interest or equity interest in the Issuer or such
Guarantor or of any warrants, options or other rights to acquire any such
membership interest or equity interest (or to make any payments to any Person,
such as "phantom stock" payments, where the amount thereof is calculated with
reference to fair market or equity value of the Issuer or any Guarantor),
provided that distributions or other payments by a Guarantor to the Issuer will
not constitute Restricted Payments.

       "Revenues" means, with respect to the Issuer or any Guarantor, for any
period, the sum of: (i) all revenues of the Issuer or any Guarantor in respect
of its operations under any contract or agreement or otherwise including amounts
received pursuant to Hedging Agreements (other than Interest Rate Agreements).

       "S&P" means Standard & Poor's Ratings Group or any successor thereto.

       "Scheduled Payment Date" means, with respect to any Bond of a series or
any installment of principal thereof or payment of interest thereon, the date
specified in such Bond (or in the Series Supplemental Indenture relating to such
Series) as the fixed date on which such Bond or such installment of principal or
payment of interest is due and payable.

       "SEC" means the Securities and Exchange Commission of the United States.

       "Secured Parties" has the meaning given to such term in the Collateral
Agency and Intercreditor Agreement.

       "Securities Act" means the Securities Act of 1933, as amended and in
effect from time to time.

       "Security Agreement" means the Security Agreement dated as of February
22, 2000 among the Issuer, the Guarantors and the Trustee.

       "Security Register" has the meaning set forth in Section 2.8.

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<PAGE>   29

                                      -21-

       "Security Registrar" means any Person acting as Security Registrar
pursuant to Sections 2.8 and 11.11.

       "Senior Debt" means the Issuer's Indebtedness under the Bonds or any
other Indebtedness of the Issuer that ranks pari passu with the Bonds.

       "Series Supplemental Indenture" means any indenture supplemental to this
Indenture entered into by the Issuer, the Guarantors and the Trustee which
establishes, in accordance with this Indenture, the title, form and terms of the
Bonds of any series; and "Series Supplemental Indentures" means each and every
Series Supplemental Indenture.

       "Somerset Acquisition Documents" means the Asset Purchase Agreement
between NRG Energy and Montaup Electric Company dated as of October 13, 1998 and
each of the agreements attached as a form thereto.

       "Somerset Operator" means Somerset Operations Inc., a Delaware
corporation.

       "Somerset Power" means Somerset Power LLC, a Delaware limited liability
company.

       "Special Record Date" for the payment of any defaulted principal or
interest means a date fixed by the Trustee pursuant to Section 2.10.

       "Subordinated Indebtedness" means any Indebtedness of the Issuer that is
(a) payable solely and exclusively from the funds that would otherwise have been
available to make Restricted Payments from the Issuer or any Guarantor, (b)
fully subordinated in all rights and remedies to Senior Debt on terms
substantially similar to the subordination provisions set forth in Exhibit B and
(c) unsecured.

       "Subsequent Guarantor" means any Subsidiary of the Issuer, other than an
Initial Guarantor, that the Issuer designates as a Guarantor subsequent to the
Closing Date.

       "Subsidiary" means, with respect to any Person, (i) any corporation 50%
or more of whose stock of any class or classes having by the terms thereof
ordinary voting power to elect a majority of the directors of such corporation
(irrespective of whether or not at the time stock of any class or classes of
such corporation shall have or might have voting power by reason of the
happening of any contingency) is at the time owned by such Person, directly or
indirectly through Subsidiaries, and (ii) any partnership, limited liability
company, association, joint venture or other entity in which such Person,
directly or indirectly through Subsidiaries, has a 50% or greater equity
interest at the time.

       "Taxes" means, with respect any Person, any tax (whether income, gross
receipts, documentary, sales, stamp, registration, issue, capital, property,
excise or otherwise), duty, levy, impost, fee, charge or withholding directly or
indirectly imposed, assessed, levied or collected by or for the account of any
Governmental Authority.

       "Transaction Documents" means the Financing Documents, the Power Sales
Agreements, the Power Marketing Agreements, the Operation and Maintenance
Agreements, the

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<PAGE>   30
                                      -22-

Corporate Services Agreements, the Funds Administration Agreement and the
Assignment of Payments.

       "Transactions" means the execution, delivery and performance by each
Obligor of this Indenture and the other Transaction Documents to which such
Obligor is or is intended to be a party or by which it or its properties are
bound, the issuance of the Bonds and the use of the proceeds thereof as
described in Section 3.1.

       "Trust Indenture Act" means the Trust Indenture Act of 1939, as amended,
as in force at the date as of which this Indenture was executed (or, with
respect to any supplemental indenture, the date as of which such supplemental
indenture was executed).

       "Trustee" means the person named as the "Trustee" in the preamble to this
Indenture and its successors and assigns, and any corporation resulting from or
surviving any consolidation or merger to which it or its successors and assigns
may be a party, or any successor to all or substantially all of its corporate
trust business, provided that any such successor or assign or surviving
corporation shall be eligible for appointment as trustee pursuant to Section
11.7, until a successor Trustee must have become such pursuant to the applicable
provisions of this Indenture, and thereafter means such successor Trustee.

       "Uniform Commercial Code" or "UCC" means the Uniform Commercial Code as
in effect from time to time in the State of New York and any other jurisdiction
the laws of which control the creation or perfection of security interests under
the Collateral Documents.

       "United States" means the United States of America.

       "Unrestricted Subsidiary" means (i) any Subsidiary of the Issuer that is
designated by the Issuer's Board of Directors as an Unrestricted Subsidiary
pursuant to a Board Resolution; but only to the extent that such Subsidiary: (a)
has no Indebtedness or other liabilities or obligations other than Non-Recourse
Obligations; (b) is not party to any agreement, contract, arrangement or
understanding with the Issuer or any Guarantor unless the terms of any such
agreement, contract, arrangement or understanding are no less favorable to the
Issuer or such Guarantor than those that might be obtained at the time from
Persons who are not Affiliates of the Issuer; and (c) is a Person with respect
to which neither the Issuer nor any of the Guarantors has any direct or indirect
obligation (x) to subscribe for additional equity interests or (y) to maintain
or preserve such Person's financial condition or to cause such Person to achieve
any specified levels of operating results. Any such designation by the Issuer's
Board of Directors shall be evidenced to the Trustee by filing with the Trustee
a certified copy of the Board Resolution giving effect to such designation and
an Officers' Certificate certifying that such designation complied with the
foregoing conditions. If, at any time, any Unrestricted Subsidiary would fail to
meet the foregoing requirements as an Unrestricted Subsidiary, it shall
thereafter cease to be an Unrestricted Subsidiary for purposes of this
Indenture, and for all other purposes such Subsidiary will be deemed to be a
Guarantor and any Indebtedness of such Subsidiary shall be deemed to be incurred
by a Guarantor as of such date (and, if such Indebtedness is not permitted to be
incurred as of such date under Section 6.8 hereof, the Issuer shall be in
default of such Section). The Board of Directors of the Issuer may at any time
designate any Unrestricted Subsidiary to be a Guarantor; provided that such
designation shall be deemed to be an incurrence

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<PAGE>   31

                                      -23-

of Indebtedness by a Guarantor of any outstanding Indebtedness of such
Unrestricted Subsidiary and such designation shall only be permitted if (i) such
Indebtedness is permitted under Section 6.8 hereof, and (ii) no Default or Event
of Default would occur or be in existence following such designation.

       "Working Capital Agreement" means the credit agreement dated February
22, 2000 among the Issuer, as borrower, the Guarantors party thereto and the
Working Capital Banks.

       "Working Capital Banks" means Citibank, N.A. and The Chase Manhattan Bank
and any of their successors and permitted assigns, as lenders under the Working
Capital Facility.

       "Working Capital Facility" means the 364-day revolving credit facility
established pursuant to the Working Capital Agreement.

       SECTION 1.2  Compliance Certificates and Opinions.  Except as otherwise
expressly provided by this Indenture, upon any application or request by the
Issuer to the Trustee that the Trustee take any action under any provision of
this Indenture, the Issuer shall furnish to the Trustee an Officer's Certificate
stating that all conditions precedent, if any, provided for in this Indenture
relating to the proposed action have been complied with and, if so requested by
the Trustee, an Opinion of Counsel stating that in the opinion of such counsel
all such conditions precedent, if any, have been complied with, except that in
the case of any particular application or request as to which the furnishing of
documents is specifically required by any provision of this Indenture relating
to such particular application or request, no additional certificate or opinion
need be furnished.

       Every certificate or opinion with respect to compliance with a
condition or covenant provided for in this Indenture shall include:

       (a) a statement that each individual signing such certificate or opinion
   has read such covenant or condition;

       (b) a brief statement as to the nature and scope of the examination or
   investigation upon which the statements or opinions contained in such
   certificate or opinion are based;

       (c) a statement that, in the opinion of each such individual, such
   examination or investigation has been made as is necessary to enable such
   individual to express an informed opinion as to whether or not such covenant
   or condition has been complied with; and

       (d) a statement as to whether, in the opinion of each such individual,
   such condition or covenant has been complied with.

       With the delivery of this Indenture, the Issuer and the Guarantors are
   furnishing to the Trustee, and from time to time thereafter may furnish, an
   Officer's Certificate identifying and certifying the incumbency and specimen
   signatures of the Authorized Representatives. Until the Trustee receives a
   subsequent Officers' Certificate, the Trustee shall be entitled to
   conclusively rely on the last such Officers' Certificate delivered to it

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<PAGE>   32

                                      -24-

   for purposes of determining the Authorized Representatives of the Issuer and
   the Guarantors.

       SECTION 1.3  Form of Documents Delivered to Trustee.  In any case where
several matters are required to be certified by, or covered by an opinion of any
specified Person, it is not necessary that all such matters be certified by, or
covered by the opinion of, only one such Person, or that they be so certified by
only one document, but one such Person may certify or give an opinion with
respect to some matters and one or more other such Persons as to other matters,
and any such Person may certify or give an opinion as to such matters in one or
several documents.

       Any certificate of an officer of the Issuer may be based, insofar as it
relates to legal matters, upon a certificate or opinion of, or representations
by, counsel, unless such officer knows or has reason to believe that the
certificate or opinion or representations with respect to the matters upon which
such officer's certificate is based are erroneous or otherwise inaccurate. Any
such certificate or Opinion of Counsel may be based, insofar as it relates to
factual matters, upon a certificate of, or representations by, an Authorized
Representative of the Issuer stating that the information with respect to such
factual matters is in the possession of the Issuer, unless such counsel knows
that the certificate or representations with respect to such matters are
erroneous.

       Any Opinion of Counsel stated to be based on the opinion of other counsel
shall be accompanied by a copy of such other opinion.

       Where any Person is required to make, give or execute two or more
applications, requests, consents, certificates, statements, opinions or other
instruments under this Indenture, they may, but need not, be consolidated and
form one instrument.

       SECTION 1.4  Notices, Etc. to Trustee.  Any Act of Holders or other
document required or permitted by this Indenture shall be deemed to have been
made or given, as applicable, only if such notice is in writing and delivered
personally, or by registered or certified first-class United States mail with
postage prepaid and return receipt requested, or made, given or furnished in
writing by confirmed telecopy or facsimile transmission, or by prepaid courier
service to the appropriate party as set forth below:

       Trustee:  The Chase Manhattan Bank
                 Capital Markets Fiduciary Services
                 450 W. 33rd Street, 15th Floor
                 New York, New York 10001

                 Attention: Annette Marsula
                            International and Project
                            Finance Group

                 Telecopier No.: (212) 946-8177
                 Telephone No.:  (212) 946-7557

                       NRG Northeast Generating Indenture
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<PAGE>   33

                                      -25-

       Issuer:         NRG Northeast Generating LLC
                       1221 Nicollet Mall
                       Suite 700
                       Minneapolis, MN  55403-2445

                       Attention:  Investor Relations

                       Telecopier No.:  (612) 373-5430

       With Copies to: NRG Energy, Inc.
                       1221 Nicollet Mall
                       Suite 700
                       Minneapolis, MN  55403-2445

                       Attention:  General Counsel

                       Telecopier No.:  (612) 373-5392

Any party may change its address by giving notice of such change in the manner
set forth herein. Any notice given to a party by mail or by courier shall be
deemed delivered upon receipt thereof (unless the party refuses to accept
delivery, in which case the party shall be deemed to have accepted delivery upon
presentation). Any notice given to a party by telecopy or facsimile transmission
shall be deemed effective on the date it is actually sent to the intended
recipient by confirmed telecopy or facsimile transmission to the telecopier
number specified above.

       SECTION 1.5  Notices to Holders; Waiver.  Where this Indenture provides
for notice to Holders of any event, such notice shall be sufficiently given
(unless otherwise herein expressly provided) if in writing and mailed,
first-class postage prepaid, to each Holder, at its address as it appears in the
Security Register, not later than the latest date, if any, and not earlier than
the earliest date, if any, prescribed for the giving of such notice. Where this
Indenture provides for notice, such notice may be waived in writing by the
Person entitled to receive such notice, either before or after the event, and
such waiver shall be the equivalent of such notice. Waivers of notice by Holders
shall be filed with the Trustee, but such filing shall not be a condition
precedent to the validity of any action taken in reliance upon such waiver. In
any case where notice to Holders is given by mail, neither the failure to mail
such notice, nor any defect in any notice so mailed, to any particular Holder
shall affect the sufficiency of such notice with respect to other Holders, and
any notice that is mailed in the manner herein provided shall be conclusively
presumed to have been duly given.

       SECTION 1.6  Conflict with Trust Indenture Act.  If any provision hereof
limits, qualifies or conflicts with another provision hereof which is required
to be included in this Indenture by any of the provisions of the Trust Indenture
Act, such required provision shall control. If any provision of this Indenture
modifies or excludes any provision of the Trust Indenture Act that may be so
modified or excluded, the latter provision shall be deemed to apply to this
Indenture as so modified or to be excluded, as the case may be.

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                                      -26-

       SECTION 1.7  Effect of Headings and Table of Contents.  The Article and
Section headings herein and the Table of Contents are for convenience only and
shall not affect the construction hereof.

       SECTION 1.8  Successors and Assigns.  All covenants, agreements,
representations and warranties in this Indenture by the Trustee, the Issuer and
the Guarantors shall bind and, to the extent permitted hereby, shall inure to
the benefit of and be enforceable by their respective successors and assigns,
whether so expressed or not.

       SECTION 1.9  Severability Clause.  In case any provision in this
Indenture or in the Bonds shall be invalid, illegal or unenforceable, the
validity, legality and enforceability of the remaining provisions shall not in
any way be affected or impaired thereby.

       SECTION 1.10 Benefits of Indenture. Nothing in this Indenture or in the
Bonds, expressed or implied, shall give to any Person, other than the parties
hereto and their successors hereunder and the Holders of Bonds, any benefit or
any legal or equitable right, remedy or claim under this Indenture.

       SECTION 1.11  Governing Law.  THIS INDENTURE SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK APPLICABLE TO
AGREEMENTS MADE AND TO BE PERFORMED ENTIRELY WITHIN THE STATE OF NEW YORK,
WITHOUT REGARD TO PRINCIPLES OF CONFLICTS OF LAW THEREOF TO THE EXTENT THE
APPLICATION OF SUCH PRINCIPLES WOULD CAUSE THE APPLICATION OF THE LAWS OF ANY
OTHER JURISDICTION.

       SECTION 1.12  Legal Holidays.  In any case where the Redemption Date or
the Scheduled Payment Date of any Bond or of any installment of principal
thereof or payment of interest thereon, or any date on which any defaulted
interest is proposed to be paid, shall not be a Business Day, then
(notwithstanding any other provision of this Indenture or such Bond) payment of
interest and/or principal, and/or premium, if any, need not be made on such
date, but may be made on the next succeeding Business Day with the same force
and effect as if made on the Redemption Date or on the Scheduled Payment Date,
or on the date on which the defaulted interest is proposed to be paid, and,
except as provided in any Series Supplemental Indenture setting forth the terms
of such Bond, if such payment is timely made, no interest shall accrue for the
period from and after such Redemption Date or Scheduled Payment Date, or date
for the payment of defaulted interest, as the case may be, to the date of such
payment.

       SECTION 1.13 Execution in Counterparts. This instrument may be executed
in any number of counterparts, each of which when so executed shall be deemed to
be an original, but all such counterparts shall together constitute but one and
the same instrument.

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                                      -27-

                                    ARTICLE 2

                                    THE BONDS

       SECTION 2.1  Form of Bond to Be Established by Series Supplemental
Indenture. The Bonds of each series shall be substantially in the form (not
inconsistent with this Indenture, including Section 2.5 hereof) established in
the Series Supplemental Indenture relating to the Bonds of such series.

       SECTION 2.2 Form of Trustee's Authentication. The Trustee's certificate
of authentication on all Bonds shall be in substantially the following form:

       This Bond is one of the Bonds referred to in the within-mentioned
Indenture.

                           ----------------------------
                           as Trustee

                           By
                             --------------------------
                             Authorized Signatory

       SECTION 2.3  Amount; Issuable in Series.  The aggregate principal amount
of Bonds that may be authenticated and delivered under this Indenture is
unlimited, provided that this Section 2.3 shall not be deemed to in any way
supersede the restrictions set forth in Section 6.8.

       The Bonds may be issued in one or more series.  There shall be
established in one or more Series Supplemental Indentures, prior to the issuance
of Bonds of any series:

       (a) the title of the Bonds of such series (which shall distinguish the
   Bonds of such series from all other Bonds) and the form or forms of Bonds of
   such series;

       (b) any limit upon the aggregate principal amount of the Bonds of such
   series that may be authenticated and delivered under this Indenture (except
   for Bonds authenticated and delivered upon registration of transfer of, or in
   exchange for, or in lieu of, other Bonds of such series pursuant to Section
   2.7, 2.8, 2.9, 8.6 or 14.6 and except for Bonds that, pursuant to the last
   paragraph of Section 2.4 hereof, are deemed never to have been authenticated
   and delivered hereunder);

       (c) the date or dates on which the principal of the Bonds of such series
   is payable, the amounts of principal payable on such date or dates and the
   Regular Record Date for the determination of Holders to whom principal is
   payable; and the date or dates on or as of which the Bonds of such series
   shall be dated, if other than as provided in Section 2.13(a);

       (d) the rate or rates at which the Bonds of such series shall bear
   interest, or the method by which such rate or rates shall be determined, the
   date or dates from which such interest shall accrue, the interest payment
   dates on which such interest shall be payable and the Regular Record Date for
   the determination of Holders to whom interest

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   is payable; and the basis of computation of interest, if other than as
   provided in Section 2.13(b);

       (e) if other than as provided in Section 11.11, the place or places where
   (i) the principal of, premium, if any, and interest on Bonds of such series
   shall be payable, (ii) Bonds of such series may be surrendered for
   registration of transfer or exchange and (iii) notices and demands to or upon
   the Issuer in respect of the Bonds of such series and this Indenture may be
   served;

       (f) the price or prices at which, the period or periods within which and
   the terms and conditions upon which Bonds of such series may be redeemed, in
   whole or in part, at the option of the Issuer;

       (g) the obligation, if any, of the Issuer to redeem, purchase or repay
   Bonds of such series pursuant to any sinking fund or analogous provision or
   at the option of a Holder thereof and the price or prices at which and the
   periods or periods within which and the terms and conditions upon which Bonds
   of such series shall be redeemed, purchased or repaid, in whole or in part,
   pursuant to such obligations;

       (h) if other than in minimum denominations of $100,000 and any integral
   multiple of $1,000 in excess thereof, the denominations in which Bonds of
   such series shall be issuable;

       (i) the restrictions or limitations, if any, on the transfer or exchange
   of the Bonds of such series including, without limitation, with respect to
   Bonds to be sold outside of the United States pursuant to Regulation S or any
   other exemption from registration under the Securities Act;

       (j) the obligation, if any, of the Issuer to file a registration
   statement with respect to the Bonds of such series or to exchange the Bonds
   of such series for Bonds registered pursuant to the Securities Act;

       (k) any trustees, authenticating or paying agents, warrant agents,
   transfer agents or registrars with respect to the Bonds of such series, if
   other than as set forth herein; and

       (l) any other terms of such series (which terms shall not be inconsistent
   with the provisions of this Indenture).

       SECTION 2.4  Authentication and Delivery of Bonds.  Subject to Section
2.3, at any time and from time to time after the execution and delivery of this
Indenture, the Issuer may deliver Bonds of any series executed by the Issuer to
the Trustee for authentication, together with an Issuer Order for the
authentication and delivery of such Bonds, and the Trustee shall thereupon
authenticate and make available for delivery such Bonds in accordance with such
Issuer Order, without any further action by the Issuer. No Bond shall be secured
by or entitled to any benefit under this Indenture or be valid or obligatory for
any purpose unless there appears on such Bond a certificate of authentication,
in the form provided for herein, executed by the Trustee by the manual signature
of any Authorized Signatory, and such certificate upon any Bonds shall be
conclusive evidence, and the only evidence, that such Bond has been duly

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authenticated and delivered thereunder. In authenticating such Bonds and
accepting the additional responsibilities under this Indenture in relation to
such Bonds, the Trustee shall be entitled to receive, and (subject to Section
11.1) shall be fully protected in relying upon:

       (a)  an executed Series Supplemental Indenture with respect to the Bonds
   of such series;

       (b) an Officer's Certificate of the Issuer (i) certifying as to Board
   Resolutions of the Issuer by or pursuant to which the terms of the Bonds of
   such series were established, (ii) certifying that all conditions precedent
   under this Indenture to the Trustee's authentication and delivery of such
   Bonds have been complied with and (iii) certifying that the terms of the
   Bonds of such series are not inconsistent with the terms of this Indenture as
   then and theretofore supplemented;

       (c) an Opinion of Counsel to the effect that (i) the form or forms and
   the terms of such Bonds have been established by a Series Supplemental
   Indenture as permitted by Sections 2.1 and 2.3 in conformity with the
   provisions of this Indenture and (ii) the Bonds of such series, when
   authenticated and made available for delivery by the Trustee and issued by
   the Issuer in the manner and subject to any conditions specified in such
   Opinion of Counsel, will constitute legal, valid and binding obligations of
   the Issuer, enforceable against the Issuer in accordance with their terms,
   except as enforceability (A) may be limited by applicable bankruptcy,
   insolvency, reorganization, moratorium and other similar laws affecting the
   enforcement of creditors' rights and remedies generally and (B) is subject to
   general principles of equity (regardless of whether enforceability is
   considered in a proceeding in equity or at law); and

       (d) such other documents and evidence with respect to the Issuer as the
   Trustee may reasonably request.

       Prior to the authentication and delivery of a series of Bonds, the
Trustee shall also receive such other funds, accounts, documents, certificates,
instruments or opinions as may be required by the related Series Supplemental
Indenture.

       Notwithstanding the foregoing, if any Bond shall have been authenticated
and delivered hereunder but never issued or sold by the Issuer, and the Issuer
shall deliver such Bond to the Trustee for cancellation as provided in Section
2.12 together with a written statement (which need not comply with Section 1.2
and need not be accompanied by an Opinion of Counsel) stating that such Bond has
never been issued or sold by the Issuer, for all purposes of this Indenture such
Bond shall be deemed never to have been authenticated and delivered hereunder
and shall never have been or be entitled to the benefits hereof.

       SECTION 2.5  Form.  The Bonds of each series shall be in registered form
and may have such letters, numbers or other marks of identification and such
legends or endorsements printed, lithographed, engraved, typewritten or
photocopied thereon, as may be required to comply with the rules of any
securities exchange upon which the Bonds of any such series are to be listed (if
any) or to conform to any usage in respect thereof, or as may, consistently
herewith, be prescribed by the Board of Directors of the Issuer or by the
Authorized

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Representative executing such Bonds, such determination by said Authorized
Representative to be evidenced by its signing the Bonds.

       The Bonds may be issued in the form of (a) definitive Bonds or (b) one
or more Global Bonds. Bonds issued in definitive form shall be registered in the
name or names of such Persons and for the principal amounts as the Issuer may
request. Bonds issued in the form of a Global Bond shall be registered in the
name of the Registered Depositary or its nominee and shall represent the
beneficial interests of Persons purchasing the Bonds. In the event any of the
Bonds are issued in a transaction under Rule 144A of the Securities Act, any
such Person shall purchase such Bonds in transactions complying with Rule 144A
under the Securities Act. The Trustee, as custodian ("Custodian"), will act as
custodian of each Global Bond for the Registered Depositary or appoint a
sub-custodian to act in such capacity. So long as the Registered Depositary or
its nominee is the registered owner of the Global Bond, it shall be considered
the Holder of the Bonds represented thereby for all purposes hereunder and under
the Global Bond. None of the Issuer, the Trustee or any Paying Agent shall have
any responsibility or liability for any aspect of the records relating to or
payments made by the Registered Depositary on account of beneficial interests in
the Global Bond. Interests in the Global Bond shall be transferred on the
Registered Depositary's book-entry settlement system.

       Anything in this Section 2.5 to the contrary notwithstanding, the Initial
Bonds shall be issued in definitive form unless otherwise specified in the First
Series Supplemental Indenture.

       SECTION 2.6  Execution of Bonds.  The Bonds shall be executed on behalf
of the Issuer by one of its Authorized Representatives. The signature of any
such officers on the Bonds may be manual or facsimile.

       Bonds bearing the manual or facsimile signatures of individuals who were,
at the time such signatures were affixed, the proper officers of the Issuer
shall bind the Issuer, notwithstanding that such individuals or any of them have
ceased to hold such offices prior to the authentication and delivery of such
Bonds or did not hold such offices at the date of such Bonds.

       SECTION 2.7  Temporary Bonds.  Pending the preparation of definitive
Bonds of any series pursuant to Section 2.8, the Issuer may execute, and upon
Issuer Order the Trustee shall authenticate and make available for delivery,
temporary Bonds of such series that are printed, lithographed, typewritten,
photocopied or otherwise produced, in any denomination, substantially of the
tenor of the definitive Bonds in lieu of which they are issued and with such
appropriate insertions, omissions, substitutions and other variations as the
Authorized Representative executing such Bonds may determine, as evidenced by
their execution of such Bonds.

       If temporary Bonds of any series are issued, the Issuer will cause
definitive Bonds of such series to be prepared without unreasonable delay. After
the preparation of definitive Bonds of such series, the temporary Bonds of such
series shall be exchangeable for definitive Bonds of such series upon surrender
of the temporary Bonds of such series at the Place of Payment, without charge to
the Holder. Upon surrender for cancellation of any one or more temporary Bonds
of any series, the Issuer shall execute, and the Trustee shall authenticate and

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                                      -31-

make available for delivery, in exchange therefor, definitive Bonds of such
series of authorized denominations and of like tenor and aggregate principal
amount. Until so exchanged, such temporary Bonds of any series shall in all
respects be entitled to the same benefits under this Indenture as definitive
Bonds of such series.

       SECTION 2.8  Registration; Restrictions on Transfer and Exchange.  (a)
The Issuer shall cause to be kept at the Corporate Trust Office of the Security
Registrar a register which, subject to such reasonable regulations as the Issuer
may prescribe, shall provide for the registration of Bonds and for the
registration of transfers and exchanges of Bonds. This register and, if there
shall be more than one Security Registrar, the combined registers maintained by
all such Security Registrars, are herein sometimes referred to as the "Security
Register". The Trustee is hereby appointed the initial Security Registrar for
the purpose of registering Bonds and transfers and exchanges of Bonds as herein
provided. Upon any resignation or removal of the Security Registrar, the Issuer
shall promptly appoint a successor, or in the absence of such appointment,
assume the duties of such Security Registrar.

       If a Person other than the Trustee is appointed by the Issuer as
Security Registrar, the Issuer will give the Trustee prompt written notice of
the appointment of a Security Registrar and of the location, and any change in
the location of the Security Register, and the Trustee shall have the right to
inspect the Security Register at all reasonable times and to obtain copies
thereof, and the Trustee shall have the right to rely upon such Security
Register as to the names and addresses of the Holders of the Bonds and the
principal amounts and numbers of such Bonds.

       (b)  Any Global Bond shall be exchanged for definitive Bonds, without
coupons, and delivered to and registered in the name of Persons named by the
Registered Depositary, rather than to the nominee for the Registered Depositary,
if (i) the Issuer advises the Trustee in writing that the Registered Depositary
is no longer willing or able to discharge properly its responsibilities as
Registered Depositary with respect to the Bonds and the Issuer is unable to
appoint a qualified successor, or that the Registered Depositary has ceased to
be a clearing agency registered under the Exchange Act, (ii) the Issuer, at its
option, elects to terminate the book-entry system through the Registered
Depositary with respect to the Bonds and cause issuance of certificated Bonds or
(iii) after the occurrence and continuation of an Event of Default, beneficial
owners holding interests representing an aggregate principal amount of Bonds of
more than 50% of the Bonds represented by the Global Bond advise the Trustee
through the Registered Depositary in writing that the continuation of a
book-entry system through the Registered Depositary with respect to the Bonds is
no longer in such owners' best interests.

       Upon the occurrence of any of the events in clauses (i) through (iii)
of the preceding paragraph, the Trustee shall, by forwarding any notice received
from the Issuer to the Registered Depositary, be deemed to have notified all
Persons who hold a beneficial interest in the Global Bond through participants
in the Registered Depositary or indirect participants through participants in
the Registered Depositary of the availability of definitive Bonds. Upon
surrender by the Registered Depositary of the Global Bond and receipt of
instructions for re-registration, the Security Registrar will exchange the
Global Bond for an equal aggregate principal amount of definitive Bonds.

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       After the expiration of the Distribution Compliance Period pursuant to
Regulation S of the Securities Act applicable to such securities, at the option
of the Holder, beneficial interests in Global Bonds of any series may be
exchanged in whole or in part for certificated Bonds of the same series to be
registered in the name of such Holder, of authorized denominations and of like
tenor, maturity, interest rate and aggregate principal amount, upon prior
written notice to the Trustee by or on behalf of the Registered Depositary and
surrender of the Bonds to be exchanged at any office or agency maintained for
such purpose pursuant to Section 11.11. Whenever any Bonds are so surrendered
for exchange, the Issuer shall execute, and the Trustee shall authenticate and
make available for delivery, the Bonds which the Holder making the exchange is
entitled to receive. The Issuer shall execute and deliver to the Trustee, on the
Closing Date and from time to time thereafter, for safekeeping and subsequent
authentication, a stock of definitive registered Bonds of each series in such
quantities as the Issuer, after consultation with the Trustee, determines to be
sufficient to permit the issuance of definitive Bonds and the exchanges
contemplated by this Section.

       All Bonds issued upon any registration of transfer or exchange of Bonds
shall be the valid obligations of the Issuer, evidencing the same debt, and
entitled to the same security and benefits under this Indenture and the other
Collateral Documents, as the Bonds surrendered upon such registration of
transfer or exchange.

       Every Bond presented or surrendered for registration of transfer or
exchange shall be duly endorsed, or be accompanied by a written instrument of
transfer in form satisfactory to the Issuer and the Security Registrar or any
transfer agent, duly executed by the Holder thereof or such Holder's attorney
duly authorized in writing.

       No service charge shall be required of any Holders participating in any
transfer or exchange of Bonds in respect of such transfer or exchange, but the
Security Registrar may require payment of a sum sufficient to cover any Tax that
may be imposed in connection with any transfer or exchange of Bonds, other than
exchanges pursuant to section 2.7, 8.6 or 14.6 not involving any transfer.

       The Security Registrar shall not be required (a) to issue, register the
transfer of or exchange any Bond of any series during a period beginning at the
opening of business 15 days before the day of the mailing of a notice of
redemption of Bonds of such series selected for redemption under Section 8.2 and
ending at the close of business on the day of such mailing or (b) to issue,
register the transfer of or exchange any Bond so selected for redemption in
whole or in part, except the unredeemed portion of any Bond redeemed in part.

       SECTION 2.9  Mutilated, Destroyed, Lost and Stolen Bonds.  If (a) any
mutilated or defaced Bond is surrendered to the Trustee, or the Issuer and the
Security Registrar and the Trustee receive evidence to their satisfaction of the
destruction, loss or theft of any Bond, and (b) there is delivered to the
Issuer, the Security Registrar and the Trustee evidence to their satisfaction of
the ownership and authenticity thereof, and such security or indemnity as may be
required by them to save each of them harmless, then, in the absence of notice
to the Issuer, the Security Registrar or the Trustee that such Bond has been
acquired by a bona fide purchaser, the Issuer shall execute and upon the
Issuer's request the Trustee shall authenticate and make available for delivery,
in exchange for or in lieu of any such mutilated, destroyed, lost or stolen

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Bond, a new Bond of the same series and of like tenor, interest rate and
principal amount, bearing a number not then outstanding and registered in the
same manner. If, after the delivery of such new Bond, a bona fide purchaser of
the original Bond in lieu of which such new Bond was issued presents for payment
such original Bond, the Issuer and the Trustee shall be entitled to recover such
new Bond from the Person to whom it was delivered or any Person taking
therefrom, except a bona fide purchaser, and shall be entitled to recover upon
the security or indemnity provided therefor to the extent of any loss, damage,
cost or expenses incurred by the Issuer or the Trustee in connection therewith.

       Notwithstanding the foregoing, in case any such mutilated, destroyed,
lost or stolen Bond has become or is about to become due and payable, the
Issuer, upon satisfaction of the conditions set forth in clauses (a) and (b) of
the preceding paragraph may, instead of issuing a new Bond, pay such Bond.

       Upon the issuance of any new Bond under this Section 2.9, the Issuer may
require the payment of a sum sufficient to cover any Tax that may be imposed in
relation thereto and any other expenses connected therewith.

       Every new Bond issued pursuant to this Section 2.9 in lieu of any
mutilated, destroyed, lost or stolen Bond shall constitute an original
additional contractual obligation of the Issuer, whether or not the mutilated,
destroyed, lost or stolen Bond shall be at any time enforceable by anyone, and
shall be entitled to all the security and benefits of this Indenture and the
other Collateral Documents equally and proportionately with any and all other
Bonds duly issued hereunder.

       The provisions of this Section 2.9 are exclusive and shall preclude
(to the extent lawful) all other rights and remedies with respect to the
replacement or payment of mutilated, destroyed, lost or stolen Bonds.

       SECTION 2.10  Payment of Principal and Interest; Principal and Interest
Rights Preserved. Principal or interest on any Bond that is payable, and
punctually paid or duly provided for, on any Scheduled Payment Date shall be
paid to the Person in whose name that Bond (or one or more Predecessor Bonds) is
registered at the close of business on the Regular Record Date for such
principal or interest. Payment of principal of and interest on the Bonds of any
series shall be made at the Place of Payment (or, if such office is not in The
City of New York, at either such office or an office to be maintained in such
City), or by check or in another manner or manners if so provided in the Series
Supplemental Indenture relating to such series of Bonds, except for the final
installment of principal payable with respect to a Bond, which shall be payable
as provided in Section 8.5 (in the case of Bonds redeemed) or payable upon
presentation and surrender of such Bond at the Place of Payment.

       Any principal of or interest on any Bond of any series that is payable,
but is not punctually paid or duly provided for, on any Scheduled Payment Date
of an installment of principal or payment of interest shall forthwith cease to
be payable to the Holder on the relevant Regular Record Date and such defaulted
principal or interest may be paid by the Issuer, at its election in each case,
as provided in paragraph (a) or paragraph (b) below:

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       (a) The Issuer may elect to make payment of all or any portion of such
   defaulted principal or interest to the Persons in whose names the Bonds of
   such series (or their respective Predecessor Bonds) in respect of which
   principal or interest is in default are registered at the close of business
   on a Special Record Date for the payment of such defaulted principal or
   interest, which shall be fixed in the following manner. The Issuer shall
   notify the Trustee and the Paying Agent in writing of the amount of defaulted
   principal or interest proposed to be paid on each Bond of such series and the
   date of the proposed payment, and concurrently there shall be deposited with
   the Trustee an amount of money equal to the aggregate amount proposed to be
   paid in respect of such defaulted principal or interest or there shall be
   made arrangements acknowledged by the Trustee for such deposit prior to the
   date of the proposed payment, such money when deposited to be held in trust
   for the benefit of the Persons entitled to such defaulted principal or
   interest as provided in this paragraph. Thereupon, the Trustee shall fix a
   Special Record Date for the payment of such defaulted principal or interest
   (together with other amounts payable with respect to such defaulted principal
   or interest) which shall not be more than 15 nor less than 10 days prior to
   the date of the proposed payment and not less than 10 days after the receipt
   by the Trustee of the notice of the proposed payment. The Trustee shall
   promptly notify the Issuer and the Security Registrar of such Special Record
   Date and, in the name and at the expense of the Issuer, shall cause notice of
   the proposed payment of such defaulted principal or interest and the Special
   Record Date therefor to be mailed, first class postage prepaid, to each
   Holder of a Bond of such series at such Holder's address as it appears in the
   Security Register, not less than 10 days prior to such Special Record Date.
   Notice of the proposed payment of such defaulted principal or interest and
   the Special Record Date therefor having been mailed as aforesaid, such
   defaulted principal or interest shall be paid to the Persons in whose names
   the Bonds of such series (or their respective Predecessor Bonds) are
   registered on such Special Record Date and shall no longer be payable
   pursuant to the following paragraph (b).

       (b) The Issuer may make, or cause to be made, payment of any defaulted
   principal or interest (together with other amounts payable with respect to
   such defaulted interest) in any other lawful manner not inconsistent with the
   requirements of any securities exchange on which the Bonds in respect of
   which principal or interest is in default may be listed, and, upon such
   notice as may be required by such exchange, if, after notice given by the
   Issuer to the Trustee of the proposed payment pursuant to this paragraph,
   such payment shall be deemed reasonable by the Trustee.

       Subject to the foregoing provisions of this Section 2.10,
each Bond delivered under this Indenture upon registration of transfer of or in
exchange for or in lieu of any other Bond shall carry the rights to interest
accrued and unpaid, and to accrue, which were carried by such other Bond.

       SECTION 2.11  Persons Deemed Owners.  Subject to Section 2.10, prior to
due presentment of a Bond for registration of transfer, the Person in whose name
any Bond is registered shall be deemed to be the owner of such Bond for the
purpose of receiving payment of principal of, and premium, if any, and interest
on, such Bond and for all other purposes whatsoever, whether or not such Bond be
overdue, regardless of any notice to anyone to the contrary.

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       SECTION 2.12  Cancellation.  All Bonds surrendered for payment,
redemption, credit against any sinking fund payment or registration of transfer
or exchange or deemed lost or stolen shall, if surrendered to any Person other
than the Trustee, be delivered to the Trustee for cancellation and may not be
reissued or sold. The Issuer may at any time deliver to the Trustee for
cancellation any Bonds previously authenticated and delivered hereunder which
the Issuer may have acquired in any manner whatsoever. All Bonds so delivered
shall be promptly canceled by the Trustee. No Bonds shall be authenticated in
lieu of or in exchange for any Bonds canceled as provided in this Section,
except as expressly permitted by this Indenture. All canceled Bonds held by the
Trustee shall be either destroyed and certification of their destruction shall
be delivered to the Issuer or held by the Trustee in accordance with its
standard retention policy, unless the Issuer shall direct by an Issuer Order
that they be returned to it.

       SECTION 2.13  Dating of Bonds; Computation of Interest.  (a)  Except as
otherwise provided in the Series Supplemental Indenture relating to any series
of Bonds, each Bond of such series shall be dated the date of its
authentication.

       (b)  Except as otherwise provided in the Series Supplemental Indenture
relating to any series of Bonds, interest on the Bonds of such series shall be
computed on the basis of a 360-day year consisting of twelve 30-day months.

       SECTION 2.14  Source of Payments Limited; Rights and Liabilities of the
Issuer. All payments of principal and premium, if any, and interest to be made
in respect of the Bonds and this Indenture shall be made only from the payments
from the revenues of the Issuer and the Guarantors, the Collateral and the
income and proceeds received by the Trustee therefrom. Each Holder, by its
acceptance of a Bond, agrees that (a) it will look solely to the revenues of the
Issuer and the Guarantors, the Collateral and the income and proceeds received
by the Trustee therefrom to the extent available for distribution to such Holder
as herein provided or provided in the Collateral Documents, (b) none of the
Members, or any of their respective past, present or future members, partners,
officers, directors or shareholders or other related Persons, or the Trustee
shall be personally or otherwise liable to any Holder, nor shall any of the
Members, or any of their respective past, present or future members, partners,
officers, directors or shareholders or other related Persons, be personally or
otherwise liable to the Trustee, for any amounts payable under any Bond or for
any liability under this Indenture or any other Transaction Document, except as
provided therein, and (c) recourse shall be otherwise limited in accordance with
Section 17.1.

       SECTION 2.15  Allocation of Principal and Interest.  Except as otherwise
provided in Section 8.6, each payment of principal of and premium, if any, and
interest on each Bond shall be applied, first, to the payment of accrued but
unpaid interest on such Bond (as well as any interest on overdue principal or,
to the extent permitted by applicable Law, overdue interest) to the date of such
payment, second, to the payment of the principal amount of and premium, if any,
on such Bond then due (including any overdue installment of principal)
thereunder, and third, the balance, if any, to the payment of the principal
amount of such Bond remaining unpaid.

       SECTION 2.16  Parity of Bonds.  Except as otherwise provided in this
Indenture and the other Collateral Documents, all Bonds of a series issued and
outstanding hereunder rank

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on a parity with each other Bond of the same series, and with all Bonds of each
other series and each Bond of a series shall be secured equally and ratably by
this Indenture and the other Collateral Documents with each other Bond of the
same series and with all Bonds of each other series, without preference,
priority or distinction of any one thereof over any other by reason of
difference in time of issuance or otherwise, and each Bond of a series shall be
entitled to the same benefits and security in this Indenture and the other
Collateral Documents as each other Bond of the same series and with all Bonds of
each other series.

                                    ARTICLE 3

                             APPLICATION OF PROCEEDS
                               FROM SALE OF BONDS

       SECTION 3.1  Application of Proceeds from Sale of Bonds.  Promptly upon
receipt by the Issuer of the proceeds from the sale of the Initial Bonds, the
Issuer shall apply such proceeds (i) to repay existing Indebtedness of the
Issuer incurred to acquire certain Facilities, (ii) to pay costs, expenses and
the Initial Purchasers' discounts and commissions in connection with the
offering of the Initial Bonds and (iii) to repay NRG Energy money loaned in
connection with the purchase of the Facilities acquired from CL&P.

                                    ARTICLE 4

                          DEBT SERVICE RESERVE ACCOUNT

       SECTION 4.1  Debt Service Reserve Account.

       (a)  Creation of the Account.  The Issuer hereby establishes at the
Trustee's Corporate Trust Office a special, segregated and irrevocable,
non-interest bearing collateral account (the "Debt Service Reserve Account")
which shall be maintained at all times until the termination of this Indenture.
All amounts from time to time held in the Debt Service Reserve Account shall be
held in the name of the Trustee for the benefit of the Holders. Except as
expressly provided in this Indenture, neither the Issuer nor any Guarantor shall
have any right to withdraw funds from the Debt Service Reserve Account. All
amounts on deposit in the Debt Service Reserve Account and all Permitted
Investments held therein shall constitute a part of the Collateral and shall not
constitute payment of any Bonds until applied as provided in this Indenture. The
Issuer hereby irrevocably authorizes the Trustee to withdraw funds from the Debt
Service Reserve Account in accordance with this Section 4.1.

       (b)  Funding of the Account.  On the Closing Date, the Issuer shall
deposit cash, Permitted Investments, one or more Debt Service Reserve Support
Instruments or any combination thereof into the Debt Service Reserve Account and
shall at all times thereafter cause the amount on deposit therein (which may be
cash, Permitted Investments, Debt Service Reserve Support Instruments or any
combination thereof) to be at least equal to the Debt Service Reserve
Requirement.

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       (c)  Withdrawals from the Account.

       (i) The Issuer may direct the withdrawal of funds from the Debt Service
Reserve Account (A) to the extent that no other funds are available to it to pay
principal or interest on the Bonds of any series that are due on the date of
such withdrawal (each, a "Withdrawal Date") and (B) if on any Scheduled Payment
Date, the Trustee shall have received from the Issuer funds that are
insufficient to pay the aggregate amount of the principal and interest then due.
For each withdrawal from the Debt Service Reserve Account pursuant to this
Section 4.1(c), the Issuer shall deliver to the Trustee no less than two
Business Days prior to the relevant Withdrawal Date, a certificate (each, a
"Withdrawal Certificate") of an Authorized Representative stating that the funds
available to it to pay the aggregate amount of such principal and interest due
and payable on the Bonds on the Withdrawal Date are insufficient to pay such
amounts and setting out the relevant Withdrawal Date and the amount to be
withdrawn. On each Withdrawal Date, the Trustee shall transfer from the Debt
Service Reserve Account, to the extent funds are available therein, to the
accounts of the Holders the amount specified in the relevant Withdrawal
Certificate.

       (ii) If on any Scheduled Payment Date the Paying Agent shall have
received from or on behalf of the Issuer funds that are insufficient to pay the
aggregate amount of such principal and interest in full, then, upon notice
thereof by the Paying Agent to the Trustee specifying the amount of such
insufficiency, the Trustee shall transfer from the Debt Service Reserve Account,
to the extent funds are available therein, to the accounts of the Holders an
amount equal to such insufficiency.

       (iii) If on any date on or prior to the maturity date of the Bonds of any
series on which the Trustee is required to make withdrawals from the Debt
Service Reserve Account pursuant to the foregoing clauses (i) or (ii) the funds
on deposit in the Debt Service Reserve Account are insufficient to make such
withdrawals, the Trustee shall draw on or demand payment under any Debt Service
Reserve Support Instrument then in its possession and selected by the Trustee in
an amount equal, when added to all amounts paid under each other Debt Service
Reserve Support Instrument on such date, to such insufficiency.

       (iv) Unless the Trustee shall have been notified in writing that an Event
of Default shall have occurred and is continuing or would result therefrom, if
on the last Business Day of any calendar month, the credit balance of the Debt
Service Reserve Account exceeds the Debt Service Reserve Requirement, then upon
the written request of the Issuer delivered to the Trustee no less than two
Business Days prior to the such last Business Day, the Trustee shall transfer
from the Debt Service Reserve Account to the Issuer an amount equal to such
excess in accordance with the instructions specified therefor in such request.

       (d)  Debt Service Reserve Support Instruments.

       (i) At any time on or after the Closing Date, the Issuer may deliver to
the Trustee a Debt Service Reserve Support Instrument in an aggregate amount
available to be drawn

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       or demanded thereunder equal to all or a portion of the Debt Service
       Reserve Requirement. At any time upon or after delivery of a Debt
       Service Reserve Support Instrument, the Issuer may deliver to the
       Trustee a certificate (a "Reduction Certificate") setting out the
       Issuer's calculation of the excess of (x) the aggregate amount of cash
       and Permitted Investments on deposit in the Debt Service Reserve Account
       plus the aggregate amount then available to be drawn under all Debt
       Service Reserve Support Instruments theretofore delivered to the Trustee
       over (y) the Debt Service Reserve Requirement. The Trustee shall, in
       accordance with the instructions specified therefor in such request,
       within 2 Business Days of the receipt of a Reduction Certificate,
       transfer from the Debt Service Reserve Account to the Issuer cash or
       Permitted Investments or reduce the amount available to be drawn on or
       demanded under such Debt Service Reserve Support Instrument(s) in an
       amount equal to such excess.

            (ii) In the event that at any time prior to the termination or
       satisfaction and discharge of this Indenture the issuing financial
       institution in respect of any Debt Service Reserve Letter of Credit
       fails to qualify as an Acceptable Bank, the Issuer shall cause all Debt
       Service Reserve Letters of Credit issued by such issuing bank to be
       replaced by another Debt Service Reserve Support Instrument or cash
       deposit or Permitted Investment in an amount at least equal to the
       available face amount of the Debt Service Reserve Letter(s) of Credit
       being replaced. If such Debt Service Reserve Letter of Credit is not so
       replaced within thirty (30) days of notice by the Trustee to the Issuer
       of the failure of such issuing financial institution to qualify as an
       Acceptable Bank, then in each case, the Trustee shall draw on the full
       available face amount of such Debt Service Reserve Letter of Credit
       (less any excess of the aggregate cash, Permitted Investments and Debt
       Service Reserve Support Instruments over the Debt Service Reserve
       Requirement) in accordance with the terms thereof and deposit the
       proceeds of such draw into the Debt Service Reserve Account.

            (iii) In the event that at any time prior to the termination or
       satisfaction and discharge of this Indenture a guarantor under any Debt
       Service Reserve Guarantee fails to qualify as an Acceptable Guarantor,
       the Issuer shall cause the Debt Service Reserve Guarantee of such Person
       to be replaced by another Debt Service Reserve Support Instrument or
       cash deposit or Permitted Investment in an amount at least equal to the
       amount guaranteed under the Debt Service Reserve Guarantee being
       replaced. If such Debt Service Reserve Guarantee is not so replaced
       within thirty (30) days of notice by the Trustee to the Issuer of the
       failure of such Person to qualify as an Acceptable Guarantor, then in
       each case, the Trustee shall draw on the full amount guaranteed under
       such Debt Service Reserve Guarantee (less any excess of the aggregate
       cash, Permitted Investments and Debt Service Reserve Support Instruments
       over the Debt Service Reserve Requirement) in accordance with the terms
       thereof and deposit the proceeds of such draw into the Debt Service
       Reserve Account.

