S-3

As filed with the Securities and Exchange Commission on March 19, 2007

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM S-3

REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

PUBLIC SERVICE COMPANY OF COLORADO

(Exact name of registrant as specified in the charter)

COLORADO	84-0296600
(State or other jurisdiction of	(I.R.S. Employer
incorporation or organization)	Identification No.)

1225 17th Street

Denver, CO 80202-5533

(303) 571-7511

(Address, including zip code, and telephone number, including

area code, of registrant’s principal executive offices)

PATRICIA K. VINCENT

President and Chief Executive Officer

Public Service Company of Colorado

1225 17th Street

Denver, Colorado 80202-5533

(303) 571-7511

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copy to:

ROBERT J. JOSEPH	J. ANTHONY TERRELL
Jones Day	Dewey Ballantine LLP
77 West Wacker	1301 Avenue of the Americas
Chicago, Illinois 60601	New York, New York 10019
(312) 269-4176	(212) 259-7070

Approximate date of commencement of proposed sale to the public:  At such time or times after the
effective date of this registration statement as the registrant shall determine based on market conditions and other factors.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. o

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box. x

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the early effective registration statement for the same offering. o

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. o

If this Form is a post-effective amendment to a registration statement pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. o

CALCULATION OF REGISTRATION FEE

			Proposed maximum		Proposed maximum
Title of each class of	Amount to be		offering		aggregate offering price		Amount of
securities to be registered	registered		price per unit (1)(2)		(1)(2)		registration fee
Senior Debt Securities, First Mortgage Bonds	$	975,000,000	100	%	$	975,000,000	$	29,933.00

(1)Estimated solely for purposes of calculating the registration fee pursuant to Rule 457(o) under the Securities Act.

(2)Exclusive of accrued interest, if any.

Pursuant to Rule 429 under the Securities Act of 1933, as amended, the prospectus contained in this registration statement will be used as a combined prospectus in connection with this registration statement and registration statement No. 333-104504 which was filed by the registrant on April 14, 2003 and declared effective May 8, 2003 (the “Prior Registration Statement”) under which $225,000,000 in principal amount of the registrant’s senior debt securities and first collateral trust bonds (the “Previously Registered Securities”) remain unsold.  This registration statement is a new registration statement and also constitutes Post-Effective Amendment No. 1 to the Prior Registration Statement pursuant to which the total amount of unsold Previously Registered Securities registered on the Prior Registration Statement may be offered and sold as first mortgage bonds or senior debt securities.  Such post-effective amendment will become effective concurrently with the effectiveness of this registration statement in accordance with Section 8(a) of the Securities Act.  In the event that any of such Previously Registered Securities are offered and sold prior to the effective date of this registration statement, the amount of such Previously Registered Securities so sold will not be included in the prospectus hereunder.

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act, or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to Section 8(a), may determine.

SUBJECT TO COMPLETION, DATED MARCH 19, 2007

The information in this prospectus is not complete and may be changed.  We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective.  This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

PROSPECTUS

$1,200,000,000

PUBLIC SERVICE COMPANY OF COLORADO
1225 17th STREET
DENVER, COLORADO 80202-5533
(303) 571-7511

FIRST MORTGAGE BONDS
SENIOR DEBT SECURITIES

We may offer, from time to time, up to $1,200,000,000 aggregate principal amount of our secured first mortgage bonds or unsecured senior debt securities.  We may sell our first mortgage bonds or senior debt securities in one or more series (1) through underwriters or dealers, (2) through agents, or (3) directly to a limited number of institutional purchasers.  See “Plan of Distribution.”  The particular type of security being sold as well as the amount and terms of the sale of a series of our first mortgage bonds or senior debt securities will be determined at the time of sale and described in a prospectus supplement that will accompany this prospectus.  You should read this prospectus and any supplement carefully before you invest.  We cannot sell any of these first mortgage bonds or senior debt securities unless this prospectus is accompanied by a prospectus supplement.  That prospectus supplement will describe if applicable:

·the names of any underwriters, dealers or agents involved in the distribution of that series of first mortgage bonds or senior debt securities;

·any applicable commissions or discounts and the net proceeds to us from that sale;

·the aggregate principal amount and offering price of that series of the first mortgage bonds or senior debt securities;

·the rate or rates (or method of calculation) of interest;

·the time or times and place of payment of interest;

·the maturity date or dates; and

·any redemption terms or other specific terms of that series of first mortgage bonds or senior debt securities.

