<PAGE>

                                                                 EXHIBIT 4(b)(5)

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

                                    FORM OF
                        SUPPLEMENTAL INDENTURE NO. [___]

                                      FROM

                              NORTHERN STATES POWER
                                     COMPANY
                            (A MINNESOTA CORPORATION)

                                       TO

                           WELLS FARGO BANK MINNESOTA,
        NATIONAL ASSOCIATION (FORMERLY, NORWEST BANK MINNESOTA, NATIONAL
                                  ASSOCIATION)

                                     TRUSTEE

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

                                   DATED AS OF

                                 [_____________]

                            SUPPLEMENTAL TO INDENTURE
                            DATED AS OF JULY 1, 1999

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

<PAGE>

                               TABLE OF CONTENTS

<TABLE>
<S>               <C>                                                                           <C>
PARTIES           ............................................................................  1

RECITALS          ............................................................................  1

                                   ARTICLE ONE
                       RELATION TO INDENTURE; DEFINITIONS

SECTION 1.01      Integral Part of Indenture..................................................  2
SECTION 1.02      (a)      Definitions........................................................  2
                  (b)      References to Articles and Sections................................  2
                  (c)      Terms Referring to this Supplemental Indenture.....................  2

                                   ARTICLE TWO
                       [_____]% NOTES, SERIES DUE [______]

SECTION 2.01      Designation and Principal Amount............................................  2
SECTION 2.02      Stated Maturity Date........................................................  2
SECTION 2.03      Interest Payment Dates......................................................  2
SECTION 2.04      Office for Payment..........................................................  3
SECTION 2.05      Optional Redemption Provisions..............................................  3
SECTION 2.06      Mandatory Redemption Provisions...............................................4
SECTION 2.07      Authorized Denominations....................................................  5
SECTION 2.08      Form of [_____]% Notes, Series Due [_______] ...............................  5

                                  ARTICLE THREE
                                    COVENANTS

SECTION 3.01      Limitation on Liens.........................................................  5
SECTION 3.02      Certain Definitions.........................................................  6

                                  ARTICLE FOUR
                                  MISCELLANEOUS

SECTION 4.01      Recitals of fact, except as stated, are statements
                  of the Company..............................................................  8
SECTION 4.02      Supplemental Indenture to be construed as a part
                  of the Indenture............................................................  8
SECTION 4.03      (a)      Trust Indenture Act to control.....................................  8
                  (b)      Severability of provisions contained in
                           Supplemental Indenture and Notes...................................  9
SECTION 4.04      References to either party in Supplemental Indenture
                  include successors or assigns...............................................  9
SECTION 4.05      (a)      Provision for execution in counterparts............................  9
                  (b)      Table of Contents and descriptive headings
                           of Articles not to affect meaning..................................  9
</TABLE>

Exhibit A - Form of [_______]% Notes, Series due [_______]

                                       i

<PAGE>

         SUPPLEMENTAL INDENTURE No. [___], made as of the [_______] day of
[________________], by and between NORTHERN STATES POWER COMPANY, a corporation
duly organized and existing under the laws of the State of Minnesota (the
"Company"), and WELLS FARGO BANK MINNESOTA, NATIONAL ASSOCIATION, a national
banking association organized and existing under the laws of the United States,
as trustee (the "Trustee"):

WITNESSETH:

         WHEREAS, Xcel Energy Inc., the parent corporation of the Company ("Xcel
Energy"), has heretofore executed and delivered an Indenture (hereinafter
referred to as the "Original Indenture"), made as of July 1, 1999;

         WHEREAS, Xcel Energy has heretofore executed and delivered a
Supplemental Indenture No. 1 ("Supplemental Indenture No. 1"), made as of July
15, 1999, which created a series of Securities designated "6.875% Senior Notes,
Series due 2009";

         WHEREAS, Xcel Energy has heretofore executed and delivered a
Supplemental Indenture No. 2 ("Supplemental Indenture No. 2"), made as of August
18, 2000, pursuant to which the Company assumed all of the obligations of Xcel
Energy under the Indenture (as defined below) and Xcel Energy conveyed all of
its rights and obligations under the Indenture to the Company;

         WHEREAS, Xcel Energy has heretofore executed and delivered a
Supplemental Indenture No. 3 ("Supplemental Indenture No. 3" and, collectively
with the Original Indenture, Supplemental Indenture No. 1 and Supplemental
Indenture No. 2, the "Indenture"), made as of July 1, 2002, which created a
series of Securities designated "8.00% Notes, Series due 2042";

         WHEREAS, Section 2.5 of the Original Indenture provides that Securities
shall be issued in series and that a Company Order shall specify the terms of
each series;

         WHEREAS, the Company has this day delivered a Company Order setting
forth the terms of a series of Securities designated "[_____]% Notes, Series due
[_______]" (hereinafter sometimes referred to as the "Notes due [_______]");

         WHEREAS, Section 12.1 of the Original Indenture provides that the
Company and the Trustee may enter into indentures supplemental thereto for the
purposes, among others, of establishing the form of Securities or establishing
or reflecting any terms of any Security and adding to the covenants of the
Company; and

         WHEREAS, the execution and delivery of this Supplemental Indenture No.
[___] (herein, "this Supplemental Indenture") have been duly authorized by a
resolution adopted by the Board of Directors of the Company (the "Board").