       (e)  The amount on deposit in the Debt Service Reserve Account at any
time shall be deemed to be equal to the aggregate amount of cash on deposit
therein at such time, plus the aggregate fair market value of all Permitted
Investments on deposit therein at such time, plus the amount available to be
drawn or demanded under all Debt Service Reserve Support Instruments held by the
Trustee at such time.

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       SECTION 4.2.  Securities Account; Securities Intermediary.

       Securities Intermediary.  (a) Acceptance of Appointment of Securities
Intermediary. The Chase Manhattan Bank hereby agrees to act as securities
intermediary as that term is defined in Section 8-102(a)(14) of the New York UCC
(in such capacity, the "Securities Intermediary") under this Indenture. Each of
the Issuer, the Guarantors, the Securities Intermediary and the Trustee hereby
acknowledges that the Securities Intermediary shall act as Securities
Intermediary under any Series Supplemental Indenture, unless otherwise
specified, as to any accounts established under such Series Supplemental
Indenture.

                  (b) Establishment of the Debt Service Reserve Account. The
Securities Intermediary hereby agrees and confirms that (A) the Securities
Intermediary has established the Debt Service Reserve Account, (B) the Debt
Service Reserve Account is and will be maintained as a "securities account"
(within the meaning of Section 8-501 of the UCC), (C) the Trustee is the
"entitlement holder" (within the meaning of Section 8-102(a)(7) of the UCC) in
respect of the "financial assets" (within the meaning of Section 8-102(a)(9) of
the UCC) credited to the Debt Service Reserve Account, (D) all property
delivered to the Securities Intermediary for deposit to the Debt Service Reserve
Account will be held by the Securities Intermediary and promptly credited to the
Debt Service Reserve Account by an appropriate entry in its records in
accordance with this Indenture, (E) all "financial assets" (within the meaning
of Section 8-102(a)(9) of the UCC) in registered form or payable to or to the
order and credited to the Debt Service Reserve Account shall be registered in
the name of, payable to or to the order of, or indorsed to, the Securities
Intermediary or in blank, or credited to another securities account maintained
in the name of the Securities Intermediary, and in no case will any financial
asset credited to the Debt Service Reserve Account be registered in the name of,
payable to or to the order of, or indorsed to, the Issuer or any Guarantor
except to the extent the foregoing have been subsequently indorsed by the Issuer
or such Guarantor to the Securities Intermediary or in blank, and (vi) the
Securities Intermediary shall not change the name or account number of the Debt
Service Reserve Account without the prior written consent of the Trustee.

                  (c) Financial Assets Election. The Securities Intermediary
agrees that each item of property (including any security, instrument or
obligation, share, participation, interest or other property whatsoever)
credited to the Debt Service Reserve Account shall be treated as a "financial
asset" within the meaning of Section 8-102(a)(9) of the UCC.

                  (d) Entitlement Orders, No Other Control Agreement, No Other
Liens. Each of the Issuer and each Guarantor agrees that the Securities
Intermediary may, and the Securities Intermediary agrees that it shall, comply
with any orders if originated by the Trustee without further consent by the
Issuer, any Guarantor or any other Person. In the event that the Securities
Intermediary receives conflicting entitlement orders from the Trustee and the
Issuer, any Guarantor or any other Person, the Securities Intermediary shall
comply with the entitlement orders originated by the Trustee. The Securities
Intermediary shall not execute and deliver, or otherwise become bound by, any
agreement under which the Securities Intermediary agrees with any Person other
than the Trustee to comply with entitlement orders originated by such Person
relating to the Debt Service Reserve Account or the security entitlements that
are the subject of this Indenture or any Series Supplemental Indenture. The
Securities Intermediary

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shall not grant any Lien in any financial asset that is the subject of any
security entitlement that is the subject of this Indenture or any Series
Supplemental Indenture.

                  (e) Subordination of Lien; Waiver of Setoff. In the event that
the Securities Intermediary has or subsequently obtains by indenture, operation
of law or otherwise a lien or security interest in the Debt Service Reserve
Account or any security entitlement credited thereto, the Securities
Intermediary agrees that such lien or security interest shall be subordinate to
the lien and security interest of the Trustee. The financial assets standing to
the credit of the Debt Service Reserve Account will not be subject to deduction,
setoff, banker's lien, or any other right in favor of any Person other than the
Trustee (except that the face amount of any checks which have been credited to
the Debt Service Reserve Account but are subsequently returned unpaid because of
uncollected or insufficient funds).

                  (f) No Other Agreements. None of the Securities Intermediary,
       the Trustee, the Issuer or any Guarantor has entered into any Agreement
       with respect to the Debt Service Reserve Account or any financial assets
       credited to the Debt Service Reserve Account other than this Indenture
       and the other Financing Documents. The Securities Intermediary has not
       entered into any agreement with the Issuer, the Guarantors or any other
       Person purporting to limit or condition the obligation of the Securities
       Intermediary to comply with entitlement orders originated by the Trustee
       in accordance with Section 4.2(d). In the event of any conflict as to
       such obligation between this Indenture and any other Transaction Document
       or any other agreement now existing or hereafter entered into, the terms
       of this Indenture shall prevail.

                  (g) Notice of Adverse Claims. Except for the claims and
interest of the Trustee, the Issuer and any Guarantor to and in the Debt Service
Reserve Account, the Securities Intermediary does not know of any claim to, or
interest in, the Debt Service Reserve Account or in any financial asset credited
thereto. If any Person asserts any lien, encumbrance or adverse claim (including
any writ, garnishment, judgment, warrant of attachment, execution or similar
process) against the Debt Service Reserve Account or in any financial asset
credited thereto, the Securities Intermediary will promptly notify the Trustee,
the Issuer and the Guarantors thereof.

                  (h) Rights and Powers of the Trustee. The rights and powers
granted by the Securities Intermediary to the Trustee have been granted in order
to perfect its lien and security interests in the Debt Service Reserve Account,
are powers coupled with an interest and will be affected by neither the
bankruptcy of the Issuer or any of the Guarantors nor the lapse of time.

                  (i) Choice of Law. Each Series Supplemental Indenture and the
Debt Service Reserve Account (including all security entitlements relating
thereto) shall be governed by the law of the State of New York. Regardless of
any provision in any Series Supplemental Indenture, for purposes of the UCC, the
"securities intermediary's jurisdiction" of the Securities Intermediary with
respect to the Debt Service Reserve Account is the State of New York.

       SECTION 4.3.  Security Interest.  As collateral security for the prompt
and complete payment and performance when due of the Bonds of any series, the
Issuer hereby

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pledges, assigns, hypothecates and transfers to the Trustee for the benefit of
the Trustee and the Holders, and hereby grants to the Trustee for the benefit of
the Trustee and the Holders, a lien on and security interest in and to (i) the
Debt Service Reserve Account and (ii) all property credited thereto, including,
but not limited to, cash, investments, securities and security entitlements at
any time on deposit in or credited to the Debt Service Reserve Account,
including all income or gain earned thereon and all security entitlements with
respect to any of the foregoing. The Debt Service Reserve Account shall at all
times be in the exclusive possession of and under the exclusive domain and
control of, the Trustee.

       SECTION 4.4  Investment of Funds.  Monies held in the Debt Service
Reserve Account created by or pursuant to this Indenture shall be invested and
reinvested in Permitted Investments at the written direction of an Authorized
Representative of the Issuer to the Trustee; provided, however, that the Trustee
shall not invest such monies at any time when the maturity of any of the Bonds
has been accelerated and provided, further, that at any time after the
occurrence and during the continuance of an Event of Default, the Trustee may,
but is not obligated to, (and, if instructed in writing by the Majority Holders
of all Bonds of all series as to which the Event of Default applies, shall) in
its (or their) discretion at any time and from time to time elect to liquidate
any such Permitted Investments (in an amount necessary to cure such Event of
Default) and apply or cause to be applied the proceeds thereof to the payment of
the Guaranteed Obligations in respect of principal of and interest on the Bonds
in the manner specified in Section 5.09 of the Security Agreement. Such
investments shall mature in such amounts and have maturity dates or be subject
to redemption at the option of the holder thereof on or prior to maturity as
needed for the purposes of such funds. Any profit realized from investments of
the Debt Service Reserve Account shall be deposited in the Debt Service Reserve
Account and any loss shall be charged to the Debt Service Reserve Account. In no
event shall the Trustee or the Securities Intermediary be liable for the
selection of Permitted Investments or for investment losses incurred thereon.
Neither the Trustee nor the Securities Intermediary shall have liability in
respect of losses incurred as a result of the liquidation of any Permitted
Investment prior to its stated maturity or the failure of the Issuer to provide
timely written investment direction, except to the extent such losses were due
to the gross negligence or bad faith on the part of the Trustee or the
Securities Intermediary. Neither the Trustee nor the Securities Intermediary
shall have any obligation to invest or reinvest any amounts held hereunder in
the absence of written investment direction.

                                    ARTICLE 5

                                 THE GUARANTEES

       SECTION 5.1 The Guarantees. The Guarantors hereby jointly and severally
guarantee to each Holder and the Trustee and their respective successors and
assigns the prompt payment in full when due (whether at stated maturity, by
acceleration or otherwise) of the principal of and interest on the Bonds and all
other amounts from time to time owing to the Holders or the Trustee by the
Issuer under this Indenture and any Series Supplemental Indenture and by any
Obligor under any of the other Financing Documents strictly in accordance with
the terms thereof (such obligations being herein collectively called the
"Guaranteed Obligations"). The Guarantors hereby further jointly and severally
agree that if the Issuer shall fail to pay in full

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                                      -42-

when due (whether at stated maturity, by acceleration or otherwise) any of the
Guaranteed Obligations, the Guarantors will promptly pay the same, without any
demand or notice whatsoever, and that in the case of any extension of time of
payment or renewal of any of the Guaranteed Obligations, the same will be
promptly paid in full when due (whether at extended maturity, by acceleration or
otherwise) in accordance with the terms of such extension or renewal.

       SECTION 5.2  Obligations Unconditional.  The obligations of the
Guarantors under Section 5.1 are absolute and unconditional, joint and several,
irrespective of the value, genuineness, validity, regularity or enforceability
of the obligations of the Issuer under this Indenture or any other agreement or
instrument referred to herein, or any substitution, release or exchange of any
other guarantee of or security for any of the Guaranteed Obligations, and, to
the fullest extent permitted by applicable law, irrespective of any other
circumstance whatsoever that might otherwise constitute a legal or equitable
discharge or defense of a surety or guarantor, it being the intent of this
Section that the obligations of the Guarantors hereunder shall be absolute and
unconditional, joint and several, under any and all circumstances. Without
limiting the generality of the foregoing, it is agreed that the occurrence of
any one or more of the following shall not alter or impair the liability of the
Guarantors hereunder, which shall remain absolute and unconditional as described
above:

       (i) at any time or from time to time, without notice to the Guarantors,
   the time for any performance of or compliance with any of the Guaranteed
   Obligations shall be extended, or such performance or compliance shall be
   waived;

       (ii) any of the acts mentioned in any of the provisions of this Indenture
   or any other agreement or instrument referred to herein shall be done or
   omitted;

       (iii) the maturity of any of the Guaranteed Obligations shall be
   accelerated, or any of the Guaranteed Obligations shall be modified,
   supplemented or amended in any respect, or any right under this Indenture or
   any other agreement or instrument referred to herein shall be waived or any
   other guarantee of any of the Guaranteed Obligations or any security therefor
   shall be released or exchanged in whole or in part or otherwise dealt with;
   or

       (iv) any lien or security interest granted to, or in favor of, the
   Trustee or any Holder or Holders as security for any of the Guaranteed
   Obligations shall fail to be perfected.

The Guarantors hereby expressly waive diligence, presentment, demand of payment,
protest and all notices whatsoever, and any requirement that the Trustee or any
Holder exhaust any right, power or remedy or proceed against the Issuer under
this Indenture or any other agreement or instrument referred to herein, or
against any other Person under any other guarantee of, or security for, any of
the Guaranteed Obligations.

       SECTION 5.3 Reinstatement. The obligations of the Guarantors under this
Article shall be automatically reinstated if and to the extent that for any
reason any payment by or on behalf of the Issuer in respect of the Guaranteed
Obligations is rescinded or must be

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otherwise restored by any holder of any of the Guaranteed Obligations, whether
as a result of any proceedings in bankruptcy or reorganization or otherwise, and
the Guarantors jointly and severally agree that they will indemnify the Trustee
and each Holder on demand for all reasonable costs and expenses (including
reasonable fees of counsel) incurred by the Trustee or such Holder in connection
with such rescission or restoration, including any such costs and expenses
incurred in defending against any claim alleging that such payment constituted a
preference, fraudulent transfer or similar payment under any bankruptcy,
insolvency or similar law.

       SECTION 5.4  Subrogation.  The Guarantors hereby jointly and severally
agree that, until the payment and satisfaction in full of all Guaranteed
Obligations and the satisfaction and discharge of the Bonds under this Indenture
and any Series Supplemental Indenture, they shall not exercise any right or
remedy arising by reason of any performance by them of their guarantees in
Section 5.1, whether by subrogation or otherwise, against the Issuer or any
other guarantor of any of the Guaranteed Obligations or any security for any of
the Guaranteed Obligations.

       SECTION 5.5  Remedies.  The Guarantors jointly and severally agree that,
as between the Guarantors and the Holders, the obligations of the Issuer under
this Indenture may be declared to be forthwith due and payable as provided in
Article 10 (and shall be deemed to have become automatically due and payable in
the circumstances provided in Article 10), for purposes of Section 5.1
notwithstanding any stay, injunction or other prohibition preventing such
declaration (or such obligations from becoming automatically due and payable) as
against the Issuer, and that, in the event of such declaration (or such
obligations being deemed to have become automatically due and payable), such
obligations (whether or not due and payable by the Issuer) shall forthwith
become due and payable by the Guarantors for purposes of Section 5.1.

       SECTION 5.6  Instrument for the Payment of Money.  Each Guarantor hereby
acknowledges that the guarantees in this Article constitute an instrument for
the payment of money, and consents and agrees that any Holder or the Trustee, at
its sole option, in the event of a dispute by such Guarantor in the payment of
any moneys due hereunder, shall have the right to bring motion-action under New
York CPLR Section 3213.

       SECTION 5.7  Continuing Guarantees.  The guarantees in this Article are
continuing guarantees and shall apply to all Guaranteed Obligations whenever
arising.

       SECTION 5.8  Rights of Contribution.  The Guarantors hereby agree, as
between themselves, that if any Guarantor shall become an Excess Funding
Guarantor (as defined below) by reason of the payment by such Guarantor of any
Guaranteed Obligations, each other Guarantor shall, on demand of such Excess
Funding Guarantor (but subject to the next sentence), pay to such Excess Funding
Guarantor an amount equal to such Guarantor's Pro Rata Share (as defined below
and determined, for this purpose, without reference to the properties, debts and
liabilities of such Excess Funding Guarantor) of the Excess Payment (as defined
below) in respect of such Guaranteed Obligations. The payment obligation of a
Guarantor to any Excess Funding Guarantor under this Section shall be
subordinate and subject in right of payment to the prior payment in full of the
obligations of such Guarantor under the other provisions of this

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Article, and such Excess Funding Guarantor shall not exercise any right or
remedy with respect to such excess until payment and satisfaction in full of all
of such obligations.

       For purposes of this Section, (i) "Excess Funding Guarantor" means, in
respect of any Guaranteed Obligations, a Guarantor that has paid an amount in
excess of its Pro Rata Share of such Guaranteed Obligations, (ii) "Excess
Payment" means, in respect of any Guaranteed Obligations, the amount paid by an
Excess Funding Guarantor in excess of its Pro Rata Share of such Guaranteed
Obligations and (iii) "Pro Rata Share" means, for any Guarantor, the amount
calculated by multiplying (A) all amounts due and payable in respect of the
Guaranteed Obligations times (B) the ratio of (x) the amount by which the
aggregate present fair saleable value of all assets of such Guarantor (excluding
any shares of stock of any other Guarantor) exceeds the amount of all the debts
and liabilities of such Guarantor (including contingent, subordinated, unmatured
and unliquidated liabilities, but excluding the obligations of such Guarantor
hereunder and any obligations of any other Guarantor that have been Guaranteed
by such Guarantor) to (y) the amount by which the aggregate fair saleable value
of all assets of all of the Guarantors exceeds the amount of all the debts and
liabilities (including contingent, subordinated, unmatured and unliquidated
liabilities, but excluding the obligations of the Issuer and the Guarantors
hereunder and under the other Transaction Documents) of all of the Guarantors,
determined (A) with respect to any Guarantor that is a party hereto on the
Effective Date, as of the Effective Date, and (B) with respect to any other
Guarantor, as of the date such Guarantor becomes a Guarantor hereunder.

       SECTION 5.9  General Limitation on Guarantee Obligations.  In any action
or proceeding involving any state corporate law, or any state or Federal
bankruptcy, insolvency, reorganization or other law affecting the rights of
creditors generally, if the obligations of any Guarantor under Section 5.1 would
otherwise, taking into account the provisions of Section 5.8, be held or
determined to be void, invalid or unenforceable, or subordinated to the claims
of any other creditors, on account of the amount of its liability under Section
5.1, then, notwithstanding any other provision hereof to the contrary, the
amount of such liability shall, without any further action by such Guarantor,
any Holder, the Trustee or any other Person, be automatically limited and
reduced to the highest amount that is valid and enforceable and not subordinated
to the claims of other creditors as determined in such action or proceeding.

       SECTION 5.10  Effectiveness.  The respective obligations of each
Guarantor under this Article 5 shall not be effective unless and until an
Authorized Representative of the Issuer shall have delivered a certificate
(each, a "Guarantee Effectiveness Certificate") to the Trustee to the effect
that all Governmental Approvals under Section 204 of the Federal Power Act as
may be necessary for such Guarantor to incur and perform its obligations under
this Article 5 have been obtained and remain in effect and that all applicable
waiting periods have expired without any action being taken by any competent
authority which restricts, prevents or imposes materially adverse conditions
upon the incurrence or performance of such obligations. The Issuer shall cause a
Guarantee Effectiveness Certificate in respect of each Guarantor to be delivered
to the Trustee within four Business Days after receipt by such Guarantor of such
Governmental Approvals and the expiration of such applicable waiting periods.

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                                    ARTICLE 6

                             COVENANTS OF THE ISSUER

       The Issuer hereby covenants and agrees that so long as this Indenture
is in effect and any Bonds remain Outstanding:

       SECTION 6.1  Financial Statements and Other Information.  For so long as
the Bonds are Outstanding, the Issuer will furnish to the Trustee and the Rating
Agencies:

       (a) within 105 days after the end of each fiscal year of the Issuer,
   (i) the audited consolidated balance sheet and related statements of
   operations, members' equity and cash flows of the Issuer and its Subsidiaries
   as of the end of and for such year and (ii) the audited consolidated balance
   sheet and related statements of operations, members' equity and cash flows of
   the Issuer and the Guarantors (excluding the financial condition and results
   of operations of the Issuer and the Unrestricted Subsidiaries) as of the end
   of and for such year, setting forth in each case in comparative form the
   figures for the previous fiscal year, all reported on by
   PricewaterhouseCoopers LLP or other independent public accountants of
   recognized national standing (without a "going concern" or like qualification
   or exception and without any qualification or exception as to the scope of
   such audit) to the effect that such consolidated financial statements present
   fairly in all material respects the financial condition and results of
   operations of the Issuer and its Subsidiaries on a consolidated basis in
   accordance with GAAP consistently applied;

       (b) within 60 days after the end of each of the first three quarters of
   each fiscal year of the Issuer, (i) the unaudited consolidated balance sheet
   and related statements of operations, members' equity and cash flows of the
   Issuer and its Subsidiaries as of the end of and for such fiscal quarter and
   the then-elapsed portion of the fiscal year and (ii) the unaudited
   consolidated balance sheet and related statements of operations, members'
   equity and cash flows of the Issuer and the Guarantors (excluding the
   financial condition and results of operations of the Issuer and the
   Unrestricted Subsidiaries), setting forth in each case in comparative form
   the figures for (or, in the case of the balance sheet, as of the end of) the
   corresponding period or periods of the previous fiscal year, all certified by
   an Authorized Representative of the Issuer as presenting fairly in all
   material respects the financial condition and results of operations of the
   Issuer and its Subsidiaries on a consolidated basis in accordance with GAAP
   consistently applied, subject to normal year-end audit adjustments and the
   absence of footnotes;

       (c) concurrently with any delivery of financial statements under clause
   (a) or (b) of this Section, an Officer's Certificate (i) certifying as to
   whether to the best knowledge of the signer thereof a Default has occurred
   and, if a Default has occurred, specifying the details thereof and any action
   taken or proposed to be taken with respect thereto, (ii) stating whether any
   change in GAAP or in the application thereof has occurred since the date of
   the most recent prior audited financial statements delivered pursuant to
   Section 6.1(a) or delivered to Holders on or prior to the Closing Date, as
   applicable, and, if any such change has occurred, specifying the effect of
   such change on the financial statements accompanying such certificate;

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       (d) concurrently with any delivery of financial statements under clause
   (a) of this Section, a certificate of the accounting firm that reported on
   such financial statements stating whether they obtained knowledge during the
   course of their examination of such financial statements of Defaults under
   clause (b) (B) (y) of the definition of "Permitted Investments" or clauses
   (b) or (c) of Section 6.15 (which certificate may be limited to the extent
   required by accounting rules or guidelines);

       (e) promptly after the same become publicly available, copies of all
   periodic and other reports, proxy statements and other materials filed by the
   Issuer or any of the Guarantors with the SEC, or any Governmental Authority
   succeeding to any or all of the functions of said commission, or with any
   national securities exchange, or distributed by the Issuer to its members
   generally, as the case may be;

       (f) promptly after receiving notice of the same, copies of  any
   information with respect to any material litigation or material governmental
   or environmental proceedings against the Issuer or the Guarantors; and

       (g) promptly following any request therefor, such other information
   regarding the operations, business affairs and financial condition of the
   Issuer or any of the Guarantors, or compliance with the terms of this
   Indenture and the other Transaction Documents, as the Trustee or Majority
   Holders may reasonably request.

       SECTION 6.2  Existence; Conduct of Business.  The Issuer will, and will
cause each of the Guarantors to, do or cause to be done all things necessary to
preserve, renew and keep in full force and effect its legal existence as a
limited liability company and all things reasonably necessary to preserve, renew
and keep in full force and effect the rights, licenses, permits, privileges and
franchises material to the conduct of its business as then conducted; provided
that the foregoing shall not prohibit any merger, consolidation, liquidation or
dissolution permitted under Section 6.14; provided, further, that the Issuer or
any Guarantor may change its status as a limited liability company if the Rating
Agencies confirm their current ratings of the Bonds and the Issuer or Guarantor,
as applicable, otherwise complies with its obligations under the Financing
Documents.

       SECTION 6.3  Maintenance of Tax Status.  The Issuer will not, and will
cause each of the Guarantors not to, voluntarily take any action to cause the
Issuer or any Guarantors to be subject to taxation as a separate entity for
federal income tax purposes.

       SECTION 6.4  Compliance with Laws and Contractual Obligations.  The
Issuer will, and will cause each of its Subsidiaries to, comply with all laws,
rules, regulations and orders of any Governmental Authority (including
Environmental Laws and ERISA matters), and all contractual obligations
applicable to it or its property, except where the failure to do so,
individually or in the aggregate, could not reasonably be expected to result in
a Material Adverse Effect.

       SECTION 6.5 Maintenance of Properties; Insurance.

       (a)  The Issuer will, and will cause each of the Guarantors to, (i) keep
and maintain all property material to the conduct of its business in good
working order and condition,

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ordinary wear and tear excepted; provided, however, that nothing in this Section
shall prevent the Issuer or a Guarantor from disposing of any asset (subject to
compliance with Section 6.12, 6.14, 7.6 or 7.11) or from discontinuing the
operation or maintenance of any of such material properties if such
discontinuance is, as determined by the Issuer in good faith, desirable in the
conduct of its business or the business of any Guarantor and would not
reasonably be expected to have a Material Adverse Effect on the Issuer and the
Guarantors taken as a whole and (ii) maintain, with financially sound and
reputable insurance companies, insurance with respect to each Facility in such
amounts and against such risks as are customarily maintained by companies
engaged in the same or similar businesses operating in the same or similar
locations. The Issuer will maintain and will cause the Guarantors to maintain
insurance for risks customarily insured against by other enterprises with
similar capital structures and owning and operating facilities of like size and
type as that of the Facilities in accordance with Prudent Industry Practice.

       (b)  The Issuer will (i) provide funds to each of the Guarantors at such
times and in such amounts so as to enable each of the Guarantors to pay all
Operating Expenses incurred by each such Guarantor on or before the date such
Operating Expenses become due and payable and (ii) cause each of the Guarantors
to comply with Section 7.7. If, on the last Business Day of each calendar month,
the funds available to the Issuer exceed the amount equal to the aggregate
amount of Operating Expenses of the Issuer and the Guarantors then due and
payable plus Operating Expenses of the Issuer and the Guarantors reasonably
anticipated to become due and payable during the following calendar month, then,
on or before the third Business Day of such following calendar month, the Issuer
shall deposit into the Debt Service Reserve Account an amount equal to the
lesser of (i) the Debt Service Reserve Shortfall, if any, determined as at the
last Business Day of a calendar month and (ii) the amount of such excess.

       SECTION 6.6  Payment of Taxes and Claims.  The Issuer will, and will
cause each of the Guarantors to, pay its obligations, including Tax liabilities,
before the same shall become delinquent or in default unless the same is then
the subject of a Good Faith Contest or except where nonpayment would not have a
Material Adverse Effect.

       SECTION 6.7  Books and Records; Inspection Rights.  The Issuer will, and
will cause each of the Guarantors to, keep proper books of record and account in
which full, true and correct entries are made of all dealings and transactions
in relation to its business and activities. The Issuer will, and will cause each
of the Guarantors to, permit the Trustee or its representative, upon reasonable
prior notice, to visit and inspect its properties, to examine and make extracts
from its books and records, and to discuss its affairs, finances and condition
with its officers and independent accountants, all at such reasonable times and
as often as reasonably requested.

       SECTION 6.8  Indebtedness.  The Issuer will not: (a) create, incur,
assume or permit to exist any Indebtedness, except Permitted Indebtedness; (b)
permit any Guarantor to create, incur, assume or permit to exist any
Indebtedness, except its guarantee of the Bonds or its guarantee of other
Permitted Indebtedness (other than Subordinated Indebtedness), and Intercompany
Loans; or (c) permit any Unrestricted Subsidiary to create, incur, assume or
permit to exist any Indebtedness, except Non-Recourse Obligations.

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       SECTION 6.9  Liens.  The Issuer will not, nor will it permit any of the
Guarantors to, create, incur, assume or permit to exist any Lien on any property
or asset now owned or hereafter acquired by it, or assign or sell any income or
revenues (including accounts receivable) or rights in respect of any thereof,
except Permitted Liens.

       SECTION 6.10  Certain Obligations Respecting Subsidiaries.

       (a)  Guarantors.  In the event that the Issuer shall form or acquire any
new subsidiary that shall constitute a Subsidiary hereunder, it shall designate
such new Subsidiary as a "Guarantor" or an "Unrestricted Subsidiary" and will
cause each new Subsidiary designated as a Guarantor:

       (i)  to become an "Obligor" under the Security Agreement;

       (ii) to take such action (including delivering such membership interests
   or other ownership interests, executing and delivering such Uniform
   Commercial Code financing statements) as shall be necessary to create and
   perfect valid and enforceable first priority Liens on substantially all of
   the personal property of such Guarantor on which a Lien is required to be
   created pursuant to the Security Agreement as collateral security for the
   obligations of such Guarantor hereunder; and

       (iii) to take such action, from time to time as shall be necessary to
   ensure that any such Guarantor remain at all times a "Guarantor" hereunder
   except as otherwise permitted hereunder (including Sections 6.12 and 6.14).

       (b)  Ownership of Subsidiaries.  The Issuer will, and will cause each of
its Subsidiaries to, take such action from time to time as shall be necessary to
ensure that the ownership of the Issuer in the voting equity interests of each
of its Subsidiaries (other than Unrestricted Subsidiaries) shall at all times
exceed 50% of all such voting equity interests. In the event that any additional
membership interests shall be issued by any Subsidiary (other than an
Unrestricted Subsidiary) to the Issuer, the Issuer agrees forthwith to deliver
to the Collateral Agent pursuant to the Security Agreement the certificates
evidencing such membership interests, accompanied by undated stock powers
executed in blank and to take such other action as the Trustee shall request to
perfect the security interest created therein pursuant to the Security
Agreement.

       SECTION 6.11  Restrictive Agreements.  The Issuer will not, and will not
permit any of the Guarantors to, directly or indirectly, enter into, incur or
permit to exist any agreement or other arrangement that prohibits, restricts or
imposes any condition upon (a) the ability of the Issuer or any Guarantor to
create, incur or permit to exist any Lien upon any of its property or assets
that is either (i) created under the Transaction Documents or (ii) in favor of
the Issuer, or (b) the ability of any Guarantor to pay dividends or other
distributions with respect to any shares of its capital stock or to make or
repay loans or advances to the Issuer or any other Guarantor or to Guarantee
Indebtedness of the Issuer or any other Guarantor except such prohibition,
restriction or condition existing under or by reason of: (1) applicable Law, (2)
this Indenture or any Financing Document, (3) with respect to real property,
customary non-assignment provisions of any contract or any lease governing a
leasehold interest of any Guarantor, (4) any agreements

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existing at the time of acquisition of any Person or the properties or assets of
the Person so acquired, which encumbrance or restriction is not applicable to
any Person, or the properties or assets of any Person, other than the Person or
the properties or assets of the Person so acquired, (5) agreements listed on
Schedule B hereof, (6) Liens incurred in accordance with Section 6.9 or 7.5 or
(7) refinancing of indebtedness with respect to clauses (4) or (5).

       SECTION 6.12  Prohibition on Sale of Assets.  The Issuer will not, and
will not, permit the Guarantors to, sell or otherwise dispose of any assets
other than (i) transfers of assets among the Issuer and the Guarantors; (ii)
sales and dispositions in the ordinary course of business not in excess of
$20,000,000 in the aggregate for the Issuer and the Guarantors in any fiscal
year; (iii) any sales or dispositions of surplus, obsolete or worn-out
equipment; (iv) any sales or dispositions required for compliance with
applicable Law or necessary Governmental Approvals; (v) sales or dispositions of
non-controlling ownership interests in Guarantors in accordance with Section
6.10(b) so long as the guarantee set forth herein with regard to such Guarantor
stays in effect; (vi) sales or dispositions of ownership interests in
Unrestricted Subsidiaries; (vii) any sales or dispositions of assets permitted
under Section 6.14 or 7.11; and (viii) any other sale or other disposition so
long as after giving effect to such events, the Rating Agencies shall have
confirmed their respective ratings of the Bonds in effect immediately prior to
such sale or other disposition.

       SECTION 6.13  Modifications of Certain Documents.  Without the prior
consent of the Majority Holders, the Issuer will not agree or consent to nor
allow any Guarantor to agree or consent to any termination, modification,
supplement, replacement or waiver of any Transaction Document, unless such
termination, modification, supplement, replacement or waiver could not,
individually or collectively with all other such terminations, modifications,
supplements, replacements and waivers, reasonably be expected to have a Material
Adverse Effect.

       SECTION 6.14 Prohibition on Fundamental Changes.

       (a)  Mergers, Consolidations, Disposal of Assets, Etc.  Except as
permitted under Section 6.12 (other than clause (vii) thereof) or Section 7.11
(other than clause (v) thereof), the Issuer will not, nor will it permit any of
the Guarantors to, merge into or consolidate with any other Person, or permit
any other Person to merge into or consolidate with it, or sell, transfer, lease
or otherwise dispose of (in one transaction or in a series of transactions) all
or any substantial part of its assets, or all or substantially all of the
membership or other equity interests of any of its Subsidiaries (in each case,
whether now owned or hereafter acquired), or liquidate or dissolve, except that,
if as a result thereof no Default shall have occurred and be continuing, (i) any
Subsidiary may merge into the Issuer in a transaction in which the Issuer is the
surviving corporation, (ii) any Guarantor may merge into any Guarantor in a
transaction in which the surviving entity is a Guarantor and the Issuer's
economic interest in each merging Guarantor's assets shall not have been
diminished as a result of such merger, (iii) any Guarantor may sell, transfer,
lease or otherwise dispose of its assets to the Issuer or to another Guarantor
(provided that the Issuer's economic interest in such assets is not diminished
as a result thereof) and (iv) any Guarantor may liquidate or dissolve if the
assets of such Guarantor are transferred to another Guarantor (provided that the
Issuer's economic interest in such assets is not diminished

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                                      -50-

as a result thereof and the Issuer determines in good faith that such
liquidation or dissolution is in the best interests of the Issuer and is not
materially disadvantageous to the Holders).

       (b) Lines of Business. The Issuer will not, nor will it permit any of
the Guarantors to, engage to any material extent in any business other than, (i)
in the case of the Issuer, the ownership of the Guarantors and the Unrestricted
Subsidiaries and the ownership and operation of non-nuclear electric generating
facilities and (ii) in the case of the Guarantors (including any Subsequent
Guarantors), the ownership and operation of their respective Facilities and the
ownership and operation of other non-nuclear electric generating facilities.

       SECTION 6.15  Restricted Payments.  The Issuer will not make, or agree to
pay or make, directly or indirectly, any Restricted Payment, unless, at the time
of and after giving effect to such Restricted Payment (a) no Default or Event of
Default shall have occurred and be continuing or would occur as a consequence of
such Restricted Payment; (b) the Debt Service Reserve Account is funded up to
the Debt Service Reserve Requirement; (c) the Debt Service Coverage Ratio for
the preceding four consecutive quarters (or such shorter period covering the
quarters ended subsequent to the issuance of the Bonds, taken as a consecutive
period) was not less than 1.50 to 1.0 in the case of any such period ending
prior to December 31, 2003 or 1.70 to 1.0 for any such period ending thereafter;
(d) the Projected Debt Service Coverage Ratio for the next succeeding eight
calendar quarters (taken as two periods of four quarters and determined as of
the beginning of the quarter during which the determination is made) is not less
than 1.50 to 1.0 in the case of any such four quarter period ending prior to
December 31, 2003 or 1.70 to 1.0 for any such four quarter period ending
thereafter; and (e) the Issuer certifies that making the Restricted Payment
would not reasonably be expected to have a Material Adverse Effect on the Issuer
and the Guarantors taken as a whole. Restricted Payments by any Guarantor of the
Issuer that is not a wholly-owned Subsidiary of the Issuer made otherwise than
to the Issuer shall be subject to the restrictions set forth in clauses (a), (b)
(c), (d) and (e) of the preceding sentence. Restricted Payments to the Issuer by
any wholly-owned Subsidiary of the Issuer shall not be subject to any
restrictions.

   Notwithstanding the foregoing, the Issuer will not be restricted from (i)
making payments to NRG Energy of any proceeds from treasury locks entered
into by the Issuer on or prior to the Closing Date and (ii) the repayment on the
date hereof of loans made by NRG Energy in connection with the Facilities
located in Connecticut and assumed by the Issuer.

       SECTION 6.16  Transactions with Affiliates.  The Issuer will not, nor
will it permit any of the Guarantors to, sell, lease or otherwise transfer any
property or assets to, or purchase, lease or otherwise acquire any property or
assets from, or otherwise engage in any other transactions with, any of its
Affiliates, except (a) transactions in the ordinary course of business at prices
and on terms and conditions not less favorable to the Issuer or such Subsidiary
than could be obtained on an arm's-length basis from unrelated third parties,
(b) transactions between or among the Issuer and the Guarantors not involving
any other Affiliate, (c) any Restricted Payment permitted by Section 6.15 or
7.7, and (d) transactions that are contemplated by any Transaction Document or
any extensions, renewals or replacements thereof that will not have a Material
Adverse Effect.

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       Notwithstanding the foregoing, the restrictions set forth in this
covenant shall not apply to (i) reasonable and customary directors' fees,
indemnification and similar arrangements, consulting fees, employee salaries,
bonuses or employment agreements, compensation or employee benefit arrangements
and incentive arrangements with any officer, director or employee of the Issuer
or any Subsidiary entered into in the ordinary course of business, (ii) loans
and advances to officers, directors and employees of the Issuer or any
Subsidiary for reasonable travel, entertainment, moving and other relocation
expenses, in each case made in the ordinary course of business, (iii) the
incurrence of intercompany Indebtedness which constitutes Permitted
Indebtedness, (iv) transactions pursuant to agreements in effect on the date
hereof, (v) the repayment to NRG Energy of funds money loaned by NRG Energy in
connection with the transactions contemplated by the CL&P Acquisition Documents
and (vi) the distribution to NRG Energy of any proceeds received by the Issuer
in connection with any treasury locks entered into on or before the Closing
Date.

       SECTION 6.17  Investments.  The Issuer will not, nor will it permit any
of the Guarantors to, make or permit to remain outstanding any Investments
except:

       (a) Investments outstanding on the date hereof and identified on Schedule
C;

       (b) operating deposit accounts with banks;

       (c) cash or Permitted Investments;

       (d) Investments by the Issuer or the Guarantors in the Issuer or the
Guarantors (including Investments by the Issuer in Intercompany Loans);

       (e) Investments in another Person, if as a result of such Investment (A)
such other Person becomes a Guarantor or (B) such other Person is merged or
consolidated with or into, or transfers or conveys all or substantially all of
its assets to the Issuer or a Guarantor;

       (f) Investments representing capital stock or obligations issued to, the
Issuer or any Guarantor in settlement of claims against any other Person by
reason of a composition or readjustment of debt or a reorganization of any
debtor of the Issuer or any Guarantor;

       (g)  Investments in the Bonds;

       (h) Investments acquired by the Issuer or any of the Guarantors in
connection with any asset sale permitted under Section 6.12, 6.14(a), 7.6(a) or
7.11 to the extent such Investments are non-cash proceeds as permitted under
Section 6.12, 6.14(a), 7.6(a) or 7.11;

       (i) any Investment to the extent that the consideration therefor is
capital stock (other than redeemable capital stock) of the Issuer;

       (j) Investments consisting of security deposits with utilities and other
Persons made in the ordinary course of business;

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       (k) Hedging Agreements entered into in the ordinary course of business
   and not for speculative purposes;

       (l) amounts constituting Restricted Payments which the Issuer would be
   permitted to make under Section 6.15 and the Guarantors would be permitted to
   make under Section 7.7; and

       (m) additional Investments up to but not exceeding $10,000,000 in the
   aggregate.

For purposes of clause (m) of this Section, the aggregate amount of an
Investment at any time shall be deemed to be equal to (A) the aggregate amount
of cash, together with the aggregate fair market value of property, including
any securities, loaned, advanced, contributed, transferred or otherwise invested
that gives rise to such Investment minus (B) the aggregate amount of dividends,
distributions or other payments received in cash in respect of such Investment;
the amount of an Investment shall not in any event be reduced by reason of any
write-off of such Investment nor increased by any increase in the amount of
earnings retained in the Person in which such Investment is made that have not
been dividend, distributed or otherwise paid out.

       SECTION 6.18 EWG Status. The Issuer will take, or cause to be taken, all
action required to maintain the Guarantors' status as "exempt wholesale
generators" under Section 32(a) of PUHCA.

       SECTION 6.19 Debt Service Reserve Account. The Issuer will maintain the
Debt Service Reserve Account in accordance with Article 4 at all times until the
termination of this Indenture.

       SECTION 6.20 Rule 144A Information.

       (a) Unless a registration statement shall have previously become
effective with respect to the Bonds, at any time when the Issuer is not subject
to Section 13 or 15(d) of the Exchange Act, upon the request of a Holder, the
Issuer shall promptly furnish to such Holder or to a prospective purchaser of
such Bond designated by such Holder, as the case may be, the information
required to be delivered pursuant to Rule 144A(d)(4) under the Securities Act in
order to permit compliance by such Holder with Rule 144A in connection with the
resale of such Bond by such Holder.

       (b) At any time after a registration statement with respect to the Bonds
shall have been filed with and declared effective by the SEC, the Issuer shall
provide to the such periodic and other reports that the Issuer is required to
file pursuant to Sections 13 or 15(d) of the Exchange Act.

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                                    ARTICLE 7

                           COVENANTS OF THE GUARANTORS

                     Each Guarantor hereby covenants and agrees that so long as
this Indenture is in effect and any Bonds remain Outstanding:

       SECTION 7.1 Existence; Conduct of Business. Each Guarantor agrees that it
will do or cause to be done all things necessary to preserve, renew and keep in
full force and effect such Guarantor's legal existence as a limited liability
company and all things reasonably necessary to preserve, renew and keep in full
force and effect such Guarantor's rights, licenses, permits, privileges and
franchises material to the conduct of such Guarantor's business as then
conducted; provided that the foregoing shall not prohibit any merger,
consolidation, liquidation or dissolution permitted under Section 7.6; provided,
further, that any Guarantor may change its status as a limited liability company
if the Rating Agencies confirm their then current ratings of the Bonds and such
Guarantor otherwise complies with its obligations under the Financing Documents.

       SECTION 7.2 Compliance with Laws and Contractual Obligations. Each
Guarantor agrees that it will comply with all Laws (including Environmental Laws
and ERISA matters) and all contractual obligations, in each case, as applicable
to such Guarantor or its property, except where the failure to do so,
individually or in the aggregate, would not reasonably be expected to result in
a Material Adverse Effect.

       SECTION 7.3 Maintenance of Properties; Insurance. Each Guarantor agrees
that it will (i) keep and maintain all property material to the conduct of such
Guarantor's business in good working order and condition, ordinary wear and tear
excepted; provided, however, that nothing in this Section shall prevent any
Guarantor from disposing of any asset (subject to compliance with Section 7.6 or
Section 7.11) or from discontinuing the operation or maintenance of any of such
material properties if the Guarantor reasonably determines in good faith that
such discontinuance is desirable in the conduct of its business and would not
reasonably be expected to have a Material Adverse Effect, and (ii) maintain,
with financially sound and reputable insurance companies, insurance with respect
to each Facility in such amounts and against such risks as are customarily
maintained by companies engaged in the same or similar businesses operating in
the same or similar locations in accordance with Prudent Industry Practices.
Each Guarantor agrees that it will maintain insurance for risks customarily
insured against by other enterprises with similar capital structures and owning
and operating facilities of like size and type as that of the Facilities in
accordance with Prudent Industry Practice.

       SECTION 7.4 Indebtedness. Each Guarantor agrees that it will not create,
incur, assume or permit to exist any Indebtedness, except Intercompany Loans,
the Guarantees of the Bonds or guarantees of other Permitted Indebtedness (other
than Subordinated Indebtedness).

       SECTION 7.5 Liens. Each Guarantor agrees that it will not create, incur,
assume or permit to exist any Lien on any property or asset now owned or
hereafter acquired by such Guarantor, or assign or sell any income or revenues
(including accounts receivable) or rights in respect of any thereof, except
Permitted Liens.

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       SECTION 7.6 Prohibition on Fundamental Changes.

       (a) Mergers, Consolidations, Disposal of Assets, Etc. Except as permitted
by Section 6.12 (other than clause (vii) thereof) or Section 7.11 (other than
clause (v) thereof), each Guarantor agrees that it will not merge into or
consolidate with any other Person, or permit any other Person to merge into or
consolidate with such Guarantor, or sell, transfer, lease or otherwise dispose
of (in one transaction or in a series of transactions) all or any substantial
part of its assets (in each case, whether now owned or hereafter acquired), or
liquidate or dissolve, except that (i) each Guarantor may merge into a
Subsidiary in a transaction in which such Guarantor is the surviving
corporation, (ii) any Guarantor may merge into any other Guarantor in a
transaction in which the surviving entity is a Guarantor, (iii) each Guarantor
may sell, transfer, lease or otherwise dispose of such Guarantor's assets to the
Issuer or to any other Guarantor and (iv) any Guarantor may liquidate or
dissolve if the Issuer determines in good faith that such liquidation or
dissolution is in the best interests of the Guarantor and is not materially
disadvantageous to the Holders, provided that no Default shall have occurred and
be continuing as a result of any of the events described in clauses (i), (ii) or
(iii) above.

       (b) Lines of Business. Each Guarantor agrees that it will not engage to
any material extent in any business other than the ownership and operation of
such Guarantor's respective Facilities or other non-nuclear electric generating
facilities, provided that each Subsequent Guarantor agrees that it will not
engage to any material extent in any business other than the ownership and
operation of non-nuclear electric generating facilities.

       SECTION 7.7 Restricted Payments. Each Guarantor agrees that it will not
make, or agree to pay or make, directly or indirectly, any Restricted Payment,
unless such payment is only (a) to the Issuer at any time or (b) to any future
minority owners of the Guarantors only if at the time of such Restricted Payment
the Issuer would itself be permitted to make the payment to such other minority
owner as if such minority owner held a minority interest in the Issuer instead
of such Guarantor.

       SECTION 7.8 Transactions with Affiliates. Each Guarantor agrees that it
will not sell, lease or otherwise transfer any property or assets to, or
purchase, lease or otherwise acquire any property or assets from, or otherwise
engage in any other transactions with, any of such Guarantor's Affiliates,
except (a) transactions in the ordinary course of business at prices and on
terms and conditions not less favorable to the Guarantor than could be obtained
on an arm's-length basis from unrelated third parties, (b) transactions between
or among such Guarantor and the Issuer or any of the other Guarantors not
involving any other Affiliate, (c) any Restricted Payment permitted by Section
6.15 or 7.7 and (d) transactions that are contemplated by any Transaction
Document or any extensions, renewals or replacements thereof, if any such
transaction would not reasonably be expected to result in a Material Adverse
Effect.

       Notwithstanding the foregoing, the restrictions set forth in this
covenant shall not apply to (i) reasonable and customary directors' fees,
indemnification and similar arrangements, consulting fees, employee salaries,
bonuses or employment agreements, compensation or employee benefit arrangements
and incentive arrangements with any officer, director or employee of the Issuer
or any Subsidiary entered into in the ordinary course of business, (ii) loans
and advances to officers, directors and employees of the Issuer or any
Subsidiary for

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                                      -55-

reasonable travel, entertainment, moving and other relocation expenses, in each
case made in the ordinary course of business, (iii) the incurrence of
intercompany Indebtedness which constitutes Permitted Indebtedness and (iv)
transactions pursuant to agreements in effect on the date hereof.

       SECTION 7.9 Investments. Each Guarantor agrees that it will not make or
permit to remain outstanding any Investments except:

       (a) Investments outstanding on the date hereof and identified in Schedule
   C;

       (b) operating deposit accounts with banks;

       (c) cash or Permitted Investments;

       (d) Investments by such Guarantor in the Issuer or other Guarantors;

       (e) Investments in another Person, if as a result of such Investment (A)
   such other Person becomes a Guarantor or (B) such other Person is merged or
   consolidated with or into, or transfers or conveys all or substantially all
   of its assets to the Issuer or a Guarantor;

       (f) Investments representing capital stock or obligations issued to, the
   Issuer or any Guarantor in settlement of claims against any other Person by
   reason of a composition or readjustment of debt or a reorganization of any
   debtor of the Issuer or any Guarantor;

       (g) Investments in the Bonds;

       (h) Investments acquired by any Guarantor in connection with any asset
   sale permitted under Section 6.12, 6.14, 7.6(a) or 7.11 to the extent such
   Investments are non-cash proceeds as permitted under Section 6.12, 6.14(a),
   7.6(a) or 7.11;

       (i) any Investment to the extent that the consideration therefor is
   capital stock (other than redeemable capital stock) of the Issuer;

       (j) Investments consisting of security deposits with utilities and other
   like Persons made in the ordinary course of business;

       (k) Hedging Agreements entered into in the ordinary course of business
   and not for speculative purposes;

       (l) amounts constituting Restricted Payments which the Guarantor would
   otherwise be permitted to make to minority owners under Section 7.7; and

       (m) additional Investments up to but not exceeding $10,000,000 in the
   aggregate with respect to such Guarantor, the other Guarantors and the
   Issuer.

For purposes of clause (m) of this Section, the aggregate amount of an
Investment at any time shall be deemed to be equal to (A) the aggregate amount
of cash, together with the aggregate fair

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market value of property, including any securities, loaned, advanced,
contributed, transferred or otherwise invested that gives rise to such
Investment minus (B) the aggregate amount of dividends, distributions or other
payments received in cash in respect of such Investment; the amount of an
Investment shall not in any event be reduced by reason of any write-off of such
Investment nor increased by any increase in the amount of earnings retained in
the Person in which such Investment is made that have not been dividend,
distributed or otherwise paid out.

       SECTION 7.10 Operation of Facilities. Each Guarantor agrees that it will
operate or cause its respective Facility to be operated in accordance with
Prudent Industry Practices.