See “Risk Factors” on page 2 of this prospectus, in the prospectus supplement and in the documents incorporated by reference in this prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is                      , 2007.

As permitted under the rules of the Securities and Exchange Commission, this prospectus incorporates important business information about Public Service Company of Colorado that is contained in documents that we file with the Securities and Exchange Commission but that is not included in or delivered with this prospectus.  You may obtain copies of these documents, without charge, from the website maintained by the Securities and Exchange Commission at www.sec.gov, as well as other sources.  See “Where You Can Find More Information.”

You may also obtain copies of the incorporated documents, without charge, upon written or oral request to the Corporate Secretary, Public Service Company of Colorado, 1225 17^th Street, Suite 900, Denver, Colorado 80202-5533, (303) 571-7511.

You should rely only on the information incorporated by reference or provided in this prospectus.  We have not authorized anyone else to provide you with different information.  We are not making an offer of these securities in any state where the offer is not permitted.  You should not assume that the information in this prospectus or the documents incorporated by reference is accurate as of any date other than the date on the front of those documents.

TABLE OF CONTENTS

RISK FACTORS

Investing in our securities involves risks. Before buying any securities, you should carefully consider the risks and other information we include under the heading “Risk Factors” in our Annual Report on Form 10-K and other documents incorporated by reference in this prospectus.  In addition, you should consider any risks and uncertainties that we may include in the prospectus supplement relating to a specific issue of securities.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and the documents it incorporates by reference contain statements that are not historical fact and constitute “forward-looking statements.”  When we use words like “anticipates,” “believes,” “estimates,” “expects,” “intends,” “plans,” “may,” “should,” or similar expressions, or when we discuss our strategy or plans, we are making forward-looking statements.  Forward-looking statements are not guarantees of performance.  They involve risks, uncertainties and assumptions.  Our future results may differ materially from those expressed in these forward-looking statements.  These statements are necessarily based upon various assumptions involving judgments with respect to the future and other risks.

You are cautioned not to rely unduly on any forward-looking statements.  The risks and uncertainties associated with forward-looking statements are discussed in detail under “Risk Factors,” “Business,” “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and “Notes to Consolidated Financial Statements” in our Annual Report on Form 10-K for the year ended December 31, 2006, and other documents on file with the SEC and incorporated by reference in this prospectus.  You may obtain copies of these documents as described under the caption “Where You Can Find More Information.”

We undertake no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and special reports, and other information with the Securities and Exchange Commission.  Our SEC filings are available to the public over the Internet at the SEC’s web site at http://www.sec.gov.  You may read and copy any document we file with the SEC at the SEC’s Public Reference Room located at 100 F Street, N.E., Washington, D.C. 20549.  Please call the SEC at 1-800-SEC-0330 for further information on the public reference room.

We are “incorporating by reference” the documents that we have filed with the SEC, which means that we are disclosing important information to you by referring you to those documents.  The information incorporated by reference is an important part of this prospectus, and information that we file later with the SEC will automatically update and supersede this information.  We incorporate by reference the documents listed below and any future filings made after the date of the registration statement of which this prospectus is a part made with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, until we sell all of the securities:

·Our Annual Report on Form 10-K for the year ended December 31, 2006, filed with the SEC on February 27, 2007; and

·Our Current Report on Form 8-K filed with the SEC on February 16, 2007.

We are not required to, and do not, provide annual reports to holders of our first mortgage bonds or senior debt securities unless specifically requested by a holder.

This prospectus is part of a registration statement that we have filed with the SEC utilizing a “shelf” registration process. Under this shelf registration process, we may sell the securities described in this prospectus in one or more offerings up to a total dollar amount of $1,200,000,000.  As permitted by SEC rules, this prospectus does not contain all of the information included in the registration statement and the accompanying exhibits and schedules we file with the SEC.  You should read the registration statement, the exhibits and the schedules for more information about us and our securities.  The registration statement, exhibits and schedules are also available at the SEC’s Public Reference Room or through its Internet site.

