<PAGE>

                                                                     Exhibit 4.2

                              [FORM OF GLOBAL NOTE]

                          [Form of Face of Global Note]

         UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF
THE DEPOSITORY TRUST COMPANY TO THE ISSUER OR ITS AGENT FOR REGISTRATION OF
TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE
NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (AND ANY PAYMENT HEREON IS MADE
TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY), ANY TRANSFER, PLEDGE OR OTHER
USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL SINCE THE
REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

         TRANSFERS OF THIS GLOBAL NOTE SHALL BE LIMITED TO TRANSFERS IN WHOLE,
BUT NOT IN PART, TO NOMINEES OF THE DEPOSITORY TRUST COMPANY, OR TO A SUCCESSOR
THEREOF OR SUCH SUCCESSOR'S NOMINEE AND TRANSFERS OF PORTIONS OF THIS GLOBAL
NOTE SHALL BE LIMITED TO TRANSFERS MADE IN ACCORDANCE WITH THE RESTRICTIONS SET
FORTH IN ARTICLE TWO OF THE INDENTURE REFERRED TO ON THE REVERSE HEREOF.

         THIS NOTE AND THE SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION OF
THIS NOTE HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED
(THE "SECURITIES ACT"), OR ANY STATE SECURITIES LAWS. NEITHER THIS NOTE, THE
SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION OF THIS NOTE NOR ANY INTEREST OR
PARTICIPATION HEREIN OR THEREIN MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED,
PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION
UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, REGISTRATION.

         THE HOLDER OF THIS NOTE, BY ITS ACCEPTANCE HEREOF, AGREES TO OFFER,
SELL, OR OTHERWISE TRANSFER SUCH NOTE, PRIOR TO THE DATE (THE "RESALE
RESTRICTION TERMINATION DATE"), WHICH IS TWO YEARS AFTER THE LATER OF THE
ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH SIERRA PACIFIC RESOURCES
(THE "COMPANY") OR ANY AFFILIATE OF THE COMPANY WAS THE OWNER OF THIS NOTE (OR
ANY PREDECESSOR OF SUCH NOTE) ONLY (A) TO THE COMPANY OR ANY SUBSIDIARY THEREOF,
(B) FOR SO LONG AS THIS NOTE AND THE SHARES OF COMMON STOCK ISSUABLE UPON
CONVERSION OF THIS NOTE ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A, TO A
PERSON IT REASONABLY BELIEVES IS A "QUALIFIED INSTITUTIONAL BUYER" AS DEFINED IN
RULE 144A UNDER THE SECURITIES ACT THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE
ACCOUNT OF A QUALIFIED

                                       1-1

<PAGE>

INSTITUTIONAL BUYER TO WHICH NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN
RELIANCE ON RULE 144A, (C) PURSUANT TO AN EXEMPTION FROM REGISTRATION PROVIDED
BY RULE 144 UNDER THE SECURITIES ACT, IF AVAILABLE, (D) PURSUANT TO A
REGISTRATION STATEMENT WHICH HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES
ACT AND CONTINUES TO BE EFFECTIVE AT THE TIME OF TRANSFER OR (E) IN AN OFFSHORE
TRANSACTION IN ACCORDANCE WITH RULE 904 OF REGULATION S UNDER THE SECURITIES
ACT. IF THE PROPOSED TRANSFER IS PURSUANT TO CLAUSES (C) OR (E) ABOVE, SUCH
TRANSFER IS SUBJECT TO THE COMPANY'S AND THE TRUSTEE'S RIGHTS PRIOR TO ANY SUCH
OFFER, SALE OR TRANSFER TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL,
CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO THE COMPANY, AND IN EACH
OF THE FOREGOING CASES, A CERTIFICATE OF TRANSFER IN THE FORM APPEARING ON THE
OTHER SIDE OF THIS NOTE IS COMPLETED AND DELIVERED BY THE TRANSFEROR TO THE
TRUSTEE. THE HOLDER AGREES THAT IT WILL DELIVER TO EACH PERSON TO WHOM THE
SECURITY EVIDENCED HEREBY IS TRANSFERRED (OTHER THAN PURSUANT TO CLAUSE D ABOVE)
A NOTICE SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND. THIS LEGEND WILL BE REMOVED
UPON THE REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE.