       SECTION 7.11 Prohibition on Sale of Assets. Each Guarantor agrees not to
sell or otherwise dispose of any assets other than (i) transfers of assets
between the Issuer and such Guarantor; (ii) sales and dispositions in the
ordinary course of business not in excess of $20,000,000 in the aggregate for
such Guarantor, any other Guarantor and the Issuer in any fiscal year; (iii) any
sales or dispositions of surplus, obsolete or worn-out equipment; (iv) any sales
or dispositions required for compliance with applicable Law or necessary
Governmental Approvals; (v) any sales or dispositions of assets permitted under
Section 6.14 or 7.6; or (vi) any other sale or other disposition so long as
after giving effect to such events, the Rating Agencies shall have confirmed
their respective ratings of the Bonds in effect immediately prior to such sale
or other disposition.

       SECTION 7.12 Modification of Certain Documents. Without the prior consent
of the Majority Holders of all Outstanding Bonds, no Guarantor will agree or
consent to any termination, modification, supplement, replacement or waiver of
any Transaction Document, unless such termination, modification, supplement,
replacement or waiver could not, individually or collectively with all other
such terminations, modifications, supplements, replacements and waivers,
reasonably be expected to have a Material Adverse Effect.

                                    ARTICLE 8

                               REDEMPTION OF BONDS

       SECTION 8.1 Optional Redemption; Redemption Price. The Issuer at its
option, may, at any time, redeem the Bonds of any series, in whole or in part at
the Redemption Price plus any premium set forth in the related Series
Supplemental Indenture. Redemption of Bonds of any series shall be made in
accordance with the terms of such Bonds and, to the extent that this Article
does not conflict with such terms, the succeeding sections of this Article.

       SECTION 8.2 Election or Requirement to Redeem; Notice to Trustee. The
requirement or election of the Issuer to redeem any Bonds shall be evidenced by
an Issuer Order. If the Issuer has elected or is required to redeem any Bonds,
the Issuer shall, at least 30 days but not more than 60 days prior to the date
upon which notice of redemption is required to be given to the Holders pursuant
to Section 8.4 hereof (unless a shorter period shall be satisfactory to the
Trustee), deliver to the Trustee an Issuer Order specifying the date on which
such redemption shall occur (the "Redemption Date") as determined in accordance
with this Article 8, the series

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and principal amount of Bonds to be redeemed and evidence that the moneys
necessary for such redemption will be delivered to the Trustee not later than
the Business Day prior to the Redemption Date. Upon receipt of any such Issuer
Order with respect to a mandatory redemption, the Trustee shall establish a
non-interest bearing special purpose trust account (the "Mandatory Redemption
Account") into which shall be deposited by the Issuer not later than one
Business Day prior to the Redemption Date, immediately available amounts to be
held by the Trustee and applied to the redemption of such Bonds. As collateral
security for the prompt and complete payment and performance when due of all its
obligations with respect to the Bonds and under this Indenture, the Issuer has
pledged, assigned, hypothecated and transferred to the Trustee for the benefit
of the Holders a Lien on and security interest in and to the Mandatory
Redemption Account. The Mandatory Redemption Account shall at all times be in
the exclusive possession of, and under the exclusive dominion and control of,
the Trustee. In the case of any redemption of Bonds prior to the expiration of
any restriction on such redemption provided in the terms of such Bonds, the
Series Supplemental Indenture relating thereto or elsewhere in this Indenture,
the Issuer shall furnish the Trustee with an Officer's Certificate and Opinion
of Counsel evidencing compliance with such restriction or condition.

       SECTION 8.3 Mandatory Redemption; Selection of Bonds to Be Redeemed;
Redemption Price.

       (a) Unless otherwise provided in a Series Supplemental Indenture and in
accordance with Section 7 of the Collateral Agency and Intercreditor Agreement,
Outstanding Bonds shall be redeemed in whole or in part on a pro rata basis,
prior to maturity, at the Redemption Price if (x) an Event of Loss shall occur
and the Issuer has either (i) determined that the Affected Property cannot be
rebuilt, repaired or restored or (ii) decided not to rebuild, repair or restore
the Affected Property and (y) Loss Proceeds exceed $10,000,000. All Loss
Proceeds in excess of $10,000,000 to be distributed for the benefit of the
Holders after giving effect to the distribution of Loss Proceeds to the other
Secured Parties under Section 7(d) of the Collateral Agency and Intercreditor
Agreement, shall be applied to the pro rata redemption of the Bonds pursuant to
this Section 8.3. The Redemption Date shall be any date during the 90-day period
following the date of the Issuer's determination (x) that the Affected Property
cannot be rebuilt, repaired or restored or (y) not to rebuild, repair or restore
the Affected Property, as the case may be (taking into account the notice
requirements set forth in Section 8.4).

       (b) Unless otherwise provided in a Series Supplemental Indenture and in
accordance with Section 7 of the Collateral Agency and Intercreditor Agreement,
the Outstanding Bonds shall be redeemed in whole or in part prior to maturity at
the Redemption Price if an Event of Loss shall occur and it has been determined
that the Affected Property be rebuilt, repaired or restored and the amount of
the Loss Proceeds, as the case may be, remaining after the payment of the actual
total cost of such rebuilding, repair or restoration exceeds $5,000,000. The
amount by which all of the Loss Proceeds exceeds the actual total cost of
rebuilding, repairing or restoring the Affected Property which is in excess of
$5,000,000 to be distributed for the benefit of the Holders after giving effect
to the distribution of Loss Proceeds to the other Secured Parties under Section
7(d) of the Collateral Agency and Intercreditor Agreement shall be applied by
the Trustee to the pro rata redemption of the Bonds pursuant to this Article 8.
The Redemption Date shall be any date during the 90-day period following the
date of the delivery of an Officer's Certificate of the Issuer to the Trustee
certifying completion

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of the rebuilding, repair or restoration of the Affected Property (taking into
account the notice requirements set forth in Section 8.4).

       (c) Upon any redemption of the Bonds in accordance with this Section 8.3,
the scheduled principal amortization of the Bonds of a series shall be reduced
by an amount equal to the product of (x) the scheduled principal amortization of
the Bonds of such series then in effect multiplied by (y) a fraction, the
numerator of which is equal to the principal amount of the Outstanding Bonds of
such series to be redeemed and the denominator of which is the principal amount
of the Outstanding Bonds of such series immediately prior to such redemption.

       (d) Except as otherwise specified in the Series Supplemental Indenture
relating to the Bonds of a series, if less than all the Bonds of such series are
to be redeemed pursuant to Section 8.3(a) or (b), the Bonds of such series shall
be redeemed ratably by the Trustee from the Outstanding Bonds of such series not
previously called for redemption in whole.

       (e) For all purposes of this Indenture, unless the context otherwise
requires, all provisions relating to the redemption of Bonds shall relate, in
the case of any Bonds redeemed or to be redeemed only in part, to the portion of
the principal amount of such Bonds that has been or is to be redeemed.

       For the purpose of redemptions of any Bonds pursuant to clause (a) or (b)
above, the Redemption Price shall equal the principal amount of such Bond
Outstanding on the Redemption Date, plus interest accrued and unpaid to but
excluding the Redemption Date.

       SECTION 8.4 Notice of Redemption. Except as otherwise specified in the
Series Supplemental Indenture relating to the Bonds of a series to be redeemed,
notice of redemption shall be given to the Holders of Bonds of such series to be
redeemed at least 30 days (unless a shorter period shall be satisfactory to the
Trustee) but not more than 60 days prior to the Redemption Date. All notices of
redemption shall state:

       (a) the Redemption Price;

       (b) the Redemption Date;

       (c) if less than all of the Outstanding Bonds of any series are to be
   redeemed, the portion of the principal amount of each Bond of such series to
   be redeemed in part, and a statement that, on and after the Redemption Date,
   upon surrender of such Bond, a new Bond or Bonds of such series in principal
   amount equal to the remaining unpaid principal amount thereof will be issued;

       (d) that on the Redemption Date, interest thereon will cease to accrue on
   and after said date;

       (e) the Place or Places of Payment where such Bonds are to be surrendered
   for payment of the Redemption Price; and

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       (f) that the deposit by the Issuer with the Trustee of an amount of
   immediately available funds to pay the Bonds to be redeemed in full is a
   condition precedent to the Redemption.

       Notice of redemption of Bonds to be redeemed shall be given by the Issuer
or, at the Issuer's request, by the Trustee in the name and at the expense of
the Issuer.

       SECTION 8.5 Bonds Payable on Redemption Date. Notice of redemption having
been given as aforesaid, and the conditions, if any, set forth in such notice
having been satisfied, the Bonds or portions thereof so to be redeemed shall, on
the Redemption Date become due and payable, and from and after such date such
Bonds or portions thereof shall cease to bear interest. Upon surrender of any
such Bond for redemption in accordance with such notice, an amount in respect of
such Bond or portion thereof shall be paid as provided therein; provided,
however, that any payment of interest on any Bond the Scheduled Payment Date of
which is on or prior to the Redemption Date shall be payable to the Holder of
such Bond or one or more Predecessor Bonds, registered as such at the close of
business on the related Regular Record Date according to the terms of such Bond
and subject to the provisions of Section 2.10.

       SECTION 8.6 Bonds Redeemed in Part. Any Bond that is to be redeemed only
in part shall be surrendered at a Place of Payment therefor (with, if the Issuer
or the Trustee so requires, due endorsement by, or a written instrument of
transfer in form satisfactory to the Issuer and the Trustee duly executed by,
the Holder thereof or its attorney duly authorized in writing), and the Issuer
shall execute, and the Trustee shall authenticate and make available for
delivery to the Holder of such Bond without service charge, a new Bond or Bonds
of the same series, of any authorized denomination requested by such Holder and
of like tenor and in aggregate principal amount equal to and in exchange for the
remaining unpaid principal amount of the Bond so surrendered.

                                    ARTICLE 9

                        REPURCHASE UPON CHANGE OF CONTROL

       SECTION 9.1. Change of Control.

       (a) Upon the occurrence of a Change of Control, each Holder shall have
the right to require the Issuer to repurchase all or any part of such Holder's
Bonds at a purchase price in cash equal to 101% of the then Outstanding
principal amount of a Bond, plus accrued and unpaid interest to but excluding
the date of purchase (subject to the right of Holders of record on the relevant
record date to receive interest due on the relevant interest payment date in
accordance with the terms of this Indenture); provided, however, that
notwithstanding the occurrence of a Change of Control, the Issuer shall not be
obligated to purchase any Bond pursuant to this Section 9.1 to the extent that
the Issuer has exercised its rights to redeem such Bond as described in Section
8.2.

       (b) Within 30 days following any Change of Control, the Issuer shall mail
a notice to each Holder with a copy thereof to the Trustee stating, among other
things: (1) that a

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Change of Control has occurred and that such Holder has the right to require the
Issuer to purchase all or any portion of such Holder's Bonds at a purchase price
in cash equal to 101% of the principal amount of such Bond, plus accrued and
unpaid interest to but excluding the date of purchase (subject to the right of
Holders of record on a Regular Record Date to receive interest due on the
relevant Scheduled Payment Date in accordance with the terms of this Indenture);
(2) the circumstances and relevant facts regarding such Change of Control
(including information with respect to pro forma historical income, cash flow
and capitalization, each after giving effect to such Change of Control); (3) the
repurchase date (which shall be no earlier than 30 days nor later than 60 days
from the date such notice is mailed); and (4) the instructions determined by the
Issuer, consistent with this Section 9.1, that a Holder must follow in order to
have its Bonds or any portion thereof purchased.

       (c) The Issuer shall comply, to the extent applicable, with the
requirements of Section 14(e) of the Exchange Act and any other securities laws
or regulations in connection with the repurchase of Bonds pursuant to this
Section 9.1. To the extent that the provisions of any securities laws or
regulations conflict with provisions of this Section 9.1, the Issuer shall
comply with the applicable securities laws and regulations and shall not be
deemed to have breached their obligations described above by virtue thereof.

                                   ARTICLE 10

                         EVENTS OF DEFAULT AND REMEDIES

       SECTION 10.1 Events of Default. The term "Event of Default", whenever
used herein, shall mean any of the following events (whatever the reason for
such event and whether it shall be voluntary or involuntary or come about or be
affected by operation of law, or be pursuant to or in compliance with any
applicable Law), and any such event shall continue to be an Event of Default if
and for so long as it shall not have been remedied:

       (a) the Issuer defaults in the payment of any principal or interest on
   any Bond when the same becomes due and payable, whether by scheduled maturity
   or required redemption or by acceleration or otherwise, for 15 days or more;

       (b) default in the performance or observance in any material respect of
   any other term, covenant, or obligation of the Issuer under this Indenture,
   not otherwise expressly defined as an Event of Default, and the continuance
   of such default for more than 60 days after the earliest to occur of (i)
   actual knowledge of an executive officer of the Issuer of such default, (ii)
   the time at which an executive officer of the Issuer should reasonably have
   had knowledge of such default or (iii) notice from the Trustee or the Holders
   of such default;

       (c) default or defaults under one or more agreements, instruments,
   mortgages, bonds, debentures or other evidences of Indebtedness under which
   the Issuer or any Guarantor then has outstanding Indebtedness in excess of
   $15,000,000, individually or in the aggregate, and such default or defaults
   have resulted in the acceleration of the maturity of such Indebtedness and
   such acceleration has not been annulled or rescinded;

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       (d) an involuntary proceeding shall be commenced or an involuntary
   petition shall be filed seeking (i) liquidation, reorganization or other
   relief in respect of the Issuer or any Guarantor or its debts, or of a
   substantial part of its assets, under any Federal, state or foreign
   bankruptcy, insolvency, receivership or similar law now or hereafter in
   effect or (ii) the appointment of a receiver, trustee, custodian,
   sequestrator, conservator or similar official for the Issuer or any Guarantor
   or for a substantial part of its assets, and, in any such case, such
   proceeding or petition shall continue undismissed for a period of 60 or more
   days or an order or decree approving or ordering any of the foregoing shall
   be entered;

       (e) the Issuer or any Guarantor shall (i) voluntarily commence any
   proceeding or file any petition seeking liquidation, reorganization or other
   relief under any Federal, state or foreign bankruptcy, insolvency,
   receivership or similar law now or hereafter in effect, (ii) consent to the
   institution of, or fail to contest in a timely and appropriate manner, any
   proceeding or petition described in clause (h) of this Article, (iii) apply
   for or consent to the appointment of a receiver, trustee, custodian,
   sequestrator, conservator or similar official for itself or for a substantial
   part of its assets, (iv) file an answer admitting the material allegations of
   a petition filed against it in any such proceeding, (v) make a general
   assignment for the benefit of creditors or (vi) take any action for the
   purpose of effecting any of the foregoing;

       (f) any event described in clauses (d) or (e) above occurs with respect
   to NRG Energy, NRG Power Marketing, NRG Operations or any Operator (so long
   as such Operator continues to be Subsidiary of NRG Energy), in each case to
   the extent a party to any Transaction Document, and remains uncured for the
   grace periods provided in such clauses, provided, however, that in respect of
   such an event relating to any Operator, the Issuer shall have an additional
   60-day period within which to enter into a replacement operating arrangement,
   and provided further, that in no case shall such an event in respect of an
   Operator constitute an Event of Default unless it has a Material Adverse
   Effect on the Issuer and the Guarantors taken as a whole;

       (g) the Issuer or any Guarantor shall become unable, admit in writing its
   inability or fail generally to pay its debts as they become due;

       (h) one or more judgments for the payment of money in an aggregate amount
   in excess of $25,000,000 shall be rendered against the Issuer or any of the
   Guarantors or any combination thereof and the same shall remain undischarged
   or unpaid for a period of 60 consecutive days during which execution shall
   not be effectively stayed;

       (i) the Issuer shall be terminated, dissolved or liquidated (as a matter
   of law or otherwise);

       (j) the Liens created by the Collateral Documents shall at any time not
   constitute a valid and perfected Lien on the collateral intended to be
   covered thereby (to the extent perfection by filing, registration,
   recordation or possession is required herein or therein) in favor of the
   Trustee, free and clear of all other Liens (other than Liens permitted under
   this Indenture or under the respective Collateral Documents), or, except for
   expiration in

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   accordance with its terms, any of the Collateral Documents shall for
   whatever reason be terminated or cease to be in full force and effect, or the
   enforceability thereof shall be contested by any Obligor or Member;

       (k) either (i) this Indenture or any other Financing Document is declared
   in a final non-appealable judgment to be unenforceable against the Issuer or
   any Guarantor or the Issuer or any Guarantor shall have expressly repudiated
   its obligations thereunder; or (ii) any other Transaction Document is
   declared in a final non-applicable judgment to be unenforceable against any
   party thereto, or any such party shall have expressly repudiated its
   obligations thereunder and ceased to perform such obligations, or defaulted
   in the performance or observance of any of its material obligations
   thereunder and such default has continued unremedied for a period of five
   days or more or any such party is the subject of any proceeding under the
   Federal Bankruptcy Code;

       (l) default by the Issuer, any Guarantor or any counterparty under or
   invalidity of any Power Sales Agreement, Operation and Maintenance Agreement
   or Corporate Services Agreement, to the extent such default under or
   invalidity of any such agreement (x) continues for 30 consecutive days and
   (y) could reasonably be expected to have a Material Adverse Effect on the
   Issuer and the Guarantors taken as a whole; or

       (m) failure to renew or replace any Operation and Maintenance Agreement
   (or to make a substantially similar arrangement with respect to the operation
   and maintenance of a Facility) upon (i) termination by a Guarantor or an
   Operator, after having given 180 days' notice of its intent to terminate,
   within 5 days of such termination, (ii) termination by any Guarantor, within
   5 days of such termination, or (iii) termination by any Operator, within 30
   days of such termination.

       SECTION 10.2 Acceleration of Maturity; Rescission and Annulment. If an
Event of Default described in paragraph (a) of Section 10.1 occurs and is
continuing with respect to Bonds of any series, then and in each and every such
case, unless the principal of all the Bonds of such series shall have already
become due and payable, either the Trustee or the Holders of not less than
331/3% in aggregate principal amount of the Bonds of such series then
Outstanding hereunder, or, in the event of any Event of Default described in
paragraph (b), (c), (f), (h), (i), (j), (k), (l) or (m) of Section 10.1, the
Majority Holders of Bonds of such series then outstanding hereunder, by notice
in a writing to the Issuer (and to the Trustee if given by Holders), may
declare the principal amount of all the Bonds of such series then Outstanding
and all accrued interest thereon to be due and payable immediately, and upon
any such declaration the same shall become and shall be immediately due and
payable, anything in this Indenture or in the Bonds of such series contained to
the contrary notwithstanding. If an Event of Default described in paragraph
(d), (e) or (g) of Section 10.1 occurs and is continuing, then and in each and
every such case, the principal amount of the Bonds then Outstanding and all
accrued interest thereon shall, without any notice to the Issuer or any other
act on the part of the Trustee or any Holder of the Bonds, become and be
immediately due and payable, anything in this Indenture or in the Bonds
contained to the contrary notwithstanding.

       At any time after such declaration of acceleration has been made with
respect to the Bonds of any series and before a judgment or decree for payment
of the money due has been

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obtained by the Trustee as hereinafter in this Article provided, the Majority
Holders of the Bonds of such series, by written notice to the Issuer and the
Trustee, may receive and annul such declaration and its consequences if:

       (i) there shall have been paid to or deposited with the Trustee a sum
   sufficient to pay

          (A) all overdue installments of interest on the Bonds of such series,

          (B) the principal of and premium, if any, on any Bonds of such series
       that have become due other than by such declaration of acceleration and
       interest thereon at the respective rates provided in the Bonds of such
       series for late payments of principal or premium,

          (C) to the extent that payment of such interest is lawful, interest
       upon overdue installments of interest at the respective rates provided in
       the Bonds for late payments of interest, and

          (D) all sums paid or advanced by the Trustee hereunder and the
       reasonable compensation, expenses, disbursements, and advances of the
       Trustee, its agents and counsel, and

       (ii) all Events of Default, other than the nonpayment of the principal of
   the Bonds that has become due solely by such acceleration, have been cured or
   waived as provided in Section 10.12.

       No such rescission shall affect any subsequent default or impair any
right consequent thereon.

       SECTION 10.3 Trustee May File Proofs of Claim; Appointment of Trustee as
Attorney-in-Fact in Judicial Proceedings. In case of pendency in any
receivership, insolvency, bankruptcy, liquidation, readjustment, reorganization
or any other judicial proceedings relating to the Issuer or any obligor on the
Bonds or the property of the Issuer or of such other obligor or their creditors,
the Trustee (irrespective of whether the principal of the Bonds shall then be
due and payable as therein expressed or by declaration or otherwise and
irrespective of whether the Trustee shall have made any demand on the Issuer for
payment of overdue principal or interest) shall be entitled and empowered by
intervention in such proceedings or otherwise

       (i) to file and prove a claim for the whole amount of principal (and
   premium, if any) and interest owed and unpaid in respect of the Bonds and to
   file such other papers or documents as may be necessary and advisable in
   order to have the claims of the Trustee (including any claim for the
   reasonable compensation expenses, disbursements and advances of the Trustee,
   its agents and counsel and all other amounts due the Trustee under Section
   10.4) and of the Holders allowed in such judicial proceeding, and

       (ii) to collect and receive any moneys or other property payable or
   deliverable on any such claims and to distribute same;

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and any receiver, assignee, trustee, liquidator or sequestrator in any such
judicial proceeding is hereby authorized by each Holder to make such payment to
the Trustee and in the event that the Trustee shall consent to the making of
such payments directly to the Holders, to pay to the Trustee any amount due to
it for the reasonable compensation, expenses, disbursements and advances of the
Trustee, its agents and counsel, and any other amounts due the Trustee under
Section 10.5.

       Nothing herein contained shall be deemed to authorize the Trustee to
authorize or consent to or accept or adopt on behalf of any Holder any plan of
reorganization, arrangement, adjustment or composition affecting the Bonds or
the rights of any Holder thereof, or to authorize the Trustee to vote in respect
of the claim of any Holder in any such proceeding.

       SECTION 10.4 Trustee May Enforce Claims Without Possession of Bonds. All
rights of action and claims under this Indenture or the Bonds of any series may
be prosecuted and enforced by the Trustee without the possession of any of the
Bonds of such series or the production thereof in any proceeding relating
thereto, and any such proceeding instituted by the Trustee shall be brought in
its own name as trustee of an express trust, and any recovery of judgment shall,
after provision for the payment of the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agent and counsel, be for the
ratable benefit of the Holders of the Bonds of the series in respect of which
such judgment has been recovered.

       SECTION 10.5 Application of Money Collected. Any money collected by the
Trustee with respect to a series of Bonds pursuant to this Article shall be
applied in the following order, at the date or dates fixed by the Trustee and,
in case of the distribution of such money on account of principal (or premium,
if any) or interest, upon presentation of the Bonds of such series and the
notation thereon of the payment if only partially paid and upon surrender
thereof if fully paid:

       FIRST: To the payment of all amounts due the Trustee under Section 11.5.

       SECOND: To the payment of the amounts then due and unpaid upon the Bonds
of that series for principal (and premium, if any) and interest, in respect of
which or for the benefit of which such money has been collected, ratably among
Bonds within each series and among the series, without preference or priority of
any kind, according to the amounts due and payable on such Bonds for principal
(and premium, if any) and interest, respectively.

       SECTION 10.6 Limitation on Suits. No Holder of any Bond of any series
shall have any right to institute any proceeding, judicial or otherwise, with
respect to this Indenture or the Bonds or for the appointment of a receiver or
trustee, or for any other remedy hereunder, unless

       (a) such Holder has previously given written notice to the Trustee of a
   continuing Event of Default with respect to Bonds of such series;

       (b) the Holders of not less than 25% in aggregate principal amount of
   then Outstanding Bonds of such series shall have made written request to the
   Trustee to institute proceedings in respect of such Event of Default in its
   own name as Trustee hereunder;

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       (c) such Holder or Holders have offered to the Trustee reasonable
   indemnity against the costs, expenses and liabilities to be incurred in
   compliance with such request;

       (d) the Trustee for 60 days after its receipt of such notice, request and
   offer of indemnity has failed to institute any such proceeding; and

       (e) no direction inconsistent with such written request has been given to
   the Trustee during such 60-day period by the Majority Holders of such series;

it being understood and intended that no one or more Holders of Bonds of such
series shall have any right in any manner whatever by virtue of, or by availing
of, any provision of this Indenture to affect, disturb or prejudice the rights
of any other Holders of Bonds of such series, or to obtain or to seek to obtain
priority or preference over any other such Holders or to enforce any right under
this Indenture, except in the manner herein provided and for the equal and
proportionate benefit of all the Holders of all Bonds of such series.

       SECTION 10.7 Unconditional Right of Holders to Receive Principal, Premium
and Interest. Notwithstanding any other provisions in this Indenture, the Holder
of any Bond shall have the right, which is absolute and unconditional, to
receive payment of the principal of (and premium, if any) and interest on such
Bond on the respective maturities expressed in such Bond (or, in the case of
redemption or repayment, on the Redemption Date or Repayment Date, as the case
may be) and to institute suit for the enforcement of any such payment, and such
right shall not be impaired without the consent of such Holder.

       SECTION 10.8 Restoration of Rights and Remedies. If the Trustee or any
Holder has instituted any proceeding to enforce any right or remedy under this
Indenture and such proceeding has been discontinued or abandoned for any reason,
then and in every such case the Issuer, the Trustee and the Holders shall,
subject to any determination in such proceeding, be restored severally and
respectively to their former positions hereunder, and thereafter all rights and
remedies of the Trustee and the Holders shall continue as though no such
proceeding had been instituted.

       SECTION 10.9 Rights and Remedies Cumulative. Except as otherwise provided
in the last paragraph of Section 2.9, no right or remedy herein conferred upon
or reserved to the Trustee or to the Holders is intended to be exclusive of any
other right or remedy, and every right and remedy shall, to the extent permitted
by law, be cumulative and in addition to every other right and remedy given
hereunder or now or hereafter existing at law or in equity or otherwise. The
assertion or employment of any right or remedy hereunder, or otherwise, shall
not prevent the concurrent assertion or employment of any other appropriate
right or remedy.

       SECTION 10.10 Delay or Omission Not Waiver. No delay or omission of the
Trustee or of any Holder of any Bond to exercise any right or remedy accruing
upon any Event of Default shall impair any such right or remedy or constitute a
waiver of any such Event of Default or an acquiescence therein. Every right and
remedy given by this Article or by law to the Trustee or to the Holders may be
exercised from time to time, and as often as may be deemed expedient, by the
Trustee or by the Holders, as the case may be. No waiver of any Event of

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Default, whether by the Trustee or by the Holders, shall extend to or shall
affect any subsequent Event of Default or shall impair any remedy or right
consequent thereon.

       SECTION 10.11 Control by Holders. The Holders of a majority in principal
amount of then Outstanding Bonds of any series shall have the right to direct
the time, method and place of conducting any proceeding for any remedy available
to the Trustee or exercising any trust or power conferred on the Trustee with
respect to the Bonds of such series; provided that

       (a) the Trustee shall have the right to decline to follow any such
   direction if the Trustee, being advised by counsel, determines that the
   action so directed may not lawfully be taken or would conflict with this
   Indenture or if the Trustee in good faith shall, by a Responsible Officer,
   determine that the proceedings so directed would involve it in personal
   liability or it reasonably believes it will not adequately be indemnified
   against the costs, expenses and liabilities which might be incurred by it in
   complying with its request or be unjustly prejudicial to the Holders not
   taking part in such direction, and

       (b) the Trustee may take any other action deemed proper by the Trustee
   which is not inconsistent with such direction.

       SECTION 10.12 Waiver of Past Defaults. The Majority Holders of any series
may on behalf of the Holders of all the Bonds of such series waive any past
default hereunder with respect to such series and its consequences, except a
default not theretofore cured

       (a) in the payment of the principal of (or premium, if any) or interest
   on any Bond of such series, or in the payment of any sinking or purchase fund
   or analogous obligation with respect to the Bonds of such series, or

       (b) in respect of a covenant or provision hereof which under Article 14
   cannot be modified or amended without the consent of the Holder of each
   Outstanding Bond of such series.

       Upon any such waiver, such default shall cease to exist, and any Event of
Default arising therefrom shall be deemed to have been cured, for every purpose
of this Indenture; but no such waiver shall extend to any subsequent or other
default or impair any right consequent thereon.

       SECTION 10.13 Undertaking for Costs. All parties to this Indenture agree,
and each Holder of any Bond by its acceptance thereof shall be deemed to have
agreed, that any court may in its discretion require, in any suit for the
enforcement of any right or remedy under this Indenture, or in any suit against
the Trustee for any action taken or omitted by it as Trustee, the filing by any
part litigant in such suit of an undertaking to pay the costs of such suit, and
that such court may in its discretion assess reasonable costs, including
reasonable attorneys' fees, against any party litigant in such suit, having due
regard to the merits and good faith of the claims or defenses made by such party
litigant; but the provisions of this Section shall not apply to any suit
instituted by the Trustee, to any suit instituted by any Holder, or group of
Holders, holding in the aggregate more than 10% in principal amount of then
Outstanding Bonds of any

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series to which the suit relates, or to any suit instituted by any Holder for
the enforcement of the payment of the principal of (or premium, if any) or
interest on any Bond on or after the respective maturities expressed in such
Bond (or, in the case of redemption or repayment, on or after the Redemption
Date or Repayment Date).

       SECTION 10.14 Waiver of Stay or Extension Laws. The Issuer covenants (to
the extent that it may lawfully do so) that it will not at any time insist upon,
or plead, or in any manner whatsoever claim or take the benefit or advantage of,
any stay or extension law wherever enacted, now or at any time hereafter in
force, which may affect the covenants or the performance of this Indenture; and
the Issuer (to the extent that it may lawfully do so) hereby expressly waives
all benefit or advantage of any such law, and covenants that it will not hinder,
delay or impede the execution of any power herein granted to the Trustee, but
will suffer and permit the execution of every such power as though no such law
had been enacted.

                                   ARTICLE 11

                             CONCERNING THE TRUSTEE

       SECTION 11.1 Certain Rights and Duties of Trustee. The Trustee, prior to
the occurrence of an Event of Default and after curing or waiving all Events of
Default that may have occurred, undertakes to perform only such duties as are
specifically set forth in this Indenture and no implied covenants or obligations
shall be read into this Indenture against the Trustee. In case an Event of
Default has occurred (which has not been cured or waived) the Trustee shall
exercise such of the rights and powers vested in it by this Indenture, and use
the same degree of care and skill in their exercise, as a prudent man would
exercise or use under the circumstances in the conduct of his own affairs.

       Except as otherwise provided in Section 315 of the Trust Indenture Act:

       (a) The Trustee may conclusively rely and shall be fully protected in
   acting, or refraining from acting, upon any resolution, certificate,
   statement, instrument, opinion, report, notice, request, consent, order,
   bond, debenture or other paper or document reasonably believed by it to be
   genuine and to have been signed or presented by the proper party or parties;
   but in the case of any such certificates or opinions which by the provisions
   hereof are specifically required to be furnished to the Trustee, the Trustee
   shall be under a duty to examine the same to determine whether or not they
   conform to the requirements of this Indenture but need not verify the
   contents thereof.

       (b) Any request, direction, order or demand of the Issuer mentioned
   herein shall be sufficiently evidenced by an Officer's Certificate (unless
   other evidence in respect thereof be herein specifically prescribed); and any
   resolution of the Board of Directors shall be evidenced to the Trustee by a
   copy thereof certified by the secretary or an assistant secretary of the
   Issuer.

       (c) The Trustee shall be under no obligation to exercise any of the
   trusts or powers vested in it by this Indenture, and may refuse to perform
   any duty or exercise any

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   such rights or powers unless it shall have been offered reasonable
   security or indemnity to its satisfaction against the costs, expenses and
   liabilities which may reasonably be incurred therein or thereby.

       (d) The Trustee shall not be liable for any action taken, suffered or
   omitted by it in good faith and reasonably believed by it to be authorized or
   within the discretion or rights or powers conferred upon it by this Indenture
   or with respect to any action it takes or omits to take in good faith in
   accordance with a direction received by it from Holders holding a sufficient
   percentage of Bonds to give such direction as permitted by this Indenture.

       (e) Prior to the occurrence of an Event of Default with respect to any
   series of Bonds hereunder and after the curing or waiving of all Events of
   Default with respect to such series of Bonds the Trustee shall not be bound
   to make any investigation into the facts or matters stated in any resolution,
   certificate, statement, instrument, opinion, report, notice, request,
   consent, order, approval, appraisal, bond, debenture or other paper or
   document with respect to such series of Bonds unless requested in writing so
   to do by the Holders of not less than a majority in aggregate principal
   amount of the Bonds of such series then Outstanding; provided that, if the
   payment within a reasonable time to the Trustee of the reasonable costs,
   expenses or liabilities likely to be incurred by it in the making of such
   investigation is, in the opinion of the Trustee, not reasonably assured to
   the Trustee by the security afforded to it by the terms of this Indenture,
   the Trustee may require reasonable indemnity against such expenses or
   liabilities as a condition to so proceeding. The reasonable expense of every
   such investigation shall be paid by the Issuer or, if paid by the Trustee,
   shall be repaid by the Issuer upon demand.

       (f) The Trustee may execute any of the trusts or powers hereunder or
   perform any duties hereunder either directly or by or through agents,
   attorneys, custodians or nominees and the Trustee shall not be responsible
   for any misconduct or negligence on the part of any agent, attorney custodian
   or nominee appointed with due care by it hereunder or under any Collateral
   Document.

       (g) The Trustee shall not be liable for any error of judgment made in
   good faith by a Responsible Officer or Responsible Officers of the Trustee
   unless it shall be proved that the Trustee was negligent in ascertaining the
   pertinent facts or the action or failure to act by such Responsible Officers
   was unreasonable.

       (h) The Trustee shall not be liable with respect to any action taken or
   omitted to be taken by it in good faith in accordance with any direction of
   the Issuer given under this Agreement.

       (i) The Trustee shall not be bound to make any investigation into the
   facts or matters stated in any resolution, certificate, statement,
   instrument, opinion, report, notice, request, consent, entitlement order,
   approval or other paper or document.

       (j) The Trustee shall have no obligation to invest and reinvest any cash
   held pursuant to this Agreement in the absence of timely and specific written
   investment

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   direction from the Issuer. In no event shall the Trustee be liable for
   the selection of investments or for investment losses incurred thereon. The
   Trustee shall have no liability in respect of losses incurred as a result of
   the liquidation of any investment prior to its stated maturity or the failure
   of the Issuer to provide timely written investment direction.

       None of the provisions contained in this Indenture shall require the
Trustee to expend or risk its own funds or otherwise incur personal financial
liability in the performance of any of its duties or in the exercise of any of
its rights or powers, if there shall be a reasonable ground for believing that
the repayment of such funds or indemnity satisfactory to it against such
liability is not reasonably assured to it.

       The Trustee may consult with counsel and the written advice or opinion of
counsel shall be full and complete authorization and protection in respect of
any action taken or omitted by it hereunder in good faith and in accordance with
such written advice or opinion of counsel.

       SECTION 11.2 Trustee Not Responsible for Recitals, Etc. The recitals
contained herein and in the Bonds, except the Trustee's certificate of
authentication, shall be taken as the statements of the Issuer and the Trustee
assumes no responsibility for the correctness of the same. The Trustee makes no
representations as to the validity or sufficiency of this Indenture, the
Collateral or of the Bonds. The Trustee shall not be accountable for the use or
application by the Issuer of any of the Bonds or of the proceeds of such Bonds.

       SECTION 11.3 Trustee and Others May Hold Bonds. The Trustee or any Paying
Agent or Security Registrar or any other Authorized Agent of the Trustee, or any
Affiliate thereof, in its individual or any other capacity, may become the owner
or pledgee of Bonds and may otherwise deal with the Issuer, or any other obligor
on the Bonds with the same rights it would have if it were not Trustee, Paying
Agent, Security Registrar or such other Authorized Agent.

       SECTION 11.4 Moneys Held by Trustee or Paying Agent. All moneys received
by the Trustee or any Paying Agent shall, until used or applied as herein
provided, be held in trust for the purposes for which they were received, but,
other than the Mandatory Redemption Account, need not be segregated from other
funds except to the extent required by law. Neither the Trustee nor any Paying
Agent shall be under any liability for interest on any moneys received by it
hereunder except such as it may agree in writing with the Issuer to pay thereon.

       SECTION 11.5 Compensation of Trustee and Its Lien. For so long as any of
the Bonds shall remain outstanding, the Issuer covenants and agrees to pay to
the Trustee (all references in this Section 11.5 to the Trustee shall be deemed
to apply to the Trustee in its capacities as Trustee, Paying Agent and Security
Registrar) from time to time, and the Trustee shall be entitled to, reasonable
compensation for all services rendered by it hereunder (which shall be agreed to
from time to time by the Issuer and the Trustee and which shall not be limited
by any provision of law in regard to the compensation of a trustee of an express
trust), and, except as herein otherwise expressly provided, the Issuer will pay
or reimburse the Trustee upon its request for all reasonable expenses and
disbursements incurred or made by the Trustee in accordance with any of the
provisions of this Indenture (including the reasonable compensation

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and the reasonable expenses, advances and disbursements of its counsel and of
all persons not regularly in its employ) except any such expense or disbursement
as may arise from its gross negligence or bad faith. The Issuer also covenants
and agrees to indemnify the Trustee for, defend, and hold harmless the Trustee
and its officers, directors, employees, representatives and agents from and
against, any loss, liability, claim, damage or expense incurred without gross
negligence or bad faith on the part of the Trustee or any of its employees,
officers or agents, arising out of or in connection with the acceptance or
administration of the trust or trusts hereunder and this Indenture, including
liability which the Trustee may incur as a result of failure to withhold, pay or
report Taxes and including the costs and expenses of defending itself against
any claim or liability in the premises and including, without limitation, any
loss, liability, claim, damage or expense relating to or arising out of any
Environmental Law. The obligations of the Issuer under this Section shall
constitute additional Indebtedness hereunder. In no event shall the Trustee be
liable for special, indirect or consequential loss or damages whatsoever
(including, but not limited to lost profits), even if the Trustee has been
advised of the likelihood of such damage and regardless of the form of action
taken.

       The obligations of the Issuer under this Section 11.5 shall survive
payment in full of the Bonds, the resignation or removal of the Trustee and the
termination of this Indenture.

       When the Trustee or any predecessor Trustee incurs expenses or renders
services in connection with the performance of its obligations hereunder
(including its services as paying agent, if so appointed by the Issuer) after an
Event of Default specified in Section 10.1(f) or (a) occurs, the expenses and
compensation for such services are intended to constitute expenses of
administration under applicable bankruptcy, insolvency or other similar United
States Federal or state law to the extent provided in Section 503(b)(5) of the
Federal Bankruptcy Code.

       SECTION 11.6 Right of Trustee to Rely on Officer's Certificates and
Opinions of Counsel. Before the Trustee acts or refrains from acting with
respect to any matter contemplated by this Indenture, it may require an
Officer's Certificate of the Issuer or an Opinion of Counsel, which shall
conform to the provisions of Section 1.3. The Trustee shall not be liable for
any action it takes or omits to take in good faith in reliance on such
certificate or opinion as set forth in Section 11.1(g).

       SECTION 11.7 Persons Eligible for Appointment As Trustee. There shall at
all times be a Trustee hereunder which shall at all times be a corporation which
complies with the eligibility requirements of the Trust Indenture Act, having a
combined capital and surplus of at least $100,000,000. If such corporation
publishes reports of condition at least annually, pursuant to law or to the
requirements of a supervising or examining authority referred to in Section
310(a) of the Trust Indenture Act, then for the purposes of this Section 11.7,
the combined capital and surplus of such corporation shall be deemed to be its
combined capital and surplus as set forth in its most recent report of condition
so published. In case at any time the Trustee shall cease to be eligible in
accordance with this Section 11.7, the Trustee shall resign immediately in the
manner and with the effect specified in Section 11.8.

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       SECTION 11.8 Resignation and Removal of Trustee; Appointment of
Successor.

       (a) The Trustee, or any trustee or trustees hereafter appointed, may at
any time resign with respect to any one or more or all series of Bonds by
giving written notice to the Issuer and by giving notice of such resignation
to the Holders of Bonds in the manner provided in Section 1.5.

       (b) In case at any time any of the following shall occur with respect to
any series of Bonds:

       (1) the Trustee shall fail to comply with the provisions of Section
   310(b) of the Trust Indenture Act, after written request thereafter by the
   Issuer or by any Security holder who has been a bona fide Holder of a Bond or
   Bonds for at least six months,

       (2) the Trustee shall cease to be eligible under Section 11.7 and shall
   fail to resign after written request therefor by the Issuer or by any Holder
   of a Bond or Bonds of such Series, or

       (3) the Trustee shall become incapable of acting, or shall be adjudged
   bankrupt or insolvent, or a receiver of the Trustee or of its property shall
   be appointed, or any public officer shall take charge or control of the
   Trustee or of its property or affairs for the purpose of rehabilitation,
   conservation or liquidation;

then, in any such case, (A) the Issuer may remove the Trustee with respect to
the applicable series of Bonds, and appoint a successor trustee by written
instrument, in duplicate, executed by order of the Board of Directors of the
Issuer, or (B) subject to the requirements of Section 315(e) of the Trust
Indenture Act, any Holder who has been a bona fide Holder of a Bond or Bonds of
any such series for at least six months may, on behalf of himself and all others
similarly situated, petition any court of competent jurisdiction for the removal
of the Trustee and the appointment of a successor Trustee with respect to such
series of Bonds. Such court may thereupon after such notice, if any, as it may
deem proper and prescribe, remove the Trustee and appoint a successor Trustee
with respect to such series of Bonds.

       (c) The Holders of a majority in aggregate principal amount of the Bonds
at the time Outstanding may at any time remove the Trustee and appoint a
successor Trustee by delivering to the Trustee so removed, to the successor
Trustee so appointed and to the Issuer, the evidence provided for in Section
11.1 of the action taken by the Holders, provided that unless a Default or Event
of Default shall have occurred and be continuing, the Issuer shall consent (such
consent not to be unreasonably withheld).

       (d) If the Trustee shall resign, be removed, or become incapable of
acting or if a vacancy shall occur in the office of Trustee with respect to
Bonds of any series for any cause, the Issuer shall promptly appoint a successor
Trustee or Trustees with respect to the applicable series of Bonds by written
instrument, in duplicate, executed by order of the Board of Directors of the
Issuer, one copy of which instrument shall be delivered to the former Trustee
and one copy to the successor Trustee. If no successor Trustee shall have been
so appointed with respect to a particular series and have accepted such
appointment pursuant to Section 11.9 within 30 days after the mailing of such
notice of resignation or removal, the former Trustee may petition any

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court of competent jurisdiction for the appointment of a successor Trustee, or
any Holder who has been a bona fide Holder of a Bond or Bonds of the applicable
series for at least six months may, subject to the requirements of Section
315(e) of the Trust Indenture Act, on behalf of himself and all others similarly
situated, petition any such court for the appointment of a successor Trustee.
Such court may thereupon after such notice, if any, as it may deem proper and
prescribe, appoint a successor Trustee.

       (e) Any resignation or removal of the Trustee and any appointment of a
successor Trustee pursuant to this Section shall become effective only upon
acceptance of appointment by the successor Trustee as provided in Section 11.9.

       SECTION 11.9 Acceptance of Appointment by Successor Trustee. Any
successor Trustee appointed under Section 11.8 shall execute, acknowledge and
deliver to the Issuer and to its predecessor Trustee with respect to any or all
applicable series of Bonds an instrument accepting such appointment hereunder,
and thereupon the resignation or removal of the predecessor Trustee shall become
effective and such successor Trustee, without any further act, deed or
conveyance, shall become vested with all the rights, powers, trusts, duties and
obligations with respect to such series of its predecessor Trustee hereunder,
with like effect as if originally named as Trustee herein; but, nevertheless, on
the written request of the Issuer or of the successor Trustee, the Trustee
ceasing to act shall, upon payment of any such amounts then due it pursuant to
the provisions of Section 11.5, execute and deliver an instrument transferring
to such successor Trustee all the rights, powers and trusts with respect to such
series of the Trustee so ceasing to act. Upon request of any such successor
Trustee, the Issuer shall execute any and all instruments in writing for more
fully and certainly vesting in and confirming to such successor Trustee all such
rights and powers. Any Trustee ceasing to act shall, nevertheless, retain a lien
upon all property or funds held or collected by such Trustee to secure any
amounts then due it pursuant to Section 11.5.

       In the case of the appointment hereunder of a successor Trustee with
respect to the Bonds of one or more (but not all) series, the Issuer, the
predecessor Trustee and each successor Trustee with respect to the Bonds of any
applicable series shall execute and deliver an indenture supplemental hereto
which shall contain such mutually agreeable provisions as shall be deemed
necessary or desirable to confirm that all the rights, powers, trusts and duties
of the predecessor Trustee with respect to the Bonds of any series as to which
the predecessor Trustee is not retiring shall continue to be vested in the
predecessor Trustee, and shall, by mutual agreement, add to or change any of the
provisions of this Indenture as shall be necessary to provide for or facilitate
the administration of the trusts hereunder by more than one Trustee, it being
understood that nothing herein or in such supplemental indenture shall
constitute such Trustees co-Trustees of the same trust and that each such
Trustee shall be Trustee of a trust or trusts hereunder separate and apart from
any trust or trusts hereunder administered by any other such Trustee.

       No successor Trustee with respect to any series of Bonds shall accept
appointment as provided in this Section unless at the time of such acceptance
such successor Trustee shall with respect to such series be eligible under
Section 11.7.

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       Upon acceptance of appointment by a successor Trustee with respect to
the Bonds of any series, the Issuer shall give notice of the succession of such
Trustee hereunder to the Holders of Bonds in the manner provided in Section 1.5.
If the Issuer fails to give such notice within 10 days after acceptance of
appointment by the successor Trustee, the successor Trustee shall cause such
notice to be given at the expense of the Issuer.

       SECTION 11.10 Merger, Conversion or Consolidation of Trustee. Any Person
into which the Trustee may be merged or converted or with which it may be
consolidated, or any corporation resulting from any merger, conversion or
consolidation to which the Trustee shall be a party, or any Person succeeding to
all or substantially all the corporate trust business of the Trustee, shall be
the successor of the Trustee hereunder without the execution or filing of any
paper or any further act on the part of any of the parties hereto, provided that
such successor Trustee shall be qualified under the Trust Indenture Act and
eligible under the provisions of Section 11.7 hereof and Section 310(a) of the
Trust Indenture Act.

       In case at the time such successor to the Trustee shall succeed to the
trusts created by this Indenture, any of the Bonds shall have been authenticated
but not delivered, any such successor to the Trustee may adopt the certificate
of authentication of any predecessor Trustee and deliver such Bonds so
authenticated and, in case at that time any of the Bonds shall not have been
authenticated, any successor to the Trustee may authenticate such Bonds either
in the name of any predecessor hereunder or in the name of the successor
trustee, and in such cases such certificate shall have the full force which it
is anywhere in the Bonds or in this Indenture provided that the certificate of
the Trustee shall have; provided that the right to adopt the certificate of
authentication of any predecessor Trustee or the authenticate Bonds in the name
of any predecessor Trustee shall apply only to its successor or successors by
merger, conversion or consolidation.

       SECTION 11.11 Maintenance of Offices and Agencies.

       (a) There shall at all times be maintained in the Borough of Manhattan,
the City of New York, and in such other Places of Payment, if any, as shall be
specified for the Bonds of any series in the related Series Supplemental
Indenture, an office or agency where Bonds may be presented or surrendered for
registration of transfer or exchange and for payment of principal, premium, if
any, and interest. Such office shall be initially:

       The Chase Manhattan Bank
       450 W. 33rd Street
       New York, NY  10001

Notices and demands to or upon the Trustee in respect of the Bonds or this
Indenture may be served at the Corporate Trust Office. Written notice of the
location of each of such other office or agency and of any change of location
thereof shall be given by the Issuer to the Trustee and by the Trustee to the
Holders in the manner specified in Section 1.5. In the event that no such office
or agency shall be maintained or no such notice of location or of change of
location shall be given, presentations, surrenders and demands may be made and
notices may be served at the Corporate Trust Office.

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       (b) There shall at all times be a Security Registrar and a Paying Agent
hereunder. In addition, at any time when any Bonds remain Outstanding, the
Trustee may appoint an Authenticating Agent or Agents with respect to the Bonds
of one or more series which shall be authorized to act on behalf of the Trustee
to authenticate Bonds of such series issued upon original issuance, exchange,
registration of transfer or partial redemption thereof or pursuant to Section
2.9, and Bonds so authenticated shall be entitled to the benefits of this
Indenture and shall be valid and obligatory for all purposes as if authenticated
by the Trustee hereunder (it being understood that wherever reference is made in
this Indenture to the authentication and delivery of Bonds by the Trustee or the
Trustee's certificate of authentication, such reference shall be deemed to
include authentication and delivery on behalf of the Trustee by an
Authenticating Agent and a certificate of authentication executed on behalf of
the Trustee by an Authenticating Agent). If an appointment of an Authenticating
Agent with respect to the Bonds of one or more series shall be made pursuant to
this Section 11.11(b), the Bonds of such series may have endorsed thereon, in
addition to the Trustee's certificate of authentication, an alternate
certificate of authentication in the following form:

       This Bond is one of the series of Bonds referred to in the
within-mentioned Indenture.

