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                                                                     Exhibit 4.2

                            SIERRA PACIFIC RESOURCES

                           7.93% SENIOR NOTE DUE 2007

NO.: R-1                                                 CUSIP NO.:  826428 AD 6

$300,000,000

       SIERRA PACIFIC RESOURCES, a corporation duly organized and existing under
the laws of the State of Nevada (herein called the "Company", which term
includes any successor Person under the Indenture hereinafter referred to), for
value received, hereby promises to pay to The Bank of New York, as Purchase
Contract Agent under the Purchase Contract Agreement, dated as of November 16,
2001 between Sierra Pacific Resources and The Bank of New York, as Purchase
Contract Agent, or its registered assigns (the "Holder"), the principal sum of
THREE HUNDRED MILLION DOLLARS ($300,000,000), or such other principal amount as
shall be set forth in the Schedule of Increases or Decreases attached hereto, on
November 15, 2007 in such coin or currency of the United States of America as at
the time of payment is legal tender for payment of public or private debts and
to pay interest thereon from November 16, 2001 or from the most recent Interest
Payment Date to which interest has been paid or duly provided for, quarterly in
arrears on February 15, May 15, August 15 and November 15 of each year,
commencing on February 15, 2001, at the rate of 7.93% per annum to, but
excluding, either (1) the Remarketing Settlement Date, if there has been a
Successful Remarketing, or (2) the Purchase Contract Settlement Date, if a
Failed Remarketing has occurred or, if there is not a Remarketing at all
pursuant to clause (c) of the definition of "Reset Rate" in the Officers'
Certificate, and at the Reset Rate thereafter, until the principal hereof is
paid or made available for payment.

       Payments of interest on the Senior Notes will include interest accrued
to, but excluding, the respective Interests Payment Dates. Interest payments for
the Senior Notes shall be computed and paid (1) for any full quarterly period,
on the basis of a 360-day year of twelve 30-day months, (2) for any period
shorter than a full quarterly period, on the basis of a 30-day month and (3) for
any period less than a month, on the basis of the actual number of days elapsed
per 30-day month. In the event that any date on which interest is payable on the
Senior Notes is not a Business Day, then payment of the interest payable on such
date will be made on the next succeeding day that is a Business Day (and without
any interest or payment in respect of any such delay), in each case with the
same force and effect as if made on the date the payment was originally due and
payable; PROVIDED, HOWEVER, if such Business Day is in the next calendar year,
then such payment will be made on the preceding Business Day.

       Any principal of or installment of interest on the Senior Notes that is
overdue shall bear interest at the interest rate then borne by the Senior Notes
(to the extent that the payment of such interest shall be legally enforceable),
from the dates such amounts are due until they are paid or made available for
payment, and such interest shall be payable on demand by the Holders.

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       Interest shall be paid quarterly in arrears on each Interest Payment Date
to the Person in whose name the Senior Notes are registered on the Regular
Record Date for such Interest Payment Date; PROVIDED that, interest payable at
the Stated Maturity of principal as provided herein will be paid to the Person
to whom principal is payable. Any such interest that is not so punctually paid
or duly provided for will forthwith cease to be payable to the Holders on such
Regular Record Date and may either be paid to the Person or Persons in whose
name the Senior Notes are registered at the close of business on a special
record date (as such term is used in Section 2.12 of the Indenture) for the
payment of such defaulted interest to be fixed by the Company, notice whereof
shall be given to Holders of the Senior Notes not less than ten days prior to
such special record date, or be paid at any time in any other lawful manner not
inconsistent with the requirements of any securities exchange, if any, on which
the Senior Notes may be listed, and upon such notice as may be required by any
such exchange, all as set forth in Section 2.12 of the Indenture.

       The principal amount of this Senior Note may be increased or decreased as
specified in the Officers' Certificate pursuant to which this Senior Note is
issued.

       Reference is hereby made to the further provisions of this Senior Note
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 referred to on the reverse hereof by manual signature, this Senior Note
shall not be entitled to any benefit under the Indenture or be valid or
obligatory for any purpose.

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       IN WITNESS WHEREOF, the Company has caused this instrument to be duly
executed.



Dated:                                   SIERRA PACIFIC RESOURCES



                                         By:
                                            ------------------------------------
                                            Name:
                                            Title:




                          CERTIFICATE OF AUTHENTICATION



     This is one of the Securities of the series designated herein referred to
in the within-mentioned Indenture.