                                       1

<PAGE>

NOW, THEREFORE, THIS INDENTURE WITNESSETH:

         That in order to set forth the terms and conditions upon which the
Notes due [_______] are, and are to be, authenticated, issued and delivered, and
in consideration of the premises of the purchase and acceptance of the Notes due
[_______] by the Holders thereof and the sum of one dollar duly paid to it by
the Trustee at the execution of this Supplemental Indenture, the receipt whereof
is hereby acknowledged, the Company covenants and agrees with the Trustee for
the equal and proportionate benefit of the respective Holders from time to time
of the Notes due [_______] as follows:

                                   ARTICLE ONE
                       RELATION TO INDENTURE; DEFINITIONS

         SECTION 1.01      This Supplemental Indenture constitutes an integral
part of the Indenture.

         SECTION 1.02      For all purposes of this Supplemental Indenture:

         (a)      Capitalized terms used herein without definition shall have
                  the meanings specified in the Indenture;

         (b)      All references herein to Articles and Sections, unless
                  otherwise specified, refer to the corresponding Articles and
                  Sections of this Supplemental Indenture; and

         (c)      The terms "hereof," "herein," "hereby," "hereto," "hereunder"
                  and "herewith" refer to this Supplemental Indenture.

                                  ARTICLE TWO
                     [_______]% NOTES, SERIES DUE [_______]

         SECTION 2.01      There shall be a series of Securities designated the
"[_______]% Notes, Series due [_______]" (the "Notes due [_______]"). The Notes
due [_______] shall be limited to $[_______] aggregate principal amount.

         SECTION 2.02      Except as otherwise provided in Section 2.05 hereof,
the principal amount of the Notes due [_______] shall be payable on the stated
maturity date of [_______], [_______].

         SECTION 2.03      The Notes due [_______] shall be dated their date of
authentication as provided in the Indenture and shall bear interest from their
date at the rate of [_______]% per annum, payable on  [_______] and
[_______] of each year, commencing [_______], [_______]. If any such interest
payment date falls on a day that is not a business day, then payment of interest
will be made on the next succeeding business day, except that, if such business
day is in the next

                                       2

<PAGE>

succeeding calendar year, such payment shall be made on the immediately
preceding business day, in each case with the same force and effect as if made
on such date. Notwithstanding the definition of "Business Day" contained in the
Indenture, for purposes of this section, "business day" means a day other than
(1) a Saturday or a Sunday, (2) a legal holiday or a day on which banking
institutions in New York, New York are authorized or obligated by law or
executive order to close, or (3) a day on which the Trustee's Corporate Trust
Office is closed for business. The Regular Record Dates with respect to such
[_______], [_______], [_______] and [_______] interest payment dates shall be
[_______], [_______], [_______] and [_______], respectively. Except as otherwise
provided in this Section 2.03, principal and interest shall be payable to the
persons and in the manner provided in Sections 2.4 and 2.12 of the Indenture.

         SECTION 2.04      The Notes due [_______] shall be payable at the
corporate trust office of the Trustee, at the New York corporate trust office of
Wells Fargo Bank Minnesota, National Association, as co-paying agent, and at the
offices of such other paying agents as the Company may appoint by Company Order
in the future.

         SECTION 2.05      [The Company may not redeem the Notes due [_______]
prior to their stated maturity.] [The Company may redeem the Notes due [_______]
at any time, in whole or in part, at a redemption price equal to the greater of
(i) the principal amount of such Notes due [_______] to be redeemed or (ii) the
sum of the present value of the remaining scheduled payments of principal and
interest thereon, discounted to the date of redemption on a semi-annual basis
(assuming a 360-day year consisting of twelve 30-day months) at a Treasury Yield
(as defined below) plus [_______] basis points, plus in each case accrued
interest thereon to the date of redemption].

         "Treasury Yield" means, with respect to any redemption date, the rate
per annum equal to the semiannual equivalent yield to maturity of the Comparable
Treasury Issue, assuming a price for the Comparable Treasury Issue (expressed as
a percentage of its principal amount) equal to the Comparable Treasury Price for
the redemption date.

         "Comparable Treasury Issue" means the United States Treasury security
selected by an Independent Investment Banker as having a maturity comparable to
the remaining term of the Notes due [_______] that would be utilized, at the
time of selection and in accordance with customary financial practice, in
pricing new issues of corporate debt securities of comparable maturity to the
remaining term of the Notes.

         "Independent Investment Banker" means [_______] or its successor or, if
such firm is unwilling or unable to select the Comparable Treasury Issue, one of
the remaining Reference Treasury Dealers appointed by the Trustee after
consultation with the Company.