                                        ---------------------------------
                                                  Trustee

                                        By
                                          -------------------------------
                                                  Authenticating Agent

                                        By
                                          -------------------------------
                                                  Authorized Signatory

       Any Authorized Agent shall be a bank or trust company, shall be a Person
organized and doing business under the laws of the United States or any State
thereof, with a combined capital and surplus of at least $100,000,000, and shall
be authorized under such laws to exercise corporate trust powers, subject to
supervision by United States Federal or state authorities. If such Authorized
Agent publishes reports of its condition at least annually, pursuant to law or
to the requirements of the aforesaid supervising or examining authority, then
for the purposes of this Section 11.11, the combined capital and surplus of such
Authorized Agent shall be deemed to be its combined capital and surplus as set
forth in its most recent report of condition so published. If at any time an
Authorized Agent shall cease to be eligible in accordance with the provisions of
this Section 11.11, such Authorized Agent shall resign immediately in the manner
and with the effect specified in this Section 11.11.

       The Trustee at its office specified in the first paragraph of this
Indenture, is hereby appointed as Paying Agent and Security Registrar hereunder.

       (c) Any Paying Agent (other than the Trustee) from time to time appointed
hereunder shall execute and deliver to the Trustee an instrument in which said
Paying Agent shall agree with the Trustee, subject to the provisions of this
Section 11.11, that such Paying Agent will:

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       (i) hold all sums held by it for the payment of principal of, and
   premium, if any, and interest on Bonds in trust for the benefit of the
   Persons entitled thereto until such sums shall be paid to such Persons or
   otherwise disposed of as herein provided;

       (ii) give the Trustee within five days thereafter notice of any default
   by any obligor upon the Bonds in the making of any such payment of principal,
   premium, if any, or interest; and

       (iii) at any time during the continuance of any such default, upon the
   written request of the Trustee, forthwith pay to the Trustee all sums so held
   in trust by such Paying Agent.

       Notwithstanding any other provision of this Indenture, any payment
required to be made to or received or held by the Trustee may, to the extent
authorized by written instructions of the Trustee, be made to or received or
held by a Paying Agent in the Borough of Manhattan, the City of New York, for
the account of the Trustee.

       (d) Any Person into which any Authorized Agent may be merged or converted
or with which it may be consolidated, or any Person resulting from any merger,
consolidation or conversion to which any Authorized Agent shall be a party, or
any corporation succeeding to the corporate trust business of any Authorized
Agent, shall be the successor of such Authorized Agent hereunder, if such
successor Person is otherwise eligible under this Section 11.11, without the
execution or filing of any paper or any further act on the part of the parties
hereto or such Authorized Agent or such successor Person.

       (e) Any Authorized Agent may at any time resign by giving written notice
of resignation to the Trustee and the Issuer. The Issuer may, and at the request
of the Trustee shall, at any time, terminate the agency of any Authorized Agent
by giving written notice of such termination to the Authorized Agent and to the
Trustee. Upon the resignation or termination of an Authorized Agent or in case
at any time any such Authorized Agent shall cease to be eligible under this
Section 11.11 (when, in either case, no other Authorized Agent performing the
functions of such Authorized Agent shall have been appointed), the Issuer shall
promptly appoint one or more qualified successor Authorized Agents approved by
the Trustee to perform the functions of the Authorized Agent which has resigned
or whose agency has been terminated or who shall have ceased to be eligible
under this Section 11.11. The Issuer shall give written notice of any such
appointment to all Holders as their names and addresses appear on the Security
Register.

       SECTION 11.12 Reports by Trustee. On or before March 15 in every year, so
long as any Bonds are Outstanding hereunder, the Trustee shall transmit to the
Holders a brief report, dated as of the preceding December 31, to the extent
required by Section 313 of the Trust Indenture Act in accordance with the
procedures set forth in said Section. A copy of such report at the time of its
mailing to Holders shall be filed with the SEC and each stock exchange, if any,
on which the Bonds are listed. The Issuer shall promptly notify the Trustee if
the Bonds become listed on any stock exchange, and the Trustee shall comply with
Section 313(d) of the Trust Indenture Act.

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       SECTION 11.13 Trustee Risk. None of the provisions contained in this
Indenture shall require the Trustee to expend or risk its own funds or otherwise
incur personal financial liability in the performance of any of its duties or in
the exercise of any of its rights or powers, if it shall have reasonable ground
for believing that the repayment of such funds or liability is not reasonably
assured to it. Whether or not expressly provided herein, every provision of this
Indenture relating to the conduct or affecting the liability of or affording
protection to the Trustee shall be subject to Section 11.1 and the requirements
of the Trust Indenture Act.

       SECTION 11.14 Appointment of Co-Trustee. It is the purpose of this
Indenture that there shall be no violation of any law of any jurisdiction,
denying or restricting the right of banking corporations or associations to
transact business as Trustee in such jurisdiction. It is recognized that in case
of litigation under this Indenture or any Transaction Document, and in
particular in case of the enforcement of any such document on default, or in
case the Trustee deems that by reason of any present or future law of any
jurisdiction it may not exercise any of the powers, rights or remedies herein
granted to the Trustee or hold title to the properties, in trust, as herein
granted, or take any other action which may be desirable or necessary in
connection therewith, it may be necessary that the Trustee appoint an additional
individual or institution as a separate or co-trustee. The following provisions
of this Section 11.14 are adopted to these ends.

       SECTION 11.15 Knowledge of Default. In no event shall the Trustee be
deemed to have knowledge of an Event of Default unless it has received written
notice or a Responsible Officer has actual knowledge thereof.

       In the event that the Trustee appoints an additional individual or
institution as a separate or co-trustee, each and every remedy, power, right,
claim, demand, cause of action, immunity, estate, title, interest and lien
expressed or intended by this Indenture to be exercised by or vested in or
conveyed to the Trustee with respect thereto shall be exercisable by and vested
in such separate or co-trustee but only to the extent necessary to enable such
separate or co-trustee to exercise such powers, rights and remedies, and every
covenant and obligation necessary to the exercise thereof by such separate or
co-trustee shall run to and be enforceable by either of them.

       Should any instrument in writing be required by the separate trustee or
co-trustee so appointed by the Trustee for more fully and certainly vesting in
and confirming to him or it such properties, rights, powers, trusts, duties and
obligations, any and all such instruments in writing shall, on request, be
executed, acknowledged and delivered by the Issuer. In case any separate trustee
or co-trustee, or a successor to either, shall die, become incapable of acting,
resign or be removed, all the estates, properties, rights, powers, trusts,
duties and obligations of such separate trustee or co-trustee, so far as
permitted by law, shall vest in and be exercised by the Trustee until the
appointment of a new trustee or successor to such separate trustee or
co-trustee.

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                                   ARTICLE 12

                             CONCERNING THE HOLDERS

       SECTION 12.1 Acts of Holders.

       (a) Any request, demand, authorization, direction, notice, consent,
waiver or other action provided by this Indenture to be given or taken by
Holders (collectively, an "Act" of such Holders, which term also shall refer to
the instruments or record evidencing or embodying the same) may be embodied in
and evidenced by one or more instruments of substantially similar tenor signed
by such Holders in person or by an agent duly appointed in writing or,
alternatively, may be embodied in and evidenced by the record of Holders of
Bonds voting in favor thereof, either in person or by proxies duly appointed in
writing, at any meeting of Holders of Bonds duly called and held in accordance
with the provisions of Article 13, or a combination of such instruments and any
such record. Except as herein otherwise expressly provided, such action shall
become effective when such instrument or instruments or record, or both, are
delivered to the Trustee, and when it is specifically required herein, to the
Issuer. Proof of execution of any such instrument or of a writing appointing any
such agent shall be sufficient for any purpose of this Indenture and (subject to
Section 11.1) conclusive in favor of the Trustee and the Issuer, if made in the
manner provided in this Section 12.1. The record of any meeting of Holders of
Bonds shall be proved in the manner provided in Section 13.6.

       (b) The fact and date of the execution by any Person of any such
instrument or writing may be proved by the certificate of any public or other
officer of any jurisdiction authorized to take acknowledgments of deeds or
administer oaths that the Person executing such instrument acknowledged to such
officer the execution thereof, or by an affidavit of a witness to such execution
sworn to before any such notary or other such officer, and where such execution
is by an officer of a corporation or association or of a Issuer, on behalf of
such corporation, association or Issuer, such certificate or affidavit shall
also constitute sufficient proof of such Person's authority. The fact and date
of the execution of any such instrument or writing, or the authority of the
Person executing the same, may also be proved in any other manner which the
Trustee deems sufficient.

       (c) The principal amount and serial numbers of Bonds held by any Person,
and the date or dates of holding the same, shall be proved by the Security
Register and the Trustee shall not be affected by notice to the contrary.

       (d) Any Act by the Holder of any Bond (i) shall bind every future Holder
of the same Bond and the Holder of every Bond issued upon the transfer thereof
or the exchange therefor or in lieu thereof, whether or not notation of such
action is made upon such Bond, and (ii) shall be valid notwithstanding that such
Act is taken in connection with the transfer of such Bond to any other Person,
including the Issuer or any Affiliate thereof.

       (e) Until such time as written instruments shall have been delivered with
respect to the requisite percentage of principal amount of Bonds for the Act
contemplated by such instruments, any such instrument executed and delivered by
or on behalf of a Holder of Bonds may be revoked with respect to any or all of
such Bonds by written notice by such Holder (or its

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                                      -78-

duly appointed agent) or any subsequent Holder (or its duly appointed agent),
proven in the manner in which such instrument was proven unless such instrument
is by its terms expressly irrevocable.

       (f) Bonds of any series authenticated and delivered after any Act of
Holders may, and shall if required by the Issuer, bear a notation in form
approved by the Issuer as to any action taken by such Act of Holders. If the
Issuer shall so determine, new Bonds of any series so modified as to conform, in
the opinion of the Issuer, to such action, may be prepared and executed by the
Issuer and authenticated and delivered by the Trustee in exchange for
outstanding Bonds of such series.

       The Issuer may, but shall not be obligated to, fix a record date for the
purpose of determining the Holders entitled to sign any instrument evidencing or
embodying an Act of the Holders. If a record date is fixed, those Persons who
were Holders at such record date (or their duly appointed agents), and only
those Persons, shall be entitled to sign any such instrument evidencing or
embodying an Act of Holders or to revoke any such instrument previously signed,
whether or not such Persons continue to be Holders after such record date. No
such instrument shall be valid or effective if signed more than 90 days after
such record date, and may be revoked as provided in paragraph (e) above.

       SECTION 12.2 Bonds Owned by Issuer and Affiliates Deemed Not Outstanding.
In determining whether the Holders of the requisite aggregate principal amount
of Bonds have concurred in any request, demand, authorization, direction,
notice, consent and waiver or other act under this Indenture, Bonds which are
owned by the Issuer, any Partner or any Affiliate of any of the foregoing shall
be disregarded and deemed not to be Outstanding for the purpose of any such
determination except that for the purposes of determining whether the Trustee
shall be protected in relying on any such direction, consent or waiver, only
Bonds for which a Responsible Officer of the Trustee has received written notice
of such ownership as conclusively evidenced by the Security Register shall be so
disregarded. The Issuer shall furnish the Trustee, upon its reasonable request,
with a list of such Affiliates. Bonds so owned which have been pledged in good
faith may be regarded as Outstanding for the purposes of this Section, if the
pledgee shall establish to the satisfaction of the Trustee that the pledgee has
the right to vote such Bonds and that the pledgee is not an Affiliate of the
Issuer. Subject to the provisions of Section 315 of the Trust Indenture Act, in
case of a dispute as to such right, any decision by the Trustee, taken upon the
advice of counsel, shall be full protection to the Trustee.

                                   ARTICLE 13

                                HOLDERS' MEETINGS

       SECTION 13.1 Purposes for Which Holders' Meetings May Be Called. A
meeting of Holders may be called at any time and from time to time pursuant to
this Article 13 for any of the following purposes:

       (a) to give any notice to the Issuer or to the Trustee, or to give any
   directions to the Trustee, or to waive or to consent to the waiving of any
   default hereunder and its

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                                      -79-

   consequences, or to take any other action authorized to be taken by
   Holders pursuant to Article 10;

       (b) to remove the Trustee and appoint a successor Trustee pursuant to
   Article 11;

       (c) to consent to the execution of an indenture or indentures
   supplemental hereto pursuant to Section 14.2; or

       (d) to take any other action authorized to be taken by or on behalf of
   the Holders of any specified aggregate principal amount of the Bonds under
   any other provision of this Indenture or under applicable law.

       SECTION 13.2 Issuer and Holders May Call Meeting. In case the Issuer,
pursuant to a Board Resolution, or the Holders of at least 10% in aggregate
principal amount of the Bonds of any series then Outstanding shall have
requested the Trustee to call a meeting of Holders of such series, by written
request setting forth in general terms the action proposed to be taken at the
meeting, and the Trustee shall not have made the mailing of the notice of such
meeting within 20 days after receipt of such request, then the Issuer or the
Holders of such Bonds in the amount above specified may determine the time and
the place in the Borough of Manhattan, The City of New York, for such meeting
and may call such meeting to take any action authorized in Section 13.1 by
giving notice thereof as provided in Section 13.2.

       SECTION 13.3 Persons Entitled to Vote at Meeting. To be entitled to vote
at any meeting of Holders a person shall be (a) Holder of one or more Bonds with
respect to which such meeting is being held or (b) a person appointed by an
instrument in writing as proxy for the Holder or Holders of such Bonds by a
Holder of one or more such Bonds. The only persons who shall be entitled to be
present or to speak at any meeting of Holders shall be the persons entitled to
vote at such meeting and their counsel and any representatives of the Trustee
and its counsel and any representatives of the Issuer and its counsel.

       SECTION 13.4 Determination of Voting Rights; Conduct and Adjournment of
Meeting. Notwithstanding any other provisions of this Indenture, the Trustee may
make such reasonable regulations as it may deem advisable for any meeting of
Holders, in regard to proof of the holding of Bonds and of the appointment of
proxies, and in regard to the appointment and duties of inspectors of votes, the
submission and examination of proxies, certificates and other evidence of the
right to vote, and such other matters concerning the conduct of the meeting as
it shall think fit. Such regulations may provide that written instruments
appointing proxies, regular on their face, may be presumed valid and genuine
without the proof specified in Section 12.1 or other proof. Except as otherwise
permitted or required by any such regulations, the holding of Bonds shall be
proved in the manner specified in Section 12.1 and the appointment of any proxy
shall be proved in the manner specified in said Section 12.1 or by having the
signature of the person executing the proxy witnessed or guaranteed by any bank,
banker, trust company or firm satisfactory to the Trustee.

       The Issuer or the Holders calling the meeting, as the case may be, shall
appoint a temporary chairman. A permanent chairman and a permanent secretary of
the meeting shall be

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                                      -80-

elected by vote of the Holders of a majority in aggregate principal amount of
the Bonds represented at the meeting and entitled to vote.

       Subject to the provisions of Section 12.2, at any meeting each Holder of
a series or proxy shall be entitled to one vote for each $1,000 principal amount
of Bonds of such series held or represented by him; provided, however, that no
vote shall be cast or counted at any meeting in respect of any Bond challenged
as not Outstanding and ruled by the chairman of the meeting to be not
Outstanding. The chairman of the meeting shall have no right to vote other than
by virtue of Bonds of such series held by him or instruments in writing as
aforesaid duly designating him as the person to vote on behalf of other Holders
of such series. Any meeting of Holders duly called pursuant to Section 13.2 may
be adjourned from time to time, and the meeting may be held as so adjourned
without further notice. At any meeting, the presence of persons holding or
representing Bonds with respect to which such meeting is being held in an
aggregate principal amount sufficient to take action upon the business for the
transaction of which such meeting was called shall be necessary to constitute a
quorum; but, if less than a quorum be present, the persons holding or
representing a majority of the Bonds represented at the meeting may adjourn such
meeting with the same effect, for all intents and purposes, as though a quorum
had been present.

       SECTION 13.5 Counting Votes and Recording Action of Meeting. The vote
upon any resolution submitted to any meeting of Holders of a series shall be by
written ballots on which shall be subscribed the signatures of the Holders of
Bonds of such series or of their representatives by proxy and the serial numbers
and principal amounts of the Bonds of such series held or represented by them.
The permanent chairman of the meeting shall appoint two inspectors of votes who
shall count all votes cast at the meeting for or against any resolution and who
shall make and file with the secretary of the meeting their verified written
reports in duplicate of all votes cast at the meeting. A record in duplicate of
the proceedings of each meeting of Holders shall be prepared by the secretary of
the meeting and there shall be attached to said record the original reports of
the inspectors of votes on any vote by ballot taken thereat and affidavits by
one or more persons having knowledge of the facts setting forth a copy of the
notice of the meeting. The record shall show the serial numbers of the Bonds
voting in favor of or against any resolution. The record shall be signed and
verified by the affidavits of the permanent chairman and secretary of the
meeting and one of the duplicates shall be delivered to the Issuer and the other
to the Trustee to be preserved by the Trustee, the latter to have attached
thereto the ballots voted at the meeting.

       Any record so signed and verified shall be conclusive evidence of the
matters therein stated.

                                   ARTICLE 14

                             SUPPLEMENTAL INDENTURES

       SECTION 14.1 Supplemental Indentures Without Consent of Holders. Without
the consent of the Holders of any Bonds, the Issuer, when authorized by a Board
Resolution (a copy of which shall be delivered to the Trustee), and the Trustee,
at any time and from time to

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time, may enter into one or more indentures supplemental hereto in form
satisfactory to the Trustee or enter into any consent with respect to the
Collateral Documents for any of the following purposes:

       (a) to establish the form and terms of Bonds of any series permitted by
   Sections 2.1 and 2.3; or

       (b) to evidence the succession of another entity to the Issuer and the
   assumption by any such successor of the covenants of the Issuer herein
   contained; or

       (c) to evidence the succession of a new Trustee hereunder pursuant to
   Section 11.9; or

       (d) to add to the covenants of the Issuer such further covenants,
   restrictions, conditions or provisions as the Board of Directors shall
   consider to be for the protection of the Holders of Bonds, and to make the
   occurrence, or the occurrence and continuance of a default in any such
   additional covenants, restrictions, conditions or provisions an Event of
   Default permitting the enforcement of all or any of the several remedies
   provided in this Indenture as herein set forth; provided that in respect of
   any such additional covenant, restriction, condition or provision such
   supplemental indenture may provide for a particular period of grace after
   default (which period may be shorter or longer than that allowed in the case
   of other defaults) or may provide for immediate enforcement upon such an
   Event of Default or may limit the remedies available to the Trustee due
   solely to such an Event of Default or may limit the right of the Holders of a
   majority in aggregate principal amount of the Bonds to waive such an Event of
   Default; or

       (e) to convey, transfer and assign to the Trustee properties or assets to
   secure the Bonds, and to correct or amplify the description of any property
   at any time subject to this Indenture or the Collateral Documents or to
   assure, convey and confirm unto the Trustee any property subject or required
   to be subject to this Indenture or the Collateral Documents; or

       (f) to modify, eliminate or add to the provisions of this Indenture to
   such extent as shall be necessary to qualify, requalify or continue the
   qualification of this Indenture (including any supplemental indenture) under
   the Trust Indenture Act, or under any similar United States Federal statute
   hereafter enacted, and to add to this Indenture such other provisions as may
   be expressly permitted by the Trust Indenture Act, excluding, however, the
   provisions referred to in Section 316(a)(2) of the Trust Indenture Act as in
   effect at the date as of which this instrument was executed or any
   corresponding provision in any similar United States Federal statute
   hereafter enacted; or

       (g) to permit or facilitate the issuance of Bonds in uncertificated form;
   or

       (h) to change or eliminate any provision of this Indenture or the
   Collateral Documents; provided, however, that if such change or elimination
   shall adversely affect the interests of the Holders of Bonds of any series,
   such change or elimination shall not become effective with respect to such
   series; or

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                                     -82-

       (i) to cure any ambiguity, to correct or supplement any provision in the
   Indenture or the Collateral Documents that may be defective or inconsistent
   with any other provision herein, or to make any other provisions with respect
   to matters or questions arising under this Indenture or the Collateral
   Documents, provided such action shall not adversely affect the interest of
   the Holders of any series in any material respect; or

       (j) to provide for the issuance of exchange securities, as contemplated
   by the Registration Rights Agreement, and to make such other changes to the
   Indenture or the Collateral Documents as the Board of Directors of the Issuer
   determines are necessary or appropriate in connection therewith, provided
   such action shall not adversely affect the interests of the Holders of Bonds
   of any series in any material respect.

       SECTION 14.2 Supplemental Indenture with Consent of Holders. With the
consent of the Majority Holders of Bonds of all series then Outstanding,
considered as one class, by Act of said Holders delivered to the Issuer and the
Trustee, the Issuer, when authorized by a Board Resolution (a copy of which
shall be delivered to the Trustee), may, and the Trustee, subject to Sections
14.3 and 14.4, shall, enter into an indenture or indentures supplemental hereto
for the purpose of adding any mutually agreeable provisions to or changing in
any manner or eliminating any of the provisions of, this Indenture; provided,
however, that if there shall be Bonds of more than one series Outstanding
hereunder and if a proposed supplemental indenture shall directly affect the
rights of the Holders of one or more, but less than all, of such series, then
the consent only of the Holders of not less than a Majority in aggregate
principal amount of the Outstanding Bonds of all series so directly affected,
considered as one class, shall be required; and provided, further, that no such
supplemental indenture shall, without the consent of the Holder of each
Outstanding Bond directly affected thereby,

       (a) change any Scheduled Payment Date, or the dates or circumstances of
   payment of premium, if any, on any Bond, or change the principal amount
   thereof or the interest thereon or any premium payable upon the redemption
   thereof, or change the place of payment where, or the coin or currency in
   which, any Bond or the premium, if any, or the interest thereon is payable,
   or impair the right to institute suit for the enforcement of any such payment
   of principal or interest on or after the Scheduled Payment Date for such
   payment (or, in the case of redemption, on or after the Redemption Date) or
   such payment of premium, if any, on or after the date such premium becomes
   due and payable in respect of such Bonds; or

       (b) except to the extent expressly permitted by this Indenture or any of
   the Collateral Documents, permit the creation of any Lien prior to or, except
   as contemplated by Section 6.16, pari passu with the Lien of the Collateral
   Documents with respect to any of the Collateral, terminate the Lien of the
   Collateral Documents on any Collateral or deprive any Holder of the security
   afforded by the Lien of the Collateral Documents; or

       (c) reduce the percentage in principal amount of the Outstanding Bonds,
   the consent of whose Holders is required for any such supplemental indenture,
   or the consent of whose Holders is required for any waiver of compliance with
   certain provisions of this Indenture or certain defaults hereunder and their
   consequences provided for in this Indenture; or

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       (d) modify any of the provisions of Section 10.12 or of this Section
   14.2.

       A supplemental indenture that changes or eliminates any covenant or other
provision of this Indenture or any Collateral Document which has expressly been
included solely for the benefit of one or more particular series of Bonds, or
which modifies the rights of the Holders of Bonds of such series with respect to
such covenant or other provision, shall be deemed not to affect the rights under
this Indenture of the Holders of Bonds of any other series.

       Upon receipt by the Trustee of Board Resolutions and such other
documentation as the Trustee may reasonably require and upon the filing with the
Trustee of evidence of the Act of said Holders, the Trustee shall join in the
execution of such supplemental indenture or other instrument, as the case may
be, subject to the provisions of Sections 14.3 and 14.4.

       It shall not be necessary for any Act of Holders under this Section to
approve the particular form of any proposed supplemental indenture, but it shall
be sufficient if such Act shall approve the substance thereof.

       SECTION 14.3 Execution of Supplemental Indentures. In executing, or
accepting the additional trusts created by any Series Supplemental Indenture or
other supplemental indenture permitted by this Article 14 or the modifications
thereby of the trusts created by this Indenture, the Trustee shall be entitled
to receive, and (subject to Section 11.1) shall be fully protected in relying
upon, an Opinion of Counsel stating that the execution of such supplemental
indenture is authorized or permitted by this Indenture and all conditions
precedent to the execution of such supplemental indenture have been met.

       SECTION 14.4 Effect of Supplemental Indentures. Upon the execution of any
supplemental indenture under this Article 14, this Indenture shall be modified
in accordance therewith, and such supplemental indenture shall form a part of
this Indenture for all purposes; and every Holder of Bonds theretofore or
thereafter authenticated and delivered hereunder shall be bound thereby.

       SECTION 14.5 Conformity with Trust Indenture Act. Every supplemental
indenture executed pursuant to this Article 14 shall conform to the requirements
of the Trust Indenture Act as then in effect.

       SECTION 14.6 Reference in Bonds to Supplemental Indentures. Bonds
authenticated and delivered after the execution of any supplemental indenture
pursuant to this Article 14 may, and shall if required by the Issuer, bear a
notation in form approved by the Issuer as to any matter provided for in such
supplemental indenture; and, in such case, suitable notation may be made upon
Outstanding Bonds after proper presentation and demand. If the Issuer shall so
determine, new Bonds so modified as to conform, in the opinion of the Issuer and
the Trustee, to any such supplemental indenture may be prepared and executed by
the Issuer and authenticated and delivered by the Trustee in exchange for
Outstanding Bonds.

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                                   ARTICLE 15

                           SATISFACTION AND DISCHARGE

       SECTION 15.1 Satisfaction and Discharge of Bonds. Except as otherwise
provided with respect to the Bonds of any series in the Series Supplemental
Indenture relating thereto, the Bonds of such series shall, on or prior to the
Scheduled Payment Date with respect to the final installment of principal
thereof, be deemed to have been paid for all purposes of this Indenture, and the
entire Debt of the Issuer in respect thereof shall be deemed to have been
satisfied and discharged, upon satisfaction of the following conditions:

       (a) the Issuer shall have irrevocably deposited or caused to be deposited
   with the Trustee, in trust, money in an amount which shall be sufficient to
   pay when due the principal of and premium, if any, and interest due and to
   become due on the Bonds of such series on and prior to the Scheduled Payment
   Date with respect to the final installment of principal thereof or upon
   redemption;

       (b) if any such deposit of money shall have been made prior to the
   Scheduled Payment Date with respect to the final installment of principal or
   the Redemption Date of such Bonds, the Issuer shall have delivered to the
   Trustee a Issuer Order stating that such money shall be held by the Trustee,
   in trust;

       (c) in the case of redemption of Bonds, the Issuer Order with respect to
   such redemption pursuant to Article 8 shall have been given to the Trustee;
   and

       (d) there shall have been delivered to the Trustee an Opinion of Counsel
   to the effect that such satisfaction and discharge of the Debt of the Issuer
   with respect to the Bonds of such series shall not be deemed to be, or result
   in, a taxable event with respect to the Holders of such series for purposes
   of United States federal income taxation unless the Trustee shall have
   received documentary evidence that each Holder of such series either is not
   subject to, or is exempt from, United States federal income taxation.

Upon satisfaction of the aforesaid conditions with respect to the Bonds of any
series, the Trustee shall, upon receipt of a Issuer Order, execute proper
instruments acknowledging satisfaction and discharge of the series of Bonds.

       In the event that Bonds which shall be deemed to have been paid as
provided in this Section 15.1 do not mature and are not to be redeemed within
the 60-day period commencing on the date of the deposit with the Trustee of
moneys, the Issuer shall, as promptly as practicable, give a notice, in the same
manner as a notice of redemption with respect to such Bonds, to the Holders of
such Bonds to the effect that such Bonds are deemed to have been paid and the
circumstances thereof.

       Notwithstanding the satisfaction and discharge of any Bonds as aforesaid,
the obligations of the Issuer and the Trustee in respect of such Bonds under
Sections 2.8, 2.9, 2.10 and 11.5 and this Article 15 shall survive.

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       SECTION 15.2 Satisfaction and Discharge of Indenture. This Indenture
shall upon Issuer Order cease to be of further effect (except as hereinafter
expressly provided), and the Trustee, at the expense of the Issuer, shall
execute proper instruments acknowledging satisfaction and discharge of this
Indenture, when:

       (a) either

           (i) all Bonds theretofore authenticated and delivered (other than (A)
       Bonds which have been destroyed, lost or stolen and which have been
       replaced or paid as provided in Section 2.9 and (B) Bonds deemed to have
       been paid in accordance with Section 15.1) have been delivered to the
       Trustee for cancellation; or

           (ii) all Bonds not theretofore delivered to the Trustee for
       cancellation shall be deemed to have been paid in accordance with
       Section 15.1;

       (b) all other sums due and payable hereunder have been paid; and

       (c) the Issuer has delivered to the Trustee an Officer's Certificate and
   an Opinion of Counsel, each stating that all conditions precedent herein
   provided for relating to the satisfaction and discharge of this Indenture
   have been complied with.

Upon satisfaction of the aforesaid conditions, the Trustee shall, upon receipt
of a Issuer Order, execute proper instruments acknowledging satisfaction and
discharge of the Indenture and take all other action reasonably requested by the
Issuer to evidence the termination of any and all Liens created by or with
respect to this Indenture.

       Notwithstanding the satisfaction and discharge of this Indenture as
aforesaid, the obligations of the Issuer and the Trustee under Sections 2.8,
2.9, 2.10 and 11.5 and this Article 15 shall survive.

       Upon satisfaction and discharge of this Indenture as provided in this
Section 15.2, the Trustee shall assign, transfer and turn over to or upon the
order of the Issuer, any and all money, securities and other property then held
by the Trustee for the benefit of the Holders, other than money deposited with
the Trustee pursuant to Section 15.1(a) and interest and other amounts earned or
received thereon.

       SECTION 15.3 Application of Trust Money. The money deposited with the
Trustee pursuant to Section 15.1 shall not be withdrawn or used for any purpose
other than, and shall be held in trust for, the payment of the principal of and
premium, if any, and interest on the Bonds or portions of principal amount
thereof in respect of which such deposit was made.

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                                   ARTICLE 16

                                   DEFEASANCE

       SECTION 16.1 Defeasance.

       (a) Subject to Sections 16.1(b) and 16.2, the Issuer at any time may
terminate (i) all its obligations under this Indenture, the Bonds and the
Collateral Documents (a "Legal Defeasance") or (ii) any of its covenants, other
than its obligation to make payments on the Bonds pursuant to Section 2.10 (a
"Covenant Defeasance"). With respect to any Covenant Defeasance, except as
specified in clause (ii) of the preceding sentence, the remainder of this
Indenture and the Bonds, shall be unaffected thereby. The Issuer may exercise a
Legal Defeasance notwithstanding the prior exercise of a Covenant Defeasance. If
the Issuer exercises a Legal Defeasance, payment of the Bonds may not be
accelerated due to an Event of Default. Upon satisfaction of the conditions set
forth herein and on demand of the Issuer, the Trustee (x) shall acknowledge in
writing the discharge of the obligations terminated by the Issuer, (y) shall
execute documents and deliver such instruments in writing as shall be required
to reconvey, release, assign and deliver to the Issuer any and all of the
Trustee's interest in the Collateral, the right, title and interest in and to
any and all rights conveyed, assigned or pledged to the Trustee or otherwise
subject to this Indenture, except amounts in the funds required to be paid to
the Issuer under this Indenture, and (z) shall turn over to the Issuer or to any
such person, body or authority as may be entitled to receive the same all
balances then held by it hereunder. Covenant Defeasance, as effected hereby,
means that the Issuer may omit to comply with and shall have no liability in
respect of any term, condition or limitation set forth under any of the
covenants in this Indenture except as set forth hereinabove, whether directly or
indirectly by reason of any reference elsewhere herein to any such covenant or
Section or to any other provision herein or in any other document.

       (b) Notwithstanding Section 16.1(a) above, the obligations of the Issuer
pursuant to Sections 2.8, 2.9, Section 2.10 and 11.5 shall survive until the
Bonds have been paid in full. Thereafter, the obligations of the Issuer pursuant
to Section 11.5 shall survive.

       SECTION 16.2 Conditions to Defeasance. Either the Legal Defeasance or the
Covenant Defeasance may be exercised only if:

       (a) The Issuer shall have irrevocably deposited in trust with the Trustee
   (i) cash in an amount which, when added to any other moneys held by the
   Trustee and available for such payment, would be sufficient to pay (A) the
   principal of, and any premium and interest on, all Bonds issued hereunder and
   under any Series Supplemental Indenture when due, whether on any Scheduled
   Payment Date or upon redemption, acceleration, or otherwise, and (B) all
   other sums payable hereunder and under any Series Supplemental Indenture,
   (ii) non-callable direct obligations of, or obligations guaranteed by, the
   United States, maturing on or before the date or dates when the payments
   specified in clause (i) above shall become due, the principal amount of which
   and the interest thereon, when due, is or will be, in the aggregate,
   sufficient to make all such payments, (iii) securities evidencing ownership
   interest in obligations or in specified portions thereof (which shall consist
   of specified portions of the principal of or interest on such obligations) of
   the

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                                      -87-

    character described in clause (ii), sufficient to make all the payments
    specified in clause (i) above, or (iv) any combination of such cash and
    such obligations (the "Obligations") specified in (ii) or (iii) above, the
    aggregate amount of which and interest thereon, when due, are or will be
    sufficient to make all the payments specified in clause (i) above, and such
    deposit shall not cause the Trustee to have a conflicting interest as
    defined in and for the purposes of the Trust Indenture Act;

           (b) The Issuer shall have delivered to the Trustee a certificate
    from a nationally recognized firm of independent accountants expressing
    their opinion that the deposited cash and/or the Obligations without any
    reinvestment thereof will provide cash at such times and in such amounts as
    will be sufficient to pay principal of, and any premium and interest on,
    all Outstanding Bonds when due, whether at on any Scheduled Payment Date or
    upon redemption, acceleration, or otherwise;

           (c) The Issuer shall have delivered to the Trustee an Opinion of
    Counsel to the effect that (i) all preference periods applicable to the
    defeasance trust have expired under any applicable bankruptcy, insolvency,
    reorganization or similar laws affecting creditors' rights generally, (ii)
    the defeasance trust resulting from the deposit does not constitute, or is
    qualified as, a regulated investment company under the Investment Company
    Act of 1940, as amended, and (iii) the Holders shall have a perfected
    security interest under applicable law in the Obligations so deposited with
    customary assumptions and qualifications;

           (d) No Default or Event of Default shall have occurred and be
    continuing on the date of such deposit or insofar as Events of Default from
    bankruptcy or insolvency events are concerned, at any time in the period
    ending on the 123rd day after the date of deposit;

           (e) Such Legal Defeasance or Covenant Defeasance, as the case may be,
    shall not result in a breach or violation of or constitute a Default under
    this Indenture, or any other material agreement or instrument to which the
    Issuer is a party or by which the Issuer is bound;

           (f) In the case of a Legal Defeasance, the Issuer shall have
    delivered to the Trustee an Opinion of Counsel confirming that (i) the
    Issuer has received from, or there has been published by, the Internal
    Revenue Service a ruling or (ii) since the date of this Indenture there has
    been a change in the applicable United States Federal income tax law, in
    either case to the effect that, and based thereon such Opinion of Counsel
    shall confirm that, the Holders will not recognize income, gain or loss for
    United States Federal income tax purposes as a result of such Legal
    Defeasance and will be subject to United States Federal income tax on the
    same amounts, in the same manner and at the same times as would have been
    the case if such Legal Defeasance had not occurred;

           (g) In the case of a Covenant Defeasance, the Issuer shall have
    delivered to the Trustee an Opinion of Counsel reasonably acceptable to the
    Trustee confirming that the Holders will not recognize income, gain or loss
    for United States Federal income tax purposes as a result of such Covenant
    Defeasance and will be subject to United States

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<PAGE>   96

                                      -88-

    Federal income tax on the same amounts, in the same manner and at the same
    times as would have been the case if such Covenant Defeasance had not
    occurred; and

        (h) The Issuer shall have delivered to the Trustee an Officer's
    Certificate and Opinion of Counsel, each stating that all conditions
    precedent provided for relating to either the Legal Defeasance or the
    Covenant Defeasance, as the case may be, have been complied with.

        Neither the Obligations nor moneys deposited with the Trustee pursuant
to this section shall be substituted, withdrawn, reinvested or used for any
purpose other than, and shall be segregated and held in trust for the  payment
of the principal of, and premium, if any and interest on, the Bonds.

                                   ARTICLE 17

                             LIMITATION ON LIABILITY

       SECTION 17.1 Limitation on Liability. Notwithstanding anything to the
contrary contained in this Indenture or the Bonds or the Collateral Documents,

       (a) the liability and obligation of the Issuer to perform and observe and
   make good the obligations contained in this Indenture and the Bonds and the
   Collateral Documents and to pay the Indebtedness issued hereunder in
   accordance with the provisions of this Indenture and the Bonds (such
   liability and obligation being herein referred to as the "Issuer's
   Obligations"), or any part thereof, or any claim based thereon or otherwise
   in respect thereof shall not (except as expressly provided in clause (b)
   below or in the last paragraph of this Section 17.1) be enforced by any
   action or proceeding wherein damages or any money judgment or any deficiency
   judgment or any judgment establishing any personal obligation or liability
   shall be sought, collected or otherwise obtained against any Member, any
   parent of a Member or any past, present or future partner, officer, director,
   shareholder, incorporator, Affiliate or related Person, of any Member or the
   Issuer (each such Member, parent of a Member and past, present or future
   partner, officer, director or shareholder, incorporator, Affiliate or related
   Person being herein referred to as a "Related Person"), and (except as
   expressly provided in clause (b) below or in the last paragraph of this
   Section 17.1) each of the Trustee, the Holders and any Person acting on
   behalf of the Trustee or the Holders, for itself and its successors and
   assigns, irrevocably waives any and all right to sue for, seek or demand any
   such damages, money judgment, deficiency judgment or personal judgment
   against any Related Person under or by reason of or in connection with the
   Issuer's Obligations, or any part thereof, or any claim based thereon or
   otherwise in respect thereof and (except as expressly provided in clause (b)
   below or in the last paragraph of this Section 17.1) agrees to look solely to
   the Issuer and Collateral held under or in connection with the Collateral
   Documents for the enforcement of the Issuer's Obligations; and

       (b) The liability of the Related Persons with respect to the Issuer's
   Obligations, or any part thereof, or for any claim based thereon or otherwise
   in respect thereof is (except

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                                      -89-

   as expressly provided in the last paragraph of this Section 17.1) limited
   to the respective interests of such Related Persons in the Collateral, and
   (except as expressly provided in the last paragraph of this Section 17.1) no
   recourse shall be had in the event of any non-performance by the Issuer of
   any of the Issuer's Obligations to (i) any assets or properties of any
   Related Person other than the respective interests of such Related Persons in
   the Collateral or (ii) the Related Persons (except with respect to the
   respective interests of such Related Persons in the Collateral), and no
   judgment for any deficiency upon the Issuer's Obligations, or any part
   thereof, or for any claim based thereon or otherwise in respect thereof or
   related thereto, shall be obtainable by the Holders, the Trustee or any
   Person acting on behalf of the Holders or the Trustee against any Related
   Person.

       Nothing contained in this Section 17.1 shall be construed (i) as
preventing the Trustee, the Holders and any Person acting on behalf of the
Trustee or the Holders from naming the Issuer or a Related Person in any action
or proceeding brought by the Trustee, the Holders and any Person acting on
behalf of the Trustee or the Holders to enforce and to realize upon or the
Collateral purported to be provided by such Related Persons under or in
connection with the Collateral Documents so long as no judgment, order, decree
or other relief in the nature of a personal or deficiency judgment or otherwise
establishing any personal obligation under or by reason of or in connection with
the Issuer's Obligations, or any part thereof, or any claim based thereon or
otherwise in respect thereof shall be asked for, taken, entered or enforced
against any Related Person, in any such action or proceeding, (ii) as modifying,
qualifying or affecting in any manner whatsoever the Lien and security interests
created by this Indenture and the Collateral Documents and the other Transaction
Documents or the enforcement thereof by the Holders or the Trustee or any Person
acting on behalf of the Holders or the Trustee, (iii) as modifying, qualifying
or affecting in any manner whatsoever the personal recourse undertakings,
obligations and liabilities of any Person (including, without limitation, any
Related Person) under any capital contribution agreement, any guaranty of
payment, completion guaranty or any guaranty or indemnification agreement now or
hereafter executed and delivered to the Trustee, the Holders or any Person
acting on behalf of the Trustee or the Holders in connection with the
transactions contemplated by this Indenture or (iv) as modifying, qualifying or
affecting in any manner whatsoever the personal recourse liability of any
Related Person, or any other Person for fraud or willful misrepresentation or
any wrongful misappropriation or diversion of any portion of the Collateral.

                       NRG Northeast Generating Indenture
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<PAGE>   98

                                      -90-

         IN WITNESS WHEREOF, the parties have caused this Indenture to be duly
executed by their respective officers thereunto duly authorized as of the day
and year first above written.

                                         NRG NORTHEAST GENERATING LLC

                                         By:  /s/ Craig Mataczynski
                                              -------------------------------
                                              Name: Craig Mataczynski
                                              Title: President

                                         GUARANTORS

                                         ARTHUR KILL POWER LLC

                                         By:  /s/ Brian B. Bird
                                              -------------------------------
                                              Name: Brian B. Bird
                                              Title: Treasurer

                                         ASTORIA GAS TURBINE POWER LLC

                                         By:  /s/ Brian B. Bird
                                              -------------------------------
                                              Name: Brian B. Bird
                                              Title: Treasurer

                                         CONNECTICUT JET POWER LLC

                                         By:  /s/ Brian B. Bird
                                              -------------------------------
                                              Name: Brian B. Bird
                                              Title: Treasurer

                                         DEVON POWER LLC

                                         By:  /s/ Brian B. Bird
                                              -------------------------------
                                              Name: Brian B. Bird
                                              Title: Treasurer

                                         DUNKIRK POWER LLC

                                         By:  /s/ Brian B. Bird
                                              -------------------------------
                                              Name: Brian B. Bird
                                              Title: Treasurer

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<PAGE>   99
                                      -91-

                                         HUNTLEY POWER LLC

                                         By:  /s/ Brian B. Bird
                                              -------------------------------
                                              Name: Brian B. Bird
                                              Title: Treasurer

                                         MIDDLETOWN POWER LLC

                                         By:  /s/ Brian B. Bird
                                              -------------------------------
                                              Name: Brian B. Bird
                                              Title: Treasurer

                                         MONTVILLE POWER LLC

                                         By:  /s/ Brian B. Bird
                                              -------------------------------
                                              Name: Brian B. Bird
                                              Title: Treasurer

                                         NORWALK POWER LLC

                                         By:  /s/ Brian B. Bird
                                              -------------------------------
                                              Name: Brian B. Bird
                                              Title: Treasurer

                                         OSWEGO HARBOR POWER LLC

                                         By:  /s/ Brian B. Bird
                                              -------------------------------
                                              Name: Brian B. Bird
                                              Title: Treasurer

                                         SOMERSET POWER LLC

                                         By:  /s/ Brian B. Bird
                                              -------------------------------
                                              Name: Brian B. Bird
                                              Title: Treasurer

                                         THE CHASE MANHATTAN BANK
                                          as Trustee

                                         By:  /s/ Annette M. Marsula
                                              -------------------------------
                                              Name: Annette M. Marsula
                                              Title: Vice President

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<PAGE>   100
                                      -92-

                                         THE CHASE MANHATTAN BANK
                                           as Securities Intermediary

                                         By:  /s/ Annette M. Marsula
                                              -------------------------------
                                              Name: Annette M. Marsula
                                              Title: Vice President

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<PAGE>   101

                                                                       EXHIBIT A

                          FORM OF ACCEPTABLE GUARANTEE

       This GUARANTEE AGREEMENT (this "Guarantee"), dated as of ___________
between [NRG Energy/Affiliate of NRG Energy/Acceptable Bank], a corporation duly
organized and validly existing under the laws of _____________ (the "Guarantor")
and The Chase Manhattan Bank, as Trustee (the "Trustee") on behalf of the
Secured Parties (as defined in the Collateral Agency and Intercreditor
Agreement).

                                    RECITALS

       1. NRG Northeast Generating LLC (the "Issuer"), Arthur Kill Power LLC,
Astoria Gas Turbines Power LLC, Connecticut Jet Power LLC, Devon Power LLC,
Dunkirk Power LLC, Huntley Power LLC, Middletown Power LLC, Montville Power LLC,
Norwalk Power LLC, Oswego Harbor Power LLC and Somerset Power LLC (each, a
"Subsidiary Guarantor" and collectively, the "Subsidiary Guarantors") have
entered into the Indenture dated as of February 22, 2000 with the Trustee.

       2. In order to fund the Debt Service Reserve Account so that the
obligations of the Issuer under Article 4 of the Indenture shall be released,
and for other good and valuable consideration, the receipt and sufficiency of
which are acknowledged, the Guarantor has agreed to guarantee the payment of the
Guaranteed Obligation (as defined below).

       Accordingly, the Guarantor agrees with the Trustee as follows:

                                    ARTICLE 1
                                   DEFINITIONS

       Unless otherwise defined, all capitalized terms used in this Guarantee
shall have the meanings given in the Indenture. The rules of interpretation set
forth in Article 1 of the Indenture shall apply to this Guarantee.

                                    ARTICLE 2
                                    GUARANTEE

       2.01 The Guarantee. The Guarantor absolutely, unconditionally and
irrevocably guarantees to the Trustee on behalf of the Holders of the Bonds and
their respective successors and assigns the prompt payment of up to US$   (as
such amount may be reduced or increased from time to time, the "Guaranteed
Obligation") upon receipt of a written request from the Issuer therefor.

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<PAGE>   102

                                      -2-

       The Guarantor further agrees that it will promptly pay the amount
specified in such written notice, but in no event more than the Guaranteed
Obligation, on the date of receipt of such written notice. The delivery of such
notice by the Issuer to the Guarantor shall in accordance with Article 4 of the
Indenture constitute sufficient demand on the Guarantor to make the payment
specified in such notice.

       2.02 Obligations Unconditional. The obligations of the Guarantor under
Section 2.01 are absolute, unconditional and irrevocable, irrespective of any
actual or asserted lack of value, genuineness, validity, regularity or
enforceability of the obligations of the Issuer under the Indenture, any other
Transaction Document or any other agreement or instrument referred to therein,
or any substitution, release or exchange of any other guarantee of or security
for the Guaranteed Obligation, and, to the fullest extent permitted by
applicable Law, irrespective of any other circumstance whatsoever that might
otherwise constitute a legal or equitable discharge or defense of a surety or
guarantor, it being the intent of this Article 2 that the obligations of the
Guarantor under this Guarantee shall be absolute and unconditional, under any
and all circumstances.

       Subject to Section 2.01, the Guarantor expressly waives diligence,
presentment, demand of payment, protest and all notices whatsoever, and any
requirement that the Trustee or any Holder exhaust any right, power or remedy or
proceed against the Issuer or the Subsidiary Guarantors under the Indenture or
any other Transaction Document or any other agreement or instrument referred to
therein, or against any other Person under any other guarantee of, or security
for, any of the Guaranteed Obligation.

       2.03 Instrument for the Payment of Money. The Guarantor acknowledges that
this guarantee constitutes an instrument for the payment of money only, and
consents and agrees that the Trustee or any Holder, at its sole option, in the
event of a dispute by such Guarantor in the payment of any moneys due hereunder,
shall have the right to bring motion-action under New York CPLR Section 3213.

       2.04 Reduction of Guaranteed Obligation. The Guaranteed Obligation shall
be reduced automatically in accordance with clause 4.1(d)(i) of the Indenture
and the Trustee shall promptly provide to the Guarantor notice of such
reduction. Contemporaneous with the giving of such notice, the Trustee shall
annotate this Guarantee to reflect the Guaranteed Obligation as so reduced.

                                    ARTICLE 3
                         REPRESENTATIONS AND WARRANTIES

       The Guarantor represents and warrants that:

       3.01 Power and Authority. The Guarantor has the limited liability company
power and authority to (i) execute and deliver this Guarantee and perform its
obligations hereunder, (ii) to conduct its business as currently conducted and
(iii) to own its property.

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                                      -3-

       3.02 Valid Existence. The Guarantor is duly organized and is validly
existing under and pursuant to the laws of the jurisdiction of its organization
and is qualified to do business and is in good standing in all jurisdictions
necessary for it to conduct its business and own its property except where the
failure to so qualify or be in good standing would not have a Material Adverse
Effect.

       3.03 Due Authorization. The execution, delivery and performance by the
Guarantor of this Guarantee have been duly authorized by all necessary corporate
action, and do not and shall not require any further consents or approvals which
have not been obtained, or violate any provision of any Law or breach any
agreement presently in effect with respect to or binding on the Guarantor or its
properties except where such violations or breach would not have a Material
Adverse Effect.