                                         THE BANK OF NEW YORK, as Trustee



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

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                            [REVERSE OF SENIOR NOTE]

       1. INDENTURE; NOTES.

          This Senior Note is one of a duly authorized series of Securities of
the Company (the "Senior Notes"), issued and to be issued in one or more series
under an Indenture, dated as of May 1, 2000 (the "Indenture"), between the
Company and The Bank of New York, as Trustee (the "Trustee", which term includes
any successor trustee under the Indenture), and reference is hereby made to the
Indenture for a statement of the respective rights, limitations of rights,
duties and immunities thereunder of the Company, the Trustee and the Holders of
the Securities and of the terms upon which the Securities are, and are to be,
authenticated and delivered. The terms, conditions and provisions of the
Securities are those stated in the Indenture, those made part of the Indenture
by reference to the Trust Indenture Act of 1939, as amended, and those set forth
in this Senior Note. To the extent that the terms, conditions and other
provisions of this Senior Note modify, supplement or are consistent with those
of the Indenture, the terms, conditions and other provisions of the Indenture
shall govern.

       The maximum aggregate principal amount of Senior Notes that may be
authenticated and delivered under the Indenture (except for Senior Notes
authenticated and delivered upon registration or transfer of or in exchange for,
or in lieu of other Senior Notes pursuant to Section 2.06, 2.07, 2.09 or 3.07 of
the Indenture) shall be $300,000,000 (or up to $345,000,000 if the Underwriters
exercise their over-allotment option as set forth in the Underwriting
Agreement). The Senior Notes are issuable only in denominations of $50 and any
integral multiple thereof.

       All capitalized terms that are used but not defined in this Senior Note
shall have the meanings assigned to them in the Officers' Certificate.

       2. RANKING.

       The Senior Notes shall constitute the senior, unsecured and
unsubordinated debt obligations of the Company and shall rank equally in right
of payment with all other existing and future senior, unsecured and
unsubordinated debt obligations of the Company.

       3. FORM; TRANSFER, REGISTRATION AND EXCHANGE.

       Initially, the Senior Notes (including the Senior Notes, if any, issued
pursuant to the exercise of the Underwriters' over-allotment option as set forth
in the Underwriting Agreement) that are components of certain securities of the
Company referred to as Corporate PIES (the "Corporate PIES") will be issued in
definitive form (the "Certificated Notes") registered in the name of The Bank of
New York, as Purchase Contract Agent (the "Purchase Contract Agent"), under the
Purchase Contract Agreement dated as of November 16, 2001 between the Company
and the Purchase Contract Agent (the "Purchase Contract Agreement"). Senior
Notes that are not components of Corporate PIES shall initially be issued in the
form of one or more global Senior Notes (each a "Global Senior Note") in the
name of Cede & Co. (as nominee for The Depository Trust Company (the
"Depository"), the initial securities depository for the Global Senior Notes.
The Certificated Notes and the Global Senior Notes may bear such legends as
either the Purchase Contract Agent or DTC, respectively, may reasonably request.

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       So long as any Senior Notes constitute components of Corporate PIES, they
shall be issued in the form of Certificated Notes. Senior Notes that no longer
constitute components of Corporate PIES shall be issued in the form of Global
Senior Notes. Each Global Senior Note or Certificated Note, as applicable, shall
represent such of the outstanding Senior Notes as shall be specified therein and
each shall provide that it shall represent the aggregate principal amount of
outstanding Senior Notes from time to time endorsed thereon and that the
aggregate principal amount of outstanding Senior Notes represented thereby may
from time to time be reduced or increased, as appropriate, to reflect exchanges
and redemptions. Any endorsement of a Global Senior Note to reflect the amount
of any increase or decrease in the aggregate principal amount of outstanding
Senior Notes represented thereby shall be made by the Trustee, as custodian of
the Global Senior Notes (the "Custodian"), in accordance with instructions as
further set forth below. Any endorsement of a Certificated Note to reflect the
amount of any decrease in the aggregate principal amount of outstanding
Certificated Notes represented thereby shall be made by the Collateral Agent
pursuant to and in accordance with further instructions as set forth below.

       No beneficial owner of the Senior Notes shall receive a Certificated Note
representing such beneficial owner's interest in such Global Senior Notes,
except as provided in Section 2.06 of the Indenture. Unless and until
Certificated Notes have been issued to the beneficial owners of the Senior Notes
pursuant to Section 2.06 of the Indenture, the rights of the beneficial owners
of the Senior Notes shall be exercised only through the Depositary and shall be
limited to those established by law and agreements between such beneficial
owners and the Depositary and/or the Depositary Participants. The Depositary
shall make book-entry transfers among its participants and receive and transmit
any payments on the Global Senior Notes to such participants; PROVIDED that,
solely for the purposes of determining whether the Holders of the requisite
amount of the Senior Notes have voted on any matter provided for in the
Indenture, the Company may rely conclusively on, and shall be protected in
relying on, any written instrument (including a proxy) delivered to the Company
by the Depositary setting forth the votes of the beneficial owners of the Senior
Notes or assigning the right to vote on any matter to any other Persons either
in whole or in part. The Senior Notes are subject to transfer, registration and
exchange as set forth in Section 2.06 of the Indenture, as supplemented by the
Officers' Certificate.

