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                                                                EXHIBIT 4.9

                                                                EXECUTION COPY

                          NRG NORTHEAST GENERATING LLC

                                      and

                     the Subsidiary Guarantors party hereto

           $320,000,000 8.065% Series A Senior Secured Bonds due 2004
           $130,000,000 8.842% Series B Senior Secured Bonds due 2015
           $300,000,000 9.292% Series C Senior Secured Bonds due 2024

                   EXCHANGE AND REGISTRATION RIGHTS AGREEMENT

                                                      February, 15 2000

CHASE SECURITIES INC.
SALOMON SMITH BARNEY INC.
     On behalf of the Initial Purchasers
     Named in Schedule 1 hereto

Ladies and Gentlemen:

                  NRG Northeast Generating LLC, a Delaware limited liability
company (the "Company"), proposes to issue and sell to the Initial Purchasers
named in Schedule 1 hereto (the "Initial Purchasers"), upon the terms and
subject to the conditions set forth in a purchase agreement dated February 15,
2000 (the "Purchase Agreement"), between the Company and the Initial
Purchasers, $320,000,000 aggregate principal amount of its 8.065% Series A
Senior Secured Bonds due 2004, $130,000,000 aggregate principal amount of its
8.842% Series B Senior Secured Bonds due 2015 and $300,000,000 aggregate
principal amount of its 9.292% Series C Senior Secured Bonds due 2024 (the
"Securities"). Capitalized terms used but not defined herein shall have the
meanings given to such terms in the Purchase Agreement.

                  As an inducement to the Initial Purchasers to enter into the
Purchase Agreement and in satisfaction of a condition to the obligations of the
Initial Purchasers thereunder, the Company and each Guarantor (together with
the Company, the "Registrants") agrees with the Initial Purchasers, for the
benefit of the holders (including the Initial Purchasers) of the Securities,
the Exchange Securities (as defined herein) and the Private Exchange Securities
(as defined herein) (collectively, the "Holders"), as follows:




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                  1. Registered Exchange Offer. The Registrants shall use their
reasonable best efforts to (i) prepare and file with the Commission a
registration statement (the "Exchange Offer Registration Statement") on an
appropriate form under the Securities Act with respect to a proposed offer to
the Holders of the Securities (the "Registered Exchange Offer") to issue and
deliver to such Holders, in exchange for the Securities, a like aggregate
principal amount of debt securities of the Company guaranteed by the Guarantors
(the "Exchange Securities") that are identical in all material respects to the
Securities, except for the transfer restrictions relating to the Securities and
the rights relating to this Agreement, (ii) use their reasonable best efforts
to cause the Exchange Offer Registration Statement to become effective under
the Securities Act no later than 270 days following the date of original
issuance of the Securities (the "Issue Date") and (iii) keep the Exchange Offer
Registration Statement effective for not less than 30 days (or longer, if
required by applicable law) after the date on which notice of the Registered
Exchange Offer is mailed to the Holders (such period being called the "Exchange
Offer Registration Period"). The Exchange Securities will be issued under the
Indenture or an indenture (the "Exchange Securities Indenture") between the
Registrants and the Trustee or such other bank or trust company that is
reasonably satisfactory to the Initial Purchasers, as trustee (the "Exchange
Securities Trustee").

                  Upon the effectiveness of the Exchange Offer Registration
Statement, the Registrants shall promptly commence the Registered Exchange
Offer, it being the objective of such Registered Exchange Offer to enable each
Holder electing to exchange Securities for Exchange Securities (assuming that
such Holder (a) is not an affiliate (as defined in Section 10(e) below) of any
of the Registrants or of an Exchanging Dealer (as defined herein) not complying
with the requirements of the next sentence, (b) is not an Initial Purchaser
holding Securities that have, or that are reasonably likely to have, the status
of an unsold allotment in an initial distribution, (c) acquires the Exchange
Securities in the ordinary course of such Holder's business and (d) has no
arrangements or understandings with any person to participate in the
distribution of the Exchange Securities) and to trade such Exchange Securities
from and after their receipt without any limitations or restrictions under the
Securities Act and without material restrictions under the securities laws of
the several states of the United States. The Registrants, the Initial
Purchasers and each Exchanging Dealer acknowledge that, pursuant to current
interpretations by the Commission's staff of Section 5 of the Securities Act,
each Holder that is a broker-dealer electing to exchange Securities, acquired
for its own account as a result of market-making activities or other trading
activities, for Exchange Securities (an "Exchanging Dealer"), is required to
deliver a prospectus containing substantially the information set forth in
Annex A hereto on the cover, in Annex B hereto in the "Exchange Offer
Procedures" section and the "Purpose of the Exchange Offer" section and in
Annex C hereto in the "Plan of Distribution" section of such prospectus in
connection with a sale of any such Exchange Securities received by such
Exchanging Dealer pursuant to the Registered Exchange Offer.

         If, prior to the consummation of the Registered Exchange Offer, any
Holder holds any Securities acquired by it that have, or that are reasonably
likely to be determined to have, the status of an unsold allotment in an
initial distribution, or any Holder is not entitled to participate in the
Registered Exchange Offer, the Company shall, upon the request of any such
Holder, simultaneously with the delivery of the Exchange Securities in the
Registered Exchange Offer, issue and deliver to any such Holder, in exchange
for the Securities held by such Holder (the "Private Exchange"), a like
aggregate principal amount of debt securities of the Company guaranteed by the
Guarantors (the "Private Exchange Securities") that are identical in all
material respects to the



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Exchange Securities, except for the transfer restrictions relating to such
Private Exchange Securities. The Private Exchange Securities will be issued
under the same Indenture as the Exchange Securities, and the Registrants shall
use their reasonable best efforts to cause the Private Exchange Securities to
bear the same CUSIP number as the Exchange Securities, upon resale of the
Private Exchange Securities pursuant to a registration statement declared by
the Commission.