       3.04 Binding Obligation. This Guarantee is a legal, valid and binding
obligation of the Guarantor, enforceable against it in accordance with its
terms, except as such enforceability may be limited in each case by bankruptcy,
insolvency, fraudulent conveyance, reorganization, moratorium or similar laws
affecting the enforceability of creditors' rights generally (and to the possible
judicial application of foreign laws or governmental action affecting the rights
of creditors generally) and except as such enforceability is subject to the
application of general principles of equity (regardless of whether the issue of
enforceability is considered in a proceeding in equity or at law), including
without limitation (i) the possible unavailability of specific performance,
injunctive relief or any other equitable remedy and (ii) concepts of
materiality, reasonableness, good faith and fair dealing.

                                    ARTICLE 4
                                  MISCELLANEOUS

       4.01 Notices. All notices required or permitted under the terms and
provisions of this Guarantee shall be in writing (including by telex or fax) in
the English language delivered to the intended recipient. Any such notice shall
be effective when received if given in accordance with the provisions of Section
1.4 of the Indenture to the address set out beneath such party's signature to
this Guarantee.

       4.02 Severability. If any provision hereof is invalid, illegal or
unenforceable in any jurisdiction, then to the fullest extent permitted by law,
(i) the other provisions hereof shall remain in full force and effect in such
jurisdiction and shall be liberally construed in favor of the Trustee and the
Secured Parties in order to carry out the intentions of the parties hereto as
nearly as may be possible and (ii) the invalidity, illegality or
unenforceability of any provision hereof in any jurisdiction shall not affect
the validity, legality or enforceability of such provision in any other
jurisdiction.

       4.03 Benefit of Guarantee. This Guarantee shall be binding upon and inure
to the benefit of the Guarantor and the Trustee and their respective successors,
transferees and assigns.

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<PAGE>   104

                                      -4-

       4.04 Language. The language of this Guarantee is the English language and
no translation made or to be made hereof shall have any legal validity.

       4.05 Governing Law. This Guarantee shall be governed by, and construed in
accordance with, the laws of the State of New York applicable to agreements made
and to be performed entirely within the State of New York, without regard to
principles of conflicts of law thereof to the extent the application of such
principles would cause the application of the laws of any other jurisdiction.

       4.06 Further Assurances. The Guarantor shall execute and deliver all such
instruments and take all such actions as may be reasonably necessary to
effectuate fully the purposes of this Guarantee.

       4.07 Term. This Guarantee shall terminate upon the earlier to occur of
indefeasible payment in full of the Guaranteed Obligation and reduction of the
Guaranteed Obligation to zero.

       4.08 Amendments. Except as otherwise expressly provided in this
Guarantee, any provision of this Guarantee may be amended or modified only by an
instrument in writing signed by the parties hereto.

       4.09 Submission to Jurisdiction and Venue. Any legal action or proceeding
against the Guarantor with respect to this Guarantee shall be brought and
enforced in the U.S. state or federal courts located in the Borough of
Manhattan, The City of New York, New York, and, by execution and delivery of
this Guarantee, the Guarantor irrevocably accepts for itself and in respect of
its property, generally, irrevocably and unconditionally, the jurisdiction of
the aforesaid courts. A judgment, after exhaustion of all available appeals, in
any such action or proceeding shall be conclusive and binding upon the Guarantor
and may be enforced in any other jurisdiction by a suit upon such judgment, a
certified copy of which shall be conclusive evidence of the judgment.

       4.10 Appointment of Process Agent. The Guarantor irrevocably designates,
appoints and empowers CT Corporation System, with offices on the date of this
Guarantee at 111 8th Avenue, 13th Floor, New York, New York 10011, as its
designee, appointee and agent with respect to any action or proceeding to
receive, accept and acknowledge for and on its behalf, and in respect of its
property, service of any and all legal process, summons, notices and documents
which may be served in any such action or proceeding and agrees that the failure
of any such agent to give any advice of any service of process to it shall not
impair or affect the validity of such service or of any judgment based thereon.
If for any reason such designee, appointee and agent shall cease to be available
to act as such, the Guarantor shall designate a new designee, appointee and
agent in the United States on the terms and for the purposes of this provision
reasonably satisfactory to the Trustee. The Guarantor further irrevocably
consents to the service of process out of any of the aforementioned courts in
any such action or proceeding by the mailing of copies thereof by registered or
certified mail, postage prepaid, to it, at its address set forth below, such
service to become effective 30 days after such mailing. Nothing in this
Guarantee shall affect the right of the Trustee to serve process or to commence
legal proceedings or otherwise proceed against the Guarantor in any other
jurisdiction in any other manner permitted by law. The

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<PAGE>   105

                                      -5-

Guarantor waives irrevocably, to the extent permitted by law, any objection to
the laying of venue in New York, New York, and any claim of inconvenient forum
in respect of any such action in New York, New York to which it might otherwise
be entitled in any actions arising out of or based on this Guarantee.

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   106

                                      -6-

       IN WITNESS WHEREOF, each party has caused this Guarantee to be duly
executed and delivered by its officer thereto duly authorized as of the date
first above written.

[NRG Energy/Affiliate of NRG Energy/Acceptable Bank]
as Guarantor

By:       ....................................
Title:    ....................................

Address:
               --------------------

               --------------------

               --------------------

Attention:
               --------------------
Telephone:
               --------------------
Telecopy:
               --------------------

THE CHASE MANHATTAN BANK,
not in its individual capacity, but solely
as Trustee

By:       ....................................
Title:    ....................................

Address:       The Chase Manhattan Bank
               Capital Markets Fiduciary Services
               450 W. 33rd Street, 15th Floor
               New York, New York 10001

Attention:     Annette Marsula
               International and Project Finance Group
Telephone:     (212) 946-7557
Telecopy:      (212) 946-8177

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   107

                                                                       EXHIBIT B

                            SUBORDINATION PROVISIONS

       Section 1. [NRG Northeast Generating LLC, a limited liability company
organized under the laws of Delaware] (the "Company"), hereby covenants and
agrees, and [NAME OF SUBORDINATED LENDER] (the "Subordinated Lender"), likewise
agrees, that, to the extent and in the manner set forth in this Agreement,
[describe subordinated indebtedness] (the "Subordinated Indebtedness"), and the
payment from whatever source of the principal of, and interest and premium (if
any) on, the Subordinated Indebtedness, are hereby expressly made subordinate
and subject in right of payment to the prior payment in full in cash of all
Senior Indebtedness (as hereinafter defined). All capitalized terms used herein
and not otherwise defined herein shall have the meanings ascribed thereto,
whether directly or by reference to another agreement or document, in the
Indenture dated as of February 22, 2000 (as amended, supplemented or modified
and in effect from time to time, the "Indenture") among the Company, the
Guarantors party thereto and The Chase Manhattan Bank, as trustee (in such
capacity, together with its successors and assigns, the "Trustee") for the
Holders.

       For purposes hereof, "Senior Indebtedness" shall mean all indebtedness,
liabilities and other obligations of the Company (including, but not limited to,
all such obligations in respect of principal, premiums, interest, fees,
reimbursement obligations, penalties, indemnities, legal expenses, costs and
other expenses, whether due after acceleration or otherwise) to the Secured
Parties (as defined in the Collateral Agency and Intercreditor Agreement) (of
whatsoever nature and howsoever evidenced) under or pursuant to the Collateral
Documents and the other Financing Documents, in each case, direct or indirect,
primary or secondary, fixed or contingent, now or hereafter arising out of or
relating to any such agreement or document. The term "Senior Indebtedness" shall
include any interest accruing after the date of any filing by the Company of any
petition in bankruptcy or the commencing of any bankruptcy, insolvency or
similar proceedings with respect to the Company, whether or not such interest is
allowable as a claim in any such proceeding.

       Section 2. The Subordinated Lender further agrees that:

       (a) (i) Unless and until the Senior Indebtedness shall have been paid or
   otherwise satisfied in full, the Subordinated Lender shall not ask, demand,
   sue for, take or receive from the Company, directly or indirectly, in cash or
   other property or by set-off or in any other manner (including, without
   limitation, from or by way of the Collateral or any guaranty of payment or
   performance), payment of all or any of the Subordinated Indebtedness, except
   as permitted under the Indenture and shall be paid solely from cash that may
   be applied to Restricted Payments under Section 6.15 of the Indenture. For
   the purposes of these provisions, the Senior Indebtedness shall not be deemed
   to have been paid or satisfied in full until the Senior Indebtedness shall
   have been indefeasibly so paid in cash to the Secured Parties (after the
   passage of any relevant preference periods).

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<PAGE>   108

                                      -2-

       (ii) Upon any distribution of all or any of the assets of the Company to
   creditors of the Company upon the dissolution, winding up, liquidation,
   arrangement, reorganization or composition of the Company, whether in any
   bankruptcy, insolvency, arrangement, reorganization, receivership or similar
   proceedings or upon an assignment for the benefit of creditors or any other
   marshalling of the assets and liabilities of the Company or otherwise, any
   payment or distribution of any kind (whether in cash, property or securities)
   which otherwise would be payable or deliverable upon or with respect to the
   Subordinated Indebtedness but for the provisions of this Agreement,
   including, without limitation, any such payment or distribution that may be
   payable or deliverable by reason of the payment of any other indebtedness of
   the Company being subordinated to the payment of the Subordinated
   Indebtedness shall be paid or delivered directly to the Collateral Agent for
   application (in the case of cash) to or as Collateral (in the case of
   non-cash property or securities) for the payment or prepayment of the Senior
   Indebtedness until the Senior Indebtedness has been paid or otherwise
   satisfied in full in cash.

       (iii) Each of the Secured Parties may demand specific performance of
   these terms of subordination, whether or not the Company shall have complied
   with any of the provisions hereof applicable to them at any time when the
   Subordinated Lender shall have failed to comply with any of such provisions
   applicable to it. The Subordinated Lender hereby irrevocably waives any
   defense based on the adequacy of a remedy at law, which might be asserted as
   a bar to such remedy of specific performance.

       (iv) So long as any of the Senior Indebtedness shall remain unpaid or
   otherwise unsatisfied, the Subordinated Lender shall not commence or join
   with any creditor other than the Collateral Agent in commencing any
   proceeding referred to in subsection (ii) above for the payment of any
   amounts which otherwise would be payable or deliverable upon or with respect
   to the Subordinated Indebtedness.

       (v) Subject to the indefeasible payment or satisfaction in full in cash
   of all of the Senior Indebtedness, the Subordinated Lender shall be
   subrogated to the rights of the Secured Parties to receive payments or
   distributions of assets of the Company made on the Senior Indebtedness until
   the Subordinated Indebtedness has been satisfied in full.

       (vi) In the event that, notwithstanding the foregoing provisions of this
   Section 2, the Subordinated Lender shall have received, before all Senior
   Indebtedness is paid in full in cash or payment thereof is otherwise provided
   for, any such payment or distribution of assets of the Company of any kind or
   character, whether in cash, property or securities, including any such
   payment or distribution arising out of the exercise by the Subordinated
   Lender of a right of set-off or counterclaim and any such payment or
   distribution received by reason of any other indebtedness of the Company
   being subordinated to the Subordinated Indebtedness, then, and in such event,
   such payment or distribution shall be held in trust for the benefit of the
   Secured Parties, and shall be immediately paid over to the Collateral Agent,
   to the extent necessary to make payment in full in cash of all Senior
   Indebtedness remaining unpaid, after giving effect to any concurrent payment
   or distribution to the Secured Parties.

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   109

                                      -3-

       The foregoing provisions regarding subordination are for the benefit of
the Secured Parties and shall be enforceable by them directly against the
Subordinated Lender, and no Secured Party shall be prejudiced in its right to
enforce subordination of any of the Subordinated Indebtedness by any act or
failure to act by the Company or anyone in custody of its assets or property.
Notwithstanding anything to the contrary contained in the foregoing provisions,
the Subordinated Lender may receive and retain payments in respect of the
Subordinated Indebtedness from the Company to the extent that such payments are
permitted by the Indenture.

       (b) So long as any Senior Indebtedness remains outstanding, the following
provisions shall apply:

       (i) If an Event of Default shall have occurred and be continuing, the
   Collateral Agent, on behalf of the Secured Parties, shall be permitted to
   take any and all actions to exercise any and all rights, remedies and options
   which it may have under the Collateral Agency and Intercreditor Agreement and
   the other Security Documents.

       (ii) The Subordinated Lender shall not, without the prior written consent
   of the Secured Parties, (A) exercise any rights or enforce any remedies or
   assert any claim with respect to the Collateral, (B) seek to foreclose any
   Lien or sell the Collateral, or (C) take any action, directly or indirectly,
   or institute any proceedings, directly or indirectly, with respect to any of
   the foregoing.

       (iii) The Subordinated Lender hereby waives: (A) notice of the existence,
   creation or non-payment of all or any of the Senior Indebtedness and (B) to
   the fullest extent permitted by law, any right it may have to require the
   Collateral Agent to marshal assets.

       (c) The Secured Parties may, at any time and from time to time, without
any consent of or notice to the Subordinated Lender and without impairing or
releasing the obligations of the Subordinated Lender: (A) amend, modify, extend,
renew, waive or consent to in any manner, any provision of any agreement under
which any of the Senior Indebtedness is outstanding in accordance with the terms
thereof; (B) sell, exchange, release, not perfect and otherwise deal with any
property at any time pledged, assigned or mortgaged to secure the Senior
Indebtedness in accordance with the Security Documents; (C) release anyone
liable in any manner under or in respect of the Senior Indebtedness; (D)
exercise or refrain from exercising any rights against the Company and others;
and (E) apply any sums from time to time received to payment or satisfaction of
the Senior Indebtedness.

       (d) After the payment in full of all amounts due in respect of the Senior
Indebtedness, the holder or holders of the Subordinated Indebtedness shall be
subrogated to the rights of the holders of the Senior Indebtedness to receive
payments or distributions of cash, property or securities of the Company
applicable to the Senior Indebtedness until the principal of, premium, if any,
interest on and all other amounts due or to become due with respect to the
Subordinated Indebtedness shall be paid in full; and, for the purposes of such
subrogation, no payments or distributions to the holders of the Senior
Indebtedness of any cash, property or securities to which the holder or holders
of the Subordinated Indebtedness would be entitled but

                       NRG Northeast Generating Indenture
                       ----------------------------------

<PAGE>   110

                                      -4-

for the provisions hereof, and no payment pursuant to these provisions to the
holders of the Senior Indebtedness by any holder of the Subordinated
Indebtedness shall, as among the Company, its creditors other than holders of
the Senior Indebtedness and the holder or holders of the Subordinated
Indebtedness, be deemed to be a payment by the Company to or on account of the
Senior Indebtedness. No payment or distributions to the holders of the Senior
Indebtedness which such holder or holders of the Subordinated Indebtedness shall
be entitled to receive pursuant to such subrogation shall, as among the Company,
its creditors other than holders of the Senior Indebtedness and the holder or
holders of the Subordinated Indebtedness be deemed to be a payment by the
Company or on account of the Subordinated Indebtedness.

       Nothing contained in this instrument is intended to or shall impair as
among the Company, its creditors other than the holders of the Senior
Indebtedness, and the holders of the Subordinated Indebtedness, the obligation
of the Company, which is absolute and unconditional, to pay to the holders of
the Subordinated Indebtedness as and when the same shall become due and payable
in accordance with its terms, or to affect the relative rights of the holders of
the Subordinated Indebtedness and creditors of the Company other than the
holders of the Senior Indebtedness.

       Section 3. The Subordinated Lender agrees not to take any action in
respect of or to enforce any right of subrogation arising as a result of the
Subordinated Lender paying over amounts to the holders of the Senior
Indebtedness as provided herein, prior to payment in full in cash of the Senior
Indebtedness.

       Section 4. The Subordinated Lender agrees that, if it shall fail to file
claims or proofs of claim with respect to the Subordinated Indebtedness at least
30 days prior to the expiration of the period in which such claims or proofs of
claim shall be required to be filed, the holders of the Senior Indebtedness are
authorized to file such claims or proofs of claim on behalf of the Subordinated
Lender as its attorney-in-fact.

                       NRG Northeast Generating Indenture
                       ----------------------------------<PAGE>   1
                                                                     EXHIBIT 4.2

                                                                  EXECUTION COPY

================================================================================

                          FIRST SUPPLEMENTAL INDENTURE

                          dated as of February 22, 2000

                                       to

                                    INDENTURE

                          dated as of February 22, 2000

                                      among

                          NRG NORTHEAST GENERATING LLC

                           the GUARANTORS party hereto

                                       and

                      THE CHASE MANHATTAN BANK, as Trustee

================================================================================

<PAGE>   2

                  FIRST SUPPLEMENTAL INDENTURE, dated as of February 22, 2000
(this "First Supplemental Indenture"), among NRG NORTHEAST GENERATING LLC, a
Delaware limited liability company (together with its successors and assigns,
the "Company"), its executive office and mailing address being at 1221 Nicollet
Mall, Suite 700, Minneapolis, Minnesota 55403, the GUARANTORS party hereto and
THE CHASE MANHATTAN BANK, a New York banking corporation (the "Trustee"), its
corporate trust office and mailing address being at 450 W. 33rd Street, 15th
Floor, New York, NY 10001 to the Indenture dated as of February 22, 2000 (the
"Original Indenture") among the Company, the Guarantors and the Trustee.

                  WHEREAS, the Company, the Guarantors and the Trustee have
heretofore executed and delivered the Original Indenture to provide for the
issuance from time to time of bonds, debentures, notes or other evidences of
indebtedness to be issued in one or more series;

                  WHEREAS, Sections 2.1, 2.3 and 14.1 of the Original Indenture
provide, among other things, that the Company and the Trustee may enter into
indentures supplemental to the Original Indenture for, among other things, the
purpose of establishing the designation, form, terms and provisions of Bonds of
any series as permitted by Sections 2.1, 2.3 and 14.1 of the Original Indenture;

                  WHEREAS, the Company (i) desires the issuance of three
separate series of Bonds to be designated as hereinafter provided and (ii) has
requested the Trustee to enter into this First Supplemental Indenture for the
purpose of establishing the designation, form, terms and provisions of the Bonds
of each such series;

                  WHEREAS, all action on the part of the Company necessary to
authorize the issuance of the Bonds under the Original Indenture and this First
Supplemental Indenture (the Original Indenture, as supplemented by this First
Supplemental Indenture, being hereinafter called the "Indenture") has been duly
taken; and

                  WHEREAS, all acts and things necessary to make the Bonds, when
executed by the Company and authenticated and delivered by the Trustee as
provided in the Original Indenture, the legal, valid and binding obligations of
the Company, and to constitute these presents a valid and binding supplemental
indenture according to its terms, have been done and performed, and the
execution of this First Supplemental Indenture and the creation and issuance
under the Indenture of said Bonds have in all respects been duly authorized, and
the Company, in the exercise of the legal right and power vested in it, executes
this First Supplemental Indenture and proposes to create, execute, issue and
deliver the Bonds.

                  NOW, THEREFORE, THIS FIRST SUPPLEMENTAL INDENTURE WITNESSETH:

                  That, in order to establish the designation, form, terms and
provisions of, and to authorize the authentication and delivery of, said Bonds,
and in consideration of the acceptance of the Bonds by the Holders thereof and
of other good and valuable consideration, the receipt and sufficiency of which
are hereby acknowledged, the parties hereto hereby agree as follows:

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   3

                                      -2-

                                   ARTICLE I

                                   DEFINITIONS

                  (a) Capitalized terms used herein and not otherwise defined
herein shall have the respective meanings ascribed thereto in the Original
Indenture.

                  (b) For all purposes of this First Supplemental Indenture,
except as otherwise expressly provided or unless the context otherwise requires,
the following terms shall have the following respective meanings (such meanings
shall apply equally to both the singular and plural forms of the respective
terms):

                  "Closing Date" means February 22, 2000, the date on which the
Initial Bonds are first issued and sold under the Indenture.

                  "Exchange Bonds" shall mean, collectively, the Series A-1
Senior Secured Bonds Due 2004, the Series B-1 Senior Secured Bonds Due 2010 and
the Series C-1 Senior Secured Bonds Due 2024 to be issued under the Indenture in
exchange for the Initial Bonds pursuant to the Exchange Offer.

                  "Exchange Offer" shall mean the offer by the Company, pursuant
to an effective registration statement filed with the SEC, to exchange all of
the Exchange Bonds for all of the outstanding Initial Bonds in accordance with
the terms and provisions of the Registration Rights Agreement.

                  "Exchange Offer Consummation Date" shall mean the date on
which the Exchange Offer is consummated in accordance with the terms and
provisions of the Registration Rights Agreement.

                  "Guarantor" means each of the Initial Guarantors and any
Subsequent Guarantor.

                  "Initial Bonds" means, collectively, the Series A Senior
Secured Bonds Due 2004, the Series B Senior Secured Bonds Due 2015 and the
Series C Senior Secured Bonds Due 2024, being issued by the Company under the
Indenture and sold to the Initial Purchasers pursuant to the Purchase Agreement
dated February 15, 2000 among the Company, Arthur Kill Power LLC, a Delaware
limited liability company, Astoria Gas Turbine Power LLC, a Delaware limited
liability company, Connecticut Jet Power LLC, a Delaware limited liability
company, Devon Power LLC, a Delaware limited liability company, Dunkirk Power
LLC, a Delaware limited liability company, Huntley Power LLC, a Delaware limited
liability company, Middletown Power LLC, a Delaware limited liability company,
Montville Power LLC, a Delaware limited liability company, Norwalk Power LLC, a
Delaware limited liability company, Oswego Harbor Power LLC, a Delaware limited
liability company, Somerset Power LLC, a Delaware limited liability company and
the Initial Purchasers.

                  "Initial Guarantors" means each of Arthur Kill Power LLC,
Astoria Power LLC, Connecticut Jet Power LLC, Devon Power LLC, Dunkirk Power
LLC, Huntley Power LLC,

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   4

                                      -3-

Middletown Power LLC, Montville Power LLC, Norwalk Harbor Power LLC, Oswego
Harbor Power LLC and Somerset Power LLC.

                  "Institutional Accredited Investor" shall have the meaning
ascribed thereto in Section 2.1(b) hereof.

                  "Make-Whole Premium" means an amount equal to the excess, if
any, of (i) the present value of all interest and principal payments scheduled
to become due after the date of the optional redemption by the Issuer in respect
of the Bonds being redeemed (such present value to be determined on the basis of
a discount rate equal to the sum of (a) the Treasury Rate and (b) 25 basis
points) over (ii) the Outstanding principal amount of the applicable Bonds.

                  "QIB" shall have the meaning given to such term in Section
2.1(b) hereof.

                  "Regular Record Date", for any Bond of a series for the
Scheduled Payment Date of any installment of principal thereof or payment of
interest thereon, means the 16th day (whether or not a Business Day) next
preceding such Scheduled Payment Date, or any other date specified for such
purpose in the form of Bond of such series attached to the Series Supplemental
Indenture relating to the Bonds of such series.

                  "Regulation S Global Bond" means one or more Bonds deposited
with a custodian for, and registered in the name of a nominee of, the DTC,
interest in which will be held for the benefit of purchasers of the Bonds in
offshore transactions under Regulation S.

                  "Resale Restriction Termination Date" means the period of two
years after the later of the original issue date of a Restricted Security and
the last date on which the Issuer or any affiliate of the Issuer was the owner
of such Restricted Security (or any predecessor of such Restricted Security).

                  "Restricted Securities" shall have the meaning given to such
term in Section 2.8 hereof.

                  "Rule 144A" means Rule 144A promulgated under the Securities
Act.

                  "Rule 144A Global Bond" means the one or more Bonds deposited
with a custodian for, and registered in the name of a nominee of, the DTC,
interests in which will be held for the benefit of U.S. purchasers of bonds who
are QIBs under Rule 144A.

                  "Series A Senior Secured Bonds Due 2004" shall have the
meaning given to such term in Section 2.1(a) hereof.

                  "Series B Senior Secured Bonds Due 2015" shall have the
meaning given to such term in Section 2.2(a) hereof.

                  "Series C Senior Secured Bonds Due 2024" shall have the
meaning given to such term in Section 2.3(a) hereof.

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   5

                                      -4-

                  "Series A-1 Senior Secured Bonds Due 2004" shall have the
meaning given to such term in Section 2.1(a) hereof.

                  "Series B-1 Senior Secured Bonds Due 2015" shall have the
meaning given to such term in Section 2.2(a) hereof.

                  "Series C-1 Senior Secured Bonds Due 2024" shall have the
meaning given to such term in Section 2.3(a) hereof.

                  "Subsequent Guarantor" means any Subsidiary of the Issuer,
other than an Initial Guarantor, that the Issuer designates as a Guarantor
subsequent to the Closing Date.

                  "Treasury Rate" means the yield to maturity at the time of
computation of United States Treasury securities with a final maturity (as
compiled and published in the most recent Federal Reserve Statistical Release H.
15(519) which has become publicly available at least two Business Days in New
York prior to the Redemption Date (or, if such statistical release is no longer
published, any publicly available source or similar market data)) most nearly
equal to the remaining average life on the Redemption Date of the Bonds being
redeemed, provided, however, that if the period from the Redemption Date to the
maturity date of the series of Bonds being redeemed is less than one year, the
weekly average yield on actually traded United States Treasury securities
adjusted to a constant maturity of one year shall be used.

                                   ARTICLE II

                             THE TERMS OF THE BONDS

                  SECTION 2.1.  Terms of 8.065% Series A Senior Secured Bonds
Due 2004 and 8.065% Series A-1 Senior Secured Bonds Due 2004.

                  (a) There are hereby created two series of Bonds designated:
(i) 8.065% Series A Senior Secured Bonds Due 2004, in the aggregate principal
amount which at any time may not exceed $320,000,000 (the "Series A Senior
Secured Bonds Due 2004"), and (ii) 8.065% Series A-1 Senior Secured Bonds Due
2004, in an aggregate principal amount which at any time may not exceed
$320,000,000 less the aggregate principal amount of Series A Senior Secured
Bonds Due 2004 then Outstanding (the "Series A-1 Senior Secured Bonds Due
2004"). The Series A Senior Secured Bonds Due 2004 may forthwith be executed by
the Company and delivered to the Trustee for authentication and delivery by the
Trustee in accordance with the provisions of Section 2.4 of the Original
Indenture. On or prior to the Exchange Offer Consummation Date for the Series A
Senior Secured Bonds Due 2004, the Company may execute and deliver to the
Trustee, and upon delivery of an Issuer Order to the Trustee in accordance with
the provisions of Section 2.4 of the Original Indenture, the Trustee shall
authenticate and deliver, the Series A-1 Senior Secured Bonds Due 2004 in
exchange for Series A Senior Secured Bonds Due 2004 validly surrendered to the
Trustee pursuant to the Exchange Offer. Such Issuer Order shall specify the
amount of the Series A-1 Senior Secured Bonds Due 2004 to be authenticated and
the date on which such Series A-1 Senior Secured

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   6

                                      -5-

Bonds Due 2004 are to be authenticated. The aggregate principal amount of the
Series A Senior Secured Bonds Due 2004 together with the Series A-1 Senior
Secured Bonds Due 2004 Outstanding at any time may not exceed $320,000,000,
except as provided in the Original Indenture.

                  (b) The Series A Senior Secured Bonds Due 2004, (i) if issued
to Persons that are institutional "accredited investors" meeting the
requirements of Rule 501(a)(1), (2), (3) or (7) under the Securities Act (each,
an "Institutional Accredited Investor") that are not QIBs (as defined below),
shall be issued in definitive form, substantially in the form of Schedule 1-A
hereto, registered in the name of the purchaser thereof and (ii) (A) if issued
to "qualified institutional buyers" (as defined in Rule 144A under the
Securities Act; each, a "QIB") in reliance on Rule 144A under the Securities
Act, or (B) if issued in offshore transactions to Non-U.S. Persons in reliance
on Regulation S shall be issued in the form of one or more Global Bonds
substantially in the form of Schedule 1-B hereto, shall be deposited on behalf
of the purchasers of the Initial Bonds represented thereby with the Trustee (at
its respective address for notices set forth in Section 1.4 of the Original
Indenture), as custodian for the Registered Depositary, shall be registered in
the name of the Registered Depositary or a nominee of the Registered Depositary
and the aggregate principal amount of Series A Senior Secured Bonds Due 2004 so
issued may from time to time be increased or decreased by adjustments made on
the records of the Trustee and the Registered Depositary or its nominee.

                  (c) Each of the Series A Senior Secured Bonds Due 2004 and
the Series A-1 Senior Secured Bonds Due 2004 shall have and be subject to such
other terms as provided in the Indenture.

                  (d) The forms of the Series A-1 Senior Secured Bonds Due 2004
shall be substantially identical to the forms of the Series A Senior Secured
Bonds Due 2004, except that: (i) the title of the Series A-1 Senior Secured
Bonds Due 2004 shall be "8.065% Series A-1 Senior Secured Bonds Due 2004"; (ii)
the two paragraphs of the legend appearing immediately beneath the title of such
forms of the Series A Senior Secured Bonds Due 2004 shall be omitted; (iii) the
first sentence of the first paragraph of all such forms shall read in its
entirety as follows:

       "NRG NORTHEAST GENERATING LLC, a Delaware limited liability company
       (hereinafter called the "Company", which term includes any successor or
       assign under the Indenture referred to below), for value received hereby
       promises to pay to [________________], or its registered assigns, the
       outstanding Principal Amount hereof [-- if the Bond is in the form of a
       global security insert, "after subtracting the aggregate principal amount
       of any definitive Bonds issued in exchange for a portion or portions
       hereof"], such payment to be made in semiannual installments on June 15
       and December 15 of each year (commencing December 15, 2000) and ending on
       the final Scheduled Payment Date set forth above, each such installment
       to be in the amount and payable on the date set forth on Annex A attached
       hereto (provided that the portion of the Principal Amount remaining
       unpaid on the final Scheduled Payment Date, together with all interest
       accrued thereon, shall in any and all cases be due and payable on the
       final Scheduled Payment Date), and to pay interest on the unpaid portion
       of the Principal

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   7

                                      -6-

       Amount at the interest rate set forth above from the most recent
       Scheduled Payment Date to which interest has been paid or duly provided
       for or, if no interest has been paid or duly provided for, from the date
       of the last interest payment made on the Series A Senior Secured Bonds
       Due 2004 (as defined in the First Supplemental Indenture) occurring prior
       to the issue date set forth above or, if no interest has been paid or
       duly provided for on the Series A Senior Secured Bonds Due 2004, from
       February 22, 2000 semiannually on June 15 and December 15 in each year
       commencing June 15, 2000 (provided, if the issue date is on or after a
       Regular Record Date and prior to the related Scheduled Payment Date, the
       Company shall pay interest from the Scheduled Payment Date immediately
       succeeding the issue date semiannually on June 15 and December 15 in each
       year commencing June 15, 2000) until the Principal Amount is paid in full
       or payment thereof is duly provided for.";

(iv) the thirteenth and fourteenth paragraphs of the reverse of the forms of the
Series A Senior Secured Bonds Due 2004 shall be omitted; and (v) the first
sentence of the first paragraph of the reverse of all such forms shall read in
its entirety as follows: "This bond is one of an authorized issue of Bonds of
the Company known as its 8.065% Series A-1 Senior Secured Bonds Due 2004 (the
"Bonds")."

                  SECTION 2.2. Terms of 8.842% Series B Senior Secured Bonds Due
2015 and 8.842% Series B-1 Senior Secured Bonds Due 2015.

                  (a) There are hereby created two series of Bonds designated:
(i) 8.842% Series B Senior Secured Bonds Due 2015, in the aggregate principal
amount which at any time may not exceed $130,000,000 (the "Series B Senior
Secured Bonds Due 2015"), and (ii) 8.842% Series B-1 Senior Secured Bonds Due
2010, in an aggregate principal amount which at any time may not exceed
$130,000,000 less the aggregate principal amount of Series B Senior Secured
Bonds Due 2015 then Outstanding (the "Series B-1 Senior Secured Bonds Due
2015"). The Series B Senior Secured Bonds Due 2015 may forthwith be executed by
the Company and delivered to the Trustee for authentication and delivery by the
Trustee in accordance with the provisions of Section 2.4 of the Original
Indenture. On or prior to the Exchange Offer Consummation Date for the Series B
Senior Secured Bonds Due 2015, the Company may execute and deliver to the
Trustee, and upon delivery of an Issuer Order to the Trustee in accordance with
the provisions of Section 2.4 of the Original Indenture, the Trustee shall
authenticate and deliver, the Series B-1 Senior Secured Bonds Due 2015 in
exchange for Series B Senior Secured Bonds Due 2015 validly surrendered to the
Trustee pursuant to the Exchange Offer. Such Issuer Order shall specify the
amount of the Series B-1 Senior Secured Bonds Due 2015 to be authenticated and
the date on which such Series B-1 Senior Secured Bonds Due 2015 are to be
authenticated. The aggregate principal amount of the Series B Senior Secured
Bonds Due 2015 together with the Series B-1 Senior Secured Bonds Due 2015
Outstanding at any time may not exceed $130,000,000, except as provided in the
Original Indenture.

                  (b) The Series B Senior Secured Bonds Due 2015, (i) if issued
to Institutional Accredited Investors that are not QIBs, shall be issued in
definitive form, substantially in the form of Schedule 2-A hereto, registered in
the name of the purchaser thereof and (ii) (A) if

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   8

                                      -7-

issued to (A) QIBs in reliance on Rule 144A under the Securities Act, or (B) if
issued in offshore transactions to Non-U.S. Persons in reliance on Regulation S
shall be issued in the form of one or more Global Bonds substantially in the
form of Schedule 2-B hereto, shall be deposited on behalf of the purchasers of
the Initial Bonds represented thereby with the Trustee (at its respective
address for notices set forth in Section 1.4 of the Original Indenture), as
custodian for the Registered Depositary, shall be registered in the name of the
Registered Depositary or a nominee of the Registered Depositary and the
aggregate principal amount of Series B Senior Secured Bonds Due 2015 so issued
may from time to time be increased or decreased by adjustments made on the
records of the Trustee and the Registered Depositary or its nominee.

                  (c) Each of the Series B Senior Secured Bonds Due 2015 and the
Series B-1 Senior Secured Bonds shall have and be subject to such other terms as
provided in the Indenture.

                  (d) The forms of the Series B-1 Senior Secured Bonds Due 2015
shall be substantially identical to the forms of the Series B Senior Secured
Bonds Due 2015, except that: (i) the title of the Series B-1 Senior Secured
Bonds Due 2015 shall be "8.842% Series B-1 Senior Secured Bonds Due 2015"; (ii)
the two paragraphs of the legend appearing immediately beneath the title of such
forms of the Series B Senior Secured Bonds Due 2015 shall be omitted; (iii) the
first sentence of the first paragraph of all such forms shall read in its
entirety as follows:

       "NRG NORTHEAST GENERATING LLC, a Delaware limited liability company
       (hereinafter called the "Company", which term includes any successor or
       assign under the Indenture referred to below), for value received hereby
       promises to pay to [________________], or its registered assigns, the
       outstanding Principal Amount hereof [-- if the Bond is in the form of a
       global security insert, "after subtracting the aggregate principal amount
       of any definitive Bonds issued in exchange for a portion or portions
       hereof"], such payment to be made in semiannual installments on June 15
       and December 15 of each year (commencing June 15, 2007) and ending on the
       final Scheduled Payment Date set forth above, each such installment to be
       in the amount and payable on the date set forth on Annex A attached
       hereto (provided that the portion of the w remaining unpaid on the final
       Scheduled Payment Date, together with all interest accrued thereon, shall
       in any and all cases be due and payable on the final Scheduled Payment
       Date), and to pay interest on the unpaid portion of the Principal Amount
       at the interest rate set forth above from the most recent Scheduled
       Payment Date to which interest has been paid or duly provided for or, if
       no interest has been paid or duly provided for, from the date of the last
       interest payment made on the Series B Senior Secured Bonds Due 2015 (as
       defined in the First Supplemental Indenture) occurring prior to the issue
       date set forth above or, if no interest has been paid or duly provided
       for on the Series B Senior Secured Bonds Due 2015, from February 22, 2000
       semiannually on June 15 and December 15 in each year commencing June 15,
       2000 (provided, if the issue date is on or after a Regular Record Date
       and prior to the related Scheduled Payment Date, the Company shall pay
       interest from the Scheduled Payment Date immediately succeeding the issue
       date semiannually on June 15 and December 15 in each year commencing June
       15, 2000) until the Principal Amount is paid in full or payment thereof
       is duly provided for.";

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   9

                                      -8-

(iv) the thirteenth and fourteenth paragraphs of the reverse of the forms of the
Series B Senior Secured Bonds Due 2015 shall be omitted; and (v) the first
sentence of the first paragraph of the reverse of all such forms shall read in
its entirety as follows: "This bond is one of an authorized issue of Bonds of
the Company known as its 8.842% Series B-1 Senior Secured Bonds Due 2015 (the
"Bonds")."

                  SECTION 2.3. Terms of 9.292% Series C Senior Secured Bonds
Due 2024 and 9.292% Series C-1 Senior Secured Bonds Due 2024.

                  (a) There are hereby created two series of Bonds designated:
(i) 9.292% Series C Senior Secured Bonds Due 2024, in the aggregate principal
amount which at any time may not exceed $300,000,000 (the "Series C Senior
Secured Bonds Due 2024"), and (ii) 9.292% Series C-1 Senior Secured Bonds Due
2024, in an aggregate principal amount which at any time may not exceed
$300,000,000 less the aggregate principal amount of Series C Senior Secured
Bonds Due 2024 then Outstanding (the "Series C-1 Senior Secured Bonds Due
2024"). The Series C Senior Secured Bonds Due 2024 may forthwith be executed by
the Company and delivered to the Trustee for authentication and delivery by the
Trustee in accordance with the provisions of Section 2.4 of the Original
Indenture. On or prior to the Exchange Offer Consummation Date for the Series C
Senior Secured Bonds Due 2024, the Company may execute and deliver to the
Trustee, and upon delivery of an Issuer Order to the Trustee in accordance with
the provisions of Section 2.4 of the Original Indenture, the Trustee shall
authenticate and deliver, the Series C-1 Senior Secured Bonds Due 2024 in
exchange for Series C Senior Secured Bonds Due 2024 validly surrendered to the
Trustee pursuant to the Exchange Offer. Such Issuer Order shall specify the
amount of the Series C-1 Senior Secured Bonds Due 2024 to be authenticated and
the date on which such Series C-1 Senior Secured Bonds Due 2024 are to be
authenticated. The aggregate principal amount of the Series C Senior Secured
Bonds Due 2024 together with the Series C-1 Senior Secured Bonds Due 2024
Outstanding at any time may not exceed $300,000,000, except as provided in the
Original Indenture.

                  (b) The Series C Senior Secured Bonds Due 2024, (i) if issued
to Institutional Accredited Investors that are not QIBs, shall be issued in
definitive form, substantially in the form of Schedule 3-A hereto, registered in
the name of the purchaser thereof and (ii) (A) if issued to QIBs in reliance on
Rule 144A under the Securities Act, (B) if issued in offshore transactions to
Non-U.S. Persons in reliance on Regulation S shall be issued in the form of one
or more Global Bonds substantially in the form of Schedule 3-B hereto, shall be
deposited on behalf of the purchasers of the Initial Bonds represented thereby
with the Trustee (at its respective address for notices set forth in Section 1.4
of the Original Indenture), as custodian for the Registered Depositary, shall be
registered in the name of the Registered Depositary or a nominee of the
Registered Depositary and the aggregate principal amount of Series C Senior
Secured Bonds Due 2024 so issued may from time to time be increased or decreased
by adjustments made on the records of the Trustee and the Registered Depositary
or its nominee.

                  (c) Each of the Series C Senior Secured Bonds Due 2024 and
the Series C-1 Senior Secured Bonds shall have and be subject to such other
terms as provided in the Indenture.

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   10

                                      -9-

                  (d) The forms of the Series C-1 Senior Secured Bonds Due 2024
shall be substantially identical to the forms of the Series C Senior Secured
Bonds Due 2024, except that: (i) the title of the Series C-1 Senior Secured
Bonds Due 2024 shall be "9.292% Series C-1 Senior Secured Bonds Due 2024"; (ii)
the two paragraphs of the legend appearing immediately beneath the title of such
forms of the Series C Senior Secured Bonds Due 2024 shall be omitted; (iii) the
first sentence of the first paragraph of all such forms shall read in its
entirety as follows:

       "NRG NORTHEAST GENERATING LLC, a Delaware limited liability company
       (hereinafter called the "Company", which term includes any successor or
       assign under the Indenture referred to below), for value received hereby
       promises to pay to [________________], or its registered assigns, the
       outstanding Principal Amount hereof [-- if the Bond is in the form of a
       global security insert, "after subtracting the aggregate principal amount
       of any definitive Bonds issued in exchange for a portion or portions
       hereof"], such payment to be made in semiannual installments on June 15
       and December 15 of each year (commencing December 15, 2015) and ending on
       the final Scheduled Payment Date set forth above, each such installment
       to be in the amount and payable on the date set forth opposite on Annex A
       attached hereto (provided that the portion of the Principal Amount
       remaining unpaid on the final Scheduled Payment Date, together with all
       interest accrued thereon, shall in any and all cases be due and payable
       on the final Scheduled Payment Date), and to pay interest on the unpaid
       portion of the Principal Amount at the interest rate set forth above from
       the most recent Scheduled Payment Date to which interest has been paid or
       duly provided for or, if no interest has been paid or duly provided for,
       from the date of the last interest payment made on the Series C Senior
       Secured Bonds Due 2024 (as defined in the First Supplemental Indenture)
       occurring prior to the issue date set forth above or, if no interest has
       been paid or duly provided for on the Series C Senior Secured Bonds Due
       2024, from February 22, 2000 semiannually on June 15 and December 15 in
       each year commencing June 15, 2000 (provided, if the issue date is on or
       after a Regular Record Date and prior to the related Scheduled Payment
       Date, the Company shall pay interest from the Scheduled Payment Date
       immediately succeeding the issue date semiannually on June 15 and
       December 15 in each year commencing June 15, 2000) until the Principal
       Amount is paid in full or payment thereof is duly provided for.";

(iv) the thirteenth and fourteenth paragraphs of the reverse of the forms of the
Series C Senior Secured Bonds Due 2024 shall be omitted; and (v) the first
sentence of the first paragraph of the reverse of all such forms shall read in
its entirety as follows: "This bond is one of an authorized issue of Bonds of
the Company known as its 9.292% Series C-1 Senior Secured Bonds Due 2024 (the
"Bonds")."

                  SECTION 2.4. Denominations.

                  Each Bond of a series created hereby shall be issued in fully
registered form without coupons in minimum denominations of $100,000 and
integral multiples of $1,000 in excess thereof.

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   11

                                      -10-

                  SECTION 2.5. Interest and Principal.

                  Each Bond of a series created hereby shall bear interest on
the unpaid principal amount thereof from time to time outstanding from the date
thereof until such amount is paid in full at the rate of interest set forth in
the forms of such series attached hereto. The principal amount of each Bond of a
series created hereby shall be due and payable in installments as set forth in
the form of Bond of such series attached hereto.

                  Payment of principal of and interest on each Bond of a series
created hereby shall be made (a) if the Company so elects, by check mailed to
the Holder at his or her registered address or (b) otherwise as provided in
Section 2.10 of the Original Indenture; provided that the final installment of
principal payable with respect to each Bond of a series created hereby shall be
payable as provided in Section 8.5 of the Original Indenture (in the case of any
such Bond redeemed) or payable upon presentation and surrender of each such Bond
at the Place of Payment.

                  SECTION 2.6. Redemption; Repurchase.

                  (a) Optional Redemption. Subject to the provisions of Section
8.1 of the Original Indenture, the Bonds of each series created hereby are
subject to optional redemption under the conditions and on the terms set forth
in the Original Indenture at a price equal to the Redemption Price plus the
Make-Whole Premium.

                  (b) Mandatory Redemption. Subject to the provisions of Section
8.3 of the Original Indenture, the Bonds of each series created hereby are
subject to mandatory redemption under the conditions and on the terms set forth
in the Original Indenture at a price equal to the Redemption Price, but without
a Make-Whole Premium.

                  SECTION 2.7. Exchange Offer.

                  Any Initial Bonds which are presented to the Security
Registrar for exchange pursuant to an Exchange Offer in accordance with the
terms thereof shall be exchanged for Exchange Bonds of the same series and of
equal principal amount upon surrender to the Security Registrar of the Initial
Bonds to be exchanged; provided, however, that the Initial Bonds so surrendered
for exchange shall be duly endorsed and accompanied by a letter of transmittal
or written instrument of transfer in form satisfactory to the Company and the
Security Registrar, duly executed by the Holder thereof or its attorney who
shall be duly authorized in writing to execute such document. Whenever any
Initial Bonds are so surrendered for exchange, the Company shall execute, and
the Trustee shall authenticate and deliver to the Security Registrar, the same
aggregate principal amount of Exchange Bonds of the same series that have been
surrendered.

                  SECTION 2.8. Restrictions on Transfer and Exchange of Initial
Bonds.

                  (a) Initial Bonds in definitive form, all Global Bonds and all
beneficial interests in one or more Global Bonds, and all Bonds (other than
Exchange Bonds or Bonds sold pursuant

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   12

                                      -11-

to an effective registration statement) issued upon registration of transfer of,
or in exchange for, any such Bonds, shall be restricted securities (within the
meaning of Rule 144 under the Securities Act; hereinafter, collectively,
"Restricted Securities") and shall be subject to the restrictions on transfer
provided in the legend set forth on the Restricted Securities. The Holder of
each Restricted Security, by such Holder's acceptance thereof, agrees to be
bound by such restrictions on transfer. All Restricted Securities shall bear the
legend set forth on the face of the Restricted Securities.

                  Accredited Investors that are not QIBs may hold interests in
the Initial Bonds only in definitive form. Any beneficial interest in a Global
Bond that is a Restricted Security and is transferred to an Accredited Investor
which is not a QIB will be delivered in the form of a definitive Bond and will
cease to be an interest in such Global Bond.

                  A holder of a beneficial interest in a Global Bond may
exchange such beneficial interest for one or more definitive Bonds if (i) the
Issuer notifies the Trustee in writing that the Registered Depositary is
unwilling or unable to continue as depositary for such Global Bond, or the
Registered Depositary ceases to be a "Clearing Agency" registered under the
Exchange Act and a successor depositary is not appointed by the Issuer within 90
days of such notice or cessation or (ii) the Issuer, at its option, notifies the
Trustee in writing that it elects to cause the issuance of definitive Bonds. If
an exchange of a Global Bond for a definitive Bond is made pursuant to clauses
(i) or (ii) above, then, upon surrender by the Registered Depositary of any
beneficial interest in the Global Bonds, definitive Bonds will be issued to each
person that the Registered Depositary identifies as the beneficial owner of the
Bonds represented by the Global Bonds. Upon any such issuance, the Trustee will
be required to register such definitive Bonds in the name of such person or
persons (or nominee of any thereof) and cause the same to be delivered thereto.
Unless determined otherwise by the Company in accordance with applicable law,
each such Global Bond and all definitive Bonds, upon transfer or exchange of
beneficial interests in a Global Bond (other than for an Exchange Bond) will
bear the legend set forth on the face of the Restricted Securities.

                  Each Holder of a definitive Bond or a beneficial interest in a
Global Bond that is a Restricted Security will be deemed to have represented and
agreed to offer, sell, pledge or otherwise transfer such Initial Bonds or
beneficial interest only in accordance with the legend set forth on the face of
the Restricted Securities.

                  Upon the transfer, exchange or replacement of definitive Bonds
bearing the legend, or upon request for removal of the legend on a definitive
Bond, the Trustee will deliver Bonds that do not bear such legend if the Trustee
has been provided evidence satisfactory to the Company (which may include an
opinion of counsel) that neither the legend nor the restrictions on transfer set
forth therein are required to ensure compliance with the Securities Act.

                  Subject to the restrictions on transfer and exchange set forth
herein and in the Original Indenture, the holder of any Bond may transfer or
exchange such Bond in whole or in part (in a principal amount equal to the
minimum authorized denomination or any greater amount which is an integral
multiple of $1,000 or a lesser amount if the holder is transferring or

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   13

                                      -12-

exchanging all of the Bonds held by such holder) by surrendering it at the
Corporate Trust Office of the Trustee or at the office of the transfer agent,
together with (a) an executed instrument of assignment and transfer
substantially in the form set forth in Exhibit A to this First Supplemental
Indenture (in the case of a transfer) or a written request for exchange (in the
case of exchange) and (b) additional certifications and evidence that such
transfer or exchange is in compliance with the Securities Act and the
restrictions on transfer set forth in such Bond as may be required pursuant to
the terms of this First Supplemental Indenture.