       The Company shall execute, and the Trustee shall authenticate and
deliver, in each case, pursuant to Section 2.02 of the Indenture, one or more
Global Senior Notes that (i) shall represent and be denominated in an amount
equal to the aggregate principal amount of all of the Senior Notes to be issued
in the form of Global Senior Notes and not yet canceled, (ii) shall be
registered in the name of the Depositary for the Senior Notes or the nominee of
such Depositary and (iii) shall be delivered by the Trustee to such Depositary
or pursuant to such Depositary's instructions.

       Reference is hereby made to Section 2.06 of the Indenture for the
provisions relating to the transfer, registration and exchange of the Senior
Notes. Notwithstanding any other provisions of the Indenture (other than the
provisions set forth in Section 2.06 of the Indenture), Global Senior Notes may
not be transferred as a whole except by the Depositary to a nominee of the
Depositary or by a nominee of the Depositary to the Depositary or another
nominee of the Depositary or by the Depositary or any such nominee to a
successor Depositary or a nominee of such successor Depositary. Interests of
beneficial owners may be transferred or exchanged for

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Senior Notes not represented by a Global Senior Note, and Senior Notes not
represented by a Global Senior Note may be transferred or exchanged for a Global
Senior Notes or Senior Notes, in accordance with rules of the Depositary and the
provisions of Section 2.06 of the Indenture.

       If any beneficial interest in a Global Senior Note is exchanged for or
transferred to a person who will take delivery thereof in the form of a
beneficial interest in another Global Senior Note or for Certificated Notes, the
principal amount of Senior Notes represented by such Global Senior Note shall be
reduced accordingly and an endorsement shall be made on such Global Senior Note
by the Collateral Agent or by the Depositary at the direction of the Trustee to
reflect such reduction; and if the beneficial interest is being exchanged for or
transferred to a person who will take delivery thereof in the form of a
beneficial interest in another Global Senior Note, such other Global Senior Note
shall be increased accordingly and an endorsement shall be made on such Global
Senior Note by the Trustee or by the Depositary at the direction of the Trustee
to reflect such increase.

       In the event that any Pledged Senior Notes are to be released from the
Pledge of the Pledge Agreement and delivered to the Purchase Contract Agent
pursuant to Section 5.2(b) of the Pledge Agreement (a "Released Note"), as a
result of the creation of one or more Treasury PIES as provided in Section 5.2
of the Pledge Agreement, such release and delivery shall be evidenced by an
endorsement by the Collateral Agent on the Certificated Note held by the
Collateral Agent reflecting a reduction in the principal amount of such
Certificated Note equal in amount (the "Reduced Principal Amount") to the
principal amount of the Released Note. The Collateral Agent shall confirm any
such Reduced Principal Amount by telecopying or otherwise delivering a photocopy
of such endorsement made on the Certificated Note evidencing such Reduced
Principal Amount to the Trustee at the telecopier number or address of the
Purchase Contract Agent provided for notices to the Purchase Contract Agent in
the Pledge Agreement (or at such other telecopier or address as the Trustee
shall provide to the Collateral Agent). Upon receipt of such confirmation, the
Trustee shall instruct the Custodian to increase the principal amount of a
Global Note held by the Custodian in an amount equal to the Reduced Principal
Amount by an endorsement made by the Custodian on such Global Note to reflect
such increase.

       In the event that a Senior Note is transferred to the Collateral Agent
pursuant to Section 5.3(a) of the Pledge Agreement (a "Subjected Note") in
connection with the recreation of Corporate PIES as provided in Section 5.3 of
the Pledge Agreement, such transfer shall be evidenced by an endorsement by the
Collateral Agent on the Certificated Note held by the Collateral Agent
reflecting an increase in the principal amount of such Certificated Note equal
in amount (the "Increased Principal Amount") to the principal amount of such
Subjected Note. The Collateral Agent shall confirm any such Increased Principal
Amount by telecopying or otherwise delivering a photocopy of such endorsement
made on the Certificated Note evidencing such Increased Principal Amount to the
Trustee at the telecopier number or address of the Purchase Contract Agent
provided for notices to the Purchase Contract Agent in the Pledge Agreement (or
at such other telecopier or address as the Trustee shall provide to the
Collateral Agent). Upon receipt of such confirmation, the Trustee shall instruct
the Custodian to decrease the principal amount of the Senior Global Note held by
the Custodian in an amount equal to the Increased Principal Amount by an
endorsement made by the Custodian on such Senior Global Note to reflect such
decrease.

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       4. PLEDGE.

       Upon initial issuance, the Senior Notes shall be pledged to the
Collateral Agent for the benefit of the Company, pursuant to the terms of the
Pledge Agreement, as collateral to secure the obligations of the Holders of
Corporate PIES to purchase the Common Stock in accordance with the terms of the
Purchase Contract Agreement. The Senior Notes may be transferred, in whole or in
part, only in accordance with the terms and conditions set forth in the
Indenture, the Pledge Agreement and the Purchase Contract Agreement. To the
fullest extent permitted by law, any transfer or purported transfer of any
Senior Note not made in accordance with the Indenture shall be null and void.
Subject to this Section, the Senior Notes shall be freely transferable.