                  In connection with the Registered Exchange Offer, the
Registrants shall:

                  (a)       mail to each Holder a copy of the prospectus
         forming part of the Exchange Offer Registration Statement, together
         with an appropriate letter of transmittal and related documents;

                  (b)       keep the Registered Exchange Offer open for not
         less than 30 days (or longer, if required by applicable law) after the
         date on which notice of the Registered Exchange Offer is mailed to the
         Holders;

                  (c)       utilize the services of a depositary for the
         Registered Exchange Offer with an address in the Borough of Manhattan,
         The City of New York;

                  (d)       permit Holders to withdraw tendered Securities at
         any time prior to the close of business, New York City time, on the
         last business day on which the Registered Exchange Offer shall remain
         open; and

                  (e)       otherwise comply in all respects with all laws that
         are applicable to the Registered Exchange Offer.

                  As soon as practicable after the close of the Registered
Exchange Offer and any Private Exchange, as the case may be, the Registrants
shall:

                  (a)       accept for exchange all Securities properly
         tendered and not validly withdrawn pursuant to the Registered Exchange
         Offer and the Private Exchange;

                  (b)       deliver to the Trustee for cancellation all
         Securities so accepted for exchange; and

                  (c)       cause the Trustee or the Exchange Securities
         Trustee, as the case may be, promptly to authenticate and deliver to
         each Holder who has properly tendered, Exchange Securities or Private
         Exchange Securities, as the case may be, equal in principal amount to
         the Securities of such Holder so accepted for exchange.

                  The Registrants shall use their reasonable best efforts to
keep the Exchange Offer Registration Statement effective and to amend and
supplement the prospectus contained therein in order to permit such prospectus
to be used by all persons subject to the prospectus delivery requirements of
the Securities Act for such period of time as such persons must comply with
such requirements in order to resell the Exchange Securities; provided that (i)
in the case where such prospectus and any amendment or supplement thereto must
be delivered by an Exchanging Dealer,



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such period shall end on the earlier of 90 days from the date of the
consummation of the Exchange Offer and the date on which all Exchanging Dealers
have sold all Exchange Securities held by them and (ii) the Registrants shall
make such prospectus and any amendment or supplement thereto available to any
broker-dealer for use in connection with any resale of any Exchange Securities
for a period of not less than 90 days after the consummation of the Registered
Exchange Offer.

                  The Indenture or the Exchange Securities Indenture, as the
case may be, shall provide that the Securities, the Exchange Securities and the
Private Exchange Securities shall vote and consent together on all matters as
one class and that none of the Securities, the Exchange Securities or the
Private Exchange Securities will have the right to vote or consent as a
separate class on any matter.

                  Interest on each Exchange Security and Private Exchange
Security issued pursuant to the Registered Exchange Offer and in the Private
Exchange will accrue from the last interest payment date on which interest was
paid on the Securities surrendered in exchange therefor or, if no interest has
been paid on the Securities, from the Issue Date.

                  Each Holder participating in the Registered Exchange Offer
shall be required to represent to the Company that at the time of the
consummation of the Registered Exchange Offer (i) any Exchange Securities
received by such Holder will be acquired in the ordinary course of business,
(ii) such Holder will have no arrangements or understanding with any person to
participate in the distribution of the Securities or the Exchange Securities
within the meaning of the Securities Act and (iii) such Holder is not an
affiliate of the Registrants or, if it is such an affiliate, such Holder will
comply with the registration and prospectus delivery requirements of the
Securities Act to the extent applicable.

                  Notwithstanding any other provisions hereof, the Registrants
will ensure that (i) any Exchange Offer Registration Statement and any
amendment thereto and any prospectus forming part thereof and any supplement
thereto complies in all material respects with the Securities Act and the rules
and regulations of the Commission thereunder, (ii) any Exchange Offer
Registration Statement and any amendment thereto does not, when it becomes
effective, contain an untrue statement of a material fact or omit to state a
material fact required to be stated therein or necessary to make the statements
therein not misleading and (iii) any prospectus forming part of any Exchange
Offer Registration Statement, and any supplement to such prospectus, does not,
as of the consummation of the Registered Exchange Offer, include an untrue
statement of a material fact or omit to state a material fact necessary in
order to make the statements therein, in the light of the circumstances under
which they were made, not misleading.

                  2. Shelf Registration. If (i) because of any change in law or
applicable interpretations thereof by the Commission's staff the Registrants
are not permitted to effect the Registered Exchange Offer as contemplated by
Section 1 hereof, or (ii) any Securities validly tendered pursuant to the
Registered Exchange Offer are not exchanged for Exchange Securities within 315
days after the Issue Date (unless the Exchange Offer is still in process), or
(iii) any Initial Purchaser so requests with respect to Securities or Private
Exchange Securities not eligible to be exchanged for Exchange Securities in the
Registered Exchange Offer and held by it following the consummation of the
Registered Exchange Offer, or (iv) any applicable law or interpretations do



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not permit any Holder (other than an Initial Purchaser) to participate in the
Registered Exchange Offer or (v) any Holder (other than an Initial Purchaser)
that participates in the Registered Exchange Offer does not receive freely
transferable Exchange Securities in exchange for tendered Securities, or (vi)
the Company so elects, then the following provisions shall apply:

                  (a)       The Registrants shall use their reasonable best
efforts to file as promptly as practicable with the Commission, and thereafter
shall use their reasonable best efforts to cause to be declared effective, a
shelf registration statement on an appropriate form under the Securities Act
relating to the offer and sale of the Transfer Restricted Securities (as
defined below) by the Holders thereof from time to time in accordance with the
methods of distribution set forth in such registration statement (hereafter, a
"Shelf Registration Statement" and, together with any Exchange Offer
Registration Statement, a "Registration Statement").

                  (b)       The Registrants shall use their reasonable best
efforts to keep the Shelf Registration Statement continuously effective in
order to permit the prospectus forming part thereof to be used by Holders of
Transfer Restricted Securities for a period ending on the earlier of (i) two
years from the Issue Date or such shorter period that will terminate when all
the Transfer Restricted Securities covered by the Shelf Registration Statement
have been sold pursuant thereto and (ii) the date on which the Securities
become eligible for resale without volume restrictions pursuant to Rule 144
under the Securities Act (in any such case, such period being called the "Shelf
Registration Period"); provided that with respect to Exchange Securities
received by an Initial Purchaser in exchange for Securities constituting any
portion of an unsold allotment, the Company may, if permitted by current
interpretations by the Commission's staff, file a post-effective amendment to
the Exchange Offer Registration Statement containing the information required
by Regulation S-K Items 507 and/or 508, as applicable, in satisfaction of its
obligations under this Section 2 with respect thereto, and any such Exchange
Offer Registration Statement, as so amended shall be referred to herein as, and
governed by the provisions herein applicable to, a Shelf Registration
Statement. The Registrants shall be deemed not to have used their reasonable
best efforts to keep the Shelf Registration Statement effective during the
requisite period if they voluntarily take any action that would result in
Holders of Transfer Restricted Securities covered thereby not being able to
offer and sell such Transfer Restricted Securities during that period, unless
such action is (i) required by applicable law or (ii) such action is taken by
the Company in good faith and for valid business reasons, including the
acquisition or divestiture of assets.

