Document:

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                                 Exhibit 4.54

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                    PREFERRED SECURITIES GUARANTEE AGREEMENT

                                 NSP Financing I

                           Dated as of August 18, 2000

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                                TABLE OF CONTENTS

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ARTICLE I           DEFINITIONS AND INTERPRETATION................................................................1
   SECTION 1.1.          Definitions and Interpretation...........................................................1
ARTICLE II          TRUST INDENTURE ACT...........................................................................4
   SECTION 2.1.          Trust Indenture Act; Application.........................................................4
   SECTION 2.2.          Lists of Holders of Securities...........................................................5
   SECTION 2.3.          Reports by the Preferred Guarantee Trustee...............................................5
   SECTION 2.4.          Periodic Reports to Preferred Guarantee Trustee..........................................5
   SECTION 2.5.          Evidence of Compliance with Conditions Precedent.........................................5
   SECTION 2.6.          Events of Default; Waiver................................................................5
   SECTION 2.7.          Event of Default; Notice.................................................................6
   SECTION 2.8.          Conflicting Interests....................................................................6
ARTICLE III.        POWERS, DUTIES AND RIGHTS OF PREFERRED
                    GUARANTEE TRUSTEE.............................................................................6
   SECTION 3.1.          Powers and Duties of the Preferred Guarantee Trustee.....................................6
   SECTION 3.2.          Certain Rights of Preferred Guarantee Trustee............................................8
   SECTION 3.3.          Not Responsible for Recitals or Issuance of Guarantee...................................10
ARTICLE IV.         PREFERRED GUARANTEE TRUSTEE..................................................................10
   SECTION 4.1.          Preferred Guarantee Trustee; Eligibility................................................10
   SECTION 4.2.          Appointment, Removal and Resignation of Preferred Guarantee Trustees....................11
ARTICLE V.          GUARANTEE....................................................................................12
   SECTION 5.1.          Guarantee...............................................................................12
   SECTION 5.2.          Waiver of Notice and Demand.............................................................12
   SECTION 5.3.          Obligations Not Affected................................................................12
   SECTION 5.4.          Rights of Holders.......................................................................13
   SECTION 5.5.          Guarantee of Payment....................................................................13
   SECTION 5.6.          Subrogation.............................................................................13
   SECTION 5.7.          Independent Obligations.................................................................14
ARTICLE VI.         LIMITATION OF TRANSACTIONS; SUBORDINATION....................................................14
   SECTION 6.1.          Limitation of Transactions..............................................................14
   SECTION 6.2.          Ranking.................................................................................14
ARTICLE VII.        TERMINATION..................................................................................15
   SECTION 7.1.          Termination.............................................................................15
ARTICLE VIII.       INDEMNIFICATION..............................................................................15
   SECTION 8.1.          Exculpation.............................................................................15
   SECTION 8.2.          Indemnification.........................................................................15
ARTICLE IX.         MISCELLANEOUS................................................................................16
   SECTION 9.1.          Successors and Assigns..................................................................16
   SECTION 9.2.          Amendments..............................................................................16

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   SECTION 9.3.          Notices.................................................................................16
   SECTION 9.4.          Benefit.................................................................................17
   SECTION 9.5.          Governing Law...........................................................................17
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                    PREFERRED SECURITIES GUARANTEE AGREEMENT

         This GUARANTEE AGREEMENT (the "Preferred Securities Guarantee"), dated
as of August 18, 2000, is executed and delivered by Northern States Power
Company, a Minnesota corporation (formerly "Northern Power Corporation", the
"Guarantor"), and Wilmington Trust Company, as trustee (the "Preferred Guarantee
Trustee"), for the benefit of the Holders (as defined herein) from time to time
of the Preferred Securities (as defined herein) of NSP Financing I, a Delaware
statutory business trust (the "Issuer").

         WHEREAS, pursuant to an Amended and Restated Declaration of Trust (the
"Declaration"), dated as of January 31, 1997, among the trustees of the Issuer
named therein, the Xcel Energy Inc., a Minnesota corporation (formerly "Northern
Power Company", hereinafter "Xcel") as sponsor, and the holders from time to
time of undivided beneficial interests in the assets of the Issuer, the Issuer
issued on the date thereof 8,000,000 preferred securities, having an aggregate
liquidation amount of $200,000,000, designated the 7-7/8% Trust Originated
Preferred Securities (the "Preferred Securities");

         WHEREAS, as incentive for the Holders to purchase the Preferred
Securities, Xcel irrevocably and unconditionally agreed, to the extent set forth
in that certain Preferred Securities Guarantee Agreement dated as of January 31,
1997 by Xcel and the Preferred Guarantee Trustee (the "Xcel Preferred Securities
Guarantee"), to pay to the Holders of the Preferred Securities the Guarantee
Payments (as defined therein) and to make certain other payments on the terms
and conditions set forth therein;

         WHEREAS, Xcel also executed and delivered a guarantee agreement (the
"Xcel Common Securities Guarantee") in substantially identical terms to the Xcel
Preferred Securities Guarantee for the benefit of the holders of the Common
Securities (as defined herein), except that if an Event of Default (as defined
in the Indenture), has occurred and is continuing, the rights of holders of the
Common Securities to receive Guarantee Payments under the Xcel Common Securities
Guarantee are subordinated to the rights of Holders of Preferred Securities to
receive Guarantee Payments under the Xcel Preferred Securities Guarantee;

         WHEREAS, pursuant to the Indenture as supplemented by the First
Supplemental Indenture dated as of January 31, 1997, and the Second Supplemental
Indenture dated as of August 18, 2000, Guarantor has assumed the obligations of
Xcel under the Indenture and the Securities (as defined in the Indenture) as a
joint and several co-obligor with Xcel under the Indenture as supplemented;

         WHEREAS, Guarantor desires irrevocably and unconditionally to agree, to
the extent set forth in this Preferred Securities Guarantee, to pay to the
Holders of the Preferred Securities the Guarantee Payments (as defined herein)
and to make certain other payments on the terms and conditions set forth herein;
and

         WHEREAS, Guarantor is also executing and delivering a guarantee
agreement (the "Common Securities Guarantee") in substantially identical terms
to this Preferred Securities

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Guarantee for the benefit of the holders of the Common Securities (as defined
herein), except that if an Event of Default, has occurred and is continuing,
the rights of holders of the Common Securities to receive Guarantee Payments
under the Common Securities Guarantee are subordinated to the rights of
Holders of Preferred Securities to receive Guarantee Payments under this
Preferred Securities Guarantee;

         NOW, THEREFORE, in consideration of the purchase by each Holder of
Preferred Securities, which purchase the Guarantor hereby agrees shall benefit
the Guarantor, the Guarantor executes and delivers this Preferred Securities
Guarantee for the benefit of the Holders.

