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                                                                     Exhibit 4.2

                  FIRST SUPPLEMENTAL INDENTURE dated as of November 20, 2000
between Cedar Brakes I, L.L.C. (the "Issuer") and Bankers Trust Company, as
trustee (the "Trustee" and, together with the Issuer, the "Parties").


                                   WITNESSETH:


                  WHEREAS, the Issuer and the Trustee have entered into an
Indenture dated as of September 26, 2000 (the "Indenture"), which provides for
the creation and issuance of 8.50% senior secured bonds due 2014 in the
aggregate principal amount of $310,600,000;

                  WHEREAS, the Parties desire to amend certain provisions of the
Indenture pursuant to Section 1001 thereof in order to clarify certain defined
terms related to the Exchange Offer and the Exchange Offer process and make
other related technical amendments as provided herein;

                  NOW, THEREFORE, in consideration of the premises contained
herein and for other good and valuable consideration receipt of which is hereby
acknowledged, the Parties hereby agree as follows:



                                    ARTICLE I

                                   DEFINITIONS

Unless otherwise defined herein, and subject to the amendments herein, terms
defined in the Indenture shall have such defined meanings when used herein.



                                   ARTICLE II

                             AMENDMENTS TO INDENTURE

                  SECTION 201. Amendment of Recitals. The first Whereas clause
of the Indenture is hereby deleted in its entirety and replaced with the
following paragraph:

                  "WHEREAS, the Issuer has duly authorized the creation of an
issue of 8.50% Senior Secured Bonds due 2014 in the aggregate principal amount
of $310,600,000, and 8.50% Series B Senior Secured Bonds due 2014 to be issued
in



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exchange for the 8.50% Senior Secured Bonds due 2014, pursuant to the
Registration Rights Agreement (as defined herein) and, to provide therefor, the
Issuer has duly authorized the execution and delivery of this Indenture."

                  SECTION 202. Amendment of Exhibit A to the Indenture. Exhibit
A to the Indenture is hereby amended by:

                  (a) deleting the definition of "Bonds" and replacing it with
                      the following definition:

                  ""Bonds" means, collectively, the Initial Bonds, the Private
Exchange Bonds, if any, and the Unrestricted Bonds, treated as a single class of
securities, as amended or supplemented from time to time in accordance with the
terms of this Indenture, that are issued pursuant to this Indenture;
individually, a "Bond"."

                  (b) deleting the definition of "Exchange Offer" and replacing
                      it with the following definition:

                  ""Exchange Offer" means the offer that may be made by the
Issuer pursuant to the Registration Rights Agreement to the Holders of the
Initial Bonds to exchange their Initial Bonds for the Exchange Bonds."

                  (c) inserting the following definitions in the appropriate
                      alphabetical order therein:

                  ""Exchange Bonds" means the 8.50% Series B Senior Secured
Bonds due 2014, to be issued in exchange for the Initial Bonds pursuant to the
Registration Rights Agreement."

                  ""Initial Bonds" means, collectively, the 8.50% Senior Bonds
due 2014 of the Issuer issued on the Closing Date for so long as such securities
constitute Restricted Securities."

                  ""Private Exchange Bonds" has the meaning provided in the
Registration Rights Agreement."

                  ""Restricted Security" has the meaning assigned to such term
in Rule 144(a)(3) under the Securities Act; provided, however, that the Trustee
shall be entitled to request and conclusively rely on an Opinion of Counsel with
respect to whether any Bond constitutes a Restricted Security."


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                  ""Unrestricted Bonds" means one or more Bonds that do not and
are not required to bear the restrictive legends set forth in Section 202,
including, without limitation, the Exchange Bonds."

                  SECTION 203. Amendment to Section 303 of the Indenture.
Section 303 of the Indenture is hereby amended by deleting the third paragraph
thereof and replacing it with the following paragraph:

                  "At any time and from time to time after the execution and
delivery of this Indenture, the Issuer may deliver Bonds executed by the Issuer
to the Trustee for authentication, together with the Issuer Order for the
authentication and delivery of such Bonds, directing the Trustee to authenticate
the Bonds and certifying that all conditions precedent to the issuance of Bonds
contained herein have been fully complied with. Each such Issuer Order shall
specify the amount of Bonds to be authenticated, the date on which the Bonds are
to be authenticated, whether the bonds are to be Initial Bonds, Private Exchange
Bonds or Unrestricted Bonds and whether the Bonds are to be issued as Physical
Bonds or Global Bonds or such other information as the Trustee may reasonably
request. The Trustee shall receive an Officers' Certificate and an Opinion of
Counsel of the Issuer in connection with such authentication of Bonds. Upon
receipt of any such Issuer Order, the Trustee shall, in accordance with such
Issuer Order, authenticate (i) Initial Bonds for original issue in the aggregate
principal amount not to exceed $310,600,000, (ii) Private Exchange Bonds from
time to time for issue only in exchange for a like principal amount of Initial
Bonds and (iii) Unrestricted Bonds from time to time only (A) in exchange for a
like principal amount of Initial Bonds or (B) in an aggregate principal amount
of not more than the excess of $310,600,000 over the sum of the aggregate
principal amount of (x) Initial Bonds then outstanding, (y) Private Exchange
Bonds then outstanding and (z) Unrestricted Bonds issued in accordance with
(iii)(A) above. The aggregate principal amount of Bonds outstanding at any time
may not exceed $310,600,000."




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                                   ARTICLE III

                                  MISCELLANEOUS

                  SECTION 301. Limited Effect. Except as expressly amended
hereby, all of the provisions of the Indenture shall continue to be, and shall
remain, in full force and effect in accordance with their terms.

                  SECTION 302. Construction As One Instrument. This First
Supplemental Indenture shall be construed as supplementing and forming part of
the Indenture, and shall be read accordingly.

                  SECTION 303. Severability. If at any time any one or more of
the provisions hereof is or becomes illegal, invalid or unenforceable in any
respect under the applicable law of any jurisdiction, neither the validity or
enforceability of the remaining provisions hereof nor the legality, validity or
enforceability of such provisions under the applicable law of any other
jurisdiction shall in any way be affected or impaired thereby.

                  SECTION 304. Counterparts. This First Supplemental Indenture
may be executed in counterparts and by each of the Parties on separate
counterparts, both of which shall constitute one and the same instrument

                  SECTION 305 Binding Effect. This First Supplemental Indenture
shall become effective when it shall have been executed by the Parties.

                  SECTION 306. Governing Law. This FIRST SUPPLEMENTAL INDENTURE
shall be governed by, and construed in accordance with, the laws of the State of
NEW YORK (without giving effect to the principles thereof relating to conflicts
of law except section 5-1401 of the new york GENERAL OBLIGATIONS LAW).


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                  IN WITNESS WHEREOF, the Parties have caused this First
Supplemental Indenture to be duly executed as of the date and year first above
written.

                                        CEDAR BRAKES I, L.L.C.



                                        By:  /s/ JOHN L. HARRISON
                                             -----------------------------------
                                             Name: John L. Harrison
                                             Title Vice President, Senior
                                                   Managing Director and Class
                                                   A Manager



                                        BANKERS TRUST COMPANY
                                             Trustee, Paying Agent and Registrar



                                        By:  /s/ MARION ZINOWSKI
                                             -----------------------------------
                                             Name: Marion Zinowski
                                             Title Assistant Vice President



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