                  (c)       Notwithstanding any other provisions hereof, the
Registrants will ensure that (i) any Shelf Registration Statement and any
amendment thereto and any prospectus forming part thereof and any supplement
thereto complies in all material respects with the Securities Act and the rules
and regulations of the Commission thereunder, (ii) any Shelf Registration
Statement and any amendment thereto (in either case, other than with respect to
information included therein in reliance upon or in conformity with written
information furnished to the Registrants by or on behalf of any Holder
specifically for use therein (the "Holders' Information")) does not, when it
becomes effective, contain an untrue statement of a material fact or omit to
state a material fact required to be stated therein or necessary to make the
statements therein not misleading and (iii) any prospectus forming part of any
Shelf Registration Statement, and any supplement to such prospectus (in either
case, other than with respect to



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Holders' Information), does not include an untrue statement of a material fact
or omit to state a material fact necessary in order to make the statements
therein, in the light of the circumstances under which they were made, not
misleading.

                  3. Liquidated Damages. (a) The parties hereto agree that the
Holders of Transfer Restricted Securities will suffer damages if the
Registrants fail to fulfill their obligations under Section 1 or Section 2, as
applicable, and that it would not be feasible to ascertain the extent of such
damages. Accordingly, if (i) the Registered Exchange Offer is not consummated
on or prior to 315 days (or if the 315th day is not a business day, the next
business day following the 315th day) after the Issue Date or (ii) the Exchange
Offer Registration Statement or the Shelf Registration Statement, as the case
may be, is not declared effective within 270 days (or, if the 270th day is not
a business day, the next business day following the 270th day) after the Issue
Date (or in the case of a Shelf Registration Statement required to be filed in
response to a change in law or the applicable interpretations of the
Commission's staff, if later, within 45 days (or if the 45th day is not a
business day, the next business day following the 45th day) after publication
of the change in law or interpretation), (iii) the Shelf Registration Statement
is filed and declared effective within 270 days after the Issue Date (or in the
case of a Shelf Registration Statement required to be filed in response to a
change in law or the applicable interpretations of Commission's staff, if
later, within 45 days after publication of the change in law or interpretation)
but shall thereafter cease to be effective or usable (at any time that the
Registrants are obligated to maintain the effectiveness thereof) without being
succeeded within 30 days by an additional Registration Statement filed and
declared effective (each such event referred to in clauses (i) through (iii), a
"Registration Default"), the Registrants will be obligated to pay liquidated
damages to each Holder of Transfer Restricted Securities, during the period of
one or more such Registration Defaults, in the form of additional interest (in
addition to the interest otherwise payable with respect to the Transfer
Restricted Securities) at a rate of one half of one percent (0.50%) per annum,
which additional interest shall be payable by the Registrants to each Holder of
Transfer Restricted Securities at the time, in the manner and subject to the
same terms and conditions set forth in the Indenture and the Bonds, until (i)
the Exchange Offer Registration Statement is declared effective and/or the
Registered Exchange Offer is consummated, (ii) the Shelf Registration Statement
is declared effective or (iii) the Shelf Registration Statement again becomes
effective, as the case may be. Following the cure of all Registration Defaults,
the accrual of liquidated damages will cease. As used herein, the term
"Transfer Restricted Securities" means (i) each Security until the date on
which such Security has been exchanged for a freely transferable Exchange
Security in the Registered Exchange Offer, (ii) each Security or Private
Exchange Security until the date on which it has been effectively registered
under the Securities Act and disposed of in accordance with the Shelf
Registration Statement or (iii) each Security or Private Exchange Security
until the date on which it is distributed to the public pursuant to Rule 144
under the Securities Act or is saleable pursuant to Rule 144(k) under the
Securities Act. Notwithstanding anything to the contrary in this Section 3(a),
the Registrants shall not be required to pay liquidated damages to a Holder of
Transfer Restricted Securities if such Holder failed to comply with its
obligations to make the representations set forth in the second to last
paragraph of Section 1, failed to provide the information required to be
provided by it, if any, pursuant to Section 4(n) or failed to properly tender
Securities for Exchange Securities in the Exchange Offer.

                  (b)       The Registrants shall notify the Trustee and the
Paying Agent under the Indenture immediately upon the happening of each and
every Registration Default. The


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Registrants shall pay the liquidated damages due on the Transfer Restricted
Securities by depositing with the Paying Agent (which may not be the Company
for these purposes), in trust, for the benefit of the Holders thereof, prior to
10:00 a.m., New York City time, on the next interest payment date specified by
the Indenture and the Securities, sums sufficient to pay the liquidated damages
then due. The liquidated damages due shall be payable on each interest payment
date specified by the Indenture and the Securities to the record holder
entitled to receive the interest payment to be made on such date. Each
obligation to pay liquidated damages shall be deemed to accrue from and
including the date of the applicable Registration Default.

                  (c)       The parties hereto agree that the liquidated
damages provided for in this Section 3 constitute a reasonable estimate of and
are intended to constitute the sole damages that will be suffered by Holders of
Transfer Restricted Securities by reason of the failure of (i) the Shelf
Registration Statement to become or remain effective or (ii) the Exchange Offer
Registration Statement to be declared effective and/or the Registered Exchange
Offer to be consummated, in each case to the extent required by this Agreement.