We will provide without charge to each person, including any beneficial owner, to whom this prospectus is delivered, upon his or her written or oral request, a copy of any or all documents referred to above which have been or may be incorporated by reference into this prospectus excluding exhibits to those documents unless they are specifically incorporated by reference into those documents. You may request those documents from:

Attn:	Corporate Secretary
	Public Service Company of Colorado
	1225 17th Street, Suite 900
	Denver, Colorado 80202-5533
	(303) 571-7511

This prospectus provides you with a general description of the securities we may offer.  Each time we sell securities, we will provide a prospectus supplement that will contain specific information about the terms of that offering.  The prospectus supplement may also add, update or supplement information contained in this prospectus.  You should read this prospectus, the related exhibits filed with the SEC and any prospectus supplement together with additional information described above.

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OUR COMPANY

We were incorporated in 1924 under the laws of the State of Colorado.  We are an operating utility engaged principally in the generation, purchase, transmission, distribution and sale of electricity and the purchase, transportation, distribution and sale of natural gas.  We serve approximately 1.3 million electric customers and approximately 1.3 million gas customers in Colorado.

We own the following direct subsidiaries:  1480 Welton, Inc., which owns certain of our real estate interests; PSR Investments, Inc., which owns and manages permanent life insurance policies on certain of our employees; and Green and Clear Lakes Co., which owns water rights.  We also hold controlling interests in several other relatively small ditch and water companies whose capital requirements are not significant.

We are a wholly-owned subsidiary of Xcel Energy Inc.  Among Xcel Energy’s other subsidiaries are Northern States Power Company, a Minnesota corporation, Southwestern Public Service Company, a New Mexico corporation, and Northern States Power Company, a Wisconsin corporation.  Xcel Energy is a publicly held company and files periodic reports and other documents with the SEC.  A majority of the members of our Board of Directors and many of our executive officers also are executive officers of Xcel Energy.

Our principal executive offices are located at 1225 17th Street, Denver, Colorado 80202-5533 and our telephone number is (303) 571-7511.

USE OF PROCEEDS

Unless otherwise indicated in a prospectus supplement relating to the issue of a particular series of first mortgage bonds or senior debt securities, we intend to use the net proceeds from the sale of the first mortgage bonds or senior debt securities offered hereby for general corporate purposes, including capital expenditures, repayment of short-term debt and refunding of long-term debt on maturity or otherwise.  Our short-term debt aggregated approximately $372.5 million as of December 31, 2006.  The specific allocation of the proceeds of a particular series of the first mortgage bonds or senior debt securities will be described in the prospectus supplement relating to that series.

RATIO OF CONSOLIDATED EARNINGS TO
CONSOLIDATED FIXED CHARGES

	Twelve Months Ended December 31,
	2002	2003	2004	2005	2006
Ratio of consolidated earnings to consolidated fixed charges	2.6	2.2	2.1	2.1	2.2

For purposes of computing the ratio of earnings to fixed charges, (1) earnings consist of income from continuing operations before income taxes plus deferred income taxes and investment tax credits and plus fixed charges; and (2) fixed charges consist of interest charges, including interest on long-term debt, estimated interest within rental expense and amortization of debt discount, premium and expense, and distributions on redeemable preferred securities of subsidiary trust.

DESCRIPTION OF THE FIRST MORTGAGE BONDS

General

We may issue from time to time, in one or more series, the first mortgage bonds as fully registered bonds, without coupons, under an Indenture, dated as of October 1, 1993, between us and U.S. Bank Trust National Association (formerly First Trust of New York, National Association) as successor trustee.  We refer to this Indenture, as supplemented and to be supplemented by various supplemental indentures, including one or more

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supplemental indentures relating to the first mortgage bonds being offered by this prospectus, as the Mortgage Indenture.  We refer to the first mortgage bonds being offered by this prospectus and all other debt securities issued under the Mortgage Indenture as mortgage securities or mortgage bonds. References to business day(s) in this description of the first mortgage bonds means any day, other than a Saturday or Sunday, which is not a day on which banking institutions or trust companies in New York, New York (or any other city in which an office or agency is maintained for the purpose of payment of the first mortgage bonds) are generally authorized or required by law, regulation or executive order to remain closed.  The information we are providing you in this prospectus concerning the mortgage bonds and the Mortgage Indenture is only a summary of the information provided in these documents.  You should consult the mortgage bonds themselves, the Mortgage Indenture and other documents for more complete information on the mortgage bonds.  The Mortgage Indenture is an exhibit to the registration statement and you should read it for provisions that may be important to you.  In the summary below, we have included references to section numbers of the Mortgage Indenture so that you can easily locate these provisions.  Capitalized terms used in the following summary have the meaning specified in the Mortgage Indenture unless otherwise defined below.