                  Upon surrender of a definitive Bond for transfer or exchange
with the appropriate documentation, or notification of a request for transfer or
exchange of a beneficial interest in a Global Bond for a definitive Bond or
Bonds, subject to the restrictions described herein and in the Original
Indenture, the Trustee will, within five Business Days of such request if made
at the Corporate Trust Office of the Trustee, or within 10 Business Days if made
at the office of a transfer agent (other than the Trustee), authenticate and
deliver at the Corporate Trust Office of the Trustee or the office of the
transfer agent, as the case may be, to the transferee (in the case of transfer)
or Holder (in the case of exchange) or send by first class mail at the risk of
the transferee (in the case of transfer) or Holder (in the case of exchange) to
such address as the transferee or Holder, as applicable, may request, a
definitive Bond or Bonds, as the case may require, for a like aggregate
principal amount and in such authorized denomination or denominations as may be
requested. The presentation for transfer or exchange of any definitive Bond will
not be valid unless made at the Corporate Trust Office of the Trustee or at the
office of a transfer agent by the registered holder in person or by a duly
authorized attorney-in-fact. The Security Registrar is not required (a) to
issue, register the transfer of or exchange any Initial Bonds or any series
during a period beginning at the opening of business 15 days before the day of
the mailing of a notice of redemption of Bonds of such series selected for
redemption and ending at the close of business on the day of such mailing or (b)
to issue, register the transfer of or exchange any Initial Bond selected for
redemption in whole or in part except the unredeemed portion of any Initial Bond
selected for redemption in part. No service charge will be required of any
Holder participating in any transfer or exchange of Bonds in respect of such
transfer or exchange, but, with certain exceptions, payment may be required of
any tax or other governmental charges that may be imposed in connection
therewith.

                  (b) The following provisions shall apply with respect to any
proposed transfer of a Rule 144A Global Bond or a beneficial interest therein or
an Institutional Accredited Investor Bond prior to the expiration of the Resale
Restriction Termination Date:

                       (i)   a transfer of a Rule 144A Global Bond or a
       beneficial interest therein or an Institutional Accredited Investor Bond
       to a QIB shall be made upon the representation of the transferee that it
       is purchasing the Bond for its own account or an account with respect to
       which it exercises sole investment discretion and that it and any such
       account is a QIB and is aware that the sale to it is being made in
       reliance on Rule 144A and acknowledges that it has received such
       information regarding the Issuer and the Guarantors as the undersigned
       has requested pursuant to Rule 144A or has determined not to request such
       information and that it is aware that the transferor is

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   14

                                      -13-

       relying upon its foregoing representations in order to claim the
       exemption from registration provided by Rule 144A;

                       (ii)  a transfer of a Rule 144A Global Bond or a
       beneficial interest therein or an Institutional Accredited Investor Bond
       to an Institutional Accredited Investor shall be made upon receipt by the
       Trustee or its agent of a certificate substantially in the form set forth
       in Exhibit B annexed hereto from the proposed transferee and, if
       requested by the Issuer or the Trustee, the delivery of an opinion of
       counsel, certifications and/or other information satisfactory to each of
       them; and

                       (iii) a transfer of a Rule 144A Global Bond or a
       beneficial interest therein or an Institutional Accredited Investor Bond
       to a Non-U.S. Person shall be made upon receipt by the Trustee or its
       agent of a certificate substantially in the form set forth in Exhibit C
       annexed hereto from the proposed transferee and, if requested by the
       Issuer or the Trustee, the delivery of an opinion of counsel,
       certifications and/or other information satisfactory to each of them.

                  (c) The following provisions shall apply with respect to any
proposed transfer of a Regulation S Global Bond prior to the expiration of the
Distribution Compliance Period:

                       (i)   a transfer of a Regulation S Global Bond or a
       beneficial interest therein to a QIB shall be made upon the
       representation of the transferee that it is purchasing the Bond for its
       own account or an account with respect to which it exercises sole
       investment discretion and that it and any such account is a QIB and is
       aware that the sale to it is being made in reliance on Rule 144A and
       acknowledges that it has received such information regarding the Issuer
       and the Guarantors as the undersigned has requested pursuant to Rule 144A
       or has determined not to request such information and that it is aware
       that the transferor is relying upon its foregoing representations in
       order to claim the exemption from registration provided by Rule 144A;

                       (ii)  a transfer of a Regulation S Global Bond or a
       beneficial interest therein to an Institutional Accredited Investor shall
       be made upon receipt by the Trustee or its agent of a certificate
       substantially in the form set forth in Exhibit B annexed hereto from the
       proposed transferee and, if requested by the Issuer or the Trustee, the
       delivery of an opinion of counsel, certifications and/or other
       information satisfactory to each of them; and

                       (iii) a transfer of a Regulation S Global Bond or a
       beneficial interest therein to a Non-U.S. Person shall be made upon
       receipt by the Trustee or its agent of a certificate substantially
       in the form set forth in Exhibit C annexed hereto from the proposed
       transferee and, if requested by the Issuer or the Trustee, the delivery
       of an opinion of counsel, certifications and/or other information
       satisfactory to each of them.

                  Prior to or on the expiration of the Distribution Compliance
Period, beneficial interests in a Regulation S Global Bond may only be held
through Morgan Guaranty Trust Company of New York, Brussels Office, as operator
of the Euroclear System ("Euroclear") or

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   15

                                      -14-

Clearstream Banking, a societe anonyme ("Clearstream") (as indirect participants
in DTC) or another agent member of Euroclear and Clearstream acting for and on
behalf of them, unless exchanged for interests in the Rule 144A Global Bond in
accordance with the certification requirements hereof. During the Distribution
Compliance Period, interests in the Regulation S Global Bond, if any, may be
exchanged for interests in the Rule 144A Global Bond or for definitive bonds
only in accordance with the certification requirements described in this Section
2.8.

                  After the expiration of the Distribution Compliance Period,
interests in the Regulation S Global Bond may be transferred without requiring
the certification set forth in Exhibit C annexed hereto or any additional
certification.

                  As used in the preceding two paragraphs of this Section 2.8,
the term "transfer" encompasses any sale, transfer or other disposition of any
Bonds referred to herein except for transfers from any Holder to an Affiliate of
such Holder; provided, that such transferring Holder shall deliver a letter to
the Trustee stating that the transferee is an Affiliate of such Holder. The
Trustee shall be entitled to rely on and be fully protected in its reliance on
such letter.

                                  ARTICLE III

                                  MISCELLANEOUS

                  SECTION 3.1. Execution of Supplemental Indenture.

                  This First Supplemental Indenture is executed and shall be
construed as an indenture supplemental to the Original Indenture and, as
provided in the Original Indenture, this First Supplemental Indenture forms a
part thereof.

                  SECTION 3.2. Concerning the Trustee.

                  The recitals contained herein and in the Bonds of each series
created hereby, except with respect to the Trustee's certificates of
authentication, shall be taken as the statements of the Company and the Trustee
assumes no responsibility for the correctness of same. The Trustee makes no
representations as to the validity or sufficiency of this First Supplemental
Indenture or of the Bonds of each series created hereby.

                  SECTION 3.3. Counterparts.

                  This First Supplemental Indenture may be executed in any
number of counterparts, each of which when so executed shall be deemed to be an
original, but all such counterparts shall together constitute but one of the
same instrument.

                  SECTION 3.4. GOVERNING LAW.

                  THIS FIRST SUPPLEMENTAL INDENTURE AND EACH BOND OF A SERIES
CREATED HEREUNDER SHALL BE GOVERNED BY, AND CONSTRUED IN

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   16

                                      -15-

ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO PRINCIPLES
OF CONFLICTS OF LAW THEREOF TO THE EXTENT THE APPLICATION OF SUCH PRINCIPLES
WOULD CAUSE THE APPLICATION OF THE LAWS OF ANY OTHER JURISDICTION.

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   17

                                      -16-

                  IN WITNESS WHEREOF, the parties have caused this First
Supplemental Indenture to be duly executed by their respective officers
thereunto duly authorized as of the day and year first above written.

                                         NRG NORTHEAST GENERATING LLC

                                         By:/s/ Craig Mataczynski
                                            ----------------------------
                                            Name:  Craig Mataczynski
                                            Title: President

                                         ARTHUR KILL POWER LLC

                                         By: /s/ Brian B. Bird
                                            ----------------------------
                                            Name:  Brian B. Bird
                                            Title: Treasurer

                                         ASTORIA GAS TURBINE POWER LLC

                                         By: /s/ Brian B. Bird
                                            ----------------------------
                                            Name:  Brian B. Bird
                                            Title: Treasurer

                                         CONNECTICUT JET POWER LLC

                                         By: /s/ Brian B. Bird
                                            ----------------------------
                                            Name:  Brian B. Bird
                                            Title: Treasurer

                                         DEVON POWER LLC

                                         By: /s/ Brian B. Bird
                                            ----------------------------
                                            Name:  Brian B. Bird
                                            Title: Treasurer

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   18

                                      -17-

                                         DUNKIRK POWER LLC

                                         By: /s/ Brian B. Bird
                                            ----------------------------
                                            Name:  Brian B. Bird
                                            Title: Treasurer

                                         HUNTLEY POWER LLC

                                         By: /s/ Brian B. Bird
                                            ----------------------------
                                            Name:  Brian B. Bird
                                            Title: Treasurer

                                         MIDDLETOWN POWER LLC

                                         By: /s/ Brian B. Bird
                                            ----------------------------
                                            Name:  Brian B. Bird
                                            Title: Treasurer

                                         MONTVILLE POWER LLC

                                         By: /s/ Brian B. Bird
                                            ----------------------------
                                            Name:  Brian B. Bird
                                            Title: Treasurer

                                         NORWALK POWER LLC

                                         By: /s/ Brian B. Bird
                                            ----------------------------
                                            Name:  Brian B. Bird
                                            Title: Treasurer

                                         OSWEGO HARBOR POWER LLC

                                         By: /s/ Brian B. Bird
                                            ----------------------------
                                            Name:  Brian B. Bird
                                            Title: Treasurer

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   19

                                      -18-

                                         SOMERSET POWER LLC

                                         By: /s/ Brian B. Bird
                                            ----------------------------
                                            Name:  Brian B. Bird
                                            Title: Treasurer

                                         THE CHASE MANHATTAN BANK,

                                         By: /s/ Annette M. Marsula
                                            ----------------------------
                                            Name:  Annette M. Marsula
                                            Title: Vice President

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   20

                                                                       EXHIBIT A

                        [Form of Transferor Certificate]

                   CERTIFICATE TO NRG NORTHEAST GENERATING LLC
                                   AND TRUSTEE

                          __% SERIES [ ] BONDS DUE [ ]

                  This is to certify that as of the date hereof with respect to
U.S. $ ______________________ principal amount of the above-captioned securities
presented or surrendered on the date hereof (the "Surrendered Bonds") for
registration of transfer or for exchange where the securities issuable upon such
exchange are to be registered in a name other than that of the undersigned
Holder (each such transaction being a "transfer"), the undersigned Holder (as
defined in the Indenture) of the Surrendered Bonds represents and certifies for
the benefit of NRG Northeast Generating LLC and The Chase Manhattan Bank, as
Trustee, that the transfer of Surrendered Bonds associated with such transfer
complies with the restrictive legend set forth on the face of the Surrendered
Bonds for the reason checked below:

[ ]    The Surrendered Bonds are being transferred to a person whom we
       reasonably believe is a "qualified institutional buyer" (as defined in
       Rule 144A under the Securities Act of 1933) (a "QIB") that purchases for
       its own account or for the account of a QIB to whom notice is given that
       the resale, pledge or transfer is being made in reliance on Rule 144A
       under the Securities Act; or

[ ]    The Surrendered Bonds are being transferred to an institution that is
       an "accredited investor" meeting the requirements of Rule 501(a)(1), (2),
       (3) or (7) under the Securities Act that is acquiring the Surrendered
       Bonds for investment purposes and not for distribution;(1) or

[ ]    The transfer of the Surrendered Bonds complies with Rule 144 under the
       Securities Act;(2) or

[ ]    The transfer of the Surrendered Bonds complies with another applicable
       exemption from the registration requirements of the Securities Act.(2)

                                                 -----------------------------
                                                 [Name of Holder]

Dated:  __________, ____
[To be dated the date of presentation or surrender]

1.     These transfers require that the transferee deliver a letter
       substantially in the form of Exhibit B to the First Supplemental
       Indenture dated as of February 22, 2000 and may also require an opinion
       of counsel.

2.     These transfers may require an opinion of counsel.

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   21

                                                                       EXHIBIT B

                        [Form of Institutional Accredited
                     Investor Transferee Compliance Letter]

NRG Northeast Generating LLC
1221 Nicollet Mall
Suite 700
Minneapolis, MN  55403-2445
Attention:  Investor Relations

The Chase Manhattan Bank
450 W. 33rd Street, 15th Floor
New York, New York  10001
Attention: Capital Market Fiduciary Services

Dear Ladies and Gentlemen:

                  In connection with our proposed purchase of $__________
aggregate principal amount of ____ % Series ____ Senior Secured Bonds Due
_______ (the "Bonds") of NRG Northeast Generating LLC, a Delaware limited
liability company (the "Company"), we confirm that

                  1.   We understand that the Bonds have not been registered
       under the Securities Act of 1933 (the "Securities Act") and may not be
       sold except as permitted in the following sentence. We agree, on our own
       behalf and on behalf of any accounts for which we are acting as
       hereinafter stated, to offer, sell, pledge or otherwise transfer such
       Bonds prior to the date which is two years after the later of the
       original issue date of the Bonds and the last date on which the Company
       or any affiliate of the Company was the owner of the Bond (or any
       predecessor of such Bond), only (i) to the Company, (ii) so long as such
       Bonds are eligible for resale pursuant to Rule 144A under the Securities
       Act ("Rule 144A"), to a person whom we reasonably believe is a "qualified
       institutional buyer" (as defined in Rule 144A) (a "QIB") that purchases
       for its own account or for the account of a QIB to whom notice is given
       that the resale, pledge or transfer is being made in reliance on Rule
       144A (as indicated by the box checked by the transferor on the Transferor
       Certificate, a form of which is attached as Exhibit A to the First
       Supplemental Indenture relating to the Bonds, dated as of 2004, 2010 and
       2024, as the case may be), (iii) to an institution that is an "accredited
       investor" as defined in Rule 501(a)(1), (2), (3) or (7) under the
       Securities Act (as indicated by the box checked by the transferor on the
       Transferor Certificate, a form of which is attached as Exhibit A to the
       First Supplemental Indenture relating to the Bonds, dated as of 2004,
       2010 and 2024, as the case may be) that is acquiring the Bonds in a
       minimum amount of $250,000 for investment purposes and not for
       distribution and an Institutional Accredited Investor Transferee
       Compliance Letter in the form hereof is delivered to the Company and to
       the Trustee under the Indenture relating to the Bonds by such accredited
       investor, (iv) pursuant to any other available

<PAGE>   22

       exemption from registration under the Securities Act, or (v) pursuant to
       an effective registration statement under the Securities Act, in each
       case in accordance with any applicable securities laws of any state of
       the United States, and we will notify any purchaser of the Bonds from us
       of the above resale restrictions, if then applicable. We further
       understand that in connection with any transfer of the Bonds by us that
       the Company and the Trustee may request, and if so requested we will
       furnish, such opinions of counsel, certificates and/or other information
       as they may reasonably require to confirm that any such transfer complies
       with the foregoing restrictions.

                  2.   We are an institutional investor and are an "accredited
       investor" (as defined in Rule 501(a)(1), (2), (3) or (7) under the
       Securities Act) and we have such knowledge and experience in financial
       and business matters as to be capable of evaluating the merits and
       risks of our investment in the Bonds, and we and any accounts for which
       we are acting are each able to bear the economic risk of our or its
       investment.

                  3.   We understand that the Bonds will be issued solely in
       physical certificated form (and not in the form of interests in
       securities deposited with The Depository Trust Company) and the minimum
       principal amount of Bonds that may be purchased by an institutional
       accredited investor is $250,000.

                  4.   We are acquiring the Bonds purchased by us for our own
       account or for one or more accounts as to each of which we exercise
       sole investment discretion.

                  5.   You are entitled to rely upon this letter and you are
       irrevocably authorized to produce this letter or a copy hereof to any
       interested party in any administrative or legal proceeding or official
       inquiry with respect to the matters covered hereby.

                                                 Very truly yours,

                                                 ----------------------------
                                                 (Name of Purchaser)
                                                 By:
                                                    -------------------------

Date:
     ---------------

<PAGE>   23

                                                                       EXHIBIT C

                   [Form of Regulation S Transfer Certificate]

                                                                          [date]

NRG Northeast Generating LLC
1221 Nicollet Mall
Suite 700
Minneapolis, MN  55403-2445
Attention:  Investor Relations

The Chase Manhattan Bank
450 W. 33rd Street, 15th Floor
New York, New York  10001
Attention: Capital Market Fiduciary Services

Dear Ladies and Gentlemen:

                  In connection with our proposed purchase of $__________
aggregate principal amount of ____ % Series ____ Senior Secured Bonds Due
_______ (the "Bonds") of NRG Northeast Generating LLC, a Delaware limited
liability company (the "Company"), we confirm that:

           (a)    the offer of the Bonds was not made to a person in the
                  United States;

           (b)    either (i) at the time the buy order was originated, the
                  transferee was outside the United States or we and any
                  person acting on our behalf reasonably believed that the
                  transferee was outside the United States or (ii) the
                  transaction was executed in, on or through the facilities
                  of a designated off-shore securities market and neither we
                  nor any person acting on our behalf knows that the
                  transaction has been pre-arranged with a buyer in the
                  United States;

           (c)    no directed selling efforts have been made in the United
                  States in contravention of the requirements of Rule 903(b)
                  or Rule 904(b) of Regulation S, as applicable; and

           (d)    the transaction is not part of a plan or scheme to evade
                  the registration requirements of the Securities Act.

                  In addition, if the sale is made during a Distribution
Compliance Period and the provisions of Rule 903(c)(3) or Rule 904(c)(1) of
Regulation S are applicable thereto, we confirm that such sale has been made in
accordance with the applicable provisions of Rule 903(c)(3) or Rule 904(c)(1),
as the case may be.

<PAGE>   24

                  The Company and the Trustee are entitled to rely upon this
letter and are irrevocably authorized to produce this letter or a copy hereof to
any interested party in any administrative or legal proceedings or official
inquiry with respect to the matters covered hereby. Terms used in this
certificate have the meanings set forth in Regulation S.

Very truly yours,

[Name of Transferor]

By:
   ---------------------------------           -------------------------------
     Authorized Signature                      Signature Medallion Guaranteed

<PAGE>   25

                                                           Schedule 1-A to First
                                                       Supplemental Indenture to
                                              NRG Northeast Generating Indenture

                           [Form of face of definitive
                 8.065% Series A Senior Secured Bonds Due 2004]

                          NRG NORTHEAST GENERATING LLC
                  8.065% SERIES A SENIOR SECURED BOND DUE 2004

                  THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT
OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR THE SECURITIES LAWS OF ANY STATE
OR OTHER JURISDICTION. NEITHER THIS SECURITY NOR ANY INTEREST OR PARTICIPATION
HEREIN MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR
OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH
TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, SUCH REGISTRATION.

                  THE HOLDER OF THIS SECURITY BY ITS ACCEPTANCE HEREOF AGREES TO
OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE "RESALE
RESTRICTION TERMINATION DATE") WHICH IS TWO YEARS AFTER THE LATER OF THE
ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH THE ISSUER OR ANY
AFFILIATE OF THE ISSUER WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF
SUCH SECURITY), ONLY (A) TO THE ISSUER, (B) PURSUANT TO A REGISTRATION STATEMENT
THAT HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT, (C) FOR SO LONG AS
THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THE
SECURITIES ACT ("RULE 144A"), TO A PERSON IT REASONABLY BELIEVES IS A "QUALIFIED
INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A THAT PURCHASES FOR ITS OWN ACCOUNT
OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN
THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (D) PURSUANT TO OFFERS
AND SALES THAT OCCUR OUTSIDE THE UNITED STATES WITHIN THE MEANING OF REGULATION
S UNDER THE SECURITIES ACT, (E) TO AN INSTITUTIONAL "ACCREDITED INVESTOR" WITHIN
THE MEANING OF RULE 501(a)(1), (2), (3) OR (7) UNDER THE SECURITIES ACT THAT IS
AN INSTITUTIONAL INVESTOR ACQUIRING THE SECURITY FOR ITS OWN ACCOUNT OR FOR THE
ACCOUNT OF SUCH AN INSTITUTIONAL ACCREDITED INVESTOR, IN EACH CASE IN A MINIMUM
PRINCIPAL AMOUNT OF THE SECURITIES OF $250,000, FOR INVESTMENT PURPOSES AND NOT
WITH A VIEW TO OR FOR OFFER OR SALE IN CONNECTION WITH ANY DISTRIBUTION IN
VIOLATION OF THE SECURITIES ACT OR (F) PURSUANT TO ANY OTHER AVAILABLE EXEMPTION
FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE
ISSUER'S AND THE TRUSTEE'S RIGHTS PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER
PURSUANT TO CLAUSES (D), (E) OR (F) TO REQUIRE THE DELIVERY OF AN OPINION OF
COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO

<PAGE>   26

EACH OF THEM AND IN THE CASE OF THE FOREGOING CLAUSE (E), A CERTIFICATE OF
TRANSFER (A FORM OF WHICH MAY BE OBTAINED FROM THE ISSUER OR THE TRUSTEE)
COMPLETED AND DELIVERED BY THE TRANSFEROR TO THE ISSUER AND THE TRUSTEE. THIS
LEGEND WILL BE REMOVED UPON THE REQUEST OF THE HOLDER AFTER THE RESALE
RESTRICTION TERMINATION DATE.

                                       2

<PAGE>   27

No.                                                                 CUSIP NUMBER
                                                                       [    ]

Principal Amount         Final Scheduled Payment Date       Issue Date
----------------         ----------------------------       ----------
$[___________]                 December 15, 2004            February 22, 2000

         REGISTERED HOLDER:         [_______________]

         PRINCIPAL AMOUNT:          [_______________] Dollars

         INTEREST RATE:             8.065%

                  NRG NORTHEAST GENERATING LLC, a Delaware limited liability
company (hereinafter called the "Company", which term includes any successor or
assign under the Indenture referred to below), for value received hereby
promises to pay to [____________], or its registered assigns, the outstanding
Principal Amount hereof, such payment to be made in semiannual installments on
June 15 and December 15 of each year (commencing December 15, 2000) and ending
on the final Scheduled Payment Date set forth above, each such installment to be
in the amount and payable on the date set forth on Annex A attached hereto
(provided that the portion of the Principal Amount remaining unpaid on the final
Scheduled Payment Date, together with all interest accrued thereon, shall in any
and all cases be due and payable on the final Scheduled Payment Date), and to
pay interest on the unpaid portion of the Principal Amount at the interest rate
set forth above (subject to the fourteenth paragraph set forth on the reverse of
this Bond, which refers to a Registration Default) from the most recent
Scheduled Payment Date to which interest has been paid or duly provided for or,
if no interest has been paid or duly provided for, from the issue date set forth
above, semiannually on June 15 and December 15 in each year (commencing June 15,
2000) until the Principal Amount is paid in full or payment thereof is duly
provided for. Any installment of principal and, to the extent permitted by
applicable law, any payment of interest not punctually paid or duly provided for
shall continue to bear interest at a rate equal to the interest rate set forth
above. The principal and interest so payable, and punctually paid or duly
provided for, at any Scheduled Payment Date shall, as provided in the Indenture,
be paid to the Person in whose name this Bond (or one or more Predecessor Bonds)
is registered in the Security Register at the close of business on the Regular
Record Date for such payment of principal and interest, which shall be June 1 or
December 1, as the case may be (whether or not a Business Day), next preceding
such Scheduled Payment Date. Any such principal and interest that is payable,
but is not so punctually paid or duly provided for at any Scheduled Payment
Date, shall forthwith cease to be payable to the Holder hereof on such Regular
Record Date, and may be paid to the Person in whose name this Bond (or one or
more Predecessor Bonds) is registered at the close of business on a Special
Record Date for the payment of such defaulted principal and interest (together
with any other amounts payable with respect to such principal and interest), to
be fixed by the Trustee, notice of which shall be given to the Holder hereof not
less than 10 days prior to such Special Record Date, or may be paid at any time
in any other lawful manner not inconsistent with the requirements of any
securities exchange on which this Bond may be listed, and upon such notice as
may be required by such

                                       3

<PAGE>   28

exchange, all as more fully provided in the Indenture. Payments of principal of
and interest on this Bond shall be made (i) if the Company so elects, by check
mailed to the Holder at his or her registered address or (ii) otherwise, at the
Place of Payment; provided, that the final installment of principal payable with
respect to this Bond shall be made as provided in Section 8.5 of the Indenture
(in the event this Bond is redeemed) or shall be made upon presentation and
surrender of this Bond at the Place of Payment. All payments in respect of this
Bond shall be made in such coin or currency of the United States of America as
at the time of payment is legal tender for payment of debts.

                  Whenever any amount to be paid hereunder is stated to be due
on a day that is not a Business Day, such amount shall be payable on the next
succeeding Business Day and if such payment is timely made, no interest shall
accrue for the period from and after the day on which such payment was due.
Interest payments for this Bond will be computed and paid on the basis of a
360-day year consisting of twelve 30-day months.

                  Reference is made to the further provisions of this Bond set
forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if set forth at this place.

                  Unless the certificate of authentication hereon has been
executed by the Trustee by manual signature, this Bond shall not be entitled to
any benefit under the Indenture, or be valid or obligatory for any purpose.

                  IN WITNESS WHEREOF, the Company has caused this instrument to
be duly executed.

                                              NRG NORTHEAST GENERATING LLC

                                              By
                                                ----------------------------
                                               Name:
                                               Title:

                                        4

<PAGE>   29

                          CERTIFICATE OF AUTHENTICATION

                  This Bond is one of the Bonds referred to in the
within-mentioned Indenture.

THE CHASE MANHATTAN BANK,
   as Trustee

By:
   -------------------------------
   Authorized Signatory

                                       5

<PAGE>   30

                         [Form of reverse of definitive
                 8.065% Series A Senior Secured Bonds Due 2004]

                          NRG NORTHEAST GENERATING LLC
                  8.065% SERIES A SENIOR SECURED BOND DUE 2004

                  This bond is one of an authorized issue of Bonds of the
Company known as its 8.065% Series A Senior Secured Bonds Due 2004 (the
"Bonds"). The Bonds are issued under the Indenture dated as of February 22, 2000
(the "Original Indenture") among the Company, the Guarantors party thereto and
The Chase Manhattan Bank, a New York banking corporation, as trustee (in such
capacity, together with its successors in such capacity, the "Trustee"), as
supplemented by the First Supplemental Indenture dated as of February 22, 2000
(the "First Supplemental Indenture") among the Company, the Guarantors party
thereto and the Trustee (the Original Indenture, as so supplemented, and as the
same may be amended, modified and further supplemented, the "Indenture"). All
capitalized terms used herein, unless otherwise defined herein, shall have the
meanings ascribed to them in the Indenture.

                  All Bonds of any series issued and Outstanding under the
Indenture rank on a parity with each other Bond of the same series and with all
Bonds of each other series. Reference is hereby made to the Indenture for a
description of the nature and extent of the Bonds and the respective rights,
limitations of rights, duties and immunities thereunder of the Holders and of
the Trustee and the Company in respect of the Bonds and the terms upon which the
Bonds are made and are to be authenticated and delivered.

                  The principal of and interest on, this Bond are (i) guaranteed
by the Guarantors and (ii) secured by assets subject to the Lien of the
Collateral Documents, and all payments of principal and interest shall be made
in accordance with the terms of the Indenture. Each Holder, by acceptance of
this Bond, hereby acknowledges and agrees that (a) subject to the terms of
Section 10.2 of the Original Indenture, it will look solely to the assets of the
Company, the other Collateral purported to be covered under the Collateral
Documents and the income and proceeds received by the Trustee therefrom to the
extent available for distribution to such Holder as herein provided or provided
in the Collateral Documents, (b) none of the Members, or any of their respective
past, present or future members, officers, partners, directors or shareholders
or other Related Persons, or the Trustee shall be personally or otherwise liable
to any Holder, nor shall the Members, nor any of their respective past, present
or future members, officers, partners, directors or shareholders or other
Related Persons, be personally or otherwise liable to the Trustee for any
amounts payable under any Bond or for any liability under the Indenture or any
other Transaction Document, except as provided in the Original Indenture and (c)
recourse for any such amounts payable shall be otherwise limited in accordance
with Section 2.14 and Section 17.1 of the Original Indenture.

                  The obligations of the Company to pay the principal of and
interest on the Bonds when due as herein prescribed are absolute and
unconditional and no provision of this Bond or the Indenture shall alter or
impair such obligations.

                  The Bonds are subject to a Security Agreement dated as of
February 22, 2000 pursuant to which the rights of the Secured Parties (including
the Holders and the Trustee) in

                                        6

<PAGE>   31

respect of the Collateral will be shared among the Secured Parties and will be
exercised by the Collateral Agent in accordance with the Security Agreement.

                  The Indenture permits, with certain exceptions, as therein
provided, the amendment thereof and the modification of the rights and
obligations of the Company and the rights of the Holder under the Indenture at
any time by the Company with the consent of the Holders of not less than a
majority in aggregate principal amount of the Bonds of all series then
Outstanding. The Indenture also contains provisions permitting the Holders of
specified percentages in aggregate principal amount of the Bonds of all series
then Outstanding, on behalf of the Holders of all the Bonds, to waive compliance
by the Company with certain provisions of the Indenture and certain past
defaults under the Indenture and their consequences. Any Act (as such term is
defined in the Indenture), including, but not limited to, such a consent, waiver
or direction by the Holder of this Bond shall be conclusive and binding upon the
Holder and upon all future Holders of this Bond and the Holder of every Bond
issued upon the transfer hereof or the exchange herefor or in lieu hereof
whether or not notation of such Act is made upon this Bond.

                  This Bond is one of the series designated on the face hereof,
limited to $320,000,000 in aggregate principal amount as provided in the First
Supplemental Indenture.

                  This Bond and all Bonds issued or to be issued in series
created under the First Supplemental Indenture are (i) redeemable at the option
of the Company in accordance with Section 8.2 of the Indenture, on not less than
30 nor more than 60 days' notice, at a redemption price equal to the principal
amount thereof plus unpaid and accrued interest plus the Make-Whole Premium and
(ii) not subject to any sinking fund.

                  The Bonds are, under certain conditions, subject to mandatory
redemption as set forth in Section 8.3 of the Indenture. Notice of any
redemption of Bonds will be given at least 30 days but not more than 60 days
before the Redemption Date to each Holder at its address as it appears in the
Security Register.

                  Bonds (or portions thereof as aforesaid) for the redemption of
which provision is made in accordance with the Indenture shall cease to bear
interest from and after any Redemption Date.

                  The Indenture contains provisions for, upon compliance by the
Company with certain conditions set forth in the Indenture, the defeasance of
(a) the entire indebtedness of this Bond and (b) certain restrictive covenants
and agreements.

                  The unpaid portion of the Principal Amount, together with any
interest accrued and unpaid thereon and all other amounts due hereunder, if any,
may become due and payable upon the occurrence and continuation of any Event of
Default, but only as provided in the Indenture.

                  The Company and the Guarantors have entered into an Exchange
and Registration Rights Agreement dated February 15, 2000 (the "Registration
Rights Agreement") with the Initial Purchasers described therein. Pursuant to
such Registration Rights Agreement, the Company and the Guarantors have agreed
to file with the SEC a registration statement under the

                                        7

<PAGE>   32

Securities Act ("Registration Statement") for an offer to exchange the Bonds for
a like aggregate principal amount of Bonds issued pursuant to the Indenture that
are in all material respects identical to the Bonds except that such exchange
Bonds shall be issued pursuant to an effective Registration Statement.

                  From and after the date on which a Registration Default (as
defined in the Registration Rights Agreement) occurs, the interest rate payable
on this Bond shall increase (in addition to the interest rate set forth above)
and additional interest reflecting such increase shall accrue with respect to
this Bond, until but not including the date on which such Registration Default
shall cease to exist (and provided no other Registration Default with respect to
this Bond shall then be continuing), at the rate of one half of one percent
(0.50%) per annum, which additional interest shall be payable hereon at the
times, in the manner and subject to the same terms and conditions set forth
herein and in the Indenture, as though the interest rate set forth above had
been increased by one half of one percent (0.50%) per annum.

                  The Bonds are issuable only as registered Bonds without
coupons in minimum denominations of $100,000 and any integral multiple of $1,000
in excess thereof. As provided in, and subject to the provisions of, the
Indenture, Bonds are exchangeable at the option of the Holder thereof for other
Bonds of the same series, of authorized denomination and of like tenor,
maturity, interest rate and aggregate principal amount, to be registered in the
name of such Holder, upon surrender thereof by such Holder at any office or
agency maintained for such purpose pursuant to the Indenture.

                  No service charge will be required of any Holder participating
in any such transfer or exchange of Bonds in respect of such transfer or
exchange, but the Security Registrar may require payment of a sum sufficient to
cover any tax or other governmental charge payable in connection therewith.

                  The person in whose name this Bond is registered shall be
deemed to be the owner and holder hereof for the purpose of receiving payment as
herein provided and for all other purposes whether or not this Bond be overdue
regardless of any notice to anyone to the contrary.

                  Bonds actually known to a Responsible Officer of the Trustee
to be owned or held by, or for the account or benefit of, the Company, the
Guarantors, or an Affiliate of any of the foregoing shall not be entitled to
share in any payment or distribution provided for in Article 10 of the Indenture
until all Bonds held by other Persons have been indefeasibly paid in full.

                  THIS BOND SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE
WITH, THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO PRINCIPLES OF
CONFLICTS OF LAW THEREOF TO THE EXTENT THE APPLICATION OF SUCH PRINCIPLES WOULD
CAUSE THE APPLICATION OF THE LAWS OF ANY OTHER JURISDICTION.

                                        8

<PAGE>   33

                                                                      ANNEX A TO
                                    8.065% SERIES A SENIOR SECURED BOND DUE 2004

                  The following table sets forth the date of each semiannual
installment of the aggregate principal to be paid on all Bonds of this series on
each such date:

<TABLE>
<CAPTION>
                                                            PRINCIPAL
                                                               AMOUNT
                           PRINCIPAL                          PAYABLE
                             PAYMENT                        ON SERIES
                               DATES                          A BONDS
                             -------                        ---------

<S>                                                    <C>
                   December 15, 2000                      $50,000,000
                       June 15, 2001                       45,000,000
                   December 15, 2001                       45,000,000
                       June 15, 2002                       53,500,000
                   December 15, 2002                       53,500,000
                       June 15, 2003                       17,500,000
                   December 15, 2003                       17,500,000
                       June 15, 2004                       19,000,000
                   December 15, 2004                       19,000,000
                               TOTAL                     $320,000,000

</TABLE>

                                       9

<PAGE>   34

                                  ABBREVIATIONS

                  The following abbreviations when used in the inscription on
the face of this instrument shall be construed as though they were written out
in full according to applicable laws or regulations:

         TEN COM  --       as tenants in common
         TEN ENT  --       as tenants by the entireties
          JT TEN  --       as joint tenants with right of
                           survivorship and not as tenants in
                           common

                        UNIF GIFT MIN ACT
                                         --------------------------------------
                                                     (Cust)   (Minor)

                                         under Uniform Gift to Minors Act

                                         --------------------------------------
                                                       (State)

                Additional abbreviations may also be used though
                              not in the above list

                               -------------------

                                       10

<PAGE>   35

                  FOR VALUE-RECEIVED the undersigned hereby sell(s), assign(s)
and transfer(s) unto

Identifying Number of Assignee
                              --------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
                  (Please print or typewrite name and address,
                         including zip code of Assignee)

the within Bond and all rights thereunder, hereby irrevocably constituting and
appointing _________ attorney to transfer said Bond on the books of the Company,
with full power of substitution in the premises.

Dated:
      -------------------

                                                 ------------------------------
                                                 NAME:

NOTICE: The signature to this assignment must correspond with the name as
        written upon the first page of the within instrument in every
        particular, without alteration or enlargement or any change whatsoever.

                                       11

<PAGE>   36

                                                           Schedule 1-B to First
                                                          Supplemental Indenture

                          [Form of face of Global Bond
               for 8.065% Series A Senior Secured Bonds Due 2004]

                          NRG NORTHEAST GENERATING LLC
                  8.065% SERIES A SENIOR SECURED BOND DUE 2004

                  [Insert in Rule 144A Global Bonds -- THIS SECURITY HAS NOT
BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES
ACT"), OR THE SECURITIES LAWS OF ANY STATE OR OTHER JURISDICTION. NEITHER THIS
SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN MAY BE REOFFERED, SOLD,
ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE
ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT
SUBJECT TO, SUCH REGISTRATION.

                  THE HOLDER OF THIS SECURITY BY ITS ACCEPTANCE HEREOF AGREES TO
OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE "RESALE
RESTRICTION TERMINATION DATE") WHICH IS TWO YEARS AFTER THE LATER OF THE
ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH THE ISSUER OR ANY
AFFILIATE OF THE ISSUER WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF
SUCH SECURITY), ONLY (A) TO THE ISSUER, (B) PURSUANT TO A REGISTRATION STATEMENT
THAT HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT, (C) FOR SO LONG AS
THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THE
SECURITIES ACT ("RULE 144A"), TO A PERSON IT REASONABLY BELIEVES IS A "QUALIFIED
INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A THAT PURCHASES FOR ITS OWN ACCOUNT
OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN
THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (D) PURSUANT TO OFFERS
AND SALES THAT OCCUR OUTSIDE THE UNITED STATES WITHIN THE MEANING OF REGULATION
S UNDER THE SECURITIES ACT, (E) TO AN INSTITUTIONAL "ACCREDITED INVESTOR" WITHIN
THE MEANING OF RULE 501(a)(1), (2), (3) OR (7) UNDER THE SECURITIES ACT THAT IS
AN INSTITUTIONAL INVESTOR ACQUIRING THE SECURITY FOR ITS OWN ACCOUNT OR FOR THE
ACCOUNT OF SUCH AN INSTITUTIONAL ACCREDITED INVESTOR, IN EACH CASE IN A MINIMUM
PRINCIPAL AMOUNT OF THE SECURITIES OF $250,000, FOR INVESTMENT PURPOSES AND NOT
WITH A VIEW TO OR FOR OFFER OR SALE IN CONNECTION WITH ANY DISTRIBUTION IN
VIOLATION OF THE SECURITIES ACT OR (F) PURSUANT TO ANOTHER AVAILABLE EXEMPTION
FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE
ISSUER'S AND THE TRUSTEE'S RIGHTS PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER
PURSUANT

<PAGE>   37

TO CLAUSES (D), (E) OR (F) TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL,
CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO EACH OF THEM AND IN THE
CASE OF THE FOREGOING CLAUSE (E), A CERTIFICATE OF TRANSFER (A FORM OF WHICH MAY
BE OBTAINED FROM THE ISSUER OR THE TRUSTEE) COMPLETED AND DELIVERED BY THE
TRANSFEROR TO THE ISSUER AND THE TRUSTEE. THIS LEGEND WILL BE REMOVED UPON THE
REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE.]

                  [Insert in Regulation S Global Bonds -- THIS SECURITY HAS NOT
BEEN REGISTERED UNDER THE UNITED STATES SECURITIES ACT OF 1933, AS AMENDED (THE
"SECURITIES ACT"), AND ACCORDINGLY, MAY NOT BE OFFERED OR SOLD WITHIN THE UNITED
STATES OR TO OR FOR THE ACCOUNT OR BENEFIT OF, U.S. PERSONS EXCEPT AS SET FORTH
IN THE FOLLOWING SENTENCE. BY ITS ACQUISITION HEREOF, THE HOLDER (1) REPRESENTS
THAT IT IS NOT A U.S. PERSON AND IS ACQUIRING THIS SECURITY IN AN OFFSHORE
TRANSACTION, (2) BY ITS ACCEPTANCE HEREOF AGREES TO OFFER, SELL OR OTHERWISE
TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE "RESALE RESTRICTION TERMINATION
DATE") WHICH IS TWO YEARS AFTER THE LATER OF THE ORIGINAL ISSUE DATE HEREOF AND
THE LAST DATE ON WHICH THE ISSUER OR ANY AFFILIATE OF THE ISSUER WAS THE OWNER
OF THIS SECURITY (OR ANY PREDECESSOR OF SUCH SECURITY), ONLY (A) TO THE ISSUER,
(B) PURSUANT TO A REGISTRATION STATEMENT THAT HAS BEEN DECLARED EFFECTIVE UNDER
THE SECURITIES ACT, (C) FOR SO LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE
PURSUANT TO RULE 144A UNDER THE SECURITIES ACT ("RULE 144A"), TO A PERSON IT
REASONABLY BELIEVES IS A "QUALIFIED INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A
THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED
INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN
RELIANCE ON RULE 144A, (D) PURSUANT TO OFFERS AND SALES THAT OCCUR OUTSIDE THE
UNITED STATES WITHIN THE MEANING OF REGULATION S UNDER THE SECURITIES ACT, (E)
TO AN INSTITUTIONAL "ACCREDITED INVESTOR" WITHIN THE MEANING OF RULE 501(a)(1),
(2), (3) OR (7) UNDER THE SECURITIES ACT THAT IS AN INSTITUTIONAL INVESTOR
ACQUIRING THE SECURITY FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF SUCH AN
INSTITUTIONAL ACCREDITED INVESTOR, IN EACH CASE IN A MINIMUM PRINCIPAL AMOUNT OF
THE SECURITIES OF $250,000, FOR INVESTMENT PURPOSES AND NOT WITH A VIEW TO OR
FOR OFFER OR SALE IN CONNECTION WITH ANY DISTRIBUTION IN VIOLATION OF THE
SECURITIES ACT OR (F) PURSUANT TO ANOTHER AVAILABLE EXEMPTION FROM THE
REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE ISSUER'S AND THE
TRUSTEE'S RIGHTS PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER PURSUANT TO CLAUSES
(D), (E) OR (F) TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL, CERTIFICATION
AND/OR OTHER INFORMATION SATISFACTORY TO EACH OF THEM AND IN THE CASE OF THE
FOREGOING CLAUSE (E), A CERTIFICATE OF TRANSFER ( A FORM OF WHICH MAY BE
OBTAINED FROM THE ISSUER OR THE TRUSTEE) COMPLETED AND DELIVERED BY THE
TRANSFEROR TO THE ISSUER AND THE TRUSTEE. THIS LEGEND WILL BE

                                       2

<PAGE>   38

REMOVED AFTER 40 CONSECUTIVE DAYS BEGINNING ON AND INCLUDING THE LATER OF (A)
THE DAY ON WHICH THE SECURITIES ARE OFFERED TO PERSONS OTHER THAN DISTRIBUTORS
(AS DEFINED IN REGULATION S) AND (B) THE DATE OF THE CLOSING OF THE ORIGINAL
OFFERING. AS USED HEREIN, THE TERMS "OFFSHORE TRANSACTION", "UNITED STATES" AND
"U.S. PERSON" HAVE THE MEANINGS GIVEN TO THEM BY REGULATION S UNDER THE
SECURITIES ACT.]

                  UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED
REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY ("DTC") TO THE COMPANY OR ITS
AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE
ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER REPRESENTATIVE OF
DTC AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT
HEREON IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN
AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR
VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL SINCE THE REGISTERED OWNER
HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

                  TRANSFERS OF THIS GLOBAL BOND SHALL BE LIMITED TO TRANSFERS IN
WHOLE, BUT NOT IN PART, TO NOMINEES OF CEDE & CO. OR TO A SUCCESSOR THEREOF OR
SUCH SUCCESSOR'S NOMINEE AND TRANSFERS OF PORTIONS OF THIS GLOBAL BOND SHALL BE
LIMITED TO TRANSFERS MADE IN ACCORDANCE WITH THE RESTRICTIONS SET FORTH IN THE
INDENTURE.

                                       3

<PAGE>   39

No.                                                [CUSIP] [CINS] [ISIN] NUMBER
                                                               [    ]

Principal Amount        Final Scheduled Payment Date        Issue Date
----------------        ----------------------------        ----------
$[___________]                December 15, 2004             February 22, 2000

         REGISTERED HOLDER:         CEDE & CO.

         PRINCIPAL AMOUNT:          [_________________] Dollars

         INTEREST RATE:             8.065%

                  NRG NORTHEAST GENERATING LLC, a Delaware limited liability
company (hereinafter called the "Company", which term includes any successor or
assign under the Indenture referred to below), for value received hereby
promises to pay to Cede & Co., or its registered assigns, the outstanding
Principal Amount hereof after subtracting the aggregate principal amount of any
definitive Bonds issued in exchange for a portion or portions hereof, such
payment to be made in semiannual installments on June 15 and December 15 of each
year (commencing December 15, 2000) and ending on the final Scheduled Payment
Date set forth above, each such installment to be in the amount and payable on
the date set forth on Annex A attached hereto (provided that the portion of the
Principal Amount remaining unpaid on the final Scheduled Payment Date, together
with all interest accrued thereon, shall in any and all cases be due and payable
on the final Scheduled Payment Date), and to pay interest on the unpaid portion
of the Principal Amount at the interest rate set forth above (subject to the
fourteenth paragraph set forth on the reverse of this Bond, which refers to a
Registration Default) from the most recent Scheduled Payment Date to which
interest has been paid or duly provided for or, if no interest has been paid or
duly provided for, from the issue date set forth above, semiannually on June 15
and December 15 in each year (commencing June 15, 2000), until the Principal
Amount is paid in full or payment thereof is duly provided for. Any installment
of principal and, to the extent permitted by applicable law, any payment of
interest not punctually paid or duly provided for shall continue to bear
interest at a rate equal to the interest rate set forth above. The principal and
interest so payable, and punctually paid or duly provided for, at any Scheduled
Payment Date shall, as provided in the Indenture, be paid to the Person in whose
name this Bond (or one or more Predecessor Bonds) is registered in the Security
Register at the close of business on the Regular Record Date for such payment of
principal and interest, which shall be June 1 or December 1, as the case may be
(whether or not a Business Day), next preceding such Scheduled Payment Date. Any
such principal and interest that is payable, but is not so punctually paid or
duly provided for at any Scheduled Payment Date, shall forthwith cease to be
payable to the Holder hereof on such Regular Record Date, and may be paid to the
Person in whose name this Bond (or one or more Predecessor Bonds) is registered
at the close of business on a Special Record Date for the payment of such
defaulted principal and interest (together with any other amounts payable with
respect to such principal and interest), to be fixed by the Trustee, notice of
which shall be given to the Holder hereof not less than 10 days prior to such
Special Record

                                       4

<PAGE>   40

Date, or may be paid at any time in any other lawful manner not inconsistent
with the requirements of any securities exchange on which this Bond may be
listed, and upon such notice as may be required by such exchange, all as more
fully provided in the Indenture. This being a Global Bond (as that term is
defined in the Indenture) deposited with DTC acting as depository, and
registered in the name of Cede & Co. a nominee of DTC, Cede & Co., as holder of
record of this Bond shall be entitled to receive payment of principal and
interest, other than principal and interest due at the final Scheduled Payment
Date, by wire transfer of immediately available funds. Payment of the final
installment of principal payable with respect to this Bond shall be made as
provided in Section 8.5 of the Indenture (in the event this Bond is redeemed) or
shall be made upon presentation and surrender of this Bond at the Place of
Payment. All payments in respect of this Bond shall be made in such coin or
currency of the United States of America as at the time of payment is legal
tender for payment of debts.

                  Whenever any amount to be paid hereunder is stated to be due
on a day that is not a Business Day, such amount shall be payable on the next
succeeding Business Day and if such payment is timely made, no interest shall
accrue for the period from and after the day on which such payment was due.
Interest payments for this Bond will be computed and paid on the basis of a
360-day year consisting of twelve 30-day months.

                  Reference is made to the further provisions of this Bond set
forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if set forth at this place.

                  Unless the certificate of authentication hereon has been
executed by the Trustee by manual signature, this Bond shall not be entitled to
any benefit under the Indenture, or be valid or obligatory for any purpose.

                  IN WITNESS WHEREOF, the Company has caused this instrument to
be duly executed.

                                          NRG NORTHEAST GENERATING LLC

                                          By
                                            ------------------------------
                                           Name:
                                           Title:

                                       5

<PAGE>   41

                          CERTIFICATE OF AUTHENTICATION

                  This Bond is one of the Bonds referred to in the
within-mentioned Indenture.

THE CHASE MANHATTAN BANK,
  as Trustee

By:
   -------------------------
   Authorized Signatory

                                       6

<PAGE>   42

                       [Form of reverse of Global Bond for
                 8.065% Series A Senior Secured Bonds Due 2004]

                          NRG NORTHEAST GENERATING LLC
                  8.065% SERIES A SENIOR SECURED BOND DUE 2004

                  This bond is one of an authorized issue of Bonds of the
Company known as its 8.065% Series A Senior Secured Bonds Due 2004 (the
"Bonds"). The Bonds are issued under the Indenture dated as of February 22, 2000
(the "Original Indenture") among the Company, the Guarantors party thereto and
The Chase Manhattan Bank, a New York banking corporation, as trustee (in such
capacity, together with its successors in such capacity, the "Trustee"), as
supplemented by the First Supplemental Indenture dated as of February 22, 2000
(the "First Supplemental Indenture") among the Company, the Guarantors party
thereto and the Trustee (the Original Indenture, as so supplemented, and as the
same may be amended, modified and further supplemented, the "Indenture"). All
capitalized terms used herein, unless otherwise defined herein, shall have the
meanings ascribed to them in the Indenture.