                  4.  Registration Procedures.  In connection with any
Registration Statement, the following provisions shall apply:

                  (a)       The Registrants shall (i) furnish to each Initial
Purchaser, prior to the filing thereof with the Commission, a copy of the
Registration Statement and each amendment thereof and each supplement, if any,
to the prospectus included therein and shall use their reasonable best efforts
to reflect in each such document, when so filed with the Commission, such
comments as any Initial Purchaser may reasonably propose; (ii) include
information substantially similar to that set forth in Annex A hereto on the
cover, in Annex B hereto in the "Exchange Offer Procedures" section and the
"Purpose of the Exchange Offer" section and in Annex C hereto in the "Plan of
Distribution" section of the prospectus forming a part of the Exchange Offer
Registration Statement, and include information substantially similar to that
set forth in Annex D hereto in the Letter of Transmittal delivered pursuant to
the Registered Exchange Offer; and (iii) if requested by any Initial Purchaser,
include the information required by Items 507 or 508 of Regulation S-K, as
applicable, in the prospectus forming a part of the Exchange Offer Registration
Statement.

                  (b)       The Registrants shall advise each Initial
Purchaser, each Exchanging Dealer which has identified itself to the Company
and provided the Company a facsimile number or address for notices and the
Holders (if applicable in the case of a Shelf Registration Statement) and, if
requested by any such person, confirm such advice in writing (which, if after
the effectiveness of the Registration Statement, advice pursuant to clauses
(ii)-(v) hereof shall be accompanied by an instruction to suspend the use of
the prospectus until the requisite changes have been made):

                  (i)       when any Registration Statement and any amendment
thereto has been filed with the Commission and when such Registration Statement
or any post-effective amendment thereto has become effective;

                  (ii)      of any request by the Commission for amendments or
supplements to any



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Registration Statement or the prospectus included therein or for additional
information;

                  (iii)     of the issuance by the Commission of any stop order
suspending the effectiveness of any Registration Statement or the initiation of
any proceedings for that purpose;

                  (iv)      of the receipt by the any of the Registrants of any
notification with respect to the suspension of the qualification of the
Securities, the Exchange Securities or the Private Exchange Securities which
are registered pursuant to such Registration Statement for sale in any
jurisdiction or the initiation or threatening of any proceeding for such
purpose; and

                  (v)       of the happening of any event that requires the
making of any changes in any Registration Statement or the prospectus included
therein in order that the statements therein, in the case of the prospectus, in
light of the circumstances under which they were made, are not misleading and
do not omit to state a material fact required to be stated therein or necessary
to make the statements therein, in the case of the prospectus, in light of the
circumstances under which they were made, not misleading.

                  (c)       Subject to the last sentence of Section 2(b), the
Registrants will use its reasonable best efforts to obtain the withdrawal at
the earliest possible time of any order suspending the effectiveness of any
Registration Statement.

                  (d)       The Registrants will furnish to each Holder of
Transfer Restricted Securities included within the coverage of any Shelf
Registration Statement, without charge, at least one conformed copy of such
Shelf Registration Statement and any post-effective amendment thereto,
including financial statements and schedules and, if any such Holder so
requests in writing, all exhibits thereto (including those, if any,
incorporated by reference).

                  (e)       The Registrants will, during the Shelf Registration
Period, promptly deliver to each Holder of Transfer Restricted Securities
included within the coverage of any Shelf Registration Statement, without
charge, as many copies of the prospectus (including each preliminary
prospectus) included in such Shelf Registration Statement and any amendment or
supplement thereto as such Holder may reasonably request; and the Registrants
consent to the use of such prospectus or any amendment or supplement thereto by
each of the selling Holders of Transfer Restricted Securities in connection
with the offer and sale of the Transfer Restricted Securities covered by such
prospectus or any amendment or supplement thereto.

                  (f)       The Registrants will furnish to each Initial
Purchaser and each Exchanging Dealer, without charge, at least one conformed
copy of the Exchange Offer Registration Statement and any post-effective
amendment thereto, including financial statements and schedules and, if any
Initial Purchaser or Exchanging Dealer so requests in writing, all exhibits
thereto (including those, if any, incorporated by reference).

                  (g)       The Registrants will, during the Exchange Offer
Registration Period or the Shelf Registration Period, as applicable, promptly
deliver to each Initial Purchaser, each Exchanging Dealer and such other
persons that are required by law to deliver a prospectus following the
Registered Exchange Offer, or during the Shelf Registration Period, as
applicable,



                  NRG Northeast Registration Rights Agreement


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without charge, as many copies of the final prospectus included in the Exchange
Offer Registration Statement or the Shelf Registration Statement and any
amendment or supplement thereto as such Initial Purchaser, Exchanging Dealer or
other persons may reasonably request; and the Registrants consent to the use of
such prospectus or any amendment or supplement thereto by any such Initial
Purchaser, Exchanging Dealer or other persons, as applicable, as aforesaid.

                  (h)       Prior to the effective date of any Registration
Statement, the Registrants will use their reasonable best efforts to cooperate
with the Holders of Securities, Exchange Securities or Private Exchange
Securities included therein and their respective counsel in connection with the
registration or qualification of, such Securities, Exchange Securities or
Private Exchange Securities for offer and sale under the securities or blue sky
laws of such jurisdictions as any such Holder reasonably requests in writing
and do any and all other acts or things necessary to enable the offer and sale
in such jurisdictions of the Securities, Exchange Securities or Private
Exchange Securities covered by such Registration Statement; provided that the
Registrants will not be required to qualify generally to do business in any
jurisdiction where it is not then so qualified or to take any action which
would subject it to general service of process or to taxation in any such
jurisdiction where it is not then so subject.

                  (i)       Unless the applicable securities shall be in
book-entry only form, the Registrants will cooperate with the Holders of
Securities, Exchange Securities or Private Exchange Securities to facilitate
the timely preparation and delivery of certificates representing Securities,
Exchange Securities or Private Exchange Securities issued or sold pursuant to
any Registration Statement free of any restrictive legends and in such
denominations and registered in such names as the Holders thereof may request
in writing prior to sales of Securities, Exchange Securities or Private
Exchange Securities pursuant to such Registration Statement.

                  (j)       Subject to the last sentence of Section 2(b), after
effectiveness of a Registration Statement, if any event contemplated by Section
4(b)(ii) through (v) occurs during the period for which the Registrants are
required to maintain the effectiveness of such Registration Statement, the
Registrants will promptly prepare and file with the Commission a post-effective
amendment to the Registration Statement or a supplement to the related
prospectus or file any other required document so that, as thereafter delivered
to purchasers of the Securities, Exchange Securities or Private Exchange
Securities from a Holder, the prospectus will not include an untrue statement
of a material fact or omit to state a material fact necessary in order to make
the statements therein, in the light of the circumstances under which they were
made, not misleading.