         [THE FOREGOING LEGEND MAY BE REMOVED FROM THIS NOTE ON SATISFACTION OF
THE CONDITIONS SPECIFIED IN THE INDENTURE.]

                                       1-2

<PAGE>

                            SIERRA PACIFIC RESOURCES
                        7.25% Convertible Notes due 2010

No.: 1                                                  CUSIP: 826428 AE 4
Issue Date:                                             ISIN: US826428AE48

         SIERRA PACIFIC RESOURCES, a Nevada corporation (the "Company"),
promises to pay to Cede & Co. or registered assigns, the principal sum of THREE
HUNDRED MILLION DOLLARS ($300,000,000) on February 14, 2010.

         This Note shall bear interest as specified on the other side of this
Note. This Note is convertible as specified on the other side of this Note.

         Additional provisions of this Note are set forth on the other side of
this Note.

                                      1-3

<PAGE>

         IN WITNESS WHEREOF, the Company has caused this Note to be signed
manually or by facsimile by its duly authorized officer.

Dated: February __, 2003                        SIERRA PACIFIC RESOURCES

                                                By_____________________________
                                                  Name:
                                                  Title:

TRUSTEE'S CERTIFICATE OF
 AUTHENTICATION

THE BANK OF NEW YORK,
as Trustee, certifies that this
is one of the Notes referred
to in the within-mentioned Indenture (as
defined on the other side of this Note).

By_____________________________
     Authorized Signatory

                                      1-4

<PAGE>

                         [Form of Reverse Side of Note]

                         7.25% Convertible Note due 2010

1.       Cash Interest.

         The Company promises to pay interest in cash on the principal amount of
         this Note at the rate per annum of 7.25%. The Company will pay cash
         interest semiannually in arrears on February 14 and August 14 of each
         year (each an "Interest Payment Date") to Holders of record at the
         close of business on January 31 and July 31 (whether or not a business
         day) (each a "Regular Record Date"), as the case may be, immediately
         preceding such Interest Payment Date. Cash interest on the Notes will
         accrue from the most recent date to which interest has been paid or
         duly provided or, if no interest has been paid, from the Issue Date.
         Cash interest will be computed on the basis of a 360-day year of twelve
         30-day months.

         In accordance with the terms of the Registration Rights Agreement,
         during the first 90 days following the day on which an Event (as
         defined in the Registration Rights Agreement) has occurred and is
         continuing, the Interest Rate borne by the Notes shall be increased by
         0.25% to 7.5% per annum. From and after the 91st day following the day
         on which an Event has occurred and such Event is continuing, the
         Interest Rate borne by the Notes shall be increased by an additional
         0.25% to 7.75% per annum. In no event shall the Interest Rate borne by
         the Notes exceed 7.75% per annum. Any amount of additional interest
         will be payable in cash semiannually, in arrears, on each Interest
         Payment Date and will cease to accrue on the date the Event is cured.
         The Holder of this Note is entitled to the benefits of the Registration
         Rights Agreement.

         The Holder of this Note is entitled to the benefits of the Pledge
         Agreement, dated February 14, 2003, between the Company and The Bank of
         New York (the "Trustee"), pursuant to which the Company has placed in
         the Pledge Account cash or Pledged Financial Assets sufficient to
         provide for the payment of the first five interest payments (up to and
         including the interest payment due on August 14, 2005) on this Note.
         The terms capitalized but undefined in this paragraph have the meanings
         given to them in the Pledge Agreement.

2.       Payment of Additional Interest Amounts.

In the event the Company declares a dividend on its Common Stock, the Company
shall pay to each Holder of record as of the record date for such dividend an
amount equal to the product of (i) such per share dividend declared by the
Company multiplied by (ii) the number of shares of Common Stock such Holder
would possess had such Holder converted its Notes into a number of shares of
Common Stock equal to the Conversion Rate as of the record date for such
dividend (each such payment an "Additional Interest Amount and, collectively the
"Additional Interest Amounts"); provided, however, that such amount shall not be
due and no payment with respect thereto shall be made with respect to the Notes
unless such dividend is paid to holders of Common Stock. The payment date for an
Additional Interest Amount shall be the same as the

                                       1-5

<PAGE>

payment date for the dividend to which the Additional Interest Amount relates.
Holders of Notes shall not be entitled to receive any Additional Interest Amount
with respect to any dividend that causes an adjustment to the Conversion Rate.