                                   ARTICLE I.
                         DEFINITIONS AND INTERPRETATION

SECTION 1.1.               Definitions and Interpretation

         In this Preferred Securities Guarantee, unless the context otherwise
requires:

         (a) Capitalized terms used in this Preferred Securities Guarantee but
not defined in the preamble above have the respective meanings assigned to them
in this Section 1.1;

         (b) a term defined anywhere in this Preferred Securities Guarantee has
the same meaning throughout;

         (c) all references to "the Preferred Securities Guarantee" or "this
Preferred Securities Guarantee" are to this Preferred Securities Guarantee as
modified, supplemented or amended from time to time;

         (d) all references in this Preferred Securities Guarantee to Articles
and Sections are to Articles and Sections of this Preferred Securities
Guarantee, unless otherwise specified;

         (e) a term defined in the Trust Indenture Act has the same meaning when
used in this Preferred Securities Guarantee, unless otherwise defined in this
Preferred Securities Guarantee or unless the context otherwise requires; and

         (f) a reference to the singular includes the plural and vice versa.

         "Affiliate" has the same meaning as given to that term in Rule 405 of
the Securities Act of 1933, as amended, or any successor rule thereunder.

         "Authorized Officer" of a Person means any Person that is authorized to
bind such Person.

         "Business Day" means any day other than a day on which banking
institutions in the City of New York, New York are authorized or required by any
applicable law to close.

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         "Common Securities" means the securities representing common undivided
beneficial interests in the assets of the Issuer.

         "Corporate Trust Office" means the office of the Preferred Guarantee
Trustee at which the corporate trust business of the Preferred Guarantee Trustee
shall, at any particular time, be principally administered, which office at the
date of execution of this Agreement is located at Wilmington Trust Company,
Rodney Square North, 1100 North Market Street, Wilmington, Delaware 19890,
Attention: Corporate Trust Administration.

         "Covered Person" means any Holder or beneficial owner of Preferred
Securities.

         "Debentures" means the series of junior subordinated debt securities of
the Guarantor designated the 7-7/8% Junior Subordinated Debentures due 2037 held
by the Institutional Trustee (as defined in the Declaration) of the Issuer.

         "Event of Default" means a default by the Guarantor on any of its
payment or other obligations under this Preferred Securities Guarantee.

         "Guarantee Payments" means the following payments or distributions,
without duplication, with respect to the Preferred Securities, to the extent not
paid or made by the Issuer: (i) any accrued and unpaid Distributions (as defined
in the Declaration) that are required to be paid on such Preferred Securities to
the extent the Issuer shall have funds available therefor, (ii) the redemption
price, including all accrued and unpaid Distributions to the date of redemption
(the "Redemption Price") to the extent the Issuer has funds available therefor,
with respect to any Preferred Securities called for redemption by the Issuer,
and (iii) upon a voluntary or involuntary dissolution, winding-up or termination
of the Issuer (other than in connection with the distribution of Debentures to
the Holders in exchange for Preferred Securities as provided in the
Declaration), the lesser of (a) the aggregate of the liquidation amount and all
accrued and unpaid Distributions on the Preferred Securities to the date of
payment, to the extent the Issuer shall have funds available therefor, and (b)
the amount of assets of the Issuer remaining available for distribution to
Holders in liquidation of the Issuer (in either case, the "Liquidation
Distribution"). If an event of default under the Indenture has occurred and is
continuing, the rights of holders of the Common Securities to receive payments
under the Common Securities Guarantee Agreement are subordinated to the rights
of Holders of Preferred Securities to receive Guarantee Payments.

         "Holder" shall mean any holder, as registered on the books and records
of the Issuer of any Preferred Securities; provided, however, that, in
determining whether the holders of the requisite percentage of Preferred
Securities have given any request, notice, consent or waiver hereunder, "Holder"
shall not include the Guarantor or any Affiliate of the Guarantor.

         "Indemnified Person" means the Preferred Guarantee Trustee, any
Affiliate of the Preferred Guarantee Trustee, or any officers, directors,
shareholders, members, partners, employees, representatives, nominees,
custodians or agents of the Preferred Guarantee Trustee.

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         "Indenture" means the Indenture dated as of January 30, 1997, among the
Guarantor (the "Debenture Issuer") and Wells Fargo Bank Minnesota, National
Association (formerly, Norwest Bank Minnesota, National Association), as
trustee, and any indenture supplemental thereto pursuant to which certain
subordinated debt securities of the Debenture Issuer are to be issued to the
Institutional Trustee of the Issuer.

         "Majority in liquidation amount of the Securities" means, except as
provided by the Trust Indenture Act, a vote by Holder(s) of Preferred
Securities, voting separately as a class, of more than 50% of the liquidation
amount (including the stated amount that would be paid on redemption,
liquidation or otherwise, plus accrued and unpaid Distributions to the date upon
which the voting percentages are determined) of all Preferred Securities.

         "Officers' Certificate" means, with respect to any Person, a
certificate signed by two Authorized Officers of such Person. Any Officers'
Certificate delivered with respect to compliance with a condition or covenant
provided for in this Preferred Securities Guarantee shall include:

         (a) a statement that each officer signing the Officers' Certificate has
read the covenant or condition and the definition relating thereto;
         (b) a brief statement of the nature and scope of the examination or
investigation undertaken by each officer in rendering the Officers' Certificate;

         (c) a statement that each such officer has made such examination or
investigation as, in such officer's opinion, is necessary to enable such officer
to express an informed opinion as to whether or not such covenant or condition
has been complied with; and

         (d) a statement as to whether, in the opinion of each such officer,
such condition or covenant has been complied with.

         "Person" means a legal person, including any individual, corporation,
estate, partnership, joint venture, association, joint stock company, limited
liability company, trust, unincorporated association, or government or any
agency or political subdivision thereof, or any other entity of whatever nature.

         "Preferred Guarantee Trustee" means Wilmington Trust Company until a
Successor Preferred Guarantee Trustee has been appointed and has accepted such
appointment pursuant to the terms of this Preferred Securities Guarantee and
thereafter means each such Successor Preferred Guarantee Trustee.

         "Responsible Officer" means, with respect to the Preferred Guarantee
Trustee, any officer within the Corporate Trust Office of the Preferred
Guarantee Trustee, including any vice-president, any assistant vice-president,
any assistant secretary, the treasurer, any assistant treasurer or other officer
of the Corporate Trust Office of the Preferred Guarantee Trustee customarily
performing functions similar to those performed by any of the above designated
officers and also means, with respect to a particular corporate trust matter,
any other officer to

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whom such matter is referred because of that officer's knowledge of and
familiarity with the particular subject.

         "Successor Preferred Guarantee Trustee" means a successor Preferred
Guarantee Trustee possessing the qualifications to act as Preferred Guarantee
Trustee under Section 4.1.

         "Trust Indenture Act" means the Trust Indenture Act of 1939, as
amended.

                                   ARTICLE II.
                               TRUST INDENTURE ACT

SECTION 2.1.     Trust Indenture Act; Application

         (a) This Preferred Securities Guarantee is subject to the provisions of
the Trust Indenture Act that are required to be part of this Preferred
Securities Guarantee and shall, to the extent applicable, be governed by such
provisions; and

         (b) if and to the extent that any provision of this Preferred
Securities Guarantee limits, qualifies or conflicts with the duties imposed by
Section 310 to 317, inclusive, of the Trust Indenture Act, such imposed duties
shall control.