                  (k)       Not later than the effective date of the applicable
Registration Statement, the Registrants will provide a CUSIP number for the
Securities, the Exchange Securities and the Private Exchange Securities, as the
case may be, and provide the applicable trustee with printed certificates for
the Securities, the Exchange Securities or the Private Exchange Securities, as
the case may be, in a form eligible for deposit with The Depository Trust
Company.

                  (l)       The Company will comply with all applicable rules
and regulations of the Commission and will make generally available to its
security holders as soon as practicable after


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                                       -10-

the effective date of the applicable Registration Statement an earning
statement satisfying the provisions of Section 11(a) of the Securities Act.

                  (m)       The Registrants will cause the Indenture or the
Exchange Securities Indenture, as applicable, to be qualified under the Trust
Indenture Act as required by applicable law in a timely manner.

                  (n)       The Company may require each Holder of Transfer
Restricted Securities to be registered pursuant to any Shelf Registration
Statement to furnish to the Company such information concerning the Holder and
the distribution of such Transfer Restricted Securities as the Registrants may
from time to time reasonably require for inclusion in such Shelf Registration
Statement, and the Company may exclude from such registration the Transfer
Restricted Securities of any Holder that fails to furnish such information
within a reasonable time after receiving such request.

                  (o)       In the case of a Shelf Registration Statement, each
Holder of Transfer Restricted Securities to be registered pursuant thereto
agrees that, upon receipt of any notice from the Registrants pursuant to
Section 4(b)(ii) through (v), such Holder will discontinue disposition of such
Transfer Restricted Securities until such Holder's receipt of copies of the
supplemental or amended prospectus contemplated by Section 4(j) or until
advised in writing (the "Advice") by the Company that the use of the applicable
prospectus may be resumed. If the Registrants shall give any notice under
Section 4(b)(ii) through (v) during the period that the Registrants are
required to maintain an effective Registration Statement (the "Effectiveness
Period"), such Effectiveness Period shall be extended by the number of days
during such period from and including the date of the giving of such notice to
and including the date when each seller of Transfer Restricted Securities
covered by such Registration Statement shall have received (x) the copies of
the supplemental or amended prospectus contemplated by Section 4(j) (if an
amended or supplemental prospectus is required) or (y) the Advice (if no
amended or supplemental prospectus is required).

                  (p)       In the case of a Shelf Registration Statement, the
Registrants shall enter into such customary agreements (including, if
requested, an underwriting agreement in customary form) and take all such other
action, if any, as Holders of a majority in aggregate principal amount of the
Securities, Exchange Securities and Private Exchange Securities being sold or
the managing underwriters (if any) shall reasonably request in order to
facilitate any disposition of Securities, Exchange Securities or Private
Exchange Securities pursuant to such Shelf Registration Statement.

                  (q)       In the case of a Shelf Registration Statement, the
Registrants shall (i) make reasonably available for inspection by a
representative of, and Special Counsel (as defined below) acting for, Holders
of a majority in aggregate principal amount of the Securities, Exchange
Securities and Private Exchange Securities being sold pursuant to such Shelf
Registration Statement and any underwriter participating in any disposition of
Securities, Exchange Securities or Private Exchange Securities pursuant to such
Shelf Registration Statement, all relevant financial and other records,
pertinent corporate documents and properties of the Registrants and their
subsidiaries and (ii) use its reasonable best efforts to have its officers,




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                                       -11-

directors, employees, accountants and counsel supply all relevant information
reasonably requested by such representative, Special Counsel or any such
underwriter (an "Inspector") in connection with such Shelf Registration
Statement; provided, however, that any information that is designated in
writing by the Company, in good faith, as confidential at the time of delivery
of such information shall be kept confidential by the Holders or any such
Inspector.

                  (r)       In the case of a Shelf Registration Statement, the
Registrants shall, if requested by Holders of a majority in aggregate principal
amount of the Securities, Exchange Securities and Private Exchange Securities
being sold pursuant to such Shelf Registration Statement, their Special Counsel
or the managing underwriters (if any) in connection with such Shelf
Registration Statement, use their reasonable best efforts to cause (i) their
counsel to deliver an opinion relating to the Shelf Registration Statement and
the Securities, Exchange Securities or Private Exchange Securities being
registered, as applicable, in customary form, (ii) their officers to execute
and deliver all customary documents and certificates reasonably requested by
Holders of a majority in aggregate principal amount of the Securities, Exchange
Securities and Private Exchange Securities being sold pursuant to such Shelf
Registration Statement, their Special Counsel or the managing underwriters (if
any) and (iii) their independent public accountants to provide a comfort letter
or letters in customary form, subject to receipt of appropriate documentation
as contemplated, and only if permitted, by Statement of Auditing Standards No.
72.

                  5. Registration Expenses. The Registrants will bear all
expenses incurred in connection with the performance of their obligations under
Sections 1, 2, 3 and 4 and the Registrants will reimburse the Initial
Purchasers and the Holders for the reasonable fees and disbursements of one
firm of attorneys chosen by the Holders of a majority in aggregate principal
amount of the Securities, the Exchange Securities and the Private Exchange
Securities to be sold pursuant to a Shelf Registration Statement (the "Special
Counsel") acting for the Initial Purchasers or Holders in connection therewith.