       5. PLACE AND METHOD OF PAYMENT.

       Payments of the principal of and interest on the Senior Notes shall be
made at the office of the Paying Agent, with any such payment that is due at the
Stated Maturity of any Senior Notes being made upon surrender of such Senior
Notes to the Paying Agent. Payments of interest (including interest on any
Interest Payment Date) will be made at the option of the Company, (i) by check
mailed to the address of the Person entitled thereto as such address shall
appear in the Security Register or (ii) by wire transfer at such place and to
such account at a banking institution in the United States as may be designated
in writing to the Trustee at least sixteen days prior to the date for payment by
the Person entitled thereto.

       6. NO REDEMPTION OR SINKING FUND.

       The Senior Notes shall not be redeemable at the option of the Company,
the Holders or otherwise; and there shall be no sinking fund with respect to the
Senior Notes.

       7. REMARKETING.

            (i) REMARKETING RIGHTS. (A) The Remarketing Senior Notes shall be
remarketed in the Remarketing pursuant to the Remarketing Procedures. All
holders of PIES Senior Notes, including those who have attempted to effect a
Cash Settlement pursuant to Section 5.8 of the Purchase Contract Agreement,
Early Settlement pursuant to Section 5.9 of the Purchase Contract Agreement or
Merger Settlement pursuant to Section 5.10 of the Purchase Contract Agreement
but have failed to follow the procedures for such settlements shall be deemed to
have consented to the Remarketing of their Senior Notes pursuant to the
Remarketing Procedures in any Remarketing, or in the case of an unsuccessful
Cash Settlement, in the Final Remarketing. The right of each Holder of Senior
Notes to have its Senior Notes remarketed will be limited, however, to the
extent that (i) the Remarketing Agent conducts a Remarketing pursuant to the
terms of the Remarketing Agreement, (ii) the Remarketing Agent is able to find a
purchaser or purchasers for the tendered Senior Notes, (iii) such purchaser or
purchasers deliver the purchase price therefor to the Remarketing Agent and (iv)
the Remarketing may not commenced or be consummated pursuant to applicable law.
In addition, all holders of Senior Notes shall be deemed to have consented to
the Remarketing Procedures and the terms of the Purchase Contract Agreement, the
Pledge Agreement and the Remarketing Agreement with respect to the pledge and
transfer and other provisions of these agreements with respect to their Senior
Notes, pursuant to the terms of such agreements.

<Page>


       (B) Holders of Senior Notes comprising part of Corporate PIES may elect
not to participate in the Remarketing by creating Treasury PIES if it notifies
the Purchase Contract Agent of such election and delivers the specific U.S.
Treasury Security or U.S. Treasury Securities not later than 5:00 p.m. (New York
City time) on the Election Date. A Holder that has not so created Treasury PIES
by delivering the Treasury Security or Treasury Securities pursuant to this
paragraph and Section 3.13 of the Purchase Contract Agreement shall be deemed to
have elected to participate in any Remarketing.

       (C) Holders of Separated Senior Notes may elect to have such Separated
Senior Notes remarketed, if such holder delivers (a) to the Trustee and the
Collateral Agent a notice of that election, by use of a notice in substantially
the form of Exhibit B to the Officers' Certificate, specifying the aggregate
principal amount of Senior Notes to be remarketed, and (b) such Separated Senior
Notes, by book-entry transfer or other appropriate procedures, to the Collateral
Agent for Remarketing, in each case, by 5:00 p.m. (New York City time) on the
Election Date. Once the holder of such Separated Senior Notes delivers such
notice and Separated Senior Notes as specified in the preceding sentence, such
election may not be withdrawn and may not be conditioned upon the level at which
the Reset Rate is established in the Remarketing; PROVIDED, HOWEVER, that if
such a holder delivers only such a notice but not the Separated Senior Notes
subject to the notice, or vice versa, then none of such holder's Separated
Senior Notes shall be included in the Remarketing. On the Business Day
immediately preceding the Initial Remarketing Date, the Collateral Agent shall
notify the Remarketing Agent of the aggregate number of Separated Senior Notes
to be remarketed. If there is a Successful Remarketing, the Collateral Agent
shall transfer such Separated Senior Notes in accordance with the instructions
provided by the Remarketing Agent pursuant to the Remarketing Agreement. If a
Failed Remarketing occurs, the Collateral Agent shall Transfer such Separated
Senior Notes to the holders by the end of the Business Day following the Failed
Remarketing.