                  All Bonds of any series issued and Outstanding under the
Indenture rank on a parity with each other Bond of the same series and with all
Bonds of each other series. Reference is hereby made to the Indenture for a
description of the nature and extent of the Bonds and the respective rights,
limitations of rights, duties and immunities thereunder of the Holders and of
the Trustee and the Company in respect of the Bonds and the terms upon which the
Bonds are made and are to be authenticated and delivered.

                  The principal of and interest on, this Bond are (i) guaranteed
by the Guarantors and (ii) secured by assets subject to the Lien of the
Collateral Documents, and all payments of principal and interest shall be made
in accordance with the terms of the Indenture. Each Holder, by acceptance of
this Bond, hereby acknowledges and agrees that (a) subject to the terms of
Section 10.2 of the Original Indenture, it will look solely to the assets of the
Company, the other Collateral purported to be covered under the Collateral
Documents and the income and proceeds received by the Trustee therefrom to the
extent available for distribution to such Holder as herein provided or provided
in the Collateral Documents, (b) none of the Members, or any of their respective
past, present or future members, officers, partners, directors or shareholders
or other Related Persons, or the Trustee shall be personally or otherwise liable
to any Holder, nor shall the Members, nor any of their respective past, present
or future members, officers, partners, directors or shareholders or other
Related Persons, be personally or otherwise liable to the Trustee for any
amounts payable under any Bond or for any liability under the Indenture or any
other Transaction Document, except as provided in the Original Indenture and (c)
recourse for any such amounts payable shall be otherwise limited in accordance
with Section 2.14 and Section 17.1 of the Original Indenture.

                  The obligations of the Company to pay the principal of and
interest on the Bonds when due as herein prescribed are absolute and
unconditional and no provision of this Bond or the Indenture shall alter or
impair such obligations.

                  The Bonds are subject to a Security Agreement dated as of
February 22, 2000 pursuant to which the rights of the Secured Parties (including
the Holders and the Trustee) in

                                       7

<PAGE>   43

respect of the Collateral will be shared among the Secured Parties and will be
exercised by the Collateral Agent in accordance with the Security Agreement.

                  The Indenture permits, with certain exceptions, as therein
provided, the amendment thereof and the modification of the rights and
obligations of the Company and the rights of the Holder under the Indenture at
any time by the Company with the consent of the Holders of not less than a
majority in aggregate principal amount of the Bonds of all series then
Outstanding. The Indenture also contains provisions permitting the Holders of
specified percentages in aggregate principal amount of the Bonds of all series
then Outstanding, on behalf of the Holders of all the Bonds, to waive compliance
by the Company with certain provisions of the Indenture and certain past
defaults under the Indenture and their consequences. Any Act (as such term is
defined in the Indenture), including, but not limited to, such a consent, waiver
or direction by the Holder of this Bond shall be conclusive and binding upon the
Holder and upon all future Holders of this Bond and the Holder of every Bond
issued upon the transfer hereof or the exchange herefor or in lieu hereof
whether or not notation of such Act is made upon this Bond.

                  This Bond is one of the series designated on the face hereof,
limited to $320,000,000 in aggregate principal amount as provided in the First
Supplemental Indenture.

                  This Bond and all Bonds issued or to be issued in series
created under the First Supplemental Indenture are (i) redeemable at the option
of the Company in accordance with Section 8.2 of the Indenture, on not less than
30 nor more than 60 days' notice, at a redemption price equal to the principal
amount thereof plus unpaid and accrued interest plus the Make-Whole Premium and
(ii) not subject to any sinking fund.

                  The Bonds are, under certain conditions, subject to mandatory
redemption as set forth in Section 8.3 of the Indenture. Notice of any
redemption of Bonds will be given at least 30 days but not more than 60 days
before the Redemption Date to each Holder at its address as it appears in the
Security Register.

                  Bonds (or portions thereof as aforesaid) for the redemption of
which provision is made in accordance with the Indenture shall cease to bear
interest from and after any Redemption Date.

                  The Indenture contains provisions for, upon compliance by the
Company with certain conditions set forth in the Indenture, the defeasance of
(a) the entire indebtedness of this Bond and (b) certain restrictive covenants
and agreements.

                  The unpaid portion of the Principal Amount, together with any
interest accrued and unpaid thereon and all other amounts due hereunder, if any,
may become due and payable upon the occurrence and continuation of any Event of
Default, but only as provided in the Indenture.

                  The Company and the Guarantors have entered into an Exchange
and Registration Rights Agreement dated February 15, 2000 (the "Registration
Rights Agreement") with the Initial Purchasers described therein. Pursuant to
such Registration Rights Agreement, the Company and the Guarantors have agreed
to file with the SEC a registration statement under the

                                       8

<PAGE>   44

Securities Act ("Registration Statement") for an offer to exchange the Bonds for
a like aggregate principal amount of Bonds issued pursuant to the Indenture that
are in all material respects identical to the Bonds except that such exchange
Bonds shall be issued pursuant to an effective Registration Statement.

                  From and after the date on which a Registration Default (as
defined in the Registration Rights Agreement) occurs, the interest rate payable
on this Bond shall increase (in addition to the interest rate set forth above)
and additional interest reflecting such increase shall accrue with respect to
this Bond, until but not including the date on which such Registration Default
shall cease to exist (and provided no other Registration Default with respect to
this Bond shall then be continuing), at the rate of one half of one percent
(0.50%) per annum, which additional interest shall be payable hereon at the
times, in the manner and subject to the same terms and conditions set forth
herein and in the Indenture, as though the interest rate set forth above had
been increased by one half of one percent (0.50%) per annum.

                  The Bonds are issuable only as registered Bonds without
coupons in minimum denominations of $100,000 and any integral multiple of $1,000
in excess thereof. As provided in, and subject to the provisions of, the
Indenture, Bonds are exchangeable at the option of the Holder thereof for other
Bonds of the same series, of authorized denomination and of like tenor,
maturity, interest rate and aggregate principal amount, to be registered in the
name of such Holder, upon surrender thereof by such Holder at any office or
agency maintained for such purpose pursuant to the Indenture.

                  No service charge will be required of any Holder participating
in any such transfer or exchange of Bonds in respect of such transfer or
exchange, but the Security Registrar may require payment of a sum sufficient to
cover any tax or other governmental charge payable in connection therewith.

                  The person in whose name this Bond is registered shall be
deemed to be the owner and holder hereof for the purpose of receiving payment as
herein provided and for all other purposes whether or not this Bond be overdue
regardless of any notice to anyone to the contrary.

                  Bonds actually known to a Responsible Officer of the Trustee
to be owned or held by, or for the account or benefit of, the Company, the
Guarantors, or an Affiliate of any of the foregoing shall not be entitled to
share in any payment or distribution provided for in Article 10 of the Indenture
until all Bonds held by other Persons have been indefeasibly paid in full.

                  THIS BOND SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE
WITH, THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO PRINCIPLES OF
CONFLICTS OF LAW THEREOF TO THE EXTENT THE APPLICATION OF SUCH PRINCIPLES WOULD
CAUSE THE APPLICATION OF THE LAWS OF ANY OTHER JURISDICTION.

                                       9

<PAGE>   45

                                  ABBREVIATIONS

                  The following abbreviations when used in the inscription on
the face of this instrument shall be construed as though they were written out
in full according to applicable laws or regulations:

         TEN COM  --       as tenants in common
         TEN ENT  --       as tenants by the entireties
          JT TEN  --       as joint tenants with right of
                           survivorship and not as tenants in
                           common

                      UNIF GIFT MIN ACT
                                           ------------------------------------
                                                     (Cust)   (Minor)

                                           under Uniform Gift to Minors Act

                                           ------------------------------------
                                                         (State)

                Additional abbreviations may also be used though
                              not in the above list

                               -------------------

                                       10

<PAGE>   46

                  FOR VALUE-RECEIVED the undersigned hereby sell(s),
assign(s) and transfer(s) unto

Social Security Number or Other
Identifying Number of Assignee
                               -------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
                  (Please print or typewrite name and address,
                         including zip code of Assignee)

the within Security and all rights thereunder, hereby irrevocably constituting
and appointing _______ attorney to transfer said Security on the books of the
Company, with full power of substitution in the premises.

Dated:
      ---------------------------

                                                ------------------------------
                                                NAME:

NOTICE: The signature to this assignment must correspond with the name as
        written upon the first page of the within instrument in every
        particular, without alteration or enlargement or any change whatsoever.

                                       11

<PAGE>   47

                                                                      ANNEX A TO
                                    8.065% SERIES A SENIOR SECURED BOND DUE 2004

                  The following table sets forth the date of each semiannual
installment of the aggregate principal to be paid on all Bonds of this series on
each such date:

<TABLE>
<CAPTION>
                                                                                        PRINCIPAL
                                                                                           AMOUNT
                           PRINCIPAL                                                      PAYABLE
                             PAYMENT                                                    ON SERIES
                               DATES                                                      A BONDS
                               -----                                                      -------
<S>                                                                               <C>
                   December 15, 2000                                                  $50,000,000
                       June 15, 2001                                                   45,000,000
                   December 15, 2001                                                   45,000,000
                       June 15, 2002                                                   53,500,000
                   December 15, 2002                                                   53,500,000
                       June 15, 2003                                                   17,500,000
                   December 15, 2003                                                   17,500,000
                       June 15, 2004                                                   19,000,000
                   December 15, 2004                                                   19,000,000
                               TOTAL                                                 $320,000,000

</TABLE>

                                       12

<PAGE>   48

                                                                      ANNEX B TO
                                    8.065% SERIES A SENIOR SECURED BOND DUE 2004

         Exchanges of portions of this Global Bond for definitive Bonds:

<TABLE>
<CAPTION>
==========================================================================================================
                         PRINCIPAL AMOUNT OF
                         DEFINITIVE SECURITIES ISSUED       REMAINING PRINCIPAL            NOTATION MADE
                         IN EXCHANGE FOR A PORTION          AMOUNT OF THIS GLOBAL          BY
DATE                     OF THIS GLOBAL SECURITY            SECURITY

<S>                     <C>                                <C>                            <C>
----------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------

==========================================================================================================
</TABLE>

                                       13

<PAGE>   49

                                                           Schedule 2-A to First
                                                       Supplemental Indenture to
                                              NRG Northeast Generating Indenture

                           [Form of face of definitive
                 8.842% Series B Senior Secured Bonds Due 2010]

                          NRG NORTHEAST GENERATING LLC
                  8.842% SERIES B SENIOR SECURED BOND DUE 2010

                  THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT
OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR THE SECURITIES LAWS OF ANY STATE
OR OTHER JURISDICTION. NEITHER THIS SECURITY NOR ANY INTEREST OR PARTICIPATION
HEREIN MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR
OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH
TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, SUCH REGISTRATION.

                  THE HOLDER OF THIS SECURITY BY ITS ACCEPTANCE HEREOF AGREES TO
OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE "RESALE
RESTRICTION TERMINATION DATE") WHICH IS TWO YEARS AFTER THE LATER OF THE
ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH THE ISSUER OR ANY
AFFILIATE OF THE ISSUER WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF
SUCH SECURITY), ONLY (A) TO THE ISSUER, (B) PURSUANT TO A REGISTRATION STATEMENT
THAT HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT, (C) FOR SO LONG AS
THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THE
SECURITIES ACT ("RULE 144A"), TO A PERSON IT REASONABLY BELIEVES IS A "QUALIFIED
INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A THAT PURCHASES FOR ITS OWN ACCOUNT
OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN
THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (D) PURSUANT TO OFFERS
AND SALES THAT OCCUR OUTSIDE THE UNITED STATES WITHIN THE MEANING OF REGULATION
S UNDER THE SECURITIES ACT, (E) TO AN INSTITUTIONAL "ACCREDITED INVESTOR" WITHIN
THE MEANING OF RULE 501(a)(1), (2), (3) OR (7) UNDER THE SECURITIES ACT THAT IS
AN INSTITUTIONAL INVESTOR ACQUIRING THE SECURITY FOR ITS OWN ACCOUNT OR FOR THE
ACCOUNT OF SUCH AN INSTITUTIONAL ACCREDITED INVESTOR, IN EACH CASE IN A MINIMUM
PRINCIPAL AMOUNT OF THE SECURITIES OF $250,000, FOR INVESTMENT PURPOSES AND NOT
WITH A VIEW TO OR FOR OFFER OR SALE IN CONNECTION WITH ANY DISTRIBUTION IN
VIOLATION OF THE SECURITIES ACT OR (F) PURSUANT TO ANY OTHER AVAILABLE EXEMPTION
FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE
ISSUER'S AND THE TRUSTEE'S RIGHTS PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER
PURSUANT TO CLAUSES (D), (E) OR (F) TO REQUIRE THE DELIVERY OF AN OPINION OF

<PAGE>   50

COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO EACH OF THEM AND
IN THE CASE OF THE FOREGOING CLAUSE (E), A CERTIFICATE OF TRANSFER (A FORM OF
WHICH MAY BE OBTAINED FROM THE ISSUER OR THE TRUSTEE) COMPLETED AND DELIVERED BY
THE TRANSFEROR TO THE ISSUER AND THE TRUSTEE. THIS LEGEND WILL BE REMOVED UPON
THE REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE.

                                       2

<PAGE>   51

No.                                                                CUSIP NUMBER
                                                                      [    ]

Principal Amount         Final Scheduled Payment Date        Issue Date
----------------         ----------------------------        ----------
$[___________]                   June 15, 2015               February 22, 2000

         REGISTERED HOLDER:         [_______________]

         PRINCIPAL AMOUNT:          [_______________] Dollars

         INTEREST RATE:             8.842%

                  NRG NORTHEAST GENERATING LLC, a Delaware limited liability
company (hereinafter called the "Company", which term includes any successor or
assign under the Indenture referred to below), for value received hereby
promises to pay to [____________], or its registered assigns, the outstanding
Principal Amount hereof, such payment to be made in semiannual installments on
June 15 and December 15 of each year (commencing June 15, 2007) and ending on
the final Scheduled Payment Date set forth above, each such installment to be in
the amount and payable on the date set forth on Annex A attached hereto
(provided that the portion of the Principal Amount remaining unpaid on the final
Scheduled Payment Date, together with all interest accrued thereon, shall in any
and all cases be due and payable on the final Scheduled Payment Date), and to
pay interest on the unpaid portion of the Principal Amount at the interest rate
set forth above (subject to the fourteenth paragraph set forth on the reverse of
this Bond, which refers to a Registration Default) from the most recent
Scheduled Payment Date to which interest has been paid or duly provided for or,
if no interest has been paid or duly provided for, from the issue date set forth
above, semiannually on June 15 and December 15 in each year (commencing June 15,
2000) until the Principal Amount is paid in full or payment thereof is duly
provided for. Any installment of principal and, to the extent permitted by
applicable law, any payment of interest not punctually paid or duly provided for
shall continue to bear interest at a rate equal to the interest rate set forth
above. The principal and interest so payable, and punctually paid or duly
provided for, at any Scheduled Payment Date shall, as provided in the Indenture,
be paid to the Person in whose name this Bond (or one or more Predecessor Bonds)
is registered in the Security Register at the close of business on the Regular
Record Date for such payment of principal and interest, which shall be June 1 or
December 1, as the case may be (whether or not a Business Day), next preceding
such Scheduled Payment Date. Any such principal and interest that is payable,
but is not so punctually paid or duly provided for at any Scheduled Payment
Date, shall forthwith cease to be payable to the Holder hereof on such Regular
Record Date, and may be paid to the Person in whose name this Bond (or one or
more Predecessor Bonds) is registered at the close of business on a Special
Record Date for the payment of such defaulted principal and interest (together
with any other amounts payable with respect to such principal and interest), to
be fixed by the Trustee, notice of which shall be given to the Holder hereof not
less than 10 days prior to such Special Record Date, or may be paid at any time
in any other lawful manner not inconsistent with the requirements of any
securities exchange on which this Bond may be listed, and upon such notice as
may be required by such

                                       3

<PAGE>   52

exchange, all as more fully provided in the Indenture. Payments of principal of
and interest on this Bond shall be made (i) if the Company so elects, by check
mailed to the Holder at his or her registered address or (ii) otherwise, at the
Place of Payment; provided, that the final installment of principal payable with
respect to this Bond shall be made as provided in Section 8.5 of the Indenture
(in the event this Bond is redeemed) or shall be made upon presentation and
surrender of this Bond at the Place of Payment. All payments in respect of this
Bond shall be made in such coin or currency of the United States of America as
at the time of payment is legal tender for payment of debts.

                  Whenever any amount to be paid hereunder is stated to be due
on a day that is not a Business Day, such amount shall be payable on the next
succeeding Business Day and if such payment is timely made, no interest shall
accrue for the period from and after the day on which such payment was due.
Interest payments for this Bond will be computed and paid on the basis of a
360-day year consisting of twelve 30-day months.

                  Reference is made to the further provisions of this Bond set
forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if set forth at this place.

                  Unless the certificate of authentication hereon has been
executed by the Trustee by manual signature, this Bond shall not be entitled to
any benefit under the Indenture, or be valid or obligatory for any purpose.

                  IN WITNESS WHEREOF, the Company has caused this instrument to
be duly executed.

                                        NRG NORTHEAST GENERATING LLC

                                        By
                                          -----------------------------
                                         Name:
                                         Title:

                                       4

<PAGE>   53

                          CERTIFICATE OF AUTHENTICATION

                  This Bond is one of the Bonds referred to in the
within-mentioned Indenture.

THE CHASE MANHATTAN BANK,
   as Trustee

By:
   --------------------------
   Authorized Signatory

                                       5
<PAGE>   54
                        [Form of reverse of definitive
                 8.842% Series B Senior Secured Bonds Due 2015]

                          NRG NORTHEAST GENERATING LLC
                  8.842% SERIES B SENIOR SECURED BOND DUE 2015

                  This bond is one of an authorized issue of Bonds of the
Company known as its 8.842% Series B Senior Secured Bonds Due 2010 (the
"Bonds"). The Bonds are issued under the Indenture dated as of February 22, 2000
(the "Original Indenture") among the Company, the Guarantors party thereto and
The Chase Manhattan Bank, a New York banking corporation, as trustee (in such
capacity, together with its successors in such capacity, the "Trustee"), as
supplemented by the First Supplemental Indenture dated as of February 22, 2000
(the "First Supplemental Indenture") among the Company, the Guarantors party
thereto and the Trustee (the Original Indenture, as so supplemented, and as the
same may be amended, modified and further supplemented, the "Indenture"). All
capitalized terms used herein, unless otherwise defined herein, shall have the
meanings ascribed to them in the Indenture.

                  All Bonds of any series issued and Outstanding under the
Indenture rank on a parity with each other Bond of the same series and with all
Bonds of each other series. Reference is hereby made to the Indenture for a
description of the nature and extent of the Bonds and the respective rights,
limitations of rights, duties and immunities thereunder of the Holders and of
the Trustee and the Company in respect of the Bonds and the terms upon which the
Bonds are made and are to be authenticated and delivered.

                  The principal of and interest on, this Bond are (i) guaranteed
by the Guarantors and (ii) secured by assets subject to the Lien of the
Collateral Documents, and all payments of principal and interest shall be made
in accordance with the terms of the Indenture. Each Holder, by acceptance of
this Bond, hereby acknowledges and agrees that (a) subject to the terms of
Section 10.2 of the Original Indenture, it will look solely to the assets of the
Company, the other Collateral purported to be covered under the Collateral
Documents and the income and proceeds received by the Trustee therefrom to the
extent available for distribution to such Holder as herein provided or provided
in the Collateral Documents, (b) none of the Members, or any of their respective
past, present or future members, officers, partners, directors or shareholders
or other Related Persons, or the Trustee shall be personally or otherwise liable
to any Holder, nor shall the Members, nor any of their respective past, present
or future members, officers, partners, directors or shareholders or other
Related Persons, be personally or otherwise liable to the Trustee for any
amounts payable under any Bond or for any liability under the Indenture or any
other Transaction Document, except as provided in the Original Indenture and (c)
recourse for any such amounts payable shall be otherwise limited in accordance
with Section 2.14 and Section 17.1 of the Original Indenture.

                  The obligations of the Company to pay the principal of and
interest on the Bonds when due as herein prescribed are absolute and
unconditional and no provision of this Bond or the Indenture shall alter or
impair such obligations.

                  The Bonds are subject to a Security Agreement dated as of
February 22, 2000 pursuant to which the rights of the Secured Parties (including
the Holders and the Trustee) in
                                       6

<PAGE>   55

respect of the Collateral will be shared among the Secured Parties and will be
exercised by the Collateral Agent in accordance with the Security Agreement.

                  The Indenture permits, with certain exceptions, as therein
provided, the amendment thereof and the modification of the rights and
obligations of the Company and the rights of the Holder under the Indenture at
any time by the Company with the consent of the Holders of not less than a
majority in aggregate principal amount of the Bonds of all series then
Outstanding. The Indenture also contains provisions permitting the Holders of
specified percentages in aggregate principal amount of the Bonds of all series
then Outstanding, on behalf of the Holders of all the Bonds, to waive compliance
by the Company with certain provisions of the Indenture and certain past
defaults under the Indenture and their consequences. Any Act (as such term is
defined in the Indenture), including, but not limited to, such a consent, waiver
or direction by the Holder of this Bond shall be conclusive and binding upon the
Holder and upon all future Holders of this Bond and the Holder of every Bond
issued upon the transfer hereof or the exchange herefor or in lieu hereof
whether or not notation of such Act is made upon this Bond.

                  This Bond is one of the series designated on the face hereof,
limited to $130,000,000 in aggregate principal amount as provided in the First
Supplemental Indenture.

                  This Bond and all Bonds issued or to be issued in series
created under the First Supplemental Indenture are (i) redeemable at the option
of the Company in accordance with Section 8.2 of the Indenture, on not less than
30 nor more than 60 days' notice, at a redemption price equal to the principal
amount thereof plus unpaid and accrued interest plus the Make-Whole Premium and
(ii) not subject to any sinking fund.

                  The Bonds are, under certain conditions, subject to mandatory
redemption as set forth in Section 8.3 of the Indenture. Notice of any
redemption of Bonds will be given at least 30 days but not more than 60 days
before the Redemption Date to each Holder at its address as it appears in the
Security Register.

                  Bonds (or portions thereof as aforesaid) for the redemption of
which provision is made in accordance with the Indenture shall cease to bear
interest from and after any Redemption Date.

                  The Indenture contains provisions for, upon compliance by the
Company with certain conditions set forth in the Indenture, the defeasance of
(a) the entire indebtedness of this Bond and (b) certain restrictive covenants
and agreements.

                  The unpaid portion of the Principal Amount, together with any
interest accrued and unpaid thereon and all other amounts due hereunder, if any,
may become due and payable upon the occurrence and continuation of any Event of
Default, but only as provided in the Indenture.

                  The Company and the Guarantors have entered into an Exchange
and Registration Rights Agreement dated February 15, 2000 (the "Registration
Rights Agreement") with the Initial Purchasers described therein. Pursuant to
such Registration Rights Agreement, the Company and the Guarantors have agreed
to file with the SEC a registration statement under the

                                       7
<PAGE>   56

Securities Act ("Registration Statement") for an offer to exchange the Bonds for
a like aggregate principal amount of Bonds issued pursuant to the Indenture that
are in all material respects identical to the Bonds except that such exchange
Bonds shall be issued pursuant to an effective Registration Statement.

                  From and after the date on which a Registration Default (as
defined in the Registration Rights Agreement) occurs, the interest rate payable
on this Bond shall increase (in addition to the interest rate set forth above)
and additional interest reflecting such increase shall accrue with respect to
this Bond, until but not including the date on which such Registration Default
shall cease to exist (and provided no other Registration Default with respect to
this Bond shall then be continuing), at the rate of one half of one percent
(0.50%) per annum, which additional interest shall be payable hereon at the
times, in the manner and subject to the same terms and conditions set forth
herein and in the Indenture, as though the interest rate set forth above had
been increased by one half of one percent (0.50%) per annum.

                  The Bonds are issuable only as registered Bonds without
coupons in minimum denominations of $100,000 and any integral multiple of $1,000
in excess thereof. As provided in, and subject to the provisions of, the
Indenture, Bonds are exchangeable at the option of the Holder thereof for other
Bonds of the same series, of authorized denomination and of like tenor,
maturity, interest rate and aggregate principal amount, to be registered in the
name of such Holder, upon surrender thereof by such Holder at any office or
agency maintained for such purpose pursuant to the Indenture.

                  No service charge will be required of any Holder participating
in any such transfer or exchange of Bonds in respect of such transfer or
exchange, but the Security Registrar may require payment of a sum sufficient to
cover any tax or other governmental charge payable in connection therewith.

                  The person in whose name this Bond is registered shall be
deemed to be the owner and holder hereof for the purpose of receiving payment as
herein provided and for all other purposes whether or not this Bond be overdue
regardless of any notice to anyone to the contrary.

                  Bonds actually known to a Responsible Officer of the Trustee
to be owned or held by, or for the account or benefit of, the Company, the
Guarantors, or an Affiliate of any of the foregoing shall not be entitled to
share in any payment or distribution provided for in Article 10 of the Indenture
until all Bonds held by other Persons have been indefeasibly paid in full.

                  THIS BOND SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE
WITH, THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO PRINCIPLES OF
CONFLICTS OF LAW THEREOF TO THE EXTENT THE APPLICATION OF SUCH PRINCIPLES WOULD
CAUSE THE APPLICATION OF THE LAWS OF ANY OTHER JURISDICTION.

                                       8

<PAGE>   57

                                                                      ANNEX A TO
                                    8.842% SERIES B SENIOR SECURED BOND DUE 2015

                  The following table sets forth the date of each semiannual
installment of the aggregate principal to be paid on all Bonds of this series on
each such date:

                                                                      PRINCIPAL
                                                                         AMOUNT
                           PRINCIPAL                                    PAYABLE
                             PAYMENT                                  ON SERIES
                               DATES                                    B BONDS
                               -----                                    -------
                       June 15, 2007                                $16,500,000
                   December 15, 2007                                 16,500,000
                       June 15, 2008                                 17,000,000
                   December 15, 2008                                 17,000,000
                       June 15, 2009                                 19,000,000
                   December 15, 2009                                 19,000,000
                       June 15, 2010                                  2,000,000
                   December 15, 2010                                  2,000,000
                       June 15, 2011                                  2,000,000
                   December 15, 2011                                  2,000,000
                       June 15, 2012                                  2,000,000
                   December 15, 2012                                  2,000,000
                       June 15, 2013                                  2,500,000
                   December 15, 2013                                  2,500,000
                       June 15, 2014                                  2,500,000
                   December 15, 2014                                  2,500,000
                       June 15, 2015                                  3,000,000
                               TOTAL                               $130,000,000

                                       9

<PAGE>   58

                                  ABBREVIATIONS

                  The following abbreviations when used in the inscription on
the face of this instrument shall be construed as though they were written out
in full according to applicable laws or regulations:

         TEN COM  --       as tenants in common
         TEN ENT  --       as tenants by the entireties
          JT TEN  --       as joint tenants with right of
                           survivorship and not as tenants in
                           common

                      UNIF GIFT MIN ACT
                                          -------------------------------------
                                                   (Cust)   (Minor)

                                          under Uniform Gift to Minors Act

                                          -------------------------------------
                                                        (State)

                Additional abbreviations may also be used though
                              not in the above list

                               -------------------

                                       10
<PAGE>   59

                  FOR VALUE-RECEIVED the undersigned hereby sell(s),
assign(s) and transfer(s) unto

Identifying Number of Assignee
                              -------------------------------------------------

-------------------------------------------------------------------------------

-------------------------------------------------------------------------------

-------------------------------------------------------------------------------
                  (Please print or typewrite name and address,
                         including zip code of Assignee)

the within Bond and all rights thereunder, hereby irrevocably constituting and
appointing________  attorney to transfer said Bond on the books of the Company,
with full power of substitution in the premises.

Dated:
      ---------------------

                                                              ------------------
                                                              NAME:

NOTICE:           The signature to this assignment must correspond with the name
                  as written upon the first page of the within instrument in
                  every particular, without alteration or enlargement or any
                  change whatsoever.

                                       11
<PAGE>   60

                                                           Schedule 2-B to First
                                                          Supplemental Indenture

                          [Form of face of Global Bond
               for 8.842% Series B Senior Secured Bonds Due 2010]

                          NRG NORTHEAST GENERATING LLC
                  8.842% SERIES B SENIOR SECURED BOND DUE 2010

                  [Insert in Rule 144A Global Bonds -- THIS SECURITY HAS NOT
BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES
ACT"), OR THE SECURITIES LAWS OF ANY STATE OR OTHER JURISDICTION. NEITHER THIS
SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN MAY BE REOFFERED, SOLD,
ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE
ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT
SUBJECT TO, SUCH REGISTRATION.

                  THE HOLDER OF THIS SECURITY BY ITS ACCEPTANCE HEREOF AGREES TO
OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE "RESALE
RESTRICTION TERMINATION DATE") WHICH IS TWO YEARS AFTER THE LATER OF THE
ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH THE ISSUER OR ANY
AFFILIATE OF THE ISSUER WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF
SUCH SECURITY), ONLY (A) TO THE ISSUER, (B) PURSUANT TO A REGISTRATION STATEMENT
THAT HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT, (C) FOR SO LONG AS
THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THE
SECURITIES ACT ("RULE 144A"), TO A PERSON IT REASONABLY BELIEVES IS A "QUALIFIED
INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A THAT PURCHASES FOR ITS OWN ACCOUNT
OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN
THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (D) PURSUANT TO OFFERS
AND SALES THAT OCCUR OUTSIDE THE UNITED STATES WITHIN THE MEANING OF REGULATION
S UNDER THE SECURITIES ACT, (E) TO AN INSTITUTIONAL "ACCREDITED INVESTOR" WITHIN
THE MEANING OF RULE 501(a)(1), (2), (3) OR (7) UNDER THE SECURITIES ACT THAT IS
AN INSTITUTIONAL INVESTOR ACQUIRING THE SECURITY FOR ITS OWN ACCOUNT OR FOR THE
ACCOUNT OF SUCH AN INSTITUTIONAL ACCREDITED INVESTOR, IN EACH CASE IN A MINIMUM
PRINCIPAL AMOUNT OF THE SECURITIES OF $250,000, FOR INVESTMENT PURPOSES AND NOT
WITH A VIEW TO OR FOR OFFER OR SALE IN CONNECTION WITH ANY DISTRIBUTION IN
VIOLATION OF THE SECURITIES ACT OR (F) PURSUANT TO ANOTHER AVAILABLE EXEMPTION
FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE
ISSUER'S AND THE TRUSTEE'S RIGHTS PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER
PURSUANT TO CLAUSES (D), (E) OR (F) TO REQUIRE THE DELIVERY OF AN OPINION OF
COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO

<PAGE>   61

EACH OF THEM AND IN THE CASE OF THE FOREGOING CLAUSE (E), A CERTIFICATE OF
TRANSFER ( A FORM OF WHICH MAY BE OBTAINED FROM THE ISSUER OR THE TRUSTEE)
COMPLETED AND DELIVERED BY THE TRANSFEROR TO THE ISSUER AND THE TRUSTEE. THIS
LEGEND WILL BE REMOVED UPON THE REQUEST OF THE HOLDER AFTER THE RESALE
RESTRICTION TERMINATION DATE. ]

                  [Insert in Regulation S Global Bonds -- THIS SECURITY HAS NOT
BEEN REGISTERED UNDER THE UNITED STATES SECURITIES ACT OF 1933, AS AMENDED (THE
"SECURITIES ACT"), AND ACCORDINGLY, MAY NOT BE OFFERED OR SOLD WITHIN THE UNITED
STATES OR TO OR FOR THE ACCOUNT OR BENEFIT OF, U.S. PERSONS EXCEPT AS SET FORTH
IN THE FOLLOWING SENTENCE. BY ITS ACQUISITION HEREOF, THE HOLDER (1) REPRESENTS
THAT IT IS NOT A U.S. PERSON AND IS ACQUIRING THIS SECURITY IN AN OFFSHORE
TRANSACTION, (2) BY ITS ACCEPTANCE HEREOF AGREES TO OFFER, SELL OR OTHERWISE
TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE "RESALE RESTRICTION TERMINATION
DATE") WHICH IS TWO YEARS AFTER THE LATER OF THE ORIGINAL ISSUE DATE HEREOF AND
THE LAST DATE ON WHICH THE ISSUER OR ANY AFFILIATE OF THE ISSUER WAS THE OWNER
OF THIS SECURITY (OR ANY PREDECESSOR OF SUCH SECURITY), ONLY (A) TO THE ISSUER,
(B) PURSUANT TO A REGISTRATION STATEMENT THAT HAS BEEN DECLARED EFFECTIVE UNDER
THE SECURITIES ACT, (C) FOR SO LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE
PURSUANT TO RULE 144A UNDER THE SECURITIES ACT ("RULE 144A"), TO A PERSON IT
REASONABLY BELIEVES IS A "QUALIFIED INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A
THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED
INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN
RELIANCE ON RULE 144A, (D) PURSUANT TO OFFERS AND SALES THAT OCCUR OUTSIDE THE
UNITED STATES WITHIN THE MEANING OF REGULATION S UNDER THE SECURITIES ACT, (E)
TO AN INSTITUTIONAL "ACCREDITED INVESTOR" WITHIN THE MEANING OF RULE 501(a)(1),
(2), (3) OR (7) UNDER THE SECURITIES ACT THAT IS AN INSTITUTIONAL INVESTOR
ACQUIRING THE SECURITY FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF SUCH AN
INSTITUTIONAL ACCREDITED INVESTOR, IN EACH CASE IN A MINIMUM PRINCIPAL AMOUNT OF
THE SECURITIES OF $250,000, FOR INVESTMENT PURPOSES AND NOT WITH A VIEW TO OR
FOR OFFER OR SALE IN CONNECTION WITH ANY DISTRIBUTION IN VIOLATION OF THE
SECURITIES ACT OR (F) PURSUANT TO ANOTHER AVAILABLE EXEMPTION FROM THE
REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE ISSUER'S AND THE
TRUSTEE'S RIGHTS PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER PURSUANT TO CLAUSES
(D), (E) OR (F) TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL, CERTIFICATION
AND/OR OTHER INFORMATION SATISFACTORY TO EACH OF THEM AND IN THE CASE OF THE
FOREGOING CLAUSE (E), A CERTIFICATE OF TRANSFER ( A FORM OF WHICH MAY BE
OBTAINED FROM THE ISSUER OR THE TRUSTEE) COMPLETED AND DELIVERED BY THE
TRANSFEROR TO THE ISSUER AND THE TRUSTEE. THIS LEGEND WILL BE REMOVED AFTER 40
CONSECUTIVE DAYS BEGINNING ON AND INCLUDING THE LATER OF (A) THE DAY ON WHICH
THE SECURITIES ARE OFFERED TO PERSONS
                                       2
<PAGE>   62

OTHER THAN DISTRIBUTORS (AS DEFINED IN REGULATION S) AND (B) THE DATE OF THE
CLOSING OF THE ORIGINAL OFFERING. AS USED HEREIN, THE TERMS "OFFSHORE
TRANSACTION", "UNITED STATES" AND "U.S. PERSON" HAVE THE MEANINGS GIVEN TO THEM
BY REGULATION S UNDER THE SECURITIES ACT.]

                  UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED
REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY ("DTC") TO THE COMPANY OR ITS
AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE
ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER REPRESENTATIVE OF
DTC AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT
HEREON IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN
AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR
VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL SINCE THE REGISTERED OWNER
HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

                  TRANSFERS OF THIS GLOBAL BOND SHALL BE LIMITED TO TRANSFERS IN
WHOLE, BUT NOT IN PART, TO NOMINEES OF CEDE & CO. OR TO A SUCCESSOR THEREOF OR
SUCH SUCCESSOR'S NOMINEE AND TRANSFERS OF PORTIONS OF THIS GLOBAL BOND SHALL BE
LIMITED TO TRANSFERS MADE IN ACCORDANCE WITH THE RESTRICTIONS SET FORTH IN THE
INDENTURE.

                                       3
<PAGE>   63

No.                                                 [CUSIP] [CINS] [ISIN] NUMBER
                                                                [    ]

<TABLE>
<CAPTION>

<S>                                 <C>                                            <C>
Principal Amount                          Final Scheduled Payment Date              Issue Date
----------------                          ----------------------------              ----------

$[___________]                                    June 15, 2015                     February 22, 2000

         REGISTERED HOLDER:                 CEDE & CO.

         PRINCIPAL AMOUNT:          [_________________] Dollars

         INTEREST RATE:                     8.842%

</TABLE>

                  NRG NORTHEAST GENERATING LLC, a Delaware limited liability
company (hereinafter called the "Company", which term includes any successor or
assign under the Indenture referred to below), for value received hereby
promises to pay to Cede & Co., or its registered assigns, the outstanding
Principal Amount hereof after subtracting the aggregate principal amount of any
definitive Bonds issued in exchange for a portion or portions hereof, such
payment to be made in semiannual installments on June 15 and December 15 of each
year (commencing June 15, 2007) and ending on the final Scheduled Payment Date
set forth above, each such installment to be in the amount and payable on the
date set forth on Annex A attached hereto (provided that the portion of the
Principal Amount remaining unpaid on the final Scheduled Payment Date, together
with all interest accrued thereon, shall in any and all cases be due and payable
on the final Scheduled Payment Date), and to pay interest on the unpaid portion
of the Principal Amount at the interest rate set forth above (subject to the
fourteenth paragraph set forth on the reverse of this Bond, which refers to a
Registration Default) from the most recent Scheduled Payment Date to which
interest has been paid or duly provided for or, if no interest has been paid or
duly provided for, from the issue date set forth above, semiannually on June 15
and December 15 in each year (commencing June 15, 2000), until the Principal
Amount is paid in full or payment thereof is duly provided for. Any installment
of principal and, to the extent permitted by applicable law, any payment of
interest not punctually paid or duly provided for shall continue to bear
interest at a rate equal to the interest rate set forth above. The principal and
interest so payable, and punctually paid or duly provided for, at any Scheduled
Payment Date shall, as provided in the Indenture, be paid to the Person in whose
name this Bond (or one or more Predecessor Bonds) is registered in the Security
Register at the close of business on the Regular Record Date for such payment of
principal and interest, which shall be June 1 or December 1, as the case may be
(whether or not a Business Day), next preceding such Scheduled Payment Date. Any
such principal and interest that is payable, but is not so punctually paid or
duly provided for at any Scheduled Payment Date, shall forthwith cease to be
payable to the Holder hereof on such Regular Record Date, and may be paid to the
Person in whose name this Bond (or one or more Predecessor Bonds) is registered
at the close of business on a Special Record Date for the payment of such
defaulted principal and interest (together with any other amounts payable with
respect to such principal and interest), to be fixed by the Trustee, notice of
which shall be given to the Holder hereof not less than 10 days prior to such
Special Record
                                       4
<PAGE>   64

Date, or may be paid at any time in any other lawful manner not inconsistent
with the requirements of any securities exchange on which this Bond may be
listed, and upon such notice as may be required by such exchange, all as more
fully provided in the Indenture. This being a Global Bond (as that term is
defined in the Indenture) deposited with DTC acting as depository, and
registered in the name of Cede & Co. a nominee of DTC, Cede & Co., as holder of
record of this Bond shall be entitled to receive payment of principal and
interest, other than principal and interest due at the final Scheduled Payment
Date, by wire transfer of immediately available funds. Payment of the final
installment of principal payable with respect to this Bond shall be made as
provided in Section 8.5 of the Indenture (in the event this Bond is redeemed)
or shall be made upon presentation and surrender of this Bond at the Place of
Payment. All payments in respect of this Bond shall be made in such coin or
currency of the United States of America as at the time of payment is legal
tender for payment of debts.

                  Whenever any amount to be paid hereunder is stated to be due
on a day that is not a Business Day, such amount shall be payable on the next
succeeding Business Day and if such payment is timely made, no interest shall
accrue for the period from and after the day on which such payment was due.
Interest payments for this Bond will be computed and paid on the basis of a
360-day year consisting of twelve 30-day months.

                  Reference is made to the further provisions of this Bond set
forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if set forth at this place.

                  Unless the certificate of authentication hereon has been
executed by the Trustee by manual signature, this Bond shall not be entitled to
any benefit under the Indenture, or be valid or obligatory for any purpose.

                  IN WITNESS WHEREOF, the Company has caused this instrument to
be duly executed.

                                                    NRG NORTHEAST GENERATING LLC

                                                     By
                                                       -------------------------
                                                      Name:
                                                      Title:

                                       5
<PAGE>   65

                          CERTIFICATE OF AUTHENTICATION

                  This Bond is one of the Bonds referred to in the
within-mentioned Indenture.

THE CHASE MANHATTAN BANK,
as Trustee

By:
   --------------------------------
   Authorized Signatory

                                       6
<PAGE>   66

                       [Form of reverse of Global Bond for
                 8.842% Series B Senior Secured Bonds Due 2015]

                          NRG NORTHEAST GENERATING LLC
                  8.842% SERIES B SENIOR SECURED BOND DUE 2015

                  This bond is one of an authorized issue of Bonds of the
Company known as its 8.842% Series B Senior Secured Bonds Due 2010 (the
"Bonds"). The Bonds are issued under the Indenture dated as of February 22, 2000
(the "Original Indenture") among the Company, the Guarantors party thereto and
The Chase Manhattan Bank, a New York banking corporation, as trustee (in such
capacity, together with its successors in such capacity, the "Trustee"), as
supplemented by the First Supplemental Indenture dated as of February 22, 2000
(the "First Supplemental Indenture") among the Company, the Guarantors party
thereto and the Trustee (the Original Indenture, as so supplemented, and as the
same may be amended, modified and further supplemented, the "Indenture"). All
capitalized terms used herein, unless otherwise defined herein, shall have the
meanings ascribed to them in the Indenture.

                  All Bonds of any series issued and Outstanding under the
Indenture rank on a parity with each other Bond of the same series and with all
Bonds of each other series. Reference is hereby made to the Indenture for a
description of the nature and extent of the Bonds and the respective rights,
limitations of rights, duties and immunities thereunder of the Holders and of
the Trustee and the Company in respect of the Bonds and the terms upon which the
Bonds are made and are to be authenticated and delivered.

                  The principal of and interest on, this Bond are (i) guaranteed
by the Guarantors and (ii) secured by assets subject to the Lien of the
Collateral Documents, and all payments of principal and interest shall be made
in accordance with the terms of the Indenture. Each Holder, by acceptance of
this Bond, hereby acknowledges and agrees that (a) subject to the terms of
Section 10.2 of the Original Indenture, it will look solely to the assets of the
Company, the other Collateral purported to be covered under the Collateral
Documents and the income and proceeds received by the Trustee therefrom to the
extent available for distribution to such Holder as herein provided or provided
in the Collateral Documents, (b) none of the Members, or any of their respective
past, present or future members, officers, partners, directors or shareholders
or other Related Persons, or the Trustee shall be personally or otherwise liable
to any Holder, nor shall the Members, nor any of their respective past, present
or future members, officers, partners, directors or shareholders or other
Related Persons, be personally or otherwise liable to the Trustee for any
amounts payable under any Bond or for any liability under the Indenture or any
other Transaction Document, except as provided in the Original Indenture and (c)
recourse for any such amounts payable shall be otherwise limited in accordance
with Section 2.14 and Section 17.1 of the Original Indenture.

                  The obligations of the Company to pay the principal of and
interest on the Bonds when due as herein prescribed are absolute and
unconditional and no provision of this Bond or the Indenture shall alter or
impair such obligations.
                                       7
<PAGE>   67

                  The Bonds are subject to a Security Agreement dated as of
February 22, 2000 pursuant to which the rights of the Secured Parties (including
the Holders and the Trustee) in respect of the Collateral will be shared among
the Secured Parties and will be exercised by the Collateral Agent in accordance
with the Security Agreement.

                  The Indenture permits, with certain exceptions, as therein
provided, the amendment thereof and the modification of the rights and
obligations of the Company and the rights of the Holder under the Indenture at
any time by the Company with the consent of the Holders of not less than a
majority in aggregate principal amount of the Bonds of all series then
Outstanding. The Indenture also contains provisions permitting the Holders of
specified percentages in aggregate principal amount of the Bonds of all series
then Outstanding, on behalf of the Holders of all the Bonds, to waive compliance
by the Company with certain provisions of the Indenture and certain past
defaults under the Indenture and their consequences. Any Act (as such term is
defined in the Indenture), including, but not limited to, such a consent, waiver
or direction by the Holder of this Bond shall be conclusive and binding upon the
Holder and upon all future Holders of this Bond and the Holder of every Bond
issued upon the transfer hereof or the exchange herefor or in lieu hereof
whether or not notation of such Act is made upon this Bond.

                  This Bond is one of the series designated on the face hereof,
limited to $130,000,000 in aggregate principal amount as provided in the First
Supplemental Indenture.

                  This Bond and all Bonds issued or to be issued in series
created under the First Supplemental Indenture are (i) redeemable at the option
of the Company in accordance with Section 8.2 of the Indenture, on not less than
30 nor more than 60 days' notice, at a redemption price equal to the principal
amount thereof plus unpaid and accrued interest plus the Make-Whole Premium and
(ii) not subject to any sinking fund.

                  The Bonds are, under certain conditions, subject to mandatory
redemption as set forth in Section 8.3 of the Indenture. Notice of any
redemption of Bonds will be given at least 30 days but not more than 60 days
before the Redemption Date to each Holder at its address as it appears in the
Security Register.

                  Bonds (or portions thereof as aforesaid) for the redemption of
which provision is made in accordance with the Indenture shall cease to bear
interest from and after any Redemption Date.

                  The Indenture contains provisions for, upon compliance by the
Company with certain conditions set forth in the Indenture, the defeasance of
(a) the entire indebtedness of this Bond and (b) certain restrictive covenants
and agreements.

                  The unpaid portion of the Principal Amount, together with any
interest accrued and unpaid thereon and all other amounts due hereunder, if any,
may become due and payable upon the occurrence and continuation of any Event of
Default, but only as provided in the Indenture.

                  The Company and the Guarantors have entered into an Exchange
and Registration Rights Agreement dated February 15, 2000 (the "Registration
Rights Agreement") with the

                                       8
<PAGE>   68

Initial Purchasers described therein. Pursuant to such Registration Rights
Agreement, the Company and the Guarantors have agreed to file with the SEC a
registration statement under the Securities Act ("Registration Statement") for
an offer to exchange the Bonds for a like aggregate principal amount of Bonds
issued pursuant to the Indenture that are in all material respects identical to
the Bonds except that such exchange Bonds shall be issued pursuant to an
effective Registration Statement.

                  From and after the date on which a Registration Default (as
defined in the Registration Rights Agreement) occurs, the interest rate payable
on this Bond shall increase (in addition to the interest rate set forth above)
and additional interest reflecting such increase shall accrue with respect to
this Bond, until but not including the date on which such Registration Default
shall cease to exist (and provided no other Registration Default with respect to
this Bond shall then be continuing), at the rate of one half of one percent
(0.50%) per annum, which additional interest shall be payable hereon at the
times, in the manner and subject to the same terms and conditions set forth
herein and in the Indenture, as though the interest rate set forth above had
been increased by one half of one percent (0.50%) per annum.

                  The Bonds are issuable only as registered Bonds without
coupons in minimum denominations of $100,000 and any integral multiple of $1,000
in excess thereof. As provided in, and subject to the provisions of, the
Indenture, Bonds are exchangeable at the option of the Holder thereof for other
Bonds of the same series, of authorized denomination and of like tenor,
maturity, interest rate and aggregate principal amount, to be registered in the
name of such Holder, upon surrender thereof by such Holder at any office or
agency maintained for such purpose pursuant to the Indenture.

                  No service charge will be required of any Holder participating
in any such transfer or exchange of Bonds in respect of such transfer or
exchange, but the Security Registrar may require payment of a sum sufficient to
cover any tax or other governmental charge payable in connection therewith.

                  The person in whose name this Bond is registered shall be
deemed to be the owner and holder hereof for the purpose of receiving payment as
herein provided and for all other purposes whether or not this Bond be overdue
regardless of any notice to anyone to the contrary.

                  Bonds actually known to a Responsible Officer of the Trustee
to be owned or held by, or for the account or benefit of, the Company, the
Guarantors, or an Affiliate of any of the foregoing shall not be entitled to
share in any payment or distribution provided for in Article 10 of the Indenture
until all Bonds held by other Persons have been indefeasibly paid in full.

                  THIS BOND SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE
WITH, THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO PRINCIPLES OF
CONFLICTS OF LAW THEREOF TO THE EXTENT THE APPLICATION OF SUCH PRINCIPLES WOULD
CAUSE THE APPLICATION OF THE LAWS OF ANY OTHER JURISDICTION.