SECTION 2.2.     Lists of Holders of Securities

         (a) Either the Guarantor or Xcel shall provide the Preferred Guarantee
Trustee with a list, in such form as the Preferred Guarantee Trustee may
reasonably require, of the names and addresses of the Holders of the Preferred
Securities ("List of Holders") as of such date, (i) within 1 Business Day after
January 1 and June 30 of each year, and (ii) at any other time within 30 days of
receipt by the Guarantor of a written request for a List of Holders as of a date
no more than 14 days before such List of Holders is given to the Preferred
Guarantee Trustee, provided that neither the Guarantor nor Xcel shall be
obligated to provide such List of Holders at any time the List of Holders does
not differ from the most recent List of Holders given to the Preferred Guarantee
Trustee by the Guarantor or Xcel. The Preferred Guarantee Trustee may destroy
any List of Holders previously given to it on receipt of a new List of Holders.

         (b) The Preferred Guarantee Trustee shall comply with its obligations
under Section 311(a), 311(b) and Section 312(b) of the Trust Indenture Act.

SECTION 2.3.     Reports by the Preferred Guarantee Trustee

         Within 60 days after May 15 of each year, the Preferred Guarantee
Trustee shall provide to the Holders of the Preferred Securities such reports as
are required by Section 313 of the Trust Indenture Act, if any, in the form and
in the manner provided by Section 313 of the Trust Indenture Act. The Preferred
Guarantee Trustee shall also comply with the requirements of Section 313(d) of
the Trust Indenture Act.

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SECTION 2.4.     Periodic Reports to Preferred Guarantee Trustee

         The Guarantor shall provide to the Preferred Guarantee Trustee such
documents, reports and information as required by Section 314 of the Trust
Indenture Act (if any) and the compliance certificate required by Section 314 of
the Trust Indenture Act in the form, in the manner and at the times required by
Section 314 of the Trust Indenture Act.

SECTION 2.5.     Evidence of Compliance with Conditions Precedent

         The Guarantor shall provide to the Preferred Guarantee Trustee such
evidence of compliance with any conditions precedent, if any, provided for in
this Preferred Securities Guarantee that relate to any of the matters set forth
in Section 314(c) of the Trust Indenture Act. Any certificate or opinion
required to be given by an officer pursuant to Section 314(c)(1) may be given in
the form of an Officers' Certificate.

SECTION 2.6.     Events of Default; Waiver

         The Holders of a Majority in liquidation amount of Preferred Securities
may, by vote, on behalf of the Holders of all of the Preferred Securities, waive
any past Event of Default and its consequences. Upon such waiver, any such Event
of Default shall cease to exist, and any Event of Default arising therefrom
shall be deemed to have been cured, for every purpose of this Preferred
Securities Guarantee, but no such waiver shall extend to any subsequent or other
default or Event of Default or impair any right consequent thereon.

SECTION 2.7.     Event of Default; Notice

         (a) The Preferred Guarantee Trustee shall, within 90 days after the
occurrence of an Event of Default, transmit by mail, first class postage
prepaid, to the Holders of the Preferred Securities, notices of all Events of
Default actually known to a Responsible Officer of the Preferred Guarantee
Trustee, unless such defaults have been cured before the giving of such notice,
provided, that, the Preferred Guarantee Trustee shall be protected in
withholding such notice if and so long as a Responsible Officer of the Preferred
Guarantee Trustee in good faith determines that the withholding of such notice
is in the interests of the Holders of the Preferred Securities.

         (b) The Preferred Guarantee Trustee shall not be deemed to have
knowledge of any Event of Default unless the Preferred Guarantee Trustee shall
have received written notice, or unless a Responsible Officer of the Preferred
Guarantee Trustee charged with the administration of the Declaration shall have
obtained actual knowledge thereof.

SECTION 2.8.     Conflicting Interests

         The Declaration shall be deemed to be specifically described in this
Preferred Securities Guarantee for the purposes of clause (i) of the first
proviso contained in Section 310(b) of the Trust Indenture Act.

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                                  ARTICLE III.
                          POWERS, DUTIES AND RIGHTS OF
                           PREFERRED GUARANTEE TRUSTEE

SECTION 3.1.     Powers and Duties of the Preferred Guarantee Trustee

         (a) This Preferred Securities Guarantee shall be held by the Preferred
Guarantee Trustee for the benefit of the Holders of the Preferred Securities,
and the Preferred Guarantee Trustee shall not transfer this Preferred Securities
Guarantee to any Person except a Holder of Preferred Securities exercising his
or her rights pursuant to Section 5.4(b) or to a Successor Preferred Guarantee
Trustee on acceptance by such Successor Preferred Guarantee Trustee of its
appointment to act as Successor Preferred Guarantee Trustee. The right, title
and interest of the Preferred Guarantee Trustee shall automatically vest in any
Successor Preferred Guarantee Trustee, and such vesting and cessation of title
shall be effective whether or not conveyancing documents have been executed and
delivered pursuant to the appointment of such Successor Preferred Guarantee
Trustee.

         (b) If an Event of Default actually known to a Responsible Officer of
the Preferred Guarantee Trustee has occurred and is continuing, the Preferred
Guarantee Trustee shall enforce this Preferred Securities Guarantee for the
benefit of the Holders of the Preferred Securities.

         (c) The Preferred Guarantee Trustee, before the occurrence of any Event
of Default and after the curing of all Events of Default that may have occurred,
shall undertake to perform only such duties as are specifically set forth in
this Preferred Securities Guarantee, and no implied covenants shall be read into
this Preferred Securities Guarantee against the Preferred Guarantee Trustee. In
case an Event of Default has occurred (that has not been cured or waived
pursuant to Section 2.6) and is actually known to a Responsible Officer of the
Preferred Guarantee Trustee, the Preferred Guarantee Trustee shall exercise such
of the rights and powers vested in it by this Preferred Securities Guarantee,
and use the same degree of care and skill in its exercise thereof, as a prudent
person would exercise or use under the circumstances in the conduct of his or
her own affairs.