       (ii) REMARKETING AND RATE RESET PROCEDURES. (A) On the seventh Business
Day prior to the Initial Remarketing Date or the Final Remarketing Date, as
applicable, the Company shall give notice of the Remarketing in an Authorized
Newspaper, including the specific U.S. Treasury Security or Treasury Securities
(including the CUSIP number and/or the principal terms of such Treasury Security
or Treasury Securities) that must be delivered by Holders of Corporate PIES that
elect not to participate in the Remarketing pursuant to Section 5.3(e) of the
Purchase Contract Agreement, no later than 5:00 p.m. (New York City time) on the
Election Date. Promptly after 11:00 a.m. (New York City time) on the Business
Day preceding the Initial Remarketing Date, or the Final Remarketing Date, as
applicable, the Purchase Contract Agent shall notify the Remarketing Agent, the
Company, the Collateral Agent and the Trustee of the aggregate principal amount
of Pledged Senior Notes to be remarketed and the Collateral Agent, having
separately notified the Remarketing Agent, the Trustee and the Company of the
aggregate principal amount of Separated Senior Notes to be included in the
Remarketing by 11:00 a.m. (New York City time), on the Business Day immediately
preceding the Initial Remarketing Date or the Final Remarketing Date, as
applicable, shall concurrently therewith, pursuant to the Pledge Agreement,
deliver for Remarketing to the Remarketing Agent all Remarketing Senior Notes.

       (B) The Remarketing Agent shall use its commercially reasonable efforts
to remarket the Remarketing Senior Notes pursuant to the Remarketing Agreement.
If there is a Successful Remarketing, by approximately 4:30 p.m. (New York City
time) on the Remarketing Date,

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the Remarketing Agent shall advise, by telephone, the Trustee and the other
parties specified in the Purchase Contract Agreement, of the Reset Rate
determined in the Remarketing and the number of Remarketing Senior Notes
remarketed in the Remarketing.

       Upon receipt of the proceeds from a Successful Remarketing, the
Remarketing Agent shall among other actions specified by the Remarketing
Agreement:

       (I)     deduct and retain an amount equal to .25% of the proceeds of the
               principal amount of the Remarketing Senior Notes for the
               performance of its services as Remarketing Agent;

       (II)    if the Successful Remarketing occurs prior to the third Business
               Day preceding the Purchase Contract Settlement Date, use the
               remaining proceeds with respect to the Pledged Senior Notes from
               such Successful Remarketing to purchase the Treasury Portfolio,
               in open market transactions and/or at Treasury auctions, in the
               amount and types of Treasury securities describe in clauses
               (1)(i) and (2)(ii) of the definition of Remarketing Value related
               to the Pledged Senior Notes, and, on or prior to the third
               Business Day following the Remarketing Date (such date of
               settlement of the Remarketing, the "Remarketing Settlement Date")
               deliver such Treasury Portfolio to the Collateral Agent, or (II)
               if such Successful Remarketing occurs on the Final Remarketing
               Date, remit to the Collateral Agent the portion of the remaining
               proceeds with respect to the Pledged Senior Notes from such
               Successful Remarketing to be delivered to the Purchase Contract
               Agent in settlement of the Purchase Contracts;

       (III)   if any Separated Senior Notes were included in such successful
               Remarketing, remit to the Collateral Agent the remaining portion
               of the proceeds from the Successful Remarketing of such Separated
               Senior Notes in an amount described in clauses (1)(ii) and
               (2)(ii) of the definition of Remarketing Value for payment by the
               Collateral Agent to the holders of such Separated Senior Notes;
               and

       (IV)    remit any remaining balance of such proceeds after the
               application of such proceeds as set forth in clauses (I) through
               (III) above, if any, to the Purchase Contract Agent for the
               benefit of the Holders of the remarketed Pledged Senior Notes and
               to the Collateral Agent for the for the holders of any remarketed
               Separated Senior Notes on a pro rata basis;

PROVIDED, HOWEVER, that if such Successful Remarketing is consummated after 4:30
p.m. (New York City time) on such Remarketing Date and, despite using its
commercially reasonable efforts, the Remarketing Agent cannot cause the
applications of the proceeds specified above to

<Page>


occur on such Remarketing Date, then the Remarketing Agent may make such
applications and remittances on the next succeeding Business Day.

       Any distributions to Holders of funds described in paragraphs (I) through
(IV) above shall be payable at the office of the Purchase Contract Agent in The
City of New York maintained for that purpose or, at the option of the Holder or
the holder of Separated Senior Notes, as applicable, by check mailed to the
address of the Person entitled thereto at such address as it appears on the
Register or by wire transfer to an account specified by the Holder or the holder
of Separated Senior Notes, as applicable.

       (C) If a Failed Remarketing occurs:

            (i)    The Remarketing Agent shall notify by telephone by 4:00 p.m.
                   (New York City time) on the Final Remarketing Date the
                   Depositary, the Trustee, the Purchase Contract Agent, the
                   Collateral Agent and the Company that a Failed Remarketing
                   has occurred.