The Mortgage Indenture does not limit the amount of debt securities that we may issue under it.  However, we may issue debt securities under the Mortgage Indenture only on the basis of property additions, retired mortgage securities, cash or Class A Bonds (as discussed below).  See “Issuance of Additional Mortgage Securities” for more information about the limitations on the issuance of mortgage securities.  At January 31, 2007, we had $1.703 billion of our first mortgage bonds outstanding.

Prior to October 2005, we issued mortgage securities on the basis of Class A Bonds issued under our Indenture dated as of December 1, 1939 and supplemental indentures thereto (collectively, the “1939 Indenture”).  Effective October 14, 2005, we discharged the 1939 Indenture in accordance with its terms.  As a result, there are no Class A Bonds currently outstanding and the Mortgage Indenture has become the first lien on our electric properties, subject to certain permitted liens, and as described in more detail below.

The holders of outstanding first mortgage bonds do not, and, unless the prospectus supplement that describes a particular series of first mortgage bonds provides otherwise with respect to that series, the holders of any first mortgage bonds offered by this prospectus will not, have the right to require us to repurchase the first mortgage bonds if we become involved in a highly leveraged or change of control transaction. The Mortgage Indenture does not have any provision that is designed specifically in response to highly leveraged or change of control transactions. However, bondholders would have the security afforded as described below under the caption “Security for First Mortgage Bonds.”  In addition, any change in control transaction and any incurrence of substantial additional indebtedness, as first mortgage bonds or otherwise, by us in a transaction of that nature would require approval of state utility regulatory authorities and, possibly, of federal utility regulatory authorities. Management believes that these approvals would be unlikely in any transaction that would result in us, or our successor, having a highly leveraged capital structure.

When we offer to sell a particular series of first mortgage bonds, we will describe the specific terms of that series in a prospectus supplement relating to that series, including the following terms:

·the title of the series;

·any limit on the aggregate principal amount of the series;

·the date or dates on which we will pay the principal of that series;

·the rate or rates at which that series will bear interest or the method of calculating the rate or rates;

·the date or dates from which interest will accrue;

·the dates on which we will pay interest and the regular record dates for the interest payment dates and the persons to whom we will pay interest if different from the person in whose name the first mortgage bonds of that series are registered on the regular record date;

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·any redemption terms, including mandatory redemption through a sinking fund or otherwise, redemption at our option and redemption at the option of the holder;

·the denominations in which we will issue that series, if other than $1,000 and integral multiples of $1,000;

·whether we will issue that series in whole or in part in book-entry form; and

·any other terms of that series of first mortgage bonds, including, if applicable, any consents to modifications or waivers of covenants contained in the Mortgage Indenture or any Class A Mortgage (as discussed below).

Payment of First Mortgage Bonds; Transfers; Exchanges

Unless the prospectus supplement that describes a particular series of first mortgage bonds provides otherwise with respect to that series, we will pay interest, if any, on each first mortgage bond payable on each interest payment date to the person in whose name the first mortgage bond is registered as of the close of business on the regular record date relating to that interest payment date.  We will pay interest payable at maturity (whether at stated maturity, upon redemption or otherwise)  to the person to whom principal is paid at maturity.  If we fail to pay interest on any first mortgage bond when due, we will pay the defaulted interest to the holder of the first mortgage bond as of the close of business on a date selected by the Mortgage Indenture trustee which is not more than 30 days and not less than 10 days prior to the date we propose for payment or in any other lawful manner not inconsistent with the requirements of any securities exchange on which the first mortgage bond may be listed, if the Mortgage Indenture trustee deems the manner of payment practicable.  (See Section 307)

Unless the prospectus supplement that describes a particular series of first mortgage bonds provides otherwise with respect to that series, we will pay the principal of and premium, if any, and interest at maturity upon presentation of the first mortgage bonds at the corporate trust office of U.S. Bank Trust National Association (formerly First Trust of New York, National Association), in New York, New York, as our paying agent.  We may change the place of payment on the bonds.  We may appoint one or more additional paying agents (including us) and may remove any paying agent, all at our discretion.  (See Section 602 and Article One of the Supplemental Indenture(s) relating to the first mortgage bonds.)