         (d) No provision of this Preferred Securities Guarantee shall be
construed to relieve the Preferred Guarantee Trustee from liability for its own
negligent action, its own negligent failure to act, or its own willful
misconduct, except that:

                  (i) prior to the occurrence of any Event of Default and after
         the curing or waiving of all such Events of Default that may have
         occurred:

                           (A) the duties and obligations of the Preferred
                  Guarantee Trustee shall be determined solely by the express
                  provisions of this Preferred Securities Guarantee, and the
                  Preferred Guarantee Trustee shall not be liable except for the
                  performance of such duties and obligations as are specifically
                  set forth in this

                                      -7-

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                  Preferred Securities Guarantee, and no implied covenants or
                  obligations shall be read into this Preferred Securities
                  Guarantee against the Preferred Guarantee Trustee; and

                           (B) in the absence of bad faith on the part of the
                  Preferred Guarantee Trustee, the Preferred Guarantee Trustee
                  may conclusively rely, as to the truth of the statements and
                  the correctness of the opinions expressed therein, upon any
                  certificates or opinions furnished to the Preferred Guarantee
                  Trustee and conforming to the requirements of this Preferred
                  Securities Guarantee; but in the case of any such certificates
                  or opinions that by any provision hereof are specifically
                  required to be furnished to the Preferred Guarantee Trustee,
                  the Preferred Guarantee Trustee shall be under a duty to
                  examine the same to determine whether or not they conform to
                  the requirements of this Preferred Securities Guarantee;

                  (ii) the Preferred Guarantee Trustee shall not be liable for
         any error of judgment made in good faith by a Responsible Officer of
         the Preferred Guarantee Trustee, unless it shall be proved that the
         Preferred Guarantee Trustee was negligent in ascertaining the pertinent
         facts upon which such judgment was made;

                  (iii) the Preferred Guarantee Trustee shall not be liable with
         respect to any action taken or omitted to be taken by it in good faith
         in accordance with the direction of the Holders of not less than a
         Majority in liquidation amount of the Preferred Securities relating to
         the time, method and place of conducting any proceeding for any remedy
         available to the Preferred Guarantee Trustee, or exercising any trust
         or power conferred upon the Preferred Guarantee Trustee under this
         Preferred Securities Guarantee; and

                  (iv) no provision of this Preferred Securities Guarantee shall
         require the Preferred Guarantee Trustee to expend or risk its own funds
         or otherwise incur personal financial liability in the performance of
         any of its duties or in the exercise of any of its rights or powers, if
         the Preferred Guarantee Trustee shall have reasonable grounds for
         believing that the repayment of such funds or liability is not
         reasonably assured to it under the terms of this Preferred Securities
         Guarantee or indemnity, reasonably satisfactory to the Preferred
         Guarantee Trustee, against such risk or liability is not reasonably
         assured to it.

SECTION 3.2.     Certain Rights of Preferred Guarantee Trustee

         (a)      Subject to the provisions of Section 3.1:

                  (i) The Preferred Guarantee Trustee may conclusively rely, and
         shall be fully protected in acting or refraining from acting upon, any
         resolution, certificate, statement, instrument, opinion, report,
         notice, request, direction, consent, order, bond, debenture, note,
         other evidence of indebtedness or other paper or document believed by
         it to be genuine and to have been signed, sent or presented by the
         proper party or parties.

                                      -8-

<PAGE>

                  (ii) Any direction or act of the Guarantor contemplated by
         this Preferred Securities Guarantee shall be sufficiently evidenced by
         a Direction (as defined in the Declaration) or an Officers'
         Certificate.

                  (iii) Whenever, in the administration of this Preferred
         Securities Guarantee, the Preferred Guarantee Trustee shall deem it
         desirable that a matter be proved or established before taking,
         suffering or omitting any action hereunder, the Preferred Guarantee
         Trustee (unless other evidence is herein specifically prescribed) may,
         in the absence of bad faith on its part, request and conclusively rely
         upon an Officers' Certificate which, upon receipt of such request,
         shall be promptly delivered by the Guarantor.

                  (iv) The Preferred Guarantee Trustee shall have no duty to see
         to any recording, filing or registration of any instrument (or any
         rerecording, refiling or registration thereof).

                  (v) The Preferred Guarantee Trustee may consult with counsel,
         and the written advice or opinion of such counsel with respect to legal
         matters shall be full and complete authorization and protection in
         respect of any action taken, suffered or omitted by it hereunder in
         good faith and in accordance with such advice or opinion. Such counsel
         may be counsel to the Guarantor or any of its Affiliates and may
         include any of its employees. The Preferred Guarantee Trustee shall
         have the right at any time to seek instructions concerning the
         administration of this Preferred Securities Guarantee from any court of
         competent jurisdiction.

                  (vi) The Preferred Guarantee Trustee shall be under no
         obligation to exercise any of the rights or powers vested in it by this
         Preferred Securities Guarantee at the request or direction of any
         Holder, unless such Holder shall have provided to the Preferred
         Guarantee Trustee such security and indemnity, reasonably satisfactory
         to the Preferred Guarantee Trustee, against the costs, expenses
         (including attorneys' fees and expenses and the expenses of the
         Preferred Guarantee Trustee's agents, nominees or custodians) and
         liabilities that might be incurred by it in complying with such request
         or direction, including such reasonable advances as may be requested by
         the Preferred Guarantee Trustee; provided that, nothing contained in
         this Section 3.2(a)(vi) shall be taken to relieve the Preferred
         Guarantee Trustee, upon the occurrence of an Event of Default, of its
         obligation to exercise the rights and powers vested in it by this
         Preferred Securities Guarantee.

                  (vii) The Preferred Guarantee Trustee shall not be bound to
         make any investigation into the facts or matters stated in any
         resolution, certificate, statement, instrument, opinion, report,
         notice, request, direction, consent, order, bond, debenture, note,
         other evidence of indebtedness or other paper or document, but the
         Preferred Guarantee Trustee, in its discretion, may make such further
         inquiry or investigation into such facts or matters as it may see fit.

                                      -9-

<PAGE>

                  (viii) The Preferred Guarantee Trustee may execute any of the
         trusts or powers hereunder or perform any duties hereunder either
         directly or by or through agents, nominees, custodians or attorneys,
         and the Preferred Guarantee Trustee shall not be responsible for any
         misconduct or negligence on the part of any agent or attorney appointed
         with due care by it hereunder.

                  (ix) Any action taken by the Preferred Guarantee Trustee or
         its agents hereunder shall bind the Holders of the Preferred
         Securities, and the signature of the Preferred Guarantee Trustee or its
         agents alone shall be sufficient and effective to perform any such
         action. No third party shall be required to inquire as to the authority
         of the Preferred Guarantee Trustee to so act or as to its compliance
         with any of the terms and provisions of this Preferred Securities
         Guarantee, both of which shall be conclusively evidenced by the
         Preferred Guarantee Trustee's or its agent's taking such action.

                  (x) Whenever in the administration of this Preferred
         Securities Guarantee the Preferred Guarantee Trustee shall deem it
         desirable to receive instructions with respect to enforcing any remedy
         or right or taking any other action hereunder, the Preferred Guarantee
         Trustee (i) may request instructions from the Holders of a Majority in
         liquidation amount of the Preferred Securities, (ii) may refrain from
         enforcing such remedy or right or taking such other action until such
         instructions are received, and (iii) shall be protected in conclusively
         relying on or acting in accordance with such instructions.

         (b) No provision of this Preferred Securities Guarantee shall be deemed
to impose any duty or obligation on the Preferred Guarantee Trustee to perform
any act or acts or exercise any right, power, duty or obligation conferred or
imposed on it in any jurisdiction in which it shall be illegal, or in which the
Preferred Guarantee Trustee shall be unqualified or incompetent in accordance
with applicable law, to perform any such act or acts or to exercise any such
right, power, duty or obligation. No permissive power or authority available to
the Preferred Guarantee Trustee shall be construed to be a duty.