            (ii)   The Company shall cause a notice of the Failed Remarketing to
                   be sent to the Holders of all such Senior Notes and to be
                   published in an Authorized Newspaper, in each case, no later
                   than on the Business Day preceding the Purchase Contract
                   Settlement Date.

            (iii)  By the third Business Day following the Failed Remarketing,
                   the Remarketing Agent shall remit (A) to the Collateral Agent
                   the Remarketing Senior Notes that were formerly components of
                   the Corporate PIES and (B) to the Collateral Agent the
                   Separated Senior Notes, whereupon the Collateral Agent shall
                   transfer such Separated Senior Notes to the related Holders
                   thereof.

            (iv)   The Remarketing Agent shall determine the Reset Rate that
                   will be equal to the Two Year Benchmark Treasury in effect on
                   the Purchase Contract Settlement Date plus the Applicable
                   Spread.

            (v)    The Collateral Agent, under the Pledge Agreement and for the
                   benefit of the Company, may, on the written direction of the
                   Company, exercise its rights as a secured party with respect
                   to such Pledged Senior Notes, including those actions
                   specified below; PROVIDED that, if upon a Failed Remarketing,
                   the Collateral Agent exercises such rights for the benefit of
                   the Company with respect to such Pledged Senior Notes, any
                   accumulated and unpaid interest on such Senior Notes will
                   become payable by the Company to the Purchase Contract Agent
                   for payment to the Holders of the Corporate PIES to which
                   such Senior Notes relates. Such payment will be made by the
                   Company on or prior to 11:00 a.m. (New York City time), on
                   the Purchase Contract Settlement Date in lawful money of the
                   United States by certified or cashiers' check or wire
                   transfer in immediately available funds payable to or upon
                   the order of the Purchase Contract Agent.

<Page>


       With respect to any Pledged Senior Notes which are subject of a Failed
Remarketing, the Collateral Agent, for the benefit of the Company, reserves all
of its rights as a secured party with respect thereto and, subject to applicable
law, may, on the written directions of the Company, (i) retain such Senior Notes
in full satisfaction of the Holders' obligations under the related Purchase
Contracts or (ii) sell such Senior Notes in one or more public or private sales.

       (D) If all of the holders of Corporate PIES elect not to participate in
the Remarketing and no holders of Senior Notes that are not a component of
Corporate PIES elect to participate in the Remarketing and deliver their Senior
Notes and a notice of such election to the Collateral Agent, pursuant to and in
accordance with the Pledge Agreement then, (i) the Remarketing Agent shall, in
its sole discretion, determine the rate that, in its judgment, would have been
established had a Remarketing been held on the Remarketing Date, and such rate
shall be the Reset Rate; and (ii) by approximately 4:30 p.m. (New York City
time), on the third Business Day preceding the Purchase Contract Settlement
Date, the Remarketing Agent shall advise by telephone (promptly confirmed in
writing), the Trustee and the Company of such Reset Rate, whereupon the Company
shall notify the Depositary in writing of such Reset Rate.

       The Remarketing Agent's calculation of the Reset Rate shall be conclusive
and binding and the Trustee shall have no responsibility for the calculation
thereof.

       (iii) DEPOSITARY'S PROCEDURES, ETC.

       So long as the Corporate PIES, Treasury PIES or the Senior Notes are
evidenced by one or more Global Senior Notes deposited with the Depositary or
its nominee in writing of such Reset Rate, the Company shall request, not later
than 15 calendar days nor more than 30 Business Days prior to the Remarketing
Date, that the Depositary notify, directly or indirectly, each beneficial owner
of a Corporate PIES and of a Separated Senior Note of the impending Remarketing.

       In accordance with the Depositary's normal procedures, on the Remarketing
Settlement Date or the Purchase Contract Settlement Date, as applicable, the
transactions described above with respect to each Senior Note tendered for
purchase and sold in the Remarketing shall be executed through the Depositary,
and the accounts of the respective Depositary Participants shall be debited and
credited and such Senior Notes delivered by book entry as necessary to effect
purchases and sales of such Senior Notes. The Depositary shall make payment in
accordance with its normal procedure; PROVIDED that, the procedures set forth
herein, including provisions for payment by purchasers of the Senior Notes in
the Remarketing, shall be subject to modification to the extent required by the
Depositary or if the book-entry system is no longer available for the Senior
Notes at the time of the Remarketing, to facilitate the tendering and
remarketing of the Senior Notes in certificated form, and shall provide for the
authentication and delivery of Senior Notes in a principal amount equal to the
unremarketed portion of such Senior Notes. In addition, the Remarketing Agent
may modify, the settlement procedures set forth herein in order to facilitate
the settlement process.