                  6. Indemnification. (a) In the event of a Shelf Registration
Statement or in connection with any prospectus delivery pursuant to an Exchange
Offer Registration Statement by an Initial Purchaser or Exchanging Dealer, as
applicable, the Registrants shall indemnify and hold harmless each Holder
(including, without limitation, any such Initial Purchaser or Exchanging
Dealer), its affiliates, their respective officers, directors, employees,
representatives and agents, and each person, if any, who controls such Holder
within the meaning of the Securities Act or the Exchange Act (collectively
referred to for purposes of this Section 6 and Section 7 as a Holder) from and
against any loss, claim, damage or liability, joint or several, or any action
in respect thereof (including, without limitation, any loss, claim, damage,
liability or action relating to purchases and sales of Securities, Exchange
Securities or Private Exchange Securities), to which that Holder may become
subject, whether commenced or threatened, under the Securities Act, the
Exchange Act, any other federal or state statutory law or regulation, at common
law or otherwise, insofar as such loss, claim, damage, liability or action
arises out of, or is based upon, (i) any untrue statement or alleged untrue
statement of a material fact contained in any such Registration Statement or
any prospectus forming part thereof or in any amendment or supplement thereto
or (ii) the omission or alleged omission to state therein a material fact
required to be stated therein or necessary in order to make the statements
therein, in the light of the circumstances under which they



                  NRG Northeast Registration Rights Agreement


<PAGE>   12


                                       -12-

were made, not misleading, and shall reimburse each Holder promptly upon demand
for any legal or other expenses reasonably incurred by that Holder in
connection with investigating or defending or preparing to defend against or
appearing as a third party witness in connection with any such loss, claim,
damage, liability or action as such expenses are incurred; provided, however,
that the Registrants shall not be liable in any such case to the extent that
any such loss, claim, damage, liability or action arises out of, or is based
upon, an untrue statement or alleged untrue statement in or omission or alleged
omission from any of such documents in reliance upon and in conformity with any
Holders' Information; and provided, further, that with respect to any such
untrue statement in or omission from any related prospectus, the indemnity
agreement contained in this Section 6(a) shall not inure to the benefit of any
Holder from whom the person asserting any such loss, claim, damage, liability
or action received Securities, Exchange Securities or Private Exchange
Securities to the extent that such loss, claim, damage, liability or action of
or with respect to such Holder results from the fact that both (A) a copy of
the final prospectus or any amendment or supplement thereto was not sent or
given to such person at or prior to the written confirmation of the sale of
such Securities, Exchange Securities or Private Exchange Securities to such
person and (B) the untrue statement in or omission from the related prospectus
was corrected in such final prospectus as so amended or supplemented unless, in
either case, such failure to deliver such final prospectus as so amended of
supplemented was a result of non-compliance by the Registrants with Section
4(e) or 4(g).

                  (b)       In the event of a Shelf Registration Statement or
in connection with any prospectus delivered pursuant to an Exchange Offer
Registration Statement by an Initial Purchaser of an Exchanging Dealer, each
Holder or such Initial Purchaser or Exchanging Dealer shall indemnify and hold
harmless the Registrants, their affiliates, their respective officers,
directors, employees, representatives and agents, and each person, if any, who
controls the Registrants within the meaning of the Securities Act or the
Exchange Act (collectively referred to for purposes of this Section 6(b) and
Section 7 as the Company), from and against any loss, claim, damage or
liability, joint or several, or any action in respect thereof, to which the
Registrants may become subject, whether commenced or threatened, under the
Securities Act, the Exchange Act, any other federal or state statutory law or
regulation, at common law or otherwise, insofar as such loss, claim, damage,
liability or action arises out of, or is based upon, (i) any untrue statement
or alleged untrue statement of a material fact contained in any such
Registration Statement or any prospectus forming part thereof or in any
amendment or supplement thereto or (ii) the omission or alleged omission to
state therein a material fact required to be stated therein or necessary in
order to make the statements therein, in the light of the circumstances under
which they were made, not misleading, but in each case only to the extent that
the untrue statement or alleged untrue statement or omission or alleged
omission was made in reliance upon and in conformity with, in the case of any
Holder, any Holders' Information furnished to the Registrants by such Holder
and, in the case of an Initial Purchaser or Exchanging Dealer, any information
furnished to the Registrants by any Initial Purchaser or Exchanging Dealer for
use in the Exchange Offer Registration Statement, and shall reimburse the
Registrants for any legal or other expenses reasonably incurred by the
Registrants in connection with investigating or defending or preparing to
defend against or appearing as a third party witness in connection with any
such loss, claim, damage, liability or action as such expenses are incurred;
provided, however, that no such Holder shall be liable for any indemnity claims
hereunder in excess of the amount of net proceeds received by such Holder from
the sale of



                  NRG Northeast Registration Rights Agreement


<PAGE>   13


                                       -13-

Securities, Exchange Securities or Private Exchange Securities pursuant to such
Shelf Registration Statement.

                  (c)       Promptly after receipt by an indemnified party
under this Section 6 of notice of any claim or the commencement of any action,
the indemnified party shall, if a claim in respect thereof is to be made
against the indemnifying party pursuant to Section 6(a) or 6(b), notify the
indemnifying party in writing of the claim or the commencement of that action;
provided, however, that the failure to notify the indemnifying party shall not
relieve it from any liability which it may have under this Section 6 except to
the extent that it has been materially prejudiced (through the forfeiture of
substantive rights or defenses) by such failure; and provided, further, that
the failure to notify the indemnifying party shall not relieve it from any
liability which it may have to an indemnified party otherwise than under this
Section 6. If any such claim or action shall be brought against an indemnified
party, and it shall notify the indemnifying party thereof, the indemnifying
party shall be entitled to participate therein and, to the extent that it
wishes, jointly with any other similarly notified indemnifying party, to assume
the defense thereof with counsel reasonably satisfactory to the indemnified
party. After notice from the indemnifying party to the indemnified party of its
election to assume the defense of such claim or action, the indemnifying party
shall not be liable to the indemnified party under this Section 6 for any legal
or other expenses subsequently incurred by the indemnified party in connection
with the defense thereof other than the reasonable costs of investigation;
provided, however, that an indemnified party shall have the right to employ its
own counsel in any such action, but the fees, expenses and other charges of
such counsel for the indemnified party will be at the expense of such
indemnified party unless (1) the employment of counsel by the indemnified party
has been authorized in writing by the indemnifying party, (2) the indemnified
party has reasonably concluded (based upon advice of counsel to the indemnified
party) that there may be legal defenses available to it or other indemnified
parties that are different from or in addition to those available to the
indemnifying party, (3) a conflict or potential conflict exists (based upon
advice of counsel to the indemnified party) between the indemnified party and
the indemnifying party (in which case the indemnifying party will not have the
right to direct the defense of such action on behalf of the indemnified party)
or (4) the indemnifying party has not in fact employed counsel reasonably
satisfactory to the indemnified party to assume the defense of such action
within a reasonable time after receiving notice of the commencement of the
action, in each of which cases the reasonable fees, disbursements and other
charges of counsel will be at the expense of the indemnifying party or parties.
It is understood that the indemnifying party or parties shall not, in
connection with any proceeding or related proceedings in the same jurisdiction,
be liable for the reasonable fees, disbursements and other charges of more than
one separate firm of attorneys (in addition to any local counsel) at any one
time for all such indemnified party or parties. Each indemnified party, as a
condition of the indemnity agreements contained in Sections 6(a) and 6(b),
shall use all reasonable efforts to cooperate with the indemnifying party in
the defense of any such action or claim. No indemnifying party shall be liable
for any settlement of any such action effected without its written consent, but
if settled with its written consent or if there be a final judgment for the
plaintiff in any such action, the indemnifying party agrees to indemnify and
hold harmless any indemnified party from and against any loss or liability by
reason of such settlement or judgment. No indemnifying party shall, without the
prior written consent of the indemnified party (which consent shall not be
unreasonably withheld), effect any settlement of any pending or threatened
proceeding in respect