SECTION 3.3.     Not Responsible for Recitals or Issuance of Guarantee

         The recitals contained in this Guarantee shall be taken as the
statements of the Guarantor, and the Preferred Guarantee Trustee does not assume
any responsibility for their correctness. The Preferred Guarantee Trustee makes
no representation as to the validity or sufficiency of this Preferred Securities
Guarantee.

                                   ARTICLE IV.
                           PREFERRED GUARANTEE TRUSTEE

SECTION 4.1.     Preferred Guarantee Trustee; Eligibility

         (a)      There shall at all times be a Preferred Guarantee Trustee
which shall:

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<PAGE>

                  (i)      not be an Affiliate of the Guarantor; and

                  (ii) be a corporation organized and doing business under the
         laws of the United States of America or any State or Territory thereof
         or of the District of Columbia, or a corporation or Person permitted by
         the Securities and Exchange Commission to act as an institutional
         trustee under the Trust Indenture Act, authorized under such laws to
         exercise corporate trust powers, having a combined capital and surplus
         of at least 50 million U.S. dollars ($50,000,000), and subject to
         supervision or examination by Federal, State, Territorial or District
         of Columbia authority. If such corporation publishes reports of
         condition at least annually, pursuant to law or to the requirements of
         the supervising or examining authority referred to above, then, for the
         purposes of this Section 4.1(a)(ii), the combined capital and surplus
         of such corporation shall be deemed to be its combined capital and
         surplus as set forth in its most recent report of condition so
         published.

         (b) If at any time the Preferred Guarantee Trustee shall cease to be
eligible to so act under Section 4.1(a), the Preferred Guarantee Trustee shall
immediately resign in the manner and with the effect set out in Section 4.2 (c).

         (c) If the Preferred Guarantee Trustee has or shall acquire any
"conflicting interest" within the meaning of Section 310(b) of the Trust
Indenture Act, the Preferred Guarantee Trustee and Guarantor shall in all
respects comply with the provisions of Section 310(b) of the Trust Indenture
Act.

SECTION 4.2.     Appointment, Removal and Resignation of Preferred Guarantee
Trustees

         (a) Subject to Section 4.2(b), the Preferred Guarantee Trustee may be
appointed or removed without cause at any time by the Guarantor.

         (b) The Preferred Guarantee Trustee shall not be removed in accordance
with Section 4.2(a) until a Successor Preferred Guarantee Trustee has been
appointed and has accepted such appointment by written instrument executed by
such Successor Preferred Guarantee Trustee and delivered to the Guarantor.

         (c) The Preferred Guarantee Trustee appointed to office shall hold
office until a Successor Preferred Guarantee Trustee shall have been appointed
or until its removal or resignation. The Preferred Guarantee Trustee may resign
from office (without need for prior or subsequent accounting) by an instrument
in writing executed by the Preferred Guarantee Trustee and delivered to the
Guarantor, which resignation shall not take effect until a Successor Preferred
Guarantee Trustee has been appointed and has accepted such appointment by
instrument in writing executed by such Successor Preferred Guarantee Trustee and
delivered to the Guarantor and the resigning Preferred Guarantee Trustee.

         (d) If no Successor Preferred Guarantee Trustee shall have been
appointed and accepted appointment as provided in this Section 4.2 within 60
days after delivery to the

                                    -11-

<PAGE>

Guarantor of an instrument of resignation, the resigning Preferred Guarantee
Trustee may petition any court of competent jurisdiction for appointment of a
Successor Preferred Guarantee Trustee. Such court may thereupon, after
prescribing such notice, if any, as it may deem proper, appoint a Successor
Preferred Guarantee Trustee.

         (e) No Preferred Guarantee Trustee shall be liable for the acts or
omissions to act of any Successor Preferred Guarantee Trustee.

         (f) Upon termination of this Preferred Securities Guarantee or removal
or resignation of the Preferred Guarantee Trustee pursuant to this Section 4.2,
the Guarantor shall pay to the Preferred Guarantee Trustee all amounts accrued
to the date of such termination, removal or resignation.

                                   ARTICLE V.
                                    GUARANTEE

SECTION 5.1.     Guarantee

         The Guarantor irrevocably and unconditionally agrees to pay in full to
the Holders the Guarantee Payments (without duplication of amounts theretofore
paid by the Issuer), as and when due, regardless of any defense, right of
set-off or counterclaim that the Issuer may have or assert. The Guarantor's
obligation to make a Guarantee Payment may be satisfied by direct payment of the
required amounts by the Guarantor to the Holders or by causing the Issuer to pay
such amounts to the Holders.

SECTION 5.2.     Waiver of Notice and Demand

         The Guarantor hereby waives notice of acceptance of this Preferred
Securities Guarantee and of any liability to which it applies or may apply,
presentment, demand for payment, any right to require a proceeding first against
the Issuer or any other Person before proceeding against the Guarantor, protest,
notice of nonpayment, notice of dishonor, notice of redemption and all other
notices and demands.

SECTION 5.3.     Obligations Not Affected

         The obligations, covenants, agreements and duties of the Guarantor
under this Preferred Securities Guarantee shall in no way be affected or
impaired by reason of the happening from time to time of any of the following:

         (a) the release or waiver, by operation of law or otherwise, of the
performance or observance by the Issuer of any express or implied agreement,
covenant, term or condition relating to the Preferred Securities to be performed
or observed by the Issuer;

                                      -12-

<PAGE>

         (b) the extension of time for the payment by the Issuer of all or any
portion of the Distributions, Redemption Price, Liquidation Distribution or any
other sums payable under the terms of the Preferred Securities or the extension
of time for the performance of any other obligation under, arising out of, or in
connection with, the Preferred Securities (other than an extension of time for
payment of Distributions, Redemption Price, Liquidation Distribution or other
sum payable that results from the extension of any interest payment period on
the Debentures or any extension of the maturity date of the Debentures permitted
by the Indenture);

         (c) any failure, omission, delay or lack of diligence on the part of
the Holders to enforce, assert or exercise any right, privilege, power or remedy
conferred on the Holders pursuant to the terms of the Preferred Securities, or
any action on the part of the Issuer granting indulgence or extension of any
kind;

         (d) the voluntary or involuntary liquidation, dissolution, sale of any
collateral, receivership, insolvency, bankruptcy, assignment for the benefit of
creditors, reorganization, arrangement, composition or readjustment of debt of,
or other similar proceedings affecting, the Issuer or any of the assets of the
Issuer;

         (e)      any invalidity of, or defect or deficiency in, the Preferred
                  Securities;

         (f)      the settlement or compromise of any obligation guaranteed
                  hereby or hereby incurred; or

         (g) any other circumstance whatsoever that might otherwise constitute a
legal or equitable discharge or defense of a guarantor, it being the intent of
this Section 5.3 that the obligations of the Guarantor hereunder shall be
absolute and unconditional under any and all circumstances.