3.       Method of Payment.

Subject to the terms and conditions of the Indenture, the Company will make
payments in respect of the principal of, premium, if any, and cash interest on
this Note to a Paying Agent. In respect of Redemption Prices and Change of
Control Repurchase Prices, the Company will make payments in respect of the
principal of, premium, if any, and cash interest on this Note to Holders who
surrender Notes to a Paying Agent to collect such payments in respect of the
Notes. The Company will pay cash amounts in money of the United States that at
the time of payment is legal tender for payment of public and private debts.
However, the Company may make such cash payments by check payable in such money.
A holder of Notes with an aggregate principal amount in excess of $10,000,000
will be paid by wire transfer in immediately available funds at the election of
such holder. Any payment required to be made on any day that is not a Business
Day will be made on the next succeeding Business Day.

4.       Paying Agent, Conversion Agent and Registrar.

Initially, the Trustee will act as Paying Agent, Conversion Agent and Registrar.
The Company may appoint and change any Paying Agent, Conversion Agent, Registrar
or co-registrar without notice, other than notice to the Trustee, except that
the Company will maintain at least one Paying Agent in the State of New York,
The City of New York, and Borough of Manhattan, which shall initially be an
office or agency of the Trustee. The Company or any of its Subsidiaries or any
of their Affiliates may act as Paying Agent, Conversion Agent, Registrar or
co-registrar.

5.       Indenture.

         The Company issued the Notes under an Indenture dated as of February
         14, 2003 (the Indenture"), between the Company and the Trustee. The
         terms of the Notes include those stated in the Indenture and those made
         part of the Indenture by reference to the Trust Indenture Act of 1939,
         as in effect from time to time (the "TIA"). Capitalized terms used
         herein and not defined herein have the meanings ascribed thereto in the
         Indenture. The Notes are subject to all such terms, and Noteholders are
         referred to the Indenture and the TIA for a statement of those terms.

         The Notes are general unsecured obligations of the Company (except as
         provided in Article 12 of the Indenture) limited to $300,000,000
         aggregate principal amount. The Indenture does not limit other
         indebtedness of the Company, secured or unsecured.

6.       Redemption of the Notes at the Option of the Company.

At any time on or after February 14, 2008, the Company may redeem the Notes in
whole at any time or in part from time to time upon not less than 30 nor more
than 60 days' notice, at the following prices (expressed in percentages of the
principal amount) together with accrued but unpaid interest to, but excluding,
the date fixed for redemption. However, if a redemption date is

                                       1-6

<PAGE>

any interest payment date, the semi-annual payment of interest becoming due on
such date shall be payable to the holder of record as of the relevant record
date and the redemption price shall not include such interest payment.

         During the twelve months commencing February 14 of the years set forth
         below:

<TABLE>
<CAPTION>
                       Year                                   Redemption Price
                       ----                                   ----------------
<S>                                                           <C>
2008.....................................................          102.1%

2009.....................................................          101.0%
</TABLE>

         If the Company does not redeem all the Notes, the Trustee will select
         the Notes to be redeemed in principal amounts of $1,000 or integral
         multiples of $1,000 by lot or on a pro rata basis. If any Notes are to
         be redeemed in part only, a new Note or Notes in principal amount equal
         to the unredeemed principal portion thereof will be issued. If a
         portion of a Holder's Notes is selected for partial redemption and the
         Holder converts a portion of its Notes, the converted portion will be
         deemed to be taken from the portion selected for redemption.

         No sinking fund is provided for the Notes.