         "Comparable Treasury Price" means, with respect to any redemption date,
(i) the average of the bid and asked prices for the Comparable Treasury Issue
(expressed in each case as a percentage of its principal amount) on the third
business day preceding such redemption date, as set forth in the daily
statistical release (or any successor release)

                                       3

<PAGE>

published by the Federal Reserve Bank of New York and designated "Composite 3:30
p.m. Quotations for U.S. Government Securities" or (ii) if that release (or any
successor release) is not published or does not contain such prices on such
business day, (A) the average of the Reference Treasury Dealer Quotations for
such redemption date, after excluding the highest and lowest such Reference
Treasury Dealer Quotations for such redemption date, or (B) if fewer than four
such Reference Treasury Dealer Quotations are obtained, then the average of all
such Quotations.

         "Reference Treasury Dealer Quotations" means, with respect to each
Reference Treasury Dealer and any redemption date, the average, as determined by
the Trustee, of the bid and asked prices for the Comparable Treasury Issue
(expressed in each case as a percentage of its principal amount) quoted in
writing to the Trustee by such Reference Treasury Dealer at 5:00 p.m. on the
third business day preceding such redemption date.

         "Reference Treasury Dealer" means (i) each of [____________________]
and any other primary U.S. Government Securities dealer in New York City (a
"Primary Treasury Dealer") designated by, and not affiliated with,
[____________________], provided, however, that if [____________________], or
any of its designees shall cease to be a Primary Treasury Dealer, the Company
shall substitute another Primary Treasury Dealer as a substitute for such entity
and (ii) any other Primary Treasury Dealer selected by the Company.]

         [On or after [_______], the Company may redeem the Notes due [_______]
at any time, in whole or in part, at a redemption price equal to the principal
amount of such Notes due [_______], plus accrued interest to the date of
redemption.]

         The Notes due [_______] shall not be subject to any sinking fund.

         SECTION 2.06      [The Notes due [_______] will be repayable on
[_______], at the option of the holders thereof, at 100% of their principal
amount, together with accrued and unpaid interest to [_______]. In order for a
Note due [_______] to be repaid, the Company must receive at the corporate trust
office of the Trustee during the period from and including [_______] to and
including the close of business on [_______] (or if [_______] is not a Business
Day, the next succeeding Business Day): (i) a Note due [_______] with the form
entitled "Option to Elect Repayment" on the Note due [_______] duly completed,
or (ii) a telegram, telex, facsimile transmission or letter from a member of a
national securities exchange or the National Association of Securities Dealers,
Inc. or a commercial bank or a trust company in the United States of America
setting forth the name of the Holder of the Note due [_______], the principal
amount of the Note due [_______], the principal amount of the Note due ____ to
be repaid, a statement that the option to elect repayment is being exercised
thereby and a guarantee that the Note due [_______] to be repaid (with the form
entitled "Option to Elect Repayment" on the Note due [_______] duly completed)
will be received at the Trustee's corporate trust office, no later than five
Business Days after the date of such telegram, telex, facsimile transmission or
letter and such Note due [_______] and form duly completed are received at the
Trustee's office, by such fifth Business Day. Effective exercise of the
repayment option by the holder of any Note due [_______] shall be irrevocable.
No transfer or exchange of any Note due [_______] (or, in the event that any
Note due [_______] is to be repaid in part, such portion of the Note due
[_______] to be repaid) will be permitted after exercise of the repayment
option. The repayment option

                                       4

<PAGE>

may be exercised by the Holder of a Note due [_______] for less than the entire
principal amount of the Note due [_______], provided the principal amount which
is to be repaid is set forth on the form entitled "Option to Elect Repayment" on
the Note due [_______] and is equal to $1,000 or any integral multiple thereof.
All questions as to the validity, eligibility (including time of receipt) and
acceptance of any Note due [_______] for repayment will be determined by the
Company, whose determination will be final, binding and non-appealable. Upon
timely delivery of a Note due [_______] to the Trustee with the "Option to Elect
Repayment" form completed in accordance with the foregoing, the outstanding
principal amount of such Note due [_______] (or portion thereof indicated on the
"Option to Elect Repayment") shall become due and payable on [_______], at a
price equal to [_______]% of the principal amount to be repaid plus accrued and
unpaid interest to [_______].]

         SECTION 2.07      The Notes due [_______] shall be issued in fully
registered form without coupons in denominations of $1,000 and integral
multiples thereof.

         SECTION 2.08      The Notes due [_______] shall initially be in the
form attached as Exhibit A hereto.

                                  ARTICLE THREE
                                    COVENANTS

         SECTION 3.01      So long as there remain outstanding any Notes due
[_______], the Company will not create or suffer to be created or to exist any
mortgage, pledge, security interest, or other lien (collectively, "Lien") on any
of its utility properties or assets now owned or hereafter acquired to secure
any indebtedness, without making effective provision whereby the Notes due
[_______] shall be equally and ratably secured with any and all such
indebtedness and with any other indebtedness similarly entitled to be equally
and ratably secured. However, this restriction shall not apply to or prevent the
creation or existence of:

         (1)      the Mortgage securing the Company's First Mortgage Bonds or
                  any indenture supplemental thereto subjecting any property to
                  the Lien thereof or confirming the Lien thereof upon any
                  property, whether now owned or hereafter acquired;