         There shall be no obligation of the Holders to give notice to, or
obtain consent of, the Guarantor with respect to the happening of any of the
foregoing.

SECTION 5.4.     Rights of Holders

         (a) The Holders of a Majority in liquidation amount of the Preferred
Securities have the right to direct the time, method and place of conducting of
any proceeding for any remedy available to the Preferred Guarantee Trustee in
respect of this Preferred Securities Guarantee or exercising any trust or power
conferred upon the Preferred Guarantee Trustee under this Preferred Securities
Guarantee.

         (b) If the Preferred Guarantee Trustee fails to enforce this Preferred
Securities Guarantee, any Holder of Preferred Securities may institute a legal
proceeding directly against the Guarantor to enforce its rights under this
Preferred Securities Guarantee, without first instituting a legal proceeding
against the Issuer, the Preferred Guarantee Trustee or any other Person.
Notwithstanding the foregoing, if the Guarantor has failed to make a Guarantee

                                      -13-

<PAGE>

Payment, a holder of Preferred Securities may directly institute a proceeding
against the Guarantor for enforcement of the Preferred Security Guarantee for
such payment.

SECTION 5.5.     Guarantee of Payment

         This Preferred Securities Guarantee creates a guarantee of payment and
not of collection.

SECTION 5.6.     Subrogation

         The Guarantor shall be subrogated to all (if any) rights of the Holders
of Preferred Securities against the Issuer in respect of any amounts paid to
such Holders by the Guarantor under this Preferred Securities Guarantee;
provided, however, that the Guarantor shall not (except to the extent required
by mandatory provisions of law) be entitled to enforce or exercise any right
that it may acquire by way of subrogation or any indemnity, reimbursement or
other agreement, in all cases as a result of payment under this Preferred
Securities Guarantee, if, at the time of any such payment, any amounts are due
and unpaid under this Preferred Securities Guarantee. If any amount shall be
paid to the Guarantor in violation of the preceding sentence, the Guarantor
agrees to hold such amount in trust for the Holders and to pay over such amount
to the Holders.

SECTION 5.7.     Independent Obligations

         The Guarantor acknowledges that its obligations hereunder are
independent of the obligations of the Issuer with respect to the Preferred
Securities, and that the Guarantor shall be liable as principal and as debtor
hereunder to make Guarantee Payments pursuant to the terms of this Preferred
Securities Guarantee notwithstanding the occurrence of any event referred to in
subsections (a) through (g), inclusive, of Section 5.3 hereof.

                                   ARTICLE VI.
                    LIMITATION OF TRANSACTIONS; SUBORDINATION

SECTION 6.1.     Limitation of Transactions

         So long as any Preferred Securities remain outstanding, if there shall
have occurred an Event of Default or an event of default under the Declaration,
then (a) the Guarantor shall not declare or pay any dividend on, make any
distributions with respect to, or redeem, purchase, acquire or make a
liquidation payment with respect to, any of its capital stock (other than (i)
purchases or acquisitions of shares of its common stock in connection with the
satisfaction by the Guarantor of its obligations under any employee benefit
plans or the satisfaction by the Guarantor of its obligations pursuant to any
contract or security requiring the Guarantor to purchase shares of its common
stock, (ii) as a result of a reclassification of its capital stock or the
exchange or conversion of one class or series of its capital stock for another
class or series of its capital stock or, (iii) the purchase of fractional
interests in shares of its capital stock pursuant to the conversion or exchange
provisions of such capital stock or security being

                                     -14-

<PAGE>

converted or exchanged) or make any guarantee payment with respect thereto,
(b) the Guarantor shall not make any payment of interest, principal or
premium, if any, on or repay, repurchase or redeem any debt securities
(including guarantees) issued by the Guarantor which rank pari passu with or
junior to the Debentures or (c) the Guarantor shall not make any guarantee
payments with respect to the foregoing (other than pursuant to the Preferred
Securities Guarantee Agreement).

SECTION 6.2.     Ranking

         This Preferred Securities Guarantee will constitute an unsecured
obligation of the Guarantor and will rank (i) subordinate and junior in right of
payment to all other liabilities of the Guarantor except those liabilities of
the Guarantor made pari passu or subordinate by their terms, (ii) pari passu
with the most senior preferred or preference stock now or hereafter issued by
the Guarantor and with any guarantee now or hereafter entered into by the
Guarantor in respect of any preferred or preference stock of any Affiliate of
the Guarantor, and (iii) senior to the Guarantor's common stock.

                                  ARTICLE VII.
                                   TERMINATION

SECTION 7.1.     Termination

         This Preferred Securities Guarantee shall terminate upon (i) full
payment of the Redemption Price of all Preferred Securities, (ii) upon the
distribution of the Debentures to the Holders of all of the Preferred Securities
or (iii) upon full payment of the amounts payable in accordance with the
Declaration upon liquidation of the Issuer. Notwithstanding the foregoing, this
Preferred Securities Guarantee will continue to be effective or will be
reinstated, as the case may be, if at any time any Holder of Preferred
Securities must restore payment of any sums paid under the Preferred Securities
or under this Preferred Securities Guarantee.

                                  ARTICLE VIII.
                                 INDEMNIFICATION

SECTION 8.1.     Exculpation

         (a) No Indemnified Person shall be liable, responsible or accountable
in damages or otherwise to the Guarantor or any Covered Person for any loss,
damage or claim incurred by reason of any act or omission performed or omitted
by such Indemnified Person in good faith in accordance with this Preferred
Securities Guarantee and in a manner that such Indemnified Person reasonably
believed to be within the scope of the authority conferred on such Indemnified
Person by this Preferred Securities Guarantee or by law, except that an
Indemnified Person shall be liable for any such loss, damage or claim incurred
by reason of such Indemnified Person's negligence or willful misconduct with
respect to such acts or omissions.

                                     -15-

<PAGE>

         (b) An Indemnified Person shall be fully protected in relying in good
faith upon the records of the Guarantor and upon such information, opinions,
reports or statements presented to the Guarantor by any Person as to matters the
Indemnified Person reasonably believes are within such other Person's
professional or expert competence and who has been selected with reasonable care
by or on behalf of the Guarantor, including information, opinions, reports or
statements as to the value and amount of the assets, liabilities, profits,
losses, or any other facts pertinent to the existence and amount of assets from
which Distributions to Holders of Preferred Securities might properly be paid.

SECTION 8.2.     Indemnification

         (a) To the fullest extent permitted by applicable law, the Guarantor
shall indemnify and hold harmless each Indemnified Person from and against any
loss, damage or claim incurred by such Indemnified Person by reason of any act
or omission performed or omitted by such Indemnified Person in good faith in
accordance with this Guarantee Agreement and in a manner such Indemnified Person
reasonably believed to be within the scope of authority conferred on such
Indemnified Person by this Guarantee Agreement, except that no Indemnified
Person shall be entitled to be indemnified in respect of any loss, damage or
claim incurred by such Indemnified Person by reason of negligence or willful
misconduct with respect to such acts or omissions.