7.       Repurchase by the Company at the Option of the Holder.

If a Change of Control occurs, the Holder, at the Holder's option, shall have
the right, in accordance with the provisions of the Indenture, to require the
Company to repurchase the Notes (or any portion of the principal amount hereof
that is at least $1,000 or an integral multiple thereof, provided that the
portion of the principal amount of this Note to be outstanding after such
repurchase is at least equal to $1,000) at the Change of Control Repurchase
Price in cash, plus any interest accrued and unpaid to, but excluding, the
Change of Control Repurchase Date.

A Change of Control Repurchase Notice will be given by the Company to the
Holders as provided in the Indenture. To exercise a repurchase right, a Holder
must deliver to the Trustee a written notice as provided in the Indenture.

Holders have the right to withdraw any Change of Control Repurchase Notice by
delivering to the Paying Agent a written notice of withdrawal in accordance with
the provisions of the Indenture.

8.       Notice of Redemption.

         Notice of redemption will be mailed not less than 30 days but not more
         than 60 days before the Redemption Date to each Holder of Notes to be
         redeemed at the Holder's registered address. If money sufficient to pay
         the Redemption Price of all Notes (or portions thereof) to be redeemed
         on the Redemption Date is deposited with the Paying Agent prior to or
         on the Redemption Date, immediately after such Redemption Date interest
         ceases to accrue on such Notes or portions thereof. Notes in
         denominations

                                       1-7

<PAGE>

         larger than $1,000 of principal amount may be redeemed in part but only
         in integral multiples of $1,000 of principal amount.

9.       Conversion.

The Notes will not be convertible prior to August 14, 2003. At any time on or
after August 14, 2003, subject to and upon compliance with the provisions of the
Indenture, at the option of the Holder thereof, any Note or any portion of the
principal amount thereof which is $1,000 or an integral multiple of $1,000 may
be converted at the principal amount thereof, or of such portion thereof, into a
combination of cash and duly authorized, fully paid and nonassessable shares of
Common Stock (or, in the event that the Shareholder Approval Condition described
in the Indenture shall have been satisfied and the Company so elects, entirely
into shares of Common Stock) as provided in the Indenture. Such conversion right
shall expire at the close of business on February 14, 2010.

The "Conversion Rate" shall initially be 219.1637 and shall be adjusted in
certain instances as provided in the Indenture. The "Share Payment Component"
shall initially be 76.7073 and shall be subject to adjustment in the same manner
and under the same circumstances as the Conversion Rate, subject to any
limitation under applicable rules of the New York Stock Exchange.

         The Company shall pay a cash adjustment as provided in the Indenture in
         lieu of any fractional share of Common Stock.

         To convert a Note, a Holder must (1) complete and sign the conversion
         notice below (or complete and sign a facsimile of such notice) and
         deliver such notice to the Conversion Agent, (2) surrender the Note
         duly signed and endorsed to the Conversion Agent, (3) furnish
         appropriate endorsements and transfer documents if required by the
         Conversion Agent, the Company or the Trustee and (4) pay any transfer
         or similar tax or payment detailed below, if required.

         Notes surrendered for conversion, other than those called for
         redemption pursuant to paragraph 6 above, during the period from the
         close of business on any Regular Record Date to the opening of business
         on the next succeeding Interest Payment Date shall be accompanied by
         payment in New York Clearing House funds or other funds acceptable to
         the Company of an amount equal to the interest (including any
         Liquidated Damages Amounts or Additional Interest Amounts that would be
         due and payable on such Interest Payment Date) to be received on such
         Interest Payment Date on the principal amount of Notes being
         surrendered for conversion. No such payment will be required if the
         Notes are called for redemption pursuant to paragraph 6 above.

10.      Conversion Arrangement on Call for Redemption.

         Any Notes called for redemption, unless surrendered for conversion
         before the close of business on the Redemption Date, may be deemed to
         be purchased from the Holders of such Notes at an amount not less than
         the Redemption Price, by one or more investment bankers or other
         purchasers who may agree with the Company to purchase such Notes

                                       1-8

<PAGE>

         from the Holders, to convert them into Common Stock of the Company and
         to make payment for such Notes to the Trustee in trust for such
         Holders.