         (2)      Liens on property existing at the time of acquisition or
                  construction of such property (or created within one year
                  after completion of such acquisition or construction), whether
                  by purchase, merger, construction or otherwise or to secure
                  the payment of all or any part of the purchase price or
                  construction cost thereof, including the extension of any such
                  Liens to repairs, renewals, replacements, substitutions,
                  betterments, additions, extensions and improvements then or
                  thereafter made on the property subject thereto;

                                       5

<PAGE>

         (3)      any extensions, renewals or replacements (or successive
                  extensions, renewals or replacements), in whole or in part, of
                  Liens permitted by the foregoing clauses (1) and (2);

         (4)      the pledge of any bonds or other securities at any time issued
                  under any of the Liens permitted by clauses (1), (2) or (3);

         (5)      Permitted Encumbrances; or

         (6)      Liens on property of any of the Company's subsidiaries,
                  including United Power and Land Co., First Midwest Auto Park
                  Inc., NSP Nuclear Corporation and NSP Financing I.

         Further, this restriction shall not apply to or prevent the creation or
existence of leases made, or existing on property acquired, in the ordinary
course of business.

         SECTION 3.02      Certain Definitions.

         "Mortgage" means the lien of the first mortgage pursuant to the Trust
Indenture, dated as of February 1, 1937, from the Company to BNY Midwest Trust
Company, as successor trustee, as supplemented by the supplemental trust
indenture, including the Supplemental and Restated Trust Indenture, dated as of
May 1, 1988 (the "First Mortgage Indenture"), securing the Company's First
Mortgage Bonds.

         "Permitted Encumbrances" means any of the following:

         (1)      Liens of taxes, assessments or governmental charges for the
                  then current year and taxes, assessments or governmental
                  charges not then delinquent; Liens for workers' compensation
                  awards and similar obligations not then delinquent;
                  mechanics', laborers', material men's and similar Liens not
                  then delinquent; and any of such Liens, whether or not
                  delinquent, whose validity is at the time being contested in
                  good faith by the Company;

         (2)      Liens and charges incidental to construction or current
                  operations which have not at the time been filed or asserted
                  or the payment of which has been adequately secured or which,
                  in the opinion of counsel, are not material in amount;

         (3)      Liens, securing obligations neither assumed by the Company nor
                  on account of which any of them customarily pays interest
                  directly or indirectly, existing, either at the date hereof,
                  or, as to property hereafter acquired, at the time of
                  acquisition by the Company;

         (4)      Any right which any municipal or governmental body or agency
                  may have by virtue of any franchise, license, contract or
                  statute to purchase, or designate a purchaser of or order the
                  sale of, any property of the Company upon payment of
                  reasonable compensation therefor, or to terminate any

                                       6

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                  franchise, license or other rights or to regulate the property
                  and business of the Company;

         (5)      The Lien of judgments covered by insurance, or upon appeal and
                  covered, if necessary, by the filing of an appeal bond, or if
                  not so covered not exceeding at any one time $1,000,000 in
                  aggregate amount;

         (6)      Easements or reservations in respect of any property of the
                  Company for the purpose of roads, pipelines, utility
                  transmission and distribution lines or other rights-of-way and
                  similar purposes, zoning ordinances, regulations,
                  reservations, restrictions, covenants, party wall agreements,
                  conditions of record and other encumbrances (other than to
                  secure the payment of money), none of which in the opinion of
                  counsel are such as to interfere with the proper operation and
                  development of the property affected thereby in the business
                  of the Company for the use intended;

         (7)      Any Lien or encumbrance, moneys sufficient for the discharge
                  of which have been deposited in trust with the Trustee
                  hereunder or with the trustee or mortgagee under the
                  instrument evidencing such Lien or encumbrance, with
                  irrevocable authority to the Trustee hereunder or to such
                  other trustee or mortgagee to apply such moneys to the
                  discharge of such Lien or encumbrance to the extent required
                  for such purpose;

         (8)      Any defects of title and any terms, conditions, agreements,
                  covenants, exceptions and reservations expressed or provided
                  in deeds or other instruments, respectively, under and by
                  virtue of which the Company has acquired any property or shall
                  hereafter acquire any property, none of which, in the opinion
                  of counsel, materially adversely affects the operation of the
                  properties of the Company;

         (9)      The pledge of cash or marketable securities for the purpose of
                  obtaining any indemnity, performance or other similar bonds in
                  the ordinary course of business, or as security for the
                  payment of taxes or other assessments being contested in good
                  faith, or for the purpose of obtaining a stay or discharge in
                  the course of any legal proceedings;

         (10)     The pledge or assignment in the ordinary course of business of
                  electricity, gas (either natural or artificial) or steam,
                  accounts receivable or customers' installment paper;

         (11)     Rights reserved to or vested in others to take or receive any
                  part of the electricity, gas (either natural or artificial),
                  steam or any by-products thereof generated or produced by or
                  from any properties of the Company or with respect to any
                  other rights concerning electricity, gas (either natural or
                  artificial) or steam supply, transportation, or storage which
                  are

                                       7

<PAGE>

                  in use in the ordinary course of the electricity, gas (either
                  natural or artificial) or steam business;

         (12)     Any landlord's Lien;