                  NRG Northeast Registration Rights Agreement


<PAGE>   14


                                       -14-

of which any indemnified party is or could have been a party and indemnity
could have been sought hereunder by such indemnified party, unless such
settlement includes an unconditional release of such indemnified party from all
liability on claims that are the subject matter of such proceeding.

                  7.       Contribution. If the indemnification provided for in
Section 6 is unavailable or insufficient to hold harmless an indemnified party
under Section 6(a) or 6(b), then each indemnifying party shall, in lieu of
indemnifying such indemnified party, contribute to the amount paid or payable
by such indemnified party as a result of such loss, claim, damage or liability,
or action in respect thereof, (i) in such proportion as shall be appropriate to
reflect the relative benefits received by the Registrants from the offering and
sale of the Securities, on the one hand, and a Holder, Initial Purchaser or
Exchange Dealer with respect to the sale by such Holder, Initial Purchaser or
Exchange Dealer of Securities, Exchange Securities or Private Exchange
Securities, on the other, or (ii) if the allocation provided by clause (i)
above is not permitted by applicable law, in such proportion as is appropriate
to reflect not only the relative benefits referred to in clause (i) above but
also the relative fault of the Registrants on the one hand and such Holder,
Initial Purchaser or Exchange Dealer on the other with respect to the
statements or omissions that resulted in such loss, claim, damage or liability,
or action in respect thereof, as well as any other relevant equitable
considerations. The relative benefits received by the Registrants on the one
hand and a Holder on the other with respect to such offering and such sale
shall be deemed to be in the same proportion as the total net proceeds from the
offering of the Securities (before deducting expenses) received by or on behalf
of the Registrants, on the one hand, bear to the total proceeds received by
such Holder, Initial Purchaser or Exchange Dealer with respect to its sale of
Securities, Exchange Securities or Private Exchange Securities on the other.
The relative fault shall be determined by reference to, among other things,
whether the untrue or alleged untrue statement of a material fact or the
omission or alleged omission to state a material fact relates to the
Registrants or information supplied by the Registrants on the one hand or to
any Holders' Information supplied by such Holder or information furnished by
such Initial Purchaser or Exchange Dealer, on the other, the intent of the
parties and their relative knowledge, access to information and opportunity to
correct or prevent such untrue statement or omission. The parties hereto agree
that it would not be just and equitable if contributions pursuant to this
Section 7 were to be determined by pro rata allocation or by any other method
of allocation that does not take into account the equitable considerations
referred to herein. The amount paid or payable by an indemnified party as a
result of the loss, claim, damage or liability, or action in respect thereof,
referred to above in this Section 7 shall be deemed to include, for purposes of
this Section 7, subject to the limitations set forth above, any legal or other
expenses reasonably incurred by such indemnified party in connection with
investigating or defending or preparing to defend or appearing as a third party
witness in connection with any such action or claim. Notwithstanding the
provisions of this Section 7, an indemnifying party that is a Holder of
Securities, Exchange Securities or Private Exchange Securities shall not be
required to contribute any amount in excess of the amount by which the total
price at which the Securities, Exchange Securities or Private Exchange
Securities sold by such indemnifying party to any purchaser exceeds the amount
of any damages which such indemnifying party has otherwise paid or become
liable to pay by reason of any untrue or alleged untrue statement or omission
or alleged omission. No person guilty of fraudulent misrepresentation (within
the meaning of Section 11(f) of the Securities Act) shall be entitled to
contribution from any person who was not guilty of such fraudulent
misrepresentation.



                  NRG Northeast Registration Rights Agreement


<PAGE>   15


                                       -15-

                  8. Rules 144 and 144A. The Registrants shall use their
reasonable best efforts to file the reports required to be filed by it under
the Securities Act and the Exchange Act in a timely manner and, if at any time
the Registrants are not required to file such reports, they will, upon the
written request of any Holder of Transfer Restricted Securities, make available
to such Holder information that is necessary to permit sales of such Holder's
securities pursuant to Rules 144 and 144A. The Registrants covenant that they
will use their reasonable best efforts to take such further action as any
Holder of Transfer Restricted Securities may reasonably request, all to the
extent required from time to time to enable such Holder to sell Transfer
Restricted Securities without registration under the Securities Act within the
limitation of the exemptions provided by Rules 144 and 144A (including, without
limitation, the requirements of Rule 144A(d)(4)). Upon the written request of
any Holder of Transfer Restricted Securities, the Registrants shall deliver to
such Holder a written statement as to whether it has complied with such
requirements. Notwithstanding the foregoing, nothing in this Section 8 shall be
deemed to require the Registrants to register any of their securities pursuant
to the Exchange Act.

                  9. Underwritten Registrations. If any of the Transfer
Restricted Securities covered by any Shelf Registration Statement are to be
sold in an underwritten offering, the investment banker or investment bankers
and manager or managers that will administer the offering will be selected by
the Holders of a majority in aggregate principal amount of such Transfer
Restricted Securities included in such offering, subject to the consent of the
Registrants, and such Holders shall be responsible for all underwriting
commissions and discounts in connection therewith.

                  No person may participate in any underwritten registration
hereunder unless such person (i) agrees to sell such person's Transfer
Restricted Securities on the basis reasonably provided in any underwriting
arrangements approved by the persons entitled hereunder to approve such
arrangements and (ii) completes and executes all questionnaires, powers of
attorney, indemnities, underwriting agreements and other documents reasonably
required under the terms of such underwriting arrangements.