11.      Denominations; Transfer; Exchange.

The Notes are in fully registered form, without coupons, in denominations of
$1,000 of principal amount and integral multiples of $1,000. A Holder may
transfer or exchange Notes in accordance with the Indenture. The Registrar may
require a Holder, among other things, to furnish appropriate endorsements and
transfer documents and to pay any taxes and fees required by law or permitted by
the Indenture. The Registrar need not transfer or exchange (i) any Notes
selected for redemption (except, in the case of a Note to be redeemed in part,
the portion of the Note not to be redeemed), (ii) any Notes in respect of which
a Change of Control Repurchase Notice has been given and not withdrawn (except,
in the case of a Note to be purchased in part, the portion of the Note not to be
purchased) or (iii) any Notes for a period of 15 days before the mailing of a
notice of redemption of Notes to be redeemed.

12.      Persons Deemed Owners.

The registered Holder of this Note may be treated as the owner of this Note for
all purposes.

13.      Unclaimed Money or Notes.

         The Trustee and the Paying Agent shall return to the Company upon
         written request any money or Notes held by them for the payment of any
         amount with respect to the Notes that remains unclaimed for two years,
         subject to applicable unclaimed property law. After return to the
         Company, Holders entitled to the money or Notes must look to the
         Company for payment as general creditors unless an applicable abandoned
         property law designates another person.

14.      Amendment; Waiver.

Subject to certain exceptions set forth in the Indenture, (i) the Indenture or
the Notes may be amended with the written consent of the Holders of at least a
majority in aggregate principal amount of the Notes at the time outstanding and
(ii) certain Defaults may be waived with the written consent of the Holders of a
majority in aggregate principal amount of the Notes at the time outstanding.
Subject to certain exceptions set forth in the Indenture, without the consent of
any Noteholder, the Company and the Trustee may amend the Indenture or the Notes
to cure any ambiguity, omission, defect or inconsistency, or to comply with
Article 5 of the Indenture, to make any change that does not adversely affect
the rights of any Noteholder, or to comply with any requirement of the SEC in
connection with the qualification of the Indenture under the TIA.

15.      Defaults and Remedies.

Under the Indenture, Events of Default include (1) the Company fails to pay when
due the principal of or premium, if any, on any of the Notes at maturity, upon
redemption or exercise of a repurchase right or otherwise; (2) the Company fails
to pay an installment of interest (including Liquidated Damages Amounts and
Additional Interest Amounts, if any) on any of the Notes that continues for 30
days after the date when due, provided that a failure to make or provide for the

                                       1-9

<PAGE>

payment of any of the first five scheduled interest payments on the Notes within
3 Business Days after an Interest Payment Date will constitute an Event of
Default with no additional grace or cure period; (3) the Company fails to (A)
deliver shares of Common Stock, together with cash in lieu of fractional shares,
when such Common Stock or cash in lieu of fractional shares is required to be
delivered upon conversion of a Note, or (B) make payment of the Cash Payment
Component when such cash is required to be delivered upon conversion of a Note,
and, in each case, that failure continues for 10 days after the relevant
delivery date; (4) the Company fails to perform or observe any other term,
covenant or agreement contained in the Notes or the Indenture for a period of 60
days after written notice of such failure, requiring the Company to remedy the
same, shall have been given to the Company by the Trustee or to the Company and
the Trustee by the Holders of at least 25% in aggregate principal amount of the
Notes then outstanding; (5) (A) the Company or any Significant Subsidiary fails
to pay at maturity (after giving effect to any applicable grace period) any
Indebtedness in an aggregate principal amount in excess of $10 million or (B)
any of the Company's Indebtedness, or Indebtedness of any Significant
Subsidiary, aggregating $10 million or more shall have been accelerated and
declared due and payable prior to the scheduled maturity thereof, and such
acceleration is not rescinded or annulled within a 30-day period after the date
of such acceleration; (6) certain events of bankruptcy, insolvency or
reorganization with respect to the Company or any Significant Subsidiary; and
(7) the Pledge Agreement shall cease to be in full force and effect or
enforceable in accordance with its terms, prior to the termination thereof in
accordance with Section 18 of the Pledge Agreement. If an Event of Default
(other than an Event of Default specified in clause (6) above) occurs and is
continuing, the Trustee, or the Holders of at least 25% in aggregate principal
amount of the Notes at the time outstanding, may declare all the Notes to be due
and payable immediately. Certain events of bankruptcy or insolvency are Events
of Default which will result in the Notes becoming due and payable immediately
upon the occurrence of such Events of Default.