         (13)     Liens created or assumed by the Company in connection with the
                  issuance of debt securities, the interest on which is
                  excludable from the gross income of the holders of such
                  securities pursuant to Section 103 of the Internal Revenue
                  Code of 1986, or any successor section, for purposes of
                  financing, in whole or in part, the acquisition or
                  construction of property to be used by the Company, but such
                  Liens shall be limited to the property so financed (and the
                  real estate on which such property is to be located);

         (14)     Liens affixing to property of the Company at the time a Person
                  consolidates with or merges into, or transfers all or
                  substantially all of its assets to, the Company, provided that
                  in the opinion of the Board or Company management (evidenced
                  by a certified Board resolution or an Officers' Certificate
                  delivered to the Trustee) the property acquired pursuant to
                  the consolidation, merger or asset transfer is adequate
                  security for the Lien; and

         (15)     Liens or encumbrances not otherwise permitted if, at the time
                  of incurrence and after giving effect thereto, the aggregate
                  of all such Permitted Encumbrances of the Company secured
                  thereby does not exceed 10% of Tangible Net Worth.

         "Tangible Net Worth" means (i) common stockholders' equity appearing on
the most recent balance sheet of the Company (or consolidated balance sheet of
the Company and its subsidiaries if the Company then has one or more
subsidiaries the accounts of which are consolidated with the accounts of the
Company) prepared in accordance with generally accepted accounting principles
less (ii) intangible assets (excluding intangible assets recoverable through
rates as prescribed by applicable regulatory authorities).

                                  ARTICLE FOUR
                                  MISCELLANEOUS

         SECTION 4.01      The recitals of fact herein and in the Notes due
[_______] (except the Trustee's Certificate) shall be taken as statements of the
Company and shall not be construed as made by the Trustee.

         SECTION 4.02      This Supplemental Indenture shall be construed in
connection with and as a part of the Indenture.

         SECTION 4.03

         (a)      If any provision of this Supplemental Indenture limits,
                  qualifies, or conflicts with another provision of the
                  Indenture required to be included in

                                       8

<PAGE>

                  indentures qualified under the Trust Indenture Act of 1939 (as
                  enacted prior to the date of this Supplemental Indenture) by
                  any of the provisions of Sections 310 to 317, inclusive, of
                  said Act, such required provisions shall control.

         (b)      In case any one or more of the provisions contained in this
                  Supplemental Indenture or in the Notes due [_______] issued
                  hereunder should be invalid, illegal, or unenforceable in any
                  respect, the validity, legality and enforceability of the
                  remaining provisions contained herein and therein shall not in
                  any way be affected, impaired, prejudiced or disturbed
                  thereby.

         SECTION 4.04      Whenever in this Supplemental Indenture either of the
parties hereto is named or referred to, this shall be deemed to include the
successors or assigns of such party, and all the covenants and agreements in
this Supplemental Indenture contained by or on behalf of the Company or by or on
behalf of the Trustee shall bind and inure to the benefit of the respective
successors and assigns of such parties, whether so expressed or not.

         SECTION 4.05

         (a)      This Supplemental Indenture may be simultaneously executed in
                  several counterparts, and all said counterparts executed and
                  delivered, each as an original, shall constitute but one and
                  the same instrument.

         (b)      The Table of Contents and the descriptive headings of the
                  several Articles of this Supplemental Indenture were
                  formulated, used and inserted in this Supplemental Indenture
                  for convenience only and shall not be deemed to affect the
                  meaning or construction of any of the provisions hereof.

                                       9

<PAGE>

         IN WITNESS WHEREOF, NORTHERN STATES POWER COMPANY has caused this
Supplemental Indenture to be signed by its President or a Vice President, and
attested by its Secretary or an Assistant Secretary and WELLS FARGO BANK
MINNESOTA, NATIONAL ASSOCIATION, has caused this Supplemental Indenture to be
signed by its President, Vice President, Assistant Vice President or authorized
Corporate Trust Officer, and attested by an authorized officer, this [_______]
day of [______________].

                                                 NORTHERN STATES POWER COMPANY

                                                 By:__________________________
                                                    Name:
                                                    Title:

ATTEST:

By:__________________________
   Name:
   Title:

                                                 WELLS FARGO BANK MINNESOTA,
                                                 NATIONAL ASSOCIATION,as Trustee

                                                 By:__________________________
                                                    Corporate Trust Officer

ATTEST:

By:__________________________
   Name:
   Title:

                                       10

<PAGE>

                                    EXHIBIT A

                                     FORM OF
                     [_______]% NOTES, SERIES DUE [_______]

REGISTERED                                                            REGISTERED

         THIS NOTE IS A GLOBAL SECURITY REGISTERED IN THE NAME OF THE DEPOSITORY
(REFERRED TO HEREIN) OR A NOMINEE THEREOF AND, UNLESS AND UNTIL IT IS EXCHANGED
IN WHOLE OR IN PART FOR THE INDIVIDUAL NOTES REPRESENTED HEREBY, THIS GLOBAL
SECURITY MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITORY TO A NOMINEE
OF THE DEPOSITORY OR BY A NOMINEE OF THE DEPOSITORY TO THE DEPOSITORY OR ANOTHER
NOMINEE OF THE DEPOSITORY OR BY THE DEPOSITORY OR ANY SUCH NOMINEE TO A
SUCCESSOR DEPOSITORY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITORY. UNLESS THIS
GLOBAL SECURITY IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY
TRUST COMPANY (55 WATER STREET, NEW YORK, NEW YORK), TO THE TRUSTEE FOR
REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS
REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS REQUESTED BY AN
AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY AND ANY PAYMENT IS
MADE TO CEDE & CO., 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.