       If any Holder of Senior Notes selling Senior Notes in the Remarketing
fails to deliver such Senior Notes, the direct or indirect Depositary
Participant of such selling Holder and of any other Person who was to have
purchased Senior Notes in the Remarketing may deliver to any

<Page>


such other Person an aggregate principal amount of Senior Notes that is less
than the aggregate principal amount of Senior Notes that otherwise was to be
purchased by such Person. In such event, the aggregate principal amount of
Senior Notes to be so delivered shall be determined by such direct or indirect
Depositary Participant, and delivery of such lesser aggregate principal amount
of Senior Notes shall constitute good delivery.

       (iv) OTHER MATTERS REGARDING REMARKETING.

       (A) The Remarketing Agent may purchase Remarketing Senior Notes for its
own account. However, under no circumstances, shall the Remarketing Agent be
obligated to purchase any Senior Notes in connection with a Remarketing and
neither the Company nor the Remarketing Agent shall be obligated to provide or
liable for any payment upon tender of Senior Notes in a Remarketing.

       (B) Under the Remarketing Agreement, the Company, in its capacity as
issuer of the Senior Notes, shall be liable for, and shall pay, any and all
costs and expenses incurred in connection with the Remarketing, other than the
Remarketing Fee.

       (C) Notwithstanding the Pledge and, if applicable, the delivery of
Separated Senior Notes to the Collateral Agent for Remarketing, in each case, as
set forth herein, the Company's obligation to pay interest, including any
accrued and unpaid interest, on all outstanding Senior Notes (whether then
comprising a part of Corporate PIES or as Separated Senior Notes) pursuant to
the Indenture shall remain unconditional and absolute.

       8. DEFAULT AND REMEDIES.

       If an Event of Default with respect to Senior Notes shall occur and be
continuing, the principal of the Senior Notes may be declared due and payable in
the manner and with the effect and consequent remedies to the Holders, in each
case, as provided in the Indenture.

       No Holder of any Senior Note shall have any right by virtue or by
availing of any provision of the Indenture to institute any action or proceeding
at law or in equity or in bankruptcy or otherwise upon or under or with respect
to the Indenture, or for the appointment of a trustee, receiver, liquidator,
custodian or other similar official or for any other remedy hereunder, unless
such Holder previously shall have given to the Trustee written notice of a
Continuing Event of Default and unless the Holders of not less than 25% in
aggregate principal amount of the Senior Notes then Outstanding shall have made
written request upon the Trustee to institute such action or proceedings in its
own name as Trustee hereunder and shall have offered to the Trustee such
reasonable indemnity as it may require against the costs, expenses and
liabilities to be incurred therein or thereby and the Trustee for 60 days after
its receipt of such notice, request and offer of indemnity shall have failed to
institute any such action or proceeding and the Holders of a majority in
principal amount of then Outstanding Senior Notes shall have not given the
Trustee a direction inconsistent with such request, it being understood and
intended, and being expressly covenanted by the Holders of every Senior Note
with every other Holder and the Trustee, that no one or more Holders of Senior
shall have any right in any manner whatever by virtue or by availing of any
provision of the Indenture to affect, disturb or prejudice the rights of any
other such Holder of Senior Notes, or to obtain or seek to obtain

<Page>


priority over or preference to any other such Holder or to enforce any right
under the Indenture, except in the manner herein provided and for the equal,
ratable and common benefit of all Holders of Senior Notes. For the protection
and enforcement of the provisions of the Indenture, each and every Holder and
the Trustee shall be entitled to such relief as can be given either at law or in
equity.

       9. TAX TREATMENT.

       The Company agrees, and by purchasing a beneficial ownership interest in
the Senior Notes each Holder of Senior Notes will be deemed to have agreed, for
United States federal income tax purposes (a) to treat the acquisition of a
Corporate PIES as the acquisition of a unit consisting of a stock purchase
contract and a senior note issued by the Company and to treat the Senior Notes
as indebtedness that is subject to Treas. Reg. Sec. 1.1275-4 (the "Contingent
Payment Regulations") and (b) to be bound by the Company's determination of the
"comparable yield" and "project payment schedule," within the meaning of the
Contingent Payment Regulations, with respect to the Senior Notes. The Company
has determined that the comparable yield is an annual rate of 8.12%, compounded
quarterly. Based on the comparable yield, the projected payment schedule per
senior note is $0.9802 for the period ending on February 15, 2002, $0.9913 for
each subsequent quarter ending on or prior to the initial remarketing date and
$1.0663 for each quarter ending after the initial remarketing date (which does
not include the payment of principal at maturity).

       10. AMENDMENT; SUPPLEMENTS; AND WAIVERS.

       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 Holders at any time by the Company and the Trustee
with the consent of the Holders of a majority in principal amount of the Senior
Notes then Outstanding. The Indenture also contains provisions permitting the
Holders of a majority in aggregate principal amount of the Senior Notes
Outstanding, on behalf of the Holders of all Senior Notes, to waive certain past
defaults under the Indenture and their consequences. Any such consent or waiver
by the Holder of this Senior Note shall be conclusive and binding upon such
Holder and upon all future Holders of this Senior Note and of any Senior Note
issued upon the registration of transfer hereof or in exchange therefor or in
lieu hereof, whether or not notation of such consent or waiver is made upon this
Senior Note.