         Noteholders may not enforce the Indenture or the Notes except as
         provided in the Indenture. The Trustee may refuse to enforce the
         Indenture or the Notes unless it receives reasonable indemnity or
         security. Subject to certain limitations, Holders of a majority in
         aggregate principal amount of the Notes at the time outstanding may
         direct the Trustee in its exercise of any trust or power. The Trustee
         may withhold from Noteholders notice of any continuing Default (except
         a Default in payment of amounts specified in clause (1) or (2) above)
         if it determines that withholding notice is in their interests.

16.      Trustee Dealings with the Company.

Subject to certain limitations imposed by the TIA, the Trustee under the
Indenture, in its individual or any other capacity, may become the owner or
pledgee of Notes and may otherwise deal with and collect obligations owed to it
by the Company or its Affiliates and may otherwise deal with the Company or its
Affiliates with the same rights it would have if it were not Trustee.

17.      No Recourse Against Others.

A director, officer, employee or stockholder, as such, of the Company shall not
have any liability for any obligations of the Company under the Notes or the
Indenture or for any claim based on,

                                      1-10

<PAGE>

in respect of or by reason of such obligations or their creation. By accepting a
Note, each Noteholder waives and releases all such liability. The waiver and
release are part of the consideration for the issue of the Notes.

18.      Authentication.

This Note shall not be valid until an authorized signatory of the Trustee signs
the Trustee's Certificate of Authentication on the other side of this Note.

19.      Abbreviations.

Customary abbreviations may be used in the name of a Noteholder or an assignee,
such as TEN COM (=tenants in common), TEN ENT (=tenants by the entireties), JT
TEN (=joint tenants with right of survivorship and not as tenants in common),
CUST (=custodian), and U/G/M/A (=Uniform Gift to Minors Act).

20.      GOVERNING LAW.

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

         The Company will furnish to any Noteholder upon written request and
without charge a copy of the Indenture which has in it the text of this Note in
larger type.

                                      1-11

<PAGE>

<TABLE>
<CAPTION>
              ASSIGNMENT FORM                                      CONVERSION NOTICE
<S>                                                    <C>
To assign this Note, fill in the form below:           To convert this Note into Common Stock of
                                                       the Company, check the box:
I or we assign and transfer this Note to
                                                       To convert only part of this Note, state the
______________________________________________         principal amount to be converted (which
______________________________________________         must be $1,000 or an integral multiple of
                                                       $1000):
(Insert assignee's social security or tax ID
no.)                                                   $________________________

______________________________________________         If you want the stock certificate made out in
                                                       another person's name, fill in the form
______________________________________________         below:

______________________________________________         _____________________________________________
(Print or type assignee's name, address and
zip code)                                              _____________________________________________
                                                       (Insert other person's social security or tax
and irrevocably appoint                                ID no.)

_____________________ agent to transfer                _____________________________________________
this Note on the books of the Company. The
agent may substitute another to act for him.           _____________________________________________

                                                       _____________________________________________

                                                       _____________________________________________
                                                       (Print or type other person's name, address
                                                       and zip code)
</TABLE>

________________________________________________________________________________

Date: ______________________  Your Signature: __________________________________

________________________________________________________________________________
       (Sign exactly as your name appears on the other side of this Note)

                               SIGNATURE GUARANTEE

Signatures must be guaranteed by an "eligible guarantor institution" meeting the
requirements of the Registrar, which requirements include membership or
participation in the Security Transfer Agent Medallion Program ("STAMP") or such
other "signature guarantee program" as may be determined by the Registrar in
addition to, or in substitution for, STAMP, all in accordance with the
Securities Exchange Act of 1934, as amended.

                                      1-12

<PAGE>

                       [Form of Face of Certificated Note]

         THIS NOTE AND THE SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION OF
THIS NOTE HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED
(THE "SECURITIES ACT"), OR ANY STATE SECURITIES LAWS. NEITHER THIS NOTE, THE
SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION OF THIS NOTE NOR ANY INTEREST OR
PARTICIPATION HEREIN OR THEREIN MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED,
PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION
OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, REGISTRATION.