                  10. Miscellaneous. (a) Amendments and Waivers. The provisions
of this Agreement may not be amended, modified or supplemented, and waivers or
consents to departures from the provisions hereof may not be given, unless the
Registrants have obtained the written consent of Holders of a majority in
aggregate principal amount of the Securities, the Exchange Securities and the
Private Exchange Securities, taken as a single class. Notwithstanding the
foregoing, a waiver or consent to depart from the provisions hereof with
respect to a matter that relates exclusively to the rights of Holders whose
Securities, Exchange Securities or Private Exchange Securities are being sold
pursuant to a Registration Statement or to Holders of Transfer Restricted
Securities and that does not directly or indirectly affect the rights of other
Holders may be given by Holders of a majority in aggregate principal amount of
the Securities, the Exchange Securities and the Private Exchange Securities
being sold by such Holders pursuant to such Registration Statement or Holders
of Transfer Restricted Securities, as the case may be.

                  (b)       Notices. All notices and other communications
provided for or permitted hereunder shall be made in writing by hand-delivery,
first-class mail, telecopier or air courier guaranteeing next-day delivery:



                  NRG Northeast Registration Rights Agreement


<PAGE>   16


                                       -16-

                  (1)       if to a Holder, at the most current address given
         by such Holder to the Registrants in accordance with the provisions of
         this Section 10(b), which address initially is, with respect to each
         Holder, the address of such Holder maintained by the Registrar under
         the Indenture, with a copy in like manner to Chase Securities Inc. and
         Salomon Smith Barney Inc.;

                  (2)       if to an Initial Purchaser, initially at its
         address set forth in the Purchase Agreement; and

                  (3)       if to the Registrants, initially at the addresses
         of each Registrant set forth in the Purchase Agreement.

                  All such notices and communications shall be deemed to have
been duly given: when delivered by hand, if personally delivered; one business
day after being delivered to a next-day air courier; five business days after
being deposited in the mail; and when receipt is acknowledged by the
recipient's telecopier machine, if sent by telecopier.

                  (c)       Successors And Assigns.  This Agreement shall be
binding upon the Registrants and its successors and assigns.

                  (d)       Counterparts. This Agreement may be executed in any
number of counterparts (which may be delivered in original form or by
telecopier) and by the parties hereto in separate counterparts, each of which
when so executed shall be deemed to be an original and all of which taken
together shall constitute one and the same agreement.

                  (e)       Definition of Terms. For purposes of this
Agreement, (a) the term "business day" means any day on which the New York
Stock Exchange, Inc. is open for trading, (b) the term "subsidiary" has the
meaning set forth in Rule 405 under the Securities Act and (c) except where
otherwise expressly provided, the term "affiliate" has the meaning set forth in
Rule 405 under the Securities Act.

                  (f)       Headings.  The headings in this Agreement are for
convenience of reference only and shall not limit or otherwise affect the
meaning hereof.

                  (g)       Governing Law. This Agreement shall be governed by
and construed in accordance with the laws of the State of New York, without
reference to the conflict of law rules thereof.

                  (h)       Remedies. In the event of a breach by any of the
Registrants or by any Holder of any of their obligations under this Agreement,
each Holder or each of the Registrants, as the case may be, in addition to
being entitled to exercise all rights granted by law, including recovery of
damages (other than the recovery of damages for a breach by the Registrants of
its obligations under Sections 1 or 2 hereof for which liquidated damages have
been paid pursuant to Section 3 hereof), will be entitled to specific
performance of its rights under this Agreement. Each Registrant and each Holder
agrees that monetary damages would not be adequate



                  NRG Northeast Registration Rights Agreement


<PAGE>   17


                                       -17-

compensation for any loss incurred by reason of a breach by it of any of the
provisions of this Agreement and hereby further agree that, in the event of any
action for specific performance in respect of such breach, it shall waive the
defense that a remedy at law would be adequate.

                  (i)       No Inconsistent Agreements. Each Registrant
represents, warrants and agrees that (i) it has not entered into, shall not, on
or after the date of this Agreement, enter into any agreement that conflicts
with the provisions hereof, (ii) it has not previously entered into any
agreement which remains in effect granting any registration rights with respect
to any of its debt securities to any person and (iii) without limiting the
generality of the foregoing, without the written consent of the Holders of a
majority in aggregate principal amount of the then outstanding Transfer
Restricted Securities, it shall not grant to any person the right to request
the Registrants to register any debt securities of the Company under the
Securities Act unless the rights so granted are not in conflict or inconsistent
with the provisions of this Agreement.

                  (j)       Severability. The remedies provided herein are
cumulative and not exclusive of any remedies provided by law. If any term,
provision, covenant or restriction of this Agreement is held by a court of
competent jurisdiction to be invalid, illegal, void or unenforceable, the
remainder of the terms, provisions, covenants and restrictions set forth herein
shall remain in full force and effect and shall in no way be affected, impaired
or invalidated, and the parties hereto shall use their reasonable best efforts
to find and employ an alternative means to achieve the same or substantially
the same result as that contemplated by such term, provision, covenant or
restriction. It is hereby stipulated and declared to be the intention of the
parties that they would have executed the remaining terms, provisions,
covenants and restrictions without including any of such that may be hereafter
declared invalid, illegal, void or unenforceable.





                  NRG Northeast Registration Rights Agreement


<PAGE>   18
                                      -18-

                  Please confirm that the foregoing correctly sets forth the
agreement among the Registrants and the Initial Purchasers.

                                Very truly yours,


                                NRG NORTHEAST GENERATING LLC


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


                                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



                  NRG Northeast Registration Rights Agreement


<PAGE>   19


                                       -19-

                                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




                  NRG Northeast Registration Rights Agreement


<PAGE>   20


                                       -20-




Accepted on behalf of each of the Initial Purchasers:

CHASE SECURITIES INC.


By /s/ Christopher Lowe
  ----------------------------
   Authorized Signatory


SALOMON SMITH BARNEY INC.


By /s/ Barry Gold
  ----------------------------
   Authorized Signatory




                  NRG Northeast Registration Rights Agreement