         (b) To the fullest extent permitted by applicable law, reasonable
expenses (including legal fees) incurred by an Indemnified Person in defending
any claim, demand, action, suit or proceeding shall, from time to time, be
advanced by the Guarantor prior to the final disposition of such claim, demand,
action, suit or proceeding upon receipt by the Guarantor of an undertaking by or
on behalf of the Indemnified Person to repay such amount if it shall be
determined that the Indemnified Person is not entitled to be indemnified as
authorized in Section 8.2(a).

         (c) The obligation to indemnify as set forth in this Section 8.2 shall
survive the termination of the Preferred Securities Guarantee.

                                   ARTICLE IX.
                                  MISCELLANEOUS

SECTION 9.1.     Successors and Assigns

         All guarantees and agreements contained in this Preferred Securities
Guarantee shall bind the successors, assigns, receivers, trustees and
representatives of the Guarantor and shall inure to the benefit of the Holders
of the Preferred Securities then outstanding.

SECTION 9.2.     Amendments

                                      -16-

<PAGE>

         Except with respect to any changes that do not adversely affect the
rights of Holders (in which case no consent of Holders will be required), this
Preferred Securities Guarantee may only be amended with the prior approval of
the Holders of at least a Majority in liquidation amount (including the stated
amount that would be paid on redemption, liquidation or otherwise, plus accrued
and unpaid Distributions to the date upon which the voting percentages are
determined) of all the outstanding Preferred Securities. The provisions of
Section 12.2 of the Declaration with respect to meetings of Holders of the
Securities apply to the giving of such approval.

SECTION 9.3.     Notices

         All notices provided for in this Preferred Securities Guarantee shall
be in writing, duly signed by the party giving such notice, and shall be
delivered, telecopied or mailed by registered or certified mail, as follows:

         (a) if given to the Preferred Guarantee Trustee, at the Preferred
Guarantee Trustee's mailing address set forth below (or such other address as
the Preferred Guarantee Trustee may give notice of to the Holders of the
Preferred Securities):

                            Wilmington Trust Company
                            Rodney Square North
                            1100 North Market Street
                            Wilmington, Delaware 19890
                            Attention:  Corporate Trust Administration

         (b) If given to the Guarantor, at the Guarantor's mailing address set
forth below (or such other address as the Guarantor may give notice of to the
Holders of the Preferred Securities):

                          Northern States Power Company
                          414 Nicollet Mall
                          Minneapolis, Minnesota 55401
                          Attention:  Chief Financial Officer

         (c) If given to any Holder of Preferred Securities, at the address set
forth on the books and records of the Issuer.

         All such notices shall be deemed to have been given when received in
person, telecopied with receipt confirmed, or mailed by first class mail,
postage prepaid except that if a notice or other document is refused delivery or
cannot be delivered because of a changed address of which no notice was given,
such notice or other document shall be deemed to have been delivered on the date
of such refusal or inability to deliver.

SECTION 9.4.     Benefit

                                      -17-

<PAGE>

         This Preferred Securities Guarantee is solely for the benefit of the
Holders of the Preferred Securities and, subject to Section 3.1(a), is not
separately transferable from the Preferred Securities.

SECTION 9.5.     Governing Law

         THIS PREFERRED SECURITIES GUARANTEE SHALL BE GOVERNED BY, AND CONSTRUED
AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF MINNESOTA.

                                      -18-

<PAGE>

         THIS PREFERRED SECURITIES GUARANTEE is executed as of the day and year
first above written.

                             NORTHERN STATES POWER COMPANY, as
                             Guarantor

                             By:
                                ----------------------------------------------
                             Name:    Edward J. McIntyre
                             Title:   Vice President & Chief Financial Officer

                             WILMINGTON TRUST COMPANY, as Preferred
                             Guarantee Trustee

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

                                      -19-<PAGE>

                                  Exhibit 4.57

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

                          SECOND SUPPLEMENTAL INDENTURE

                           Dated as of August 18, 2000

                                      among

                                XCEL ENERGY INC.

                                   AS ISSUER,

                         NORTHERN STATES POWER COMPANY,

                                  AS CO-OBLIGOR

                                       and

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

                                   AS TRUSTEE

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

<PAGE>

                                  TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                             Page
                                                                             ----
<S>                                                                          <C>
ARTICLE I.        RELATION TO INDENTURE; DEFINITIONS...........................2

     SECTION 1.1...............................................................2
     SECTION 1.2...............................................................2

ARTICLE II.       CONVEYANCE AND ASSUMPTION....................................3

     SECTION 2.1...............................................................3

ARTICLE III.      AMENDMENT....................................................3

     SECTION 3.1...............................................................3
     SECTION 3.2...............................................................3

ARTICLE IV.       MISCELLANEOUS................................................3

     SECTION 4.1...............................................................3
     SECTION 4.2...............................................................3
     SECTION 4.3...............................................................4
     SECTION 4.4...............................................................4
     SECTION 4.5...............................................................4
     SECTION 4.6...............................................................4
</TABLE>

                                       i

<PAGE>

     SECOND SUPPLEMENTAL INDENTURE, dated as of August 18, 2000 (the "Second
Supplemental Indenture"), among XCEL ENERGY INC. (formerly Northern States Power
Company), a corporation duly organized and existing under the laws of the State
of Minnesota, having its principal office at 414 Nicollet Mall, Minneapolis,
Minnesota 55401, (the "Company"), Northern STATES Power Company (formerly
Northern Power Corporation), a corporation duly organized and existing under the
laws of the State of Minnesota (the "Co-Obligor") and WELLS FARGO BANK
MINNESOTA, NATIONAL ASSOCIATION (formerly, NORWEST BANK MINNESOTA, NATIONAL
ASSOCIATION), as trustee (the "Trustee").

     WHEREAS, the Company has heretofore executed and delivered its Indenture
(hereinafter referred to as the "Original Indenture"), dated as of January 30,
1997 (the "Original Indenture");

     WHEREAS, the Company has heretofore executed and delivered a First
Supplemental Indenture (the Original Indenture and the First Supplemental
Indenture are hereinafter referred to collectively as the "Indenture"), dated as
of January 31, 1997, which created a series of Securities designated 7-7/8%
Junior Subordinated Debentures due 2037 (the "Debentures");

     WHEREAS, NSP Financing I, a Delaware statutory business trust (the
"Trust"), has offered to the public $200 million aggregate liquidation amount of
its 7-7/8% Trust Originated Preferred Securities (the "Preferred Securities"),
representing undivided beneficial interests in the assets of the Trust and has
invested the proceeds from such offering, together with the proceeds of the
issuance and sale by the Trust to the Company of $6.19 million aggregate
liquidation amount of its 7-7/8% Trust Originated Common Securities, in $206.19
million aggregate principal amount of the Debentures;

     WHEREAS, Section 9.01 of the Indenture provides that the Company and the
Trustee may enter into indentures supplemental thereto for the purposes, among
others, of making any change that does not materially adversely affect the
interests of the Holders of Securities of any series;