                          NORTHERN STATES POWER COMPANY
             (INCORPORATED UNDER THE LAWS OF THE STATE OF MINNESOTA)

                     [_______]% NOTES, SERIES DUE [_______]

CUSIP: [_________________]                NUMBER:

ORIGINAL ISSUE DATE(S):                    PRINCIPAL
[____________________]                     AMOUNT(S):$[________]

INTEREST RATE: [_______]%                MATURITY DATE:
                                           [_______], [_______]

         NORTHERN STATES POWER COMPANY, a corporation of the State of Minnesota
(the "Company"), for value received hereby promises to pay to Cede & Co. or
registered assigns, the principal sum of [________] DOLLARS on the Maturity Date
set forth above, and to pay interest thereon from the Original Issue Date (or if
this Global Security has two or more Original Issue Dates, interest shall,
beginning on each such Original Issue Date, begin to accrue for that part of the
principal amount to which that Original Issue Date is applicable) set forth
above or from the most recent Interest Payment Date to

<PAGE>

which interest has been paid or duly provided for, quarterly in arrears on
[_______], [_______], [_______] and [_______] in each year, commencing on
[_______], at the per annum Interest Rate set forth above, until the principal
hereof is paid or made available for payment. No interest shall accrue on the
Maturity Date, so long as the principal amount of this Global Security is paid
on the Maturity Date. The interest so payable and punctually paid or duly
provided for on any such Interest Payment Date will, as provided in the
Indenture, be paid to the Person in whose name this Note is registered at the
close of business on the Regular Record Date for such interest, which shall be
[_______] or [_______], as the case may be, next preceding such Interest Payment
Date; provided, that the first Interest Payment Date for any part of this Note,
the Original Issue Date of which is after a Regular Record Date but prior to the
applicable Interest Payment Date, shall be the Interest Payment Date following
the next succeeding Regular Record Date; and provided, that interest payable on
the Maturity Date set forth above or, if applicable, upon redemption or
acceleration, shall be payable to the Person to whom principal shall be payable.
Except as otherwise provided in the Indenture (as defined below), any such
interest not so punctually paid or duly provided for will forthwith cease to be
payable to the Holder on such Regular Record Date and shall be paid to the
Person in whose name this Note is registered at the close of business on a
Special Record Date for the payment of such defaulted interest to be fixed by
the Trustee, notice whereof shall be given to Securityholders not more than
fifteen days or fewer than ten days prior to such Special Record Date. On or
before Noon, New York City time, or such other time as shall be agreed upon
between the Trustee and the Depository, of the day on which such payment of
interest is due on this Global Security (other than maturity), the Trustee shall
pay to the Depository such interest in same day funds. On or before Noon, New
York City time, or such other time as shall be agreed upon between the Trustee
and the Depository, of the day on which principal, and interest payable at
maturity, is due on this Global Security and following receipt of the necessary
funds from the Company, the Trustee shall deposit with the Depository the amount
equal to the principal, and interest payable at maturity, by wire transfer into
the account specified by the Depository. As a condition to the payment, on the
Maturity Date or upon redemption or acceleration, of any part of the principal
of this Global Security, the Depository shall surrender, or cause to be
surrendered, this Global Security to the Trustee, whereupon a new Global
Security shall be issued to the Depository.

         This Global Security is a global security in respect of a duly
authorized issue of Notes, Series due [_______] (the "Notes of this Series",
which term includes any Global Securities representing such Notes) of the
Company issued and to be issued under an Indenture dated as of July 1, 1999
between the Company, as successor obligor, and Wells Fargo Bank Minnesota,
National Association, as successor trustee (herein called the "Trustee", which
term includes any successor Trustee under the Indenture) and indentures
supplemental thereto (collectively, the "Indenture"). Under the Indenture, one
or more series of Securities may be issued and, as used herein, the term
"Securities" refers to the Notes of this Series and any other outstanding series
of Securities. Reference is hereby made for a more complete statement of the
respective rights, limitations of rights, duties and immunities under the
Indenture of the Company, the Trustee and the

                                       2

<PAGE>

Securityholders and of the terms upon which the Securities are and are to be
authenticated and delivered. This Global Security has been issued in respect of
the series designated on the first page hereof, which series is limited in
aggregate principal amount to $[_______].

         Each Note of this Series shall be dated and issued as of the date of
its authentication by the Trustee and shall bear an Original Issue Date or
Dates. Each Security or Global Security issued upon transfer, exchange or
substitution of such Security or Global Security shall bear the Original Issue
Date or Dates of such transferred, exchanged or substituted Security or Global
Security, as the case may be.