       11. OBLIGATION ABSOLUTE AND UNCONDITIONAL.

       No reference herein to the Indenture and no provision of this Senior Note
or of the Indenture shall alter or impair the obligation of the Company, which
is absolute and unconditional, to pay the principal of, premium, if any, and
interest on this Senior Note at the times, place and rate, and in the coin or
currency, herein prescribed.

       12. SEVERABILITY.

       If any provision in this Senior Note is unenforceable in any
jurisdiction, then to the fullest extent permitted bylaw, (i) the other
provisions of this Senior Note shall remain in full force and effect in such
jurisdiction and shall be liberally construed in order to carry out the
intentions of

<Page>


the parties hereto as nearly as may be possible and (ii) the invalidity or
unenforceability of any provision of this Senior Note in any jurisdiction shall
not in any way affect the validity or enforceability of such provision any other
jurisdiction.

       13. GOVERNING LAW.

       THIS SENIOR NOTE SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH,
THE LAWS OF THE STATE OF NEW YORK.

       14. JURISDICTION; VENUE.

       The Company submits to the nonexclusive jurisdiction of the United States
District Court for the Southern District of New York and of any New York state
court sitting in New York City for the purposes of all legal proceedings arising
out of or relating to this Senior Note or the transactions contemplated hereby.
The parties hereto irrevocably waive, to the fullest extent permitted by
applicable law, any objection which they may now or hereafter have to the laying
of the venue of any such proceeding brought in such a court and any claim that
any such proceeding brought in such a court has been brought in an inconvenient
forum.

       15. COPIES OF THE INDENTURE.

       The Company will furnish to any Holder upon written request and without
charge a copy of the Indenture. Requests may be made to:

            Sierra Pacific Resources
            6100 Neil Road
            Reno, Nevada  89520-3150
            Attention:  Treasurer

<PAGE>


                                  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 rights of survivorship and not as
                        tenants in common

UNIF GIFT MIN ACT -     __________________ Custodian for __________________
                          (CUSTODIAN)                          (MINOR)

                        Under Uniform Gifts to Minors Act of

                        ------------------------------------
                                      (STATE)

Additional abbreviations may also be used though not on the above list.

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

       FOR VALUE RECEIVED, the undersigned hereby sell(s) and transfer(s) unto


--------------------------------------------------------------------------------
                            (INSERT NAME OF ASSIGNEE)


--------------------------------------------------------------------------------
 (INSERT SOCIAL SECURITY, TAXPAYER I.D. OR OTHER IDENTIFYING NUMBER OF ASSIGNEE)


--------------------------------------------------------------------------------
                          (INSERT ADDRESS OF ASSIGNEE)

the within Senior Note and all rights thereunder, hereby irrevocably
constituting and appointing


--------------------------------------------------------------------------------
agent to transfer said Senior Note on the books of Sierra Pacific Resources,
with full power of substitution in the premises.

Dated: _______________ __, _____         The Bank of New York,
                                         as Purchase Contract Agent



                                         By:
                                            ------------------------------------
                                            Barbara A. Bevelaqua
                                            Vice President

<Page>


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

                                         NOTICE: The signature to this
                                         assignment must correspond with the
                                         name as it appears upon the face of
                                         the within Corporate PIES Certificates
                                         in every particular, without alteration
                                         or enlargement or any change
                                         whatsoever.

                                         Signature Guarantee:
                                                             -------------------

NOTICE: THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME AS
WRITTEN UPON THE FACE OF THE WITHIN INSTRUMENT IN EVERY PARTICULAR WITHOUT
ALTERATION OR ENLARGEMENT, OR ANY CHANGE WHATEVER.

<PAGE>


                       SCHEDULE OF INCREASES OR DECREASES

       The following increases or decreases in this Senior Note have been made:

<Table>
<Caption>
----------------------------------------------------------------------------------------------------------------------------
                                                                                PRINCIPAL AMOUNT OF
                           AMOUNT OF DECREASE       AMOUNT OF INCREASE IN          SENIOR NOTES
                           IN PRINCIPAL AMOUNT       PRINCIPAL AMOUNT OF         EVIDENCED BY THE            SIGNATURE OF
                             OF SENIOR NOTES             SENIOR NOTES           GLOBAL SENIOR NOTE        AUTHORIZED OFFICER
                            EVIDENCED BY THE           EVIDENCED BY THE           FOLLOWING SUCH             OF TRUSTEE OR
          DATE             GLOBAL SENIOR NOTE         GLOBAL SENIOR NOTE       DECREASE OR INCREASE        COLLATERAL AGENT
----------------------------------------------------------------------------------------------------------------------------
<S>                       <C>                       <C>                        <C>                        <C>

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</Table>