Unless the prospectus supplement that describes a particular series of first mortgage bonds provides otherwise with respect to that series, you may register the transfer of first mortgage bonds, and exchange your bonds for other first mortgage bonds of the same series and tranche, of authorized denominations and of like tenor and aggregate principal amount, at the corporate trust office of U.S. Bank Trust National Association (formerly First Trust of New York, National Association), in New York, New York, as security registrar.  We may change the place for registration of transfer and exchange.   We may designate one or more additional places for the registration and exchange, all at our discretion. (See Section 305 and Section 602)

Unless the prospectus supplement that describes a particular series of first mortgage bonds provides otherwise with respect to that series, no service charge will be made for any transfer or exchange of the first mortgage bonds, but we may require payment of a sum sufficient to cover any tax or other governmental charge imposed in connection with any registration of transfer or exchange of the first mortgage bonds.  We are not required to execute or to provide for the registration of transfer of or the exchange of (1) any first mortgage bonds during a period of 15 days prior to giving any notice of redemption or (2) any first mortgage bonds selected for redemption in whole or in part, except the unredeemed portion of any first mortgage bonds being redeemed in part. (See Section 305)

Redemption

The prospectus supplement that describes a particular series of first mortgage bonds will set forth any terms for the optional or mandatory redemption of that particular series.  Unless the prospectus supplement that describes a particular series of first mortgage bonds provides that such series of first mortgage bonds are redeemable at the

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option of a holder, the first mortgage bonds will be redeemable only at our option.  To exercise our option to redeem any such first mortgage bonds that are redeemable at our option, we will mail you a notice of redemption at least 30 days but not more than 60 days prior to the date fixed for redemption.  If we elect to redeem fewer than all the bonds of a series or any tranche of bonds, the security registrar will select the particular bonds to be redeemed by the method provided for any particular series, or if there is no such provision, by a method of random selection that the security registrar deems fair and appropriate.  (See Sections 503 and 504)

Any notice of redemption at our option may state that the redemption will be conditional upon receipt by the paying agent or agents, on or prior to the date fixed for the redemption, of money sufficient to pay the principal, premium, if any, and interest, if any, on the bonds and that if the money has not been so received, the notice will be of no force and effect and we will not be required to redeem the first mortgage bonds. (See Section 504)

While the original Mortgage Indenture contains provisions for the maintenance of the mortgaged property, it does not contain any provisions for a maintenance or sinking fund and, except as the prospectus supplement may provide, there will be no provisions for any maintenance or sinking funds for the first mortgage bonds.

Security

General.Except as discussed under this caption and under “Issuance of Additional Mortgage Securities” below, all mortgage securities now or hereafter issued under the Mortgage Indenture will be secured, equally and ratably, primarily by the lien of the Mortgage Indenture on substantially all of our properties used or to be used in or in connection with the business of generating, purchasing, transmitting, distributing and/or selling electric energy, which lien constitutes, subject to specified exceptions, a first mortgage lien on such properties.

As discussed below under “Class A Bonds,” if we acquire property subject to an existing mortgage and we assume all the obligations of the mortgagor under that mortgage, we could deliver to the Mortgage Indenture trustee bonds issued under that mortgage.  We refer to all such pre-existing mortgages collectively as Class A Mortgages.  If we were to deliver to the Mortgage Indenture trustee bonds issued under a Class A Mortgage, the mortgage securities would be secured by those bonds and, indirectly, by the lien of that Class A Mortgage on the properties subject to such Class A Mortgage in addition to the lien of the Mortgage Indenture on those properties and the other properties of the Company as discussed above.  The lien of the Mortgage Indenture on the properties subject to that Class A Mortgage would be junior to the liens of the Class A Mortgage on those properties.  We refer to all bonds that may be issued under the Class A Mortgages collectively as Class A Bonds.

If and when no Class A Mortgages are in effect, the Mortgage Indenture will constitute a first mortgage lien on all of our property subject to such lien, subject to specified permitted liens (as discussed below under “Lien of the Mortgage Indenture”).  As discussed below under “Class A Bonds,” at the date of this prospectus there are no Class A Mortgages.

Lien of the Mortgage Indenture.  In the opinion of Ryley Carlock & Applewhite, based on information obtained from public records and from us, the Mortgage Indenture constitutes a first mortgage lien on the property specifically or generally described or referred to in the Mortgage Indenture as subject to the lien of the Mortgage Indenture, except any such property as may have been disposed of or released from the lien of the Mortgage Indenture in accordance with the terms of the Mortgage Indenture, subject to no liens prior to the lien of the Mortgage Indenture other than the liens of any other Class A Mortgages and permitted liens.