         [The Company may redeem the Notes of this Series at any time, in whole
or in part, at a redemption price equal to the greater of (i) the principal
amount of such Notes of this Series to be redeemed or (ii) the sum of the
present values of the remaining scheduled payments of principal and interest
thereon, discounted to the date of redemption on a semi-annual basis (assuming a
360-day year consisting of twelve 30-day months) at the Treasury Yield (as
defined below) plus [_______] basis points, plus in each case accrued interest
thereon to the date of redemption.

                  "Treasury Yield" means, with respect to any redemption date,
         the rate per annum equal to the semiannual equivalent yield to maturity
         of the Comparable Treasury Issue, assuming a price for the Comparable
         Treasury Issue (expressed as a percentage of its principal amount)
         equal to the Comparable Treasury Price for the redemption date.

                  "Comparable Treasury Issue" means the United States Treasury
         security selected by an Independent Investment Banker as having a
         maturity comparable to the remaining term of the Notes of this Series
         that would be utilized, at the time of selection and in accordance with
         customary financial practice, in pricing new issues of corporate debt
         securities of comparable maturity to the remaining term of the Notes.

                  "Independent Investment Banker" means [____________________]
         or its successor or, if such firm is unwilling or unable to select the
         Comparable Treasury Issue, one of the remaining Reference Treasury
         Dealers appointed by the Trustee after consultation with the Company.

                  "Comparable Treasury Price" means, with respect to any
         redemption date, (i) the average of the bid and asked prices for the
         Comparable Treasury Issue (expressed in each case as a percentage of
         its principal amount) on the third business day preceding such
         redemption date, as set forth in the daily statistical release (or any
         successor release) published by the Federal Reserve Bank of New York
         and designated "Composite 3:30 p.m. Quotations for U.S. Government
         Securities" or (ii) if that release (or any successor release) is not
         published or does not contain such prices on such business day, (A) the
         average of the Reference Treasury Dealer Quotations for such redemption
         date, after excluding the highest and lowest such Reference Treasury
         Dealer Quotations for such redemption date,

                                       3

<PAGE>

         or (B) if fewer than four such Reference Treasury Dealer Quotations are
         obtained, then the average of all such Quotations.

                  "Reference Treasury Dealer Quotations" means, with respect to
         each Reference Treasury Dealer and any redemption date, the average, as
         determined by the Trustee, of the bid and asked prices for the
         Comparable Treasury Issue (expressed in each case as a percentage of
         its principal amount) quoted in writing to the Trustee by such
         Reference Treasury Dealer at 5:00 p.m. on the third business day
         preceding such redemption date.

                  "Reference Treasury Dealer" means (i) each of
         [__________________] and any other primary U.S. Government Securities
         dealer in New York City (a "Primary Treasury Dealer") designated by,
         and not affiliated with, [_____________________], provided, however,
         that if [_____________________] or any of its designees shall cease to
         be a Primary Treasury Dealer, the Company shall substitute another
         Primary Treasury Dealer as a substitute for such entity and (ii) any
         other Primary Treasury Dealer selected by the Company.]

         [On or after [_______], the Company may redeem the Notes of this Series
at any time, in whole or in part, at a redemption price equal to the principal
amount of such Notes of this Series to be redeemed, plus accrued interest to the
date of redemption.

         Notice of redemption will be given by mail to Holders of Notes of this
Series not less than 30 or more than 60 days prior to the date fixed for
redemption, all as provided in the Indenture. In the event of redemption of this
Global Security in part only, a new Global Security or Securities of like tenor
and series for the unredeemed portion hereof will be issued in the name of the
Securityholder hereof upon the surrender hereof.

         Interest payments for this Global Security shall be computed and paid
on the basis of a 360-day year of twelve 30-day months. In any case where any
Interest Payment Date or date on which the principal of this Global Security is
required to be paid is not a Business Day, then payment of principal or interest
need not be made on such date but may be made on the next succeeding Business
Day with the same force and effect as if made on such Interest Payment Date or
date on which the principal of this Global Security is required to be paid and,
in the case of timely payment thereof, no interest shall accrue for the period
from and after such Interest Payment Date or the date on which the principal of
this Global Security is required to be paid.

         The Company, at its option, and subject to the terms and conditions
provided in the Indenture, will be discharged from any and all obligations in
respect of the Securities (except for certain obligations including obligations
to register the transfer or exchange of Securities, replace stolen, lost or
mutilated Securities, maintain paying agencies and hold monies for payment in
trust, all as set forth in the Indenture) if the Company deposits with the
Trustee money, U.S. Government Obligations which through the payment of interest
thereon and principal thereof in accordance with their terms will provide money,

                                       4

<PAGE>

or a combination of money and U.S. Government Obligations, in any event in an
amount sufficient, without reinvestment, to pay all the principal of and any
premium and interest on the Securities on the dates such payments are due in
accordance with the terms of the Securities.

         If an Event of Default shall occur and be continuing, the principal of
the Securities may be declared due and payable in the manner and with the effect
provided in the Indenture.