         THE HOLDER OF THIS NOTE, BY ITS ACCEPTANCE HEREOF, AGREES TO OFFER,
SELL, OR OTHERWISE TRANSFER SUCH NOTE, PRIOR TO THE DATE (THE "RESALE
RESTRICTION TERMINATION DATE"), WHICH IS TWO YEARS AFTER THE LATER OF THE
ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH SIERRA PACIFIC RESOURCES
(THE "COMPANY") OR ANY AFFILIATE OF THE COMPANY WAS THE OWNER OF THIS NOTE (OR
ANY PREDECESSOR OF SUCH NOTE) ONLY (A) TO THE COMPANY OR ANY SUBSIDIARY THEREOF,
(B) FOR SO LONG AS THIS NOTE AND THE SHARES OF COMMON STOCK ISSUABLE UPON
CONVERSION OF THIS NOTE ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A, TO A
PERSON IT REASONABLY BELIEVES IS A "QUALIFIED INSTITUTIONAL BUYER" AS DEFINED IN
RULE 144A UNDER THE SECURITIES ACT THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE
ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHICH NOTICE IS GIVEN THAT THE
TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (C) PURSUANT TO AN EXEMPTION
FROM REGISTRATION PROVIDED BY RULE 144 UNDER THE SECURITIES ACT, IF AVAILABLE,
(D) PURSUANT TO A REGISTRATION STATEMENT WHICH HAS BEEN DECLARED EFFECTIVE UNDER
THE SECURITIES ACT AND CONTINUES TO BE EFFECTIVE AT THE TIME OF TRANSFER OR (E)
IN AN OFFSHORE TRANSACTION IN ACCORDANCE WITH RULE 904 OF REGULATION S UNDER THE
SECURITIES ACT IF THE PROPOSED TRANSFER IS PURSUANT TO CLAUSES (C) OR (E) ABOVE,
SUCH TRANSFER IS SUBJECT TO THE COMPANY'S AND THE TRUSTEE'S RIGHTS PRIOR TO ANY
SUCH OFFER, SALE OR TRANSFER TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL,
CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO THE COMPANY, AND IN EACH
OF THE FOREGOING CASES, A CERTIFICATE OF TRANSFER IN THE FORM APPEARING ON THE
OTHER SIDE OF THIS NOTE IS COMPLETED AND DELIVERED BY THE TRANSFEROR TO THE
TRUSTEE. THE HOLDER AGREES THAT IT WILL DELIVER TO EACH PERSON TO WHOM THE
SECURITY EVIDENCED HEREBY IS TRANSFERRED (OTHER THAN PURSUANT TO CLAUSE D ABOVE)
A NOTICE SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND. THIS LEGEND WILL BE REMOVED
UPON THE REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE.

         [THE FOREGOING LEGEND MAY BE REMOVED FROM THIS NOTE ON SATISFACTION OF
THE CONDITIONS SPECIFIED IN THE INDENTURE.]

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<PAGE>

                            SIERRA PACIFIC RESOURCES
                        7.25% Convertible Notes due 2010

No.:                                                            CUSIP:
Issue Date:

         SIERRA PACIFIC RESOURCES, a Nevada corporation (the "Company"),
promises to pay to Cede & Co. or registered assigns, the principal sum of
___________ DOLLARS ($___________) on February 14, 2010.

         This Note shall bear interest as specified on the other side of this
Note. This Note is convertible as specified on the other side of this Note.

         Additional provisions of this Note are set forth on the other side of
this Note.

Dated:

                                                 SIERRA PACIFIC RESOURCES

                                                 By_____________________________
                                                   Name:
                                                   Title:

TRUSTEE'S CERTIFICATE OF
  AUTHENTICATION

THE BANK OF NEW YORK,
as Trustee, certifies that this
is one of the Notes referred
to in the within-mentioned Indenture (as
defined on the other side of this Note).

By_____________________________
     Authorized Signatory

Dated: ____________________

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