     WHEREAS, the Company and the Co-Obligor are parties to an Assignment and
Assumption Agreement dated as of August 18, 2000 (the "Agreement") pursuant to
which the Company shall convey substantially all of its assets to the Co-Obligor
other than the capital stock of certain of the Company's subsidiaries which the
Company owns (the "Conveyance of Assets") and the Co-Obligor shall assume
substantially all of the liabilities of the Company, including liabilities
created under the Indenture (the "Assumption of Liabilities");

     WHEREAS, each of the Company and the Co-Obligor is a corporation validly
existing under the laws of the State of Minnesota;

                                      1

<PAGE>

     WHEREAS, the Board of Directors of Co-Obligor has duly authorized the
assumption of all the covenants, conditions, liabilities and obligations of the
Company under the Indenture;

     WHEREAS, immediately after consummation of the Conveyance of Assets and
Assumption of Liabilities in accordance with the Agreement, no Event of Default
or Default (as defined in the Indenture) shall have occurred and be continuing;

     WHEREAS, the execution and delivery of this Second Supplemental Indenture
has been duly authorized by a resolution adopted by the respective Board of
Directors of the Company and Co-Obligor and each of the Company and Co-Obligor
has agreed to be bound by the provisions hereof;

     WHEREAS, Article Eight of the Indenture permits the Company to sell,
assign, transfer or lease all or substantially all of the properties and assets
of the Company as an entirety or substantially as an entirety, provided that the
Person (as defined in the Indenture) (or group of affiliated Persons) to which
all or substantially all the properties and assets of the Company as an entirety
or substantially as an entirety are sold, assigned, transferred or leased shall
expressly assume, by an indenture supplemental to the Indenture, executed and
delivered to the Trustee, in form satisfactory to the Trustee, all of the
obligations of the Company under the Securities and the Indenture;

     WHEREAS, Co-Obligor desires to assume the obligations of the Company as a
joint and several obligor with the Company under the Indenture and all
Securities (as defined in the Indenture) issued thereunder; and

     WHEREAS, the Trustee has duly determined to execute this Second
Supplemental Indenture and to be bound, insofar as it may lawfully do so, by the
provisions hereof.

     NOW THEREFORE, the Company and Co-Obligor, in consideration of the premises
and of one dollar duly paid to them by the Trustee at or before the execution
and delivery of these presents, the receipt of which is hereby acknowledged, and
in order to secure the payment, of both the principal and interest, of all
Securities at any time outstanding according to their tenor and effect and the
performance of and compliance with the covenants and conditions contained in the
Indenture, covenant and agree with the Trustee for the equal and proportionate
benefit of the holders from time to time of the Securities, as follows:

                                   ARTICLE I.
                       RELATION TO INDENTURE; DEFINITIONS

         SECTION 1.1.     This Second Supplemental Indenture constitutes an
integral part of the Indenture.

                                      2

<PAGE>

         SECTION 1.2.     For all purposes of this Second 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 Second Supplemental Indenture; and

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

                                   ARTICLE II.
                            CONVEYANCE AND ASSUMPTION

         SECTION 2.1. In accordance with the terms of the Indenture, the
Co-Obligor hereby assumes, jointly and severally with the Company, all the
liabilities and obligations of the Company under the Securities and the
Indenture and agrees to pay, duly and punctually, the principal of and premium
and interest on the Securities, and agrees to perform and fulfill all the
covenants and conditions of the Company under the Securities and Indenture; and
the Co-Obligor shall succeed to, and be substituted for, and may exercise every
right and power of, the Company under the Indenture with the same effect as if
the Co-Obligor had been named with the Company therein and in the Securities.

                                  ARTICLE III.
                                    AMENDMENT

         SECTION 3.1. From and after the date of this Second Supplemental
Indenture, the Indenture is hereby amended so that all references therein to
"Northern States Power Company" or the "Company" are hereby deemed to be
references also to the new "Northern States Power Company" and any successor
thereto.

         SECTION 3.2. On and after the date of this Second Supplemental
Indenture, each reference in the Indenture to "this Indenture," "hereunder,"
"hereof" or words of like import referring to the Indenture, shall mean and be a
reference to the Indenture as amended hereby.

                                   ARTICLE IV.
                                  MISCELLANEOUS

         SECTION 4.1. The recitals of fact herein, except the recital that the
Trustee has duly determined to execute this Second Supplemental Indenture and be
bound, insofar as it may lawfully so do, by the provisions hereof and in the
Securities shall be taken as statements of the Company and the Co-Obligor and
shall not be construed as made by the Trustee.

                                       3

<PAGE>

         SECTION 4.2. This Second Supplemental Indenture shall be construed in
connection with and as a part of the Original Indenture, as supplemented by the
First Supplemental Indenture dated as of January 31, 1997.

         SECTION 4.3.

         (a)      If any provision of this Second Supplemental Indenture limits,
                  qualifies, or conflicts with another provision of the
                  Indenture required to be included in 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 the said Act, such
                  required provisions shall control.

         (b)      In case any one or more of the provisions contained in this
                  Second Supplemental Indenture 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 4.4. Wherever in this Second Supplemental Indenture the word
"Indenture" is used without the prefix, "Original" or "Supplemental," such word
was used intentionally to include in its meaning both the Original Indenture and
all indentures supplemental thereto.

         SECTION 4.5. Wherever in this Second Supplemental Indenture any 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 Second Supplemental Indenture contained by or on behalf of the Company by
or on behalf of the Co-Obligor 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 4.6.

         (a)      This Second 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 Second Supplemental Indenture were
                  formulated, used and inserted in this Second Supplemental
                  Indenture for convenience only and shall not be deemed to
                  affect the meaning or construction of any of the provisions
                  hereof.

         (c)      This Second Supplemental Indenture shall be deemed to be a
                  contract made under the internal laws of the State of
                  Minnesota, and for all purposes shall be construed in
                  accordance with the laws of said State.

                                       4

<PAGE>

                  IN WITNESS WHEREOF, XCEL ENERGY INC. (formerly Northern States
Power Company) has caused this Second Supplemental Indenture to be signed by its
President or a Vice President, and attested by its Secretary or an Assistant
Secretary, NORTHERN STATES POWER COMPANY (formerly Northern Power Corporation)
has caused this Second 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 Second
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 18 day of August, 2000.

                                    XCEL ENERGY INC.

                                    By:
                                       ------------------------------------
                                    Name:    Paul E. Pender
                                    Title:   Vice President & Treasurer

        ATTEST:

        ------------------------------
        Catherine J. Cleveland, Assistant Secretary

                                    NORTHERN STATES POWER COMPANY

                                    By:
                                       ------------------------------------
                                    Name:    Edward J. McIntyre
                                    Title:   Vice President & Chief Financial
                                             Officer

         ATTEST:

        ------------------------------
         Catherine J. Cleveland, Assistant Secretary

                                    WELLS FARGO BANK MINNESOTA,
                                    NATIONAL ASSOCIATION, AS TRUSTEE

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

         ATTEST:

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

                                       5

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00015-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00015-of-00352.parquet"}]]