         The Indenture permits, with certain exceptions as therein provided, the
amendment thereof and the modifications of the rights and obligations of the
Company and the rights of the Securityholders under the Indenture at any time by
the Company and the Trustee with the consent of the Holders of not less than a
majority in principal amount of the outstanding Securities. Any such consent or
waiver by the Holder of this Global Security shall be conclusive and binding
upon such Holder and upon all future Holders of this Global Security and of any
Note issued upon the registration of transfer hereof or in exchange therefor or
in lieu thereof whether or not notation of such consent or waiver is made upon
the Note.

         As set forth in and subject to the provisions of the Indenture, no
Holder of any Securities will have any right to institute any proceeding with
respect to the Indenture or for any remedy thereunder unless such Holder shall
have previously given to the Trustee written notice of a continuing Event of
Default with respect to such Securities, the Holders of not less than a majority
in principal amount of the outstanding Securities affected by such Event of
Default shall have made written request and offered reasonable indemnity to the
Trustee to institute such proceeding as Trustee and the Trustee shall have
failed to institute such proceeding within 60 days; provided, however, that such
limitations do not apply to a suit instituted by the Holder hereof for the
enforcement of payment of the principal of and interest on this Note on or after
the respective due dates expressed here.

         No reference herein to the Indenture and to provisions of this Global
Security or of the Indenture shall alter or impair the obligation of the
Company, which is absolute and unconditional, to pay the principal of and
interest on this Global Security at the times, places and rates and in the coin
or currency prescribed in the Indenture.

         As provided in the Indenture and subject to certain limitations therein
set forth, this Global Security may be transferred only as permitted by the
legend hereto.

         If at any time the Depository for this Global Security notifies the
Company that it is unwilling or unable to continue as Depository for this Global
Security or if at any time the Depository for this Global Security shall no
longer be eligible or in good standing under the Securities Exchange Act of
1934, as amended, or other applicable statute or regulation, the Company shall
appoint a successor Depository with respect to this Global Security. If a
successor Depository for this Global Security is not appointed by the Company
within 90 days after the Company receives such notice or becomes aware of

                                       5

<PAGE>

such ineligibility, the Company's election to issue this Note in global form
shall no longer be effective with respect to this Global Security and the
Company will execute, and the Trustee, upon receipt of a Company Order for the
authentication and delivery of individual Notes of this Series in exchange for
this Global Security, will authenticate and deliver individual Notes of this
Series of like tenor and terms in definitive form in an aggregate principal
amount equal to the principal amount of this Global Security.

         The Company may at any time and in its sole discretion determine that
all Notes of this Series (but not less than all) issued or issuable in the form
of one or more Global Securities shall no longer be represented by such Global
Security or Securities. In such event, the Company shall execute, and the
Trustee, upon receipt of a Company Order for the authentication and delivery of
individual Notes of this Series in exchange for such Global Security, shall
authenticate and deliver, individual Notes of this Series of like tenor and
terms in definitive form in an aggregate principal amount equal to the principal
amount of such Global Security or Securities in exchange for such Global
Security or Securities.

         Under certain circumstances specified in the Indenture, the Depository
may be required to surrender any two or more Global Securities which have
identical terms (but which may have differing Original Issue Dates) to the
Trustee, and the Company shall execute and the Trustee shall authenticate and
deliver to, or at the direction of, the Depository a Global Security in
principal amount equal to the aggregate principal amount of, and with all terms
identical to, the Global Securities surrendered thereto and that shall indicate
all Original Issue Dates and the principal amount applicable to each such
Original Issue Date.

         The Indenture and the Securities shall be governed by, and construed in
accordance with, the laws of the State of Minnesota.

         Unless the certificate of authentication hereon has been executed by
the Trustee, directly or through an Authenticating Agent by manual signature of
an authorized officer, this Global Security shall not be entitled to any benefit
under the Indenture or be valid or obligatory for any purpose.

         All terms used in this Global Security which are defined in the
Indenture shall have the meanings assigned to them in the Indenture unless
otherwise indicated herein.

                                       6

<PAGE>

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

                                          NORTHERN STATES POWER COMPANY

                                          By:___________________________________

Dated:                                    Title: _______________________________

                                          Attest:_______________________________

                                          Title:________________________________

           TRUSTEE'S CERTIFICATE
             OF AUTHENTICATION

This Note is one of the Securities of the
series herein designated, described or
provided for in the within-mentioned
Indenture.

WELLS FARGO BANK MINNESOTA, NATIONAL
ASSOCIATION, as Trustee

By:______________________________________
             Authorized Officer

                                       7

<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               UNIF GIFT
                                              MIN ACT -- _____ Custodian _______
                                                        (Cust)           (Minor)

TEN ENT -- as tenants by the entireties      Under Uniform Gifts to Minors

JT TEN -- as joint tenants with right of     __________________________________
survivorship and not as tenants in common
                                              State

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

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

PLEASE INSERT SOCIAL SECURITY OR OTHER
IDENTIFYING NUMBER OF ASSIGNEE
_______________________________________________________________________
                   Please print or typewrite name and address
                      including postal zip code of assignee
___________________________________________
the within security and all rights
thereunder, hereby irrevocably constituting
and appointing ____________ attorney to
transfer said security on the books of the
Company, with full power of substitution
in the premises.

Dated:___________________

                                              __________________________________
                                                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.

                                       8