                                       9

<PAGE>   69

                                  ABBREVIATIONS

                  The following abbreviations when used in the inscription on
the face of this instrument shall be CONSTRUED as though they were written out
in full according to applicable laws or regulations:

         TEN COM  --       as tenants in common
         TEN ENT  --       as tenants by the entireties
          JT TEN  --       as joint tenants with right of
                           survivorship and not as tenants in
                           common

                        UNIF GIFT MIN ACT
                                          -------------------------------------
                                                      (Cust)   (Minor)

                                          under Uniform Gift to Minors Act

                                          --------------------------------------
                                                          (State)

                Additional abbreviations may also be used though
                              not in the above list

                              -------------------

                                       10
<PAGE>   70

                  FOR VALUE-RECEIVED the undersigned hereby sell(s), assign(s)
and transfer(s) unto

Social Security Number or Other
Identifying Number of Assignee
                                -----------------------------------------------

-------------------------------------------------------------------------------

-------------------------------------------------------------------------------

-------------------------------------------------------------------------------
                  (Please print or typewrite name and address,
                         including zip code of Assignee)

the within Security and all rights thereunder, hereby irrevocably constituting
and appointing attorney to transfer said Security on the books of the Company,
with full power of substitution in the premises.

Dated:
       ---------------------
                                                 ------------------------------
                                                 NAME:

NOTICE:           The signature to this assignment must correspond with the name
                  as written upon the first page of the within instrument in
                  every particular, without alteration or enlargement or any
                  change whatsoever.

                                       11
<PAGE>   71

                                                                     ANNEX A TO
                                   8.842% SERIES B SENIOR SECURED BOND DUE 2015

                  The following table sets forth the date of each semiannual
installment of the aggregate principal to be paid on all Bonds of this series on
each such date:

<TABLE>
<CAPTION>

                                                                     PRINCIPAL
                                                                        AMOUNT
                           PRINCIPAL                                   PAYABLE
                             PAYMENT                                 ON SERIES
                               DATES                                   B BONDS
                               -----                                   -------
<S>                                                              <C>
                       June 15, 2007                               $16,500,000
                   December 15, 2007                                16,500,000
                       June 15, 2008                                17,000,000
                   December 15, 2008                                17,000,000
                       June 15, 2009                                19,000,000
                   December 15, 2009                                19,000,000
                       June 15, 2010                                 2,000,000
                   December 15, 2010                                 2,000,000
                       June 15, 2011                                 2,000,000
                   December 15, 2011                                 2,000,000
                       June 15, 2012                                 2,000,000
                   December 15, 2012                                 2,000,000
                       June 15, 2013                                 2,500,000
                   December 15, 2013                                 2,500,000
                       June 15, 2014                                 2,500,000
                   December 15, 2014                                 2,500,000
                       June 15, 2015                                 3,000,000
                               TOTAL                              $130,000,000

</TABLE>

<PAGE>   72

                                                                     ANNEX B TO
                                   8.842% SERIES B SENIOR SECURED BOND DUE 2015

        Exchanges of portions of this Global Bond for definitive Bonds:

<TABLE>
<CAPTION>
====================================================================================================================
<S>                     <C>                                   <C>                               <C>
                         PRINCIPAL AMOUNT OF
                         DEFINITIVE SECURITIES ISSUED           REMAINING PRINCIPAL
                         IN EXCHANGE FOR A                      AMOUNT OF THIS GLOBAL            NOTATION MADE
DATE                     PORTION OF THIS GLOBAL SECURITY        SECURITY                         BY
---------------------------------------------------------------------------------------------------------------------

---------------------------------------------------------------------------------------------------------------------

---------------------------------------------------------------------------------------------------------------------

---------------------------------------------------------------------------------------------------------------------

---------------------------------------------------------------------------------------------------------------------

---------------------------------------------------------------------------------------------------------------------

---------------------------------------------------------------------------------------------------------------------

---------------------------------------------------------------------------------------------------------------------

======================== ===================================== ============================== ======================
</TABLE>

<PAGE>   73

                                                           Schedule 3-A to First
                                                       Supplemental Indenture to
                                              NRG Northeast Generating Indenture

                          [Form of face of definitive
                 9.292% Series C Senior Secured Bonds Due 2024]

                          NRG NORTHEAST GENERATING LLC
                  9.292% SERIES C SENIOR SECURED BOND DUE 2024

                  THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT
OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR THE SECURITIES LAWS OF ANY STATE
OR OTHER JURISDICTION. NEITHER THIS SECURITY NOR ANY INTEREST OR PARTICIPATION
HEREIN MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR
OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH
TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, SUCH REGISTRATION.

                  THE HOLDER OF THIS SECURITY BY ITS ACCEPTANCE HEREOF AGREES TO
OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE "RESALE
RESTRICTION TERMINATION DATE") WHICH IS TWO YEARS AFTER THE LATER OF THE
ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH THE ISSUER OR ANY
AFFILIATE OF THE ISSUER WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF
SUCH SECURITY), ONLY (A) TO THE ISSUER, (B) PURSUANT TO A REGISTRATION STATEMENT
THAT HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT, (C) FOR SO LONG AS
THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THE
SECURITIES ACT ("RULE 144A"), TO A PERSON IT REASONABLY BELIEVES IS A "QUALIFIED
INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A THAT PURCHASES FOR ITS OWN ACCOUNT
OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN
THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (D) PURSUANT TO OFFERS
AND SALES THAT OCCUR OUTSIDE THE UNITED STATES WITHIN THE MEANING OF REGULATION
S UNDER THE SECURITIES ACT, (E) TO AN INSTITUTIONAL "ACCREDITED INVESTOR" WITHIN
THE MEANING OF RULE 501(a)(1), (2), (3) OR (7) UNDER THE SECURITIES ACT THAT IS
AN INSTITUTIONAL INVESTOR ACQUIRING THE SECURITY FOR ITS OWN ACCOUNT OR FOR THE
ACCOUNT OF SUCH AN INSTITUTIONAL ACCREDITED INVESTOR, IN EACH CASE IN A MINIMUM
PRINCIPAL AMOUNT OF THE SECURITIES OF $250,000, FOR INVESTMENT PURPOSES AND NOT
WITH A VIEW TO OR FOR OFFER OR SALE IN CONNECTION WITH ANY DISTRIBUTION IN
VIOLATION OF THE SECURITIES ACT OR (F) PURSUANT TO ANY OTHER AVAILABLE EXEMPTION
FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE
ISSUER'S AND THE TRUSTEE'S RIGHTS PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER
PURSUANT

<PAGE>   74

TO CLAUSES (D), (E) OR (F) TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL,
CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO EACH OF THEM AND IN THE
CASE OF THE FOREGOING CLAUSE (E), A CERTIFICATE OF TRANSFER (A FORM OF WHICH
MAY BE OBTAINED FROM THE ISSUER OR THE TRUSTEE) COMPLETED AND DELIVERED BY THE
TRANSFEROR TO THE ISSUER AND THE TRUSTEE. THIS LEGEND WILL BE REMOVED UPON THE
REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE.

                                       2
<PAGE>   75

No.                                                              CUSIP NUMBER
                                                                     [    ]

<TABLE>
<CAPTION>

<S>                                 <C>                                          <C>
Principal Amount                          Final Scheduled Payment Date              Issue Date
----------------                          ----------------------------              ----------

$[___________]                                  December 15, 2024                   February 22, 2000

         REGISTERED HOLDER:                 [_______________]

         PRINCIPAL AMOUNT:                  [_______________] Dollars

         INTEREST RATE:                     9.292%

</TABLE>

                  NRG NORTHEAST GENERATING LLC, a Delaware limited liability
company (hereinafter called the "Company", which term includes any successor or
assign under the Indenture referred to below), for value received hereby
promises to pay to [____________], or its registered assigns, the outstanding
Principal Amount hereof, such payment to be made in semiannual installments on
June 15 and December 15 of each year (commencing December 15, 2015) and ending
on the final Scheduled Payment Date set forth above, each such installment to be
in the amount and payable on the date set forth on Annex A attached hereto
(provided that the portion of the Principal Amount remaining unpaid on the final
Scheduled Payment Date, together with all interest accrued thereon, shall in any
and all cases be due and payable on the final Scheduled Payment Date), and to
pay interest on the unpaid portion of the Principal Amount at the interest rate
set forth above (subject to the fourteenth paragraph set forth on the reverse of
this Bond, which refers to a Registration Default) from the most recent
Scheduled Payment Date to which interest has been paid or duly provided for or,
if no interest has been paid or duly provided for, from the issue date set forth
above, semiannually on June 15 and December 15 in each year (commencing June 15,
2000) until the Principal Amount is paid in full or payment thereof is duly
provided for. Any installment of principal and, to the extent permitted by
applicable law, any payment of interest not punctually paid or duly provided for
shall continue to bear interest at a rate equal to the interest rate set forth
above. The principal and interest so payable, and punctually paid or duly
provided for, at any Scheduled Payment Date shall, as provided in the Indenture,
be paid to the Person in whose name this Bond (or one or more Predecessor Bonds)
is registered in the Security Register at the close of business on the Regular
Record Date for such payment of principal and interest, which shall be June 1 or
December 1, as the case may be (whether or not a Business Day), next preceding
such Scheduled Payment Date. Any such principal and interest that is payable,
but is not so punctually paid or duly provided for at any Scheduled Payment
Date, shall forthwith cease to be payable to the Holder hereof on such Regular
Record Date, and may be paid to the Person in whose name this Bond (or one or
more Predecessor Bonds) is registered at the close of business on a Special
Record Date for the payment of such defaulted principal and interest (together
with any other amounts payable with respect to such principal and interest), to
be fixed by the Trustee, notice of which shall be given to the Holder hereof not
less than 10 days prior to such Special Record Date, or may be paid at any time
in any other lawful manner not inconsistent with the requirements of any
securities exchange on which this Bond may be listed, and upon such notice as
may be required by such
                                       3
<PAGE>   76
exchange, all as more fully provided in the Indenture. Payments of principal of
and interest on this Bond shall be made (i) if the Company so elects, by check
mailed to the Holder at his or her registered address or (ii) otherwise, at the
Place of Payment; provided, that the final installment of principal payable with
respect to this Bond shall be made as provided in Section 8.5 of the Indenture
(in the event this Bond is redeemed) or shall be made upon presentation and
surrender of this Bond at the Place of Payment. All payments in respect of this
Bond shall be made in such coin or currency of the United States of America as
at the time of payment is legal tender for payment of debts.

                  Whenever any amount to be paid hereunder is stated to be due
on a day that is not a Business Day, such amount shall be payable on the next
succeeding Business Day and if such payment is timely made, no interest shall
accrue for the period from and after the day on which such payment was due.
Interest payments for this Bond will be computed and paid on the basis of a
360-day year consisting of twelve 30-day months.

                  Reference is made to the further provisions of this Bond set
forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if set forth at this place.

                  Unless the certificate of authentication hereon has been
executed by the Trustee by manual signature, this Bond shall not be entitled to
any benefit under the Indenture, or be valid or obligatory for any purpose.

                  IN WITNESS WHEREOF, the Company has caused this instrument to
be duly executed.

                                                   NRG NORTHEAST GENERATING LLC

                                                   By
                                                     -------------------------
                                                    Name:
                                                    Title:

                                       4
<PAGE>   77

                          CERTIFICATE OF AUTHENTICATION

                  This Bond is one of the Bonds referred to in the
within-mentioned Indenture.

THE CHASE MANHATTAN BANK,
   as Trustee

By:
   --------------------------------
   Authorized Signatory

                                       5
<PAGE>   78

                         [Form of reverse of definitive
                  9.292% Series C Senior Secured Bonds Due 2024]

                          NRG NORTHEAST GENERATING LLC
                  9.292% SERIES C SENIOR SECURED BOND DUE 2024

                  This bond is one of an authorized issue of Bonds of the
Company known as its 9.292% Series C Senior Secured Bonds Due 2024 (the
"Bonds"). The Bonds are issued under the Indenture dated as of February 22, 2000
(the "Original Indenture") among the Company, the Guarantors party thereto and
The Chase Manhattan Bank, a New York banking corporation, as trustee (in such
capacity, together with its successors in such capacity, the "Trustee"), as
supplemented by the First Supplemental Indenture dated as of February 22, 2000
(the "First Supplemental Indenture") among the Company, the Guarantors party
thereto and the Trustee (the Original Indenture, as so supplemented, and as the
same may be amended, modified and further supplemented, the "Indenture"). All
capitalized terms used herein, unless otherwise defined herein, shall have the
meanings ascribed to them in the Indenture.

                  All Bonds of any series issued and Outstanding under the
Indenture rank on a parity with each other Bond of the same series and with all
Bonds of each other series. Reference is hereby made to the Indenture for a
description of the nature and extent of the Bonds and the respective rights,
limitations of rights, duties and immunities thereunder of the Holders and of
the Trustee and the Company in respect of the Bonds and the terms upon which the
Bonds are made and are to be authenticated and delivered.

                  The principal of and interest on, this Bond are (i) guaranteed
by the Guarantors and (ii) secured by assets subject to the Lien of the
Collateral Documents, and all payments of principal and interest shall be made
in accordance with the terms of the Indenture. Each Holder, by acceptance of
this Bond, hereby acknowledges and agrees that (a) subject to the terms of
Section 10.2 of the Original Indenture, it will look solely to the assets of the
Company, the other Collateral purported to be covered under the Collateral
Documents and the income and proceeds received by the Trustee therefrom to the
extent available for distribution to such Holder as herein provided or provided
in the Collateral Documents, (b) none of the Members, or any of their respective
past, present or future members, officers, partners, directors or shareholders
or other Related Persons, or the Trustee shall be personally or otherwise liable
to any Holder, nor shall the Members, nor any of their respective past, present
or future members, officers, partners, directors or shareholders or other
Related Persons, be personally or otherwise liable to the Trustee for any
amounts payable under any Bond or for any liability under the Indenture or any
other Transaction Document, except as provided in the Original Indenture and (c)
recourse for any such amounts payable shall be otherwise limited in accordance
with Section 2.14 and Section 17.1 of the Original Indenture.

                  The obligations of the Company to pay the principal of and
interest on the Bonds when due as herein prescribed are absolute and
unconditional and no provision of this Bond or the Indenture shall alter or
impair such obligations.
                                       6
<PAGE>   79

                  The Bonds are subject to a Security Agreement dated as of
February 22, 2000 pursuant to which the rights of the Secured Parties (including
the Holders and the Trustee) in respect of the Collateral will be shared among
the Secured Parties and will be exercised by the Collateral Agent in accordance
with the Security Agreement.

                  The Indenture permits, with certain exceptions, as therein
provided, the amendment thereof and the modification of the rights and
obligations of the Company and the rights of the Holder under the Indenture at
any time by the Company with the consent of the Holders of not less than a
majority in aggregate principal amount of the Bonds of all series then
Outstanding. The Indenture also contains provisions permitting the Holders of
specified percentages in aggregate principal amount of the Bonds of all series
then Outstanding, on behalf of the Holders of all the Bonds, to waive compliance
by the Company with certain provisions of the Indenture and certain past
defaults under the Indenture and their consequences. Any Act (as such term is
defined in the Indenture), including, but not limited to, such a consent, waiver
or direction by the Holder of this Bond shall be conclusive and binding upon the
Holder and upon all future Holders of this Bond and the Holder of every Bond
issued upon the transfer hereof or the exchange herefor or in lieu hereof
whether or not notation of such Act is made upon this Bond.

                  This Bond is one of the series designated on the face hereof,
limited to $300,000,000 in aggregate principal amount as provided in the First
Supplemental Indenture.

                  This Bond and all Bonds issued or to be issued in series
created under the First Supplemental Indenture are (i) redeemable at the option
of the Company in accordance with Section 8.2 of the Indenture, on not less than
30 nor more than 60 days' notice, at a redemption price equal to the principal
amount thereof plus unpaid and accrued interest plus the Make-Whole Premium and
(ii) not subject to any sinking fund.

                  The Bonds are, under certain conditions, subject to mandatory
redemption as set forth in Section 8.3 of the Indenture. Notice of any
redemption of Bonds will be given at least 30 days but not more than 60 days
before the Redemption Date to each Holder at its address as it appears in the
Security Register.

                  Bonds (or portions thereof as aforesaid) for the redemption of
which provision is made in accordance with the Indenture shall cease to bear
interest from and after any Redemption Date.

                  The Indenture contains provisions for, upon compliance by the
Company with certain conditions set forth in the Indenture, the defeasance of
(a) the entire indebtedness of this Bond and (b) certain restrictive covenants
and agreements.

                  The unpaid portion of the Principal Amount, together with any
interest accrued and unpaid thereon and all other amounts due hereunder, if any,
may become due and payable upon the occurrence and continuation of any Event of
Default, but only as provided in the Indenture.

                  The Company and the Guarantors have entered into an Exchange
and Registration Rights Agreement dated February 15, 2000 (the "Registration
Rights Agreement") with the

<PAGE>   80
                  The Bonds are subject to a Security Agreement dated as of
February 22, 2000 pursuant to which the rights of the Secured Parties (including
the Holders and the Trustee) in respect of the Collateral will be shared among
the Secured Parties and will be exercised by the Collateral Agent in accordance
with the Security Agreement.

                  The Indenture permits, with certain exceptions, as therein
provided, the amendment thereof and the modification of the rights and
obligations of the Company and the rights of the Holder under the Indenture at
any time by the Company with the consent of the Holders of not less than a
majority in aggregate principal amount of the Bonds of all series then
Outstanding. The Indenture also contains provisions permitting the Holders of
specified percentages in aggregate principal amount of the Bonds of all series
then Outstanding, on behalf of the Holders of all the Bonds, to waive compliance
by the Company with certain provisions of the Indenture and certain past
defaults under the Indenture and their consequences. Any Act (as such term is
defined in the Indenture), including, but not limited to, such a consent, waiver
or direction by the Holder of this Bond shall be conclusive and binding upon the
Holder and upon all future Holders of this Bond and the Holder of every Bond
issued upon the transfer hereof or the exchange herefor or in lieu hereof
whether or not notation of such Act is made upon this Bond.

                  This Bond is one of the series designated on the face hereof,
limited to $300,000,000 in aggregate principal amount as provided in the First
Supplemental Indenture.

                  This Bond and all Bonds issued or to be issued in series
created under the First Supplemental Indenture are (i) redeemable at the option
of the Company in accordance with Section 8.2 of the Indenture, on not less than
30 nor more than 60 days' notice, at a redemption price equal to the principal
amount thereof plus unpaid and accrued interest plus the Make-Whole Premium and
(ii) not subject to any sinking fund.

                  The Bonds are, under certain conditions, subject to mandatory
redemption as set forth in Section 8.3 of the Indenture. Notice of any
redemption of Bonds will be given at least 30 days but not more than 60 days
before the Redemption Date to each Holder at its address as it appears in the
Security Register.

                  Bonds (or portions thereof as aforesaid) for the redemption of
which provision is made in accordance with the Indenture shall cease to bear
interest from and after any Redemption Date.

                  The Indenture contains provisions for, upon compliance by the
Company with certain conditions set forth in the Indenture, the defeasance of
(a) the entire indebtedness of this Bond and (b) certain restrictive covenants
and agreements.

                  The unpaid portion of the Principal Amount, together with any
interest accrued and unpaid thereon and all other amounts due hereunder, if any,
may become due and payable upon the occurrence and continuation of any Event of
Default, but only as provided in the Indenture.

                  The Company and the Guarantors have entered into an Exchange
and Registration Rights Agreement dated February 15, 2000 (the "Registration
Rights Agreement") with the

                                       7
<PAGE>   81
Initial Purchasers described therein. Pursuant to such Registration Rights
Agreement, the Company and the Guarantors have agreed to file with the SEC a
registration statement under the Securities Act ("Registration Statement") for
an offer to exchange the Bonds for a like aggregate principal amount of Bonds
issued pursuant to the Indenture that are in all material respects identical to
the Bonds except that such exchange Bonds shall be issued pursuant to an
effective Registration Statement.

                  From and after the date on which a Registration Default (as
defined in the Registration Rights Agreement) occurs, the interest rate payable
on this Bond shall increase (in addition to the interest rate set forth above)
and additional interest reflecting such increase shall accrue with respect to
this Bond, until but not including the date on which such Registration Default
shall cease to exist (and provided no other Registration Default with respect to
this Bond shall then be continuing), at the rate of one half of one percent
(0.50%) per annum, which additional interest shall be payable hereon at the
times, in the manner and subject to the same terms and conditions set forth
herein and in the Indenture, as though the interest rate set forth above had
been increased by one half of one percent (0.50%) per annum.

                  The Bonds are issuable only as registered Bonds without
coupons in minimum denominations of $100,000 and any integral multiple of $1,000
in excess thereof. As provided in, and subject to the provisions of, the
Indenture, Bonds are exchangeable at the option of the Holder thereof for other
Bonds of the same series, of authorized denomination and of like tenor,
maturity, interest rate and aggregate principal amount, to be registered in the
name of such Holder, upon surrender thereof by such Holder at any office or
agency maintained for such purpose pursuant to the Indenture.

                  No service charge will be required of any Holder participating
in any such transfer or exchange of Bonds in respect of such transfer or
exchange, but the Security Registrar may require payment of a sum sufficient to
cover any tax or other governmental charge payable in connection therewith.

                  The person in whose name this Bond is registered shall be
deemed to be the owner and holder hereof for the purpose of receiving payment as
herein provided and for all other purposes whether or not this Bond be overdue
regardless of any notice to anyone to the contrary.

                  Bonds actually known to a Responsible Officer of the Trustee
to be owned or held by, or for the account or benefit of, the Company, the
Guarantors, or an Affiliate of any of the foregoing shall not be entitled to
share in any payment or distribution provided for in Article 10 of the Indenture
until all Bonds held by other Persons have been indefeasibly paid in full.

                  THIS BOND SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE
WITH, THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO PRINCIPLES OF
CONFLICTS OF LAW THEREOF TO THE EXTENT THE APPLICATION OF SUCH PRINCIPLES WOULD
CAUSE THE APPLICATION OF THE LAWS OF ANY OTHER JURISDICTION.

                                       8
<PAGE>   82

                                                                      ANNEX A TO
                                    9.292% SERIES C SENIOR SECURED BOND DUE 2024

                  The following table sets forth the date of each semiannual
installment of the aggregate principal to be paid on all Bonds of this series on
each such date:

<TABLE>
<CAPTION>

                                                           PRINCIPAL
                                                              AMOUNT
                           PRINCIPAL                         PAYABLE
                             PAYMENT                       ON SERIES
                               DATES                         C BONDS
<S>                                                       <C>
                   December 15, 2015                      $3,000,000
                       June 15, 2016                       3,000,000
                   December 15, 2016                       3,000,000
                       June 15, 2017                       3,500,000
                   December 15, 2017                       3,500,000
                       June 15, 2018                      15,500,000
                   December 15, 2018                      15,500,000
                       June 15, 2019                      17,000,000
                   December 15, 2019                      17,000,000
                       June 15, 2020                      18,500,000
                   December 15, 2020                      18,500,000
                       June 15, 2021                      20,000,000
                   December 15, 2021                      20,000,000
                       June 15, 2022                      22,000,000
                   December 15, 2022                      22,000,000
                       June 15, 2023                      23,000,000
                   December 15, 2023                      23,000,000
                       June 15, 2024                      26,000,000
                   December 15, 2024                      26,000,000
                               TOTAL                    $300,000,000
</TABLE>

                                       9
<PAGE>   83

                                  ABBREVIATIONS

                  The following abbreviations when used in the inscription on
the face of this instrument shall be construed as though they were written out
in full according to applicable laws or regulations:

         TEN COM  --       as tenants in common
         TEN ENT  --       as tenants by the entireties
          JT TEN  --       as joint tenants with right of
                           survivorship and not as tenants in
                           common

                  UNIF GIFT MIN ACT
                                       -----------------------------------------
                                                        (Cust) (Minor)

                                       under Uniform Gift to Minors Act

                                       -----------------------------------------
                                                         (State)

                Additional abbreviations may also be used though
                              not in the above list

                               -------------------

                                       10
<PAGE>   84

                  FOR VALUE-RECEIVED the undersigned hereby sell(s), assign(s)
and transfer(s) unto

Identifying Number of Assignee
                              --------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
                  (Please print or typewrite name and address,
                         including zip code of Assignee)

the within Bond and all rights thereunder, hereby irrevocably constituting and
appointing attorney to transfer said Bond on the books of the Company, with full
power of substitution in the premises.

Dated:
       ---------------------

                                                ------------------------------
                                                NAME:

NOTICE:           The signature to this assignment must correspond with the name
                  as written upon the first page of the within instrument in
                  every particular, without alteration or enlargement or any
                  change whatsoever.

                                       11
<PAGE>   85

                                                           Schedule 3-B to First
                                                          Supplemental Indenture

                          [Form of face of Global Bond
               for 9.292% Series C Senior Secured Bonds Due 2024]

                          NRG NORTHEAST GENERATING LLC
                  9.292% SERIES C SENIOR SECURED BOND DUE 2024

                  [Insert in Rule 144A Global Bonds -- THIS SECURITY HAS NOT
BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES
ACT"), OR THE SECURITIES LAWS OF ANY STATE OR OTHER JURISDICTION. NEITHER THIS
SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN MAY BE REOFFERED, SOLD,
ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE
ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT
SUBJECT TO, SUCH REGISTRATION.

                  THE HOLDER OF THIS SECURITY BY ITS ACCEPTANCE HEREOF AGREES TO
OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE "RESALE
RESTRICTION TERMINATION DATE") WHICH IS TWO YEARS AFTER THE LATER OF THE
ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH THE ISSUER OR ANY
AFFILIATE OF THE ISSUER WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF
SUCH SECURITY), ONLY (A) TO THE ISSUER, (B) PURSUANT TO A REGISTRATION STATEMENT
THAT HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT, (C) FOR SO LONG AS
THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THE
SECURITIES ACT ("RULE 144A"), TO A PERSON IT REASONABLY BELIEVES IS A "QUALIFIED
INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A THAT PURCHASES FOR ITS OWN ACCOUNT
OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN
THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (D) PURSUANT TO OFFERS
AND SALES THAT OCCUR OUTSIDE THE UNITED STATES WITHIN THE MEANING OF REGULATION
S UNDER THE SECURITIES ACT, (E) TO AN INSTITUTIONAL "ACCREDITED INVESTOR" WITHIN
THE MEANING OF RULE 501(a)(1), (2), (3) OR (7) UNDER THE SECURITIES ACT THAT IS
AN INSTITUTIONAL INVESTOR ACQUIRING THE SECURITY FOR ITS OWN ACCOUNT OR FOR THE
ACCOUNT OF SUCH AN INSTITUTIONAL ACCREDITED INVESTOR, IN EACH CASE IN A MINIMUM
PRINCIPAL AMOUNT OF THE SECURITIES OF $250,000, FOR INVESTMENT PURPOSES AND NOT
WITH A VIEW TO OR FOR OFFER OR SALE IN CONNECTION WITH ANY DISTRIBUTION IN
VIOLATION OF THE SECURITIES ACT OR (F) PURSUANT TO ANOTHER AVAILABLE EXEMPTION
FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE
ISSUER'S AND THE TRUSTEE'S RIGHTS PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER
PURSUANT

<PAGE>   86

TO CLAUSES (D), (E) OR (F) TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL,
CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO EACH OF THEM AND IN THE
CASE OF THE FOREGOING CLAUSE (E), A CERTIFICATE OF TRANSFER ( A FORM OF WHICH
MAY BE OBTAINED FROM THE ISSUER OR THE TRUSTEE) COMPLETED AND DELIVERED BY THE
TRANSFEROR TO THE ISSUER AND THE TRUSTEE. THIS LEGEND WILL BE REMOVED UPON THE
REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE. ]

                  [Insert in Regulation S Global Bonds -- THIS SECURITY HAS NOT
BEEN REGISTERED UNDER THE UNITED STATES SECURITIES ACT OF 1933, AS AMENDED (THE
"SECURITIES ACT"), AND ACCORDINGLY, MAY NOT BE OFFERED OR SOLD WITHIN THE UNITED
STATES OR TO OR FOR THE ACCOUNT OR BENEFIT OF, U.S. PERSONS EXCEPT AS SET FORTH
IN THE FOLLOWING SENTENCE. BY ITS ACQUISITION HEREOF, THE HOLDER (1) REPRESENTS
THAT IT IS NOT A U.S. PERSON AND IS ACQUIRING THIS SECURITY IN AN OFFSHORE
TRANSACTION, (2) BY ITS ACCEPTANCE HEREOF AGREES TO OFFER, SELL OR OTHERWISE
TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE "RESALE RESTRICTION TERMINATION
DATE") WHICH IS TWO YEARS AFTER THE LATER OF THE ORIGINAL ISSUE DATE HEREOF AND
THE LAST DATE ON WHICH THE ISSUER OR ANY AFFILIATE OF THE ISSUER WAS THE OWNER
OF THIS SECURITY (OR ANY PREDECESSOR OF SUCH SECURITY), ONLY (A) TO THE ISSUER,
(B) PURSUANT TO A REGISTRATION STATEMENT THAT HAS BEEN DECLARED EFFECTIVE UNDER
THE SECURITIES ACT, (C) FOR SO LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE
PURSUANT TO RULE 144A UNDER THE SECURITIES ACT ("RULE 144A"), TO A PERSON IT
REASONABLY BELIEVES IS A "QUALIFIED INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A
THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED
INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN
RELIANCE ON RULE 144A, (D) PURSUANT TO OFFERS AND SALES THAT OCCUR OUTSIDE THE
UNITED STATES WITHIN THE MEANING OF REGULATION S UNDER THE SECURITIES ACT, (E)
TO AN INSTITUTIONAL "ACCREDITED INVESTOR" WITHIN THE MEANING OF RULE 501(a)(1),
(2), (3) OR (7) UNDER THE SECURITIES ACT THAT IS AN INSTITUTIONAL INVESTOR
ACQUIRING THE SECURITY FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF SUCH AN
INSTITUTIONAL ACCREDITED INVESTOR, IN EACH CASE IN A MINIMUM PRINCIPAL AMOUNT OF
THE SECURITIES OF $250,000, FOR INVESTMENT PURPOSES AND NOT WITH A VIEW TO OR
FOR OFFER OR SALE IN CONNECTION WITH ANY DISTRIBUTION IN VIOLATION OF THE
SECURITIES ACT OR (F) PURSUANT TO ANOTHER AVAILABLE EXEMPTION FROM THE
REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE ISSUER'S AND THE
TRUSTEE'S RIGHTS PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER PURSUANT TO CLAUSES
(D), (E) OR (F) TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL, CERTIFICATION
AND/OR OTHER INFORMATION SATISFACTORY TO EACH OF THEM AND IN THE CASE OF THE
FOREGOING CLAUSE (E), A CERTIFICATE OF TRANSFER ( A FORM OF WHICH MAY BE
OBTAINED FROM THE ISSUER OR THE TRUSTEE) COMPLETED AND DELIVERED BY THE
TRANSFEROR TO THE ISSUER AND THE TRUSTEE. THIS LEGEND WILL BE

                                       2
<PAGE>   87

REMOVED AFTER 40 CONSECUTIVE DAYS BEGINNING ON AND INCLUDING THE LATER OF (A)
THE DAY ON WHICH THE SECURITIES ARE OFFERED TO PERSONS OTHER THAN DISTRIBUTORS
(AS DEFINED IN REGULATION S) AND (B) THE DATE OF THE CLOSING OF THE ORIGINAL
OFFERING. AS USED HEREIN, THE TERMS "OFFSHORE TRANSACTION", "UNITED STATES" AND
"U.S. PERSON" HAVE THE MEANINGS GIVEN TO THEM BY REGULATION S UNDER THE
SECURITIES ACT.]

                  UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED
REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY ("DTC") TO THE COMPANY OR ITS
AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE
ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER REPRESENTATIVE OF
DTC AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT
HEREON IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN
AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR
VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL SINCE THE REGISTERED OWNER
HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

                  TRANSFERS OF THIS GLOBAL BOND SHALL BE LIMITED TO TRANSFERS IN
WHOLE, BUT NOT IN PART, TO NOMINEES OF CEDE & CO. OR TO A SUCCESSOR THEREOF OR
SUCH SUCCESSOR'S NOMINEE AND TRANSFERS OF PORTIONS OF THIS GLOBAL BOND SHALL BE
LIMITED TO TRANSFERS MADE IN ACCORDANCE WITH THE RESTRICTIONS SET FORTH IN THE
INDENTURE.

                                       3
<PAGE>   88

No.                                                 [CUSIP] [CINS] [ISIN] NUMBER
                                                                 [ ]

<TABLE>
<CAPTION>

Principal Amount                          Final Scheduled Payment Date              Issue Date
----------------                          ----------------------------              ----------
<S>                                             <C>                                 <C>
$[___________]                                  December 15, 2024                   February 22, 2000
</TABLE>

         REGISTERED HOLDER:         CEDE & CO.

         PRINCIPAL AMOUNT:          [_________________] Dollars

         INTEREST RATE:             9.292%

                  NRG NORTHEAST GENERATING LLC, a Delaware limited liability
company (hereinafter called the "Company", which term includes any successor or
assign under the Indenture referred to below), for value received hereby
promises to pay to Cede & Co., or its registered assigns, the outstanding
Principal Amount hereof after subtracting the aggregate principal amount of any
definitive Bonds issued in exchange for a portion or portions hereof, such
payment to be made in semiannual installments on June 15 and December 15 of each
year (commencing December 15, 2015) and ending on the final Scheduled Payment
Date set forth above, each such installment to be in the amount and payable on
the date set forth on Annex A attached hereto (provided that the portion of the
Principal Amount remaining unpaid on the final Scheduled Payment Date, together
with all interest accrued thereon, shall in any and all cases be due and payable
on the final Scheduled Payment Date), and to pay interest on the unpaid portion
of the Principal Amount at the interest rate set forth above (subject to the
fourteenth paragraph set forth on the reverse of this Bond, which refers to a
Registration Default) from the most recent Scheduled Payment Date to which
interest has been paid or duly provided for or, if no interest has been paid or
duly provided for, from the issue date set forth above, semiannually on June 15
and December 15 in each year (commencing June 15, 2000), until the Principal
Amount is paid in full or payment thereof is duly provided for. Any installment
of principal and, to the extent permitted by applicable law, any payment of
interest not punctually paid or duly provided for shall continue to bear
interest at a rate equal to the interest rate set forth above. The principal and
interest so payable, and punctually paid or duly provided for, at any Scheduled
Payment Date shall, as provided in the Indenture, be paid to the Person in whose
name this Bond (or one or more Predecessor Bonds) is registered in the Security
Register at the close of business on the Regular Record Date for such payment of
principal and interest, which shall be June 1 or December 1, as the case may be
(whether or not a Business Day), next preceding Scheduled Payment Date. Any such
principal and interest that is payable, but is not so punctually paid or duly
provided for at any Scheduled Payment Date, shall forthwith cease to be payable
to the Holder hereof on such Regular Record Date, and may be paid to the Person
in whose name this Bond (or one or more Predecessor Bonds) is registered at the
close of business on a Special Record Date for the payment of such defaulted
principal and interest (together with any other amounts payable with respect to
such principal and interest), to be fixed by the Trustee, notice of which shall
be given to the Holder hereof not less than 10 days prior to such Special Record

                                       4
<PAGE>   89

Date, or may be paid at any time in any other lawful manner not inconsistent
with the requirements of any securities exchange on which this Bond may be
listed, and upon such notice as may be required by such exchange, all as more
fully provided in the Indenture. This being a Global Bond (as that term is
defined in the Indenture) deposited with DTC acting as depository, and
registered in the name of Cede & Co. a nominee of DTC, Cede & Co., as holder of
record of this Bond shall be entitled to receive payment of principal and
interest, other than principal and interest due at the final Scheduled Payment
Date, by wire transfer of immediately available funds. Payment of the final
installment of principal payable with respect to this Bond shall be made as
provided in Section 8.5 of the Indenture (in the event this Bond is redeemed) or
shall be made upon presentation and surrender of this Bond at the Place of
Payment. All payments in respect of this Bond shall be made in such coin or
currency of the United States of America as at the time of payment is legal
tender for payment of debts.

                  Whenever any amount to be paid hereunder is stated to be due
on a day that is not a Business Day, such amount shall be payable on the next
succeeding Business Day and if such payment is timely made, no interest shall
accrue for the period from and after the day on which such payment was due.
Interest payments for this Bond will be computed and paid on the basis of a
360-day year consisting of twelve 30-day months.

                  Reference is made to the further provisions of this Bond set
forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if set forth at this place.

                  Unless the certificate of authentication hereon has been
executed by the Trustee by manual signature, this Bond shall not be entitled to
any benefit under the Indenture, or be valid or obligatory for any purpose.

                  IN WITNESS WHEREOF, the Company has caused this instrument to
be duly executed.

                                                    NRG NORTHEAST GENERATING LLC

                                                     By
                                                       -------------------------
                                                       Name:
                                                       Title:

                                       5
<PAGE>   90

                          CERTIFICATE OF AUTHENTICATION

                  This Bond is one of the Bonds referred to in the
within-mentioned Indenture.

THE CHASE MANHATTAN BANK,
  as Trustee

By:
   --------------------------------
   Authorized Signatory

                                       6
<PAGE>   91

                       [Form of reverse of Global Bond for
                     Series C Senior Secured Bonds Due 2024]

                          NRG NORTHEAST GENERATING LLC
                  9.292% SERIES C SENIOR SECURED BOND DUE 2024

                  This bond is one of an authorized issue of Bonds of the
Company known as its 9.292% Series C Senior Secured Bonds Due 2024 (the
"Bonds"). The Bonds are issued under the Indenture dated as of February 22, 2000
(the "Original Indenture") among the Company, the Guarantors party thereto and
The Chase Manhattan Bank, a New York banking corporation, as trustee (in such
capacity, together with its successors in such capacity, the "Trustee"), as
supplemented by the First Supplemental Indenture dated as of February 22, 2000
(the "First Supplemental Indenture") among the Company, the Guarantors party
thereto and the Trustee (the Original Indenture, as so supplemented, and as the
same may be amended, modified and further supplemented, the "Indenture"). All
capitalized terms used herein, unless otherwise defined herein, shall have the
meanings ascribed to them in the Indenture.

                  All Bonds of any series issued and Outstanding under the
Indenture rank on a parity with each other Bond of the same series and with all
Bonds of each other series. Reference is hereby made to the Indenture for a
description of the nature and extent of the Bonds and the respective rights,
limitations of rights, duties and immunities thereunder of the Holders and of
the Trustee and the Company in respect of the Bonds and the terms upon which the
Bonds are made and are to be authenticated and delivered.

                  The principal of and interest on, this Bond are (i) guaranteed
by the Guarantors and (ii) secured by assets subject to the Lien of the
Collateral Documents, and all payments of principal and interest shall be made
in accordance with the terms of the Indenture. Each Holder, by acceptance of
this Bond, hereby acknowledges and agrees that (a) subject to the terms of
Section 10.2 of the Original Indenture, it will look solely to the assets of the
Company, the other Collateral purported to be covered under the Collateral
Documents and the income and proceeds received by the Trustee therefrom to the
extent available for distribution to such Holder as herein provided or provided
in the Collateral Documents, (b) none of the Members, or any of their respective
past, present or future members, officers, partners, directors or shareholders
or other Related Persons, or the Trustee shall be personally or otherwise liable
to any Holder, nor shall the Members, nor any of their respective past, present
or future members, officers, partners, directors or shareholders or other
Related Persons, be personally or otherwise liable to the Trustee for any
amounts payable under any Bond or for any liability under the Indenture or any
other Transaction Document, except as provided in the Original Indenture and (c)
recourse for any such amounts payable shall be otherwise limited in accordance
with Section 2.14 and Section 17.1 of the Original Indenture.

                  The obligations of the Company to pay the principal of and
interest on the Bonds when due as herein prescribed are absolute and
unconditional and no provision of this Bond or the Indenture shall alter or
impair such obligations.

                  The Bonds are subject to a Security Agreement dated as of
February 22, 2000 pursuant to which the rights of the Secured Parties (including
the Holders and the Trustee) in

                                       7
<PAGE>   92

respect of the Collateral will be shared among the Secured Parties and will be
exercised by the Collateral Agent in accordance with the Security Agreement.

                  The Indenture permits, with certain exceptions, as therein
provided, the amendment thereof and the modification of the rights and
obligations of the Company and the rights of the Holder under the Indenture at
any time by the Company with the consent of the Holders of not less than a
majority in aggregate principal amount of the Bonds of all series then
Outstanding. The Indenture also contains provisions permitting the Holders of
specified percentages in aggregate principal amount of the Bonds of all series
then Outstanding, on behalf of the Holders of all the Bonds, to waive compliance
by the Company with certain provisions of the Indenture and certain past
defaults under the Indenture and their consequences. Any Act (as such term is
defined in the Indenture), including, but not limited to, such a consent, waiver
or direction by the Holder of this Bond shall be conclusive and binding upon the
Holder and upon all future Holders of this Bond and the Holder of every Bond
issued upon the transfer hereof or the exchange herefor or in lieu hereof
whether or not notation of such Act is made upon this Bond.

                  This Bond is one of the series designated on the face hereof,
limited to $300,000,000 in aggregate principal amount as provided in the First
Supplemental Indenture.

                  This Bond and all Bonds issued or to be issued in series
created under the First Supplemental Indenture are (i) redeemable at the option
of the Company in accordance with Section 8.2 of the Indenture, on not less than
30 nor more than 60 days' notice, at a redemption price equal to the principal
amount thereof plus unpaid and accrued interest plus the Make-Whole Premium and
(ii) not subject to any sinking fund.

                  The Bonds are, under certain conditions, subject to mandatory
redemption as set forth in Section 8.3 of the Indenture. Notice of any
redemption of Bonds will be given at least 30 days but not more than 60 days
before the Redemption Date to each Holder at its address as it appears in the
Security Register.

                  Bonds (or portions thereof as aforesaid) for the redemption of
which provision is made in accordance with the Indenture shall cease to bear
interest from and after any Redemption Date.

                  The Indenture contains provisions for, upon compliance by the
Company with certain conditions set forth in the Indenture, the defeasance of
(a) the entire indebtedness of this Bond and (b) certain restrictive covenants
and agreements.

                  The unpaid portion of the Principal Amount, together with any
interest accrued and unpaid thereon and all other amounts due hereunder, if any,
may become due and payable upon the occurrence and continuation of any Event of
Default, but only as provided in the Indenture.

                  The Company and the Guarantors have entered into an Exchange
and Registration Rights Agreement dated February 15, 2000 (the "Registration
Rights Agreement") with the Initial Purchasers described therein. Pursuant to
such Registration Rights Agreement, the

                                       8
<PAGE>   93

Company and the Guarantors have agreed to file with the SEC a registration
statement under the Securities Act ("Registration Statement") for an offer to
exchange the Bonds for a like aggregate principal amount of Bonds issued
pursuant to the Indenture that are in all material respects identical to the
Bonds except that such exchange Bonds shall be issued pursuant to an effective
Registration Statement.

                  From and after the date on which a Registration Default (as
defined in the Registration Rights Agreement) occurs, the interest rate payable
on this Bond shall increase (in addition to the interest rate set forth above)
and additional interest reflecting such increase shall accrue with respect to
this Bond, until but not including the date on which such Registration Default
shall cease to exist (and provided no other Registration Default with respect to
this Bond shall then be continuing), at the rate of one half of one percent
(0.50%) per annum, which additional interest shall be payable hereon at the
times, in the manner and subject to the same terms and conditions set forth
herein and in the Indenture, as though the interest rate set forth above had
been increased by one half of one percent (0.50%) per annum.

                  The Bonds are issuable only as registered Bonds without
coupons in minimum denominations of $100,000 and any integral multiple of $1,000
in excess thereof. As provided in, and subject to the provisions of, the
Indenture, Bonds are exchangeable at the option of the Holder thereof for other
Bonds of the same series, of authorized denomination and of like tenor,
maturity, interest rate and aggregate principal amount, to be registered in the
name of such Holder, upon surrender thereof by such Holder at any office or
agency maintained for such purpose pursuant to the Indenture.

                  No service charge will be required of any Holder participating
in any such transfer or exchange of Bonds in respect of such transfer or
exchange, but the Security Registrar may require payment of a sum sufficient to
cover any tax or other governmental charge payable in connection therewith.

                  The person in whose name this Bond is registered shall be
deemed to be the owner and holder hereof for the purpose of receiving payment as
herein provided and for all other purposes whether or not this Bond be overdue
regardless of any notice to anyone to the contrary.

                  Bonds actually known to a Responsible Officer of the Trustee
to be owned or held by, or for the account or benefit of, the Company, the
Guarantors, or an Affiliate of any of the foregoing shall not be entitled to
share in any payment or distribution provided for in Article 10 of the Indenture
until all Bonds held by other Persons have been indefeasibly paid in full.

                  THIS BOND SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE
WITH, THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO PRINCIPLES OF
CONFLICTS OF LAW THEREOF TO THE EXTENT THE APPLICATION OF SUCH PRINCIPLES WOULD
CAUSE THE APPLICATION OF THE LAWS OF ANY OTHER JURISDICTION.

                                       9
<PAGE>   94

                                  ABBREVIATIONS

                  The following abbreviations when used in the inscription on
the face of this instrument shall be construed as though they were written out
in full according to applicable laws or regulations:

         TEN COM  --       as tenants in common
         TEN ENT  --       as tenants by the entireties
          JT TEN  --       as joint tenants with right of
                           survivorship and not as tenants in
                           common

                        UNIF GIFT MIN ACT
                                         ---------------------------------------
                                                      (Cust)  (Minor)

                                         under Uniform Gift to Minors Act

                                         ---------------------------------------

                                                          (State)

                Additional abbreviations may also be used though
                              not in the above list

                               -------------------

                                       10
<PAGE>   95

                  FOR VALUE-RECEIVED the undersigned hereby sell(s), assign(s)
and transfer(s) unto

Social Security Number or Other
Identifying Number of Assignee
                              --------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
                  (Please print or typewrite name and address,
                         including zip code of Assignee)

the within Security and all rights thereunder, hereby irrevocably constituting
and appointing attorney to transfer said Security on the books of the Company,
with full power of substitution in the premises.

Dated:
       ---------------------

                                              ------------------------------
                                              NAME:

NOTICE:           The signature to this assignment must correspond with the name
                  as written upon the first page of the within instrument in
                  every particular, without alteration or enlargement or any
                  change whatsoever.

                                       11
<PAGE>   96
                                                                      ANNEX A TO
                                    9.292% SERIES C SENIOR SECURED BOND DUE 2024

                  The following table sets forth the date of each semiannual
installment of the aggregate principal to be paid on all Bonds of this series on
each such date:

<TABLE>
<CAPTION>
                                                              PRINCIPAL
                                                                 AMOUNT
                        PRINCIPAL                               PAYABLE
                         PAYMENT                              ON SERIES
                          DATES                                 C BONDS
                          -----                                 -------

<S>                <C>                                       <C>
                   December 15, 2015                         $3,000,000
                       June 15, 2016                          3,000,000
                   December 15, 2016                          3,000,000
                       June 15, 2017                          3,500,000
                   December 15, 2017                          3,500,000
                       June 15, 2018                         15,500,000
                   December 15, 2018                         15,500,000
                       June 15, 2019                         17,000,000
                   December 15, 2019                         17,000,000
                       June 15, 2020                         18,500,000
                   December 15, 2020                         18,500,000
                       June 15, 2021                         20,000,000
                   December 15, 2021                         20,000,000
                       June 15, 2022                         22,000,000
                   December 15, 2022                         22,000,000
                       June 15, 2023                         23,000,000
                   December 15, 2023                         23,000,000
                       June 15, 2024                         26,000,000
                   December 15, 2024                         26,000,000
                               TOTAL                       $300,000,000
</TABLE>

                 NRG Northeast Generating Supplemental Indenture

<PAGE>   97

                                                                      ANNEX B TO
                                    9.292% SERIES C SENIOR SECURED BOND DUE 2024

        Exchanges of portions of this Global Bond for definitive Bonds:

<TABLE>
<CAPTION>
=====================================================================================================================
                         PRINCIPAL AMOUNT OF DEFINITIVE
                         SECURITIES ISSUED IN EXCHANGE FOR A   REMAINING PRINCIPAL AMOUNT
DATE                     PORTION OF THIS GLOBAL SECURITY       OF THIS GLOBAL SECURITY        NOTATION MADE BY
------------------------ ------------------------------------- ------------------------------ ----------------------
<S>                      <C>                                   <C>                            <C>

------------------------ ------------------------------------- ------------------------------ ----------------------

------------------------ ------------------------------------- ------------------------------ ----------------------

------------------------ ------------------------------------- ------------------------------ ----------------------

------------------------ ------------------------------------- ------------------------------ ----------------------

------------------------ ------------------------------------- ------------------------------ ----------------------

------------------------ ------------------------------------- ------------------------------ ----------------------

------------------------ ------------------------------------- ------------------------------ ----------------------

=====================================================================================================================
</TABLE>

                 NRG Northeast Generating Supplemental Indenture

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