The Mortgage Indenture effectively subjects to the lien of the Mortgage Indenture property used or to be used in the Electric Utility Business (other than excepted property) that we acquired after the date of the execution and delivery of the Mortgage Indenture to the extent, and subject to the qualifications described below.  In addition, the mortgage securities will have the benefit of the prior lien of any Class A Mortgage on any property subject to such additional Class A Mortgage, to the extent of the aggregate principal amount of Class A Bonds issued under the respective Class A Mortgages and held by the Mortgage Indenture trustee for the benefit of holders of mortgage securities.

The properties subject to the lien of the Mortgage Indenture, whether currently owned or subsequently acquired, are our properties used or to be used in or in connection with our electric utility business (whether or not

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this is the sole use of the properties).  Properties relating to our gas and steam businesses are not subject to the lien of the Mortgage Indenture.

The lien of the Mortgage Indenture is subject to permitted liens which include:

·tax liens and other governmental charges which are not delinquent or which are being contested in good faith;

·specified workmen’s, materialmen’s and other similar liens;

·specified judgment liens and attachments; specified easements, leases, reservations or other rights of others (including governmental entities) in, on, over, and/or across, and laws, regulations and restrictions affecting, and defects, irregularities, exceptions and limitations in title to, some of our property;

·specified leasehold interests;

·specified rights and interests of others which relate to common ownership or joint use of property and liens on the interests of others in the property;

·specified non-exclusive rights and interests that we retain with respect to property used or to be used in or in connection with both the businesses in which the mortgaged property is used and any other businesses; and

·specified other liens and encumbrances.

(See Granting Clauses and Section 101)

There are excepted from the lien of the Mortgage Indenture, among other things:

·cash and securities not paid or delivered to, deposited with or held by the Mortgage Indenture trustee under the Mortgage Indenture;

·all contracts, leases and other agreements of whatsoever kind, contract rights, bills, notes and other instruments, accounts receivable, claims, governmental and other permits, allowances and franchises, specified intellectual property rights and other intangibles;

·automobiles, other vehicles, movable equipment and aircraft;

·goods, stock in trade, wares and merchandise held for sale or lease in the ordinary course of business;

·materials, supplies and other personal property consumable in the operation of the mortgaged property;

·fuel, including nuclear fuel, whether or not consumable in the operation of the mortgaged property;

·furniture and furnishings; computers, machinery and telecommunication and other equipment used exclusively for corporate administrative or clerical purposes;

·coal, ore, gas, oil and other minerals and timber, and rights and interests in any such minerals or timber, whether or not the minerals or timber have been mined or extracted or otherwise separated from the land;

·electric energy, gas (natural or artificial), steam, water and other products that we generated, produced, manufactured, purchased or otherwise acquired; and

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·leasehold interests that we hold as lessee; and any of our property that is located outside of the State of Colorado.

(See “Excepted Property” in Granting Clauses)

Without the consent of the holders, we and the Mortgage Indenture trustee may enter into supplemental indentures in order to subject to the lien of the Mortgage Indenture additional property, whether or not used or to be used in or in connection with the electric utility business (including property which would otherwise be excepted from the lien).  (See Section 1401)  Any such additional property would then constitute property additions (so long as it would otherwise qualify as “property additions” as described below) and be available as a basis for the issuance of mortgage securities.  See “Issuance of Additional Mortgage Securities.”

As discussed above, the Mortgage Indenture subjects after-acquired property used or to be used in the electric utility business to its lien.  These provisions are limited in the case of consolidation or merger (whether or not we are the surviving corporation) or transfer of the mortgaged property as, or substantially as, an entirety.  In the event of consolidation or merger or the transfer of the mortgaged property as or substantially as an entirety, the Mortgage Indenture will not be required to be a lien upon any of the properties then owned or subsequently acquired by the successor corporation except properties acquired from us in or as a result of the transaction and improvements, extensions and additions to the properties and renewals, replacements and substitutions of or for any part or parts of the properties.  (See Article 13 and “Consolidation, Merger, etc.”)  In addition, after-acquired property may be subject to liens existing or placed on the after-acquired property at the time of acquisition of the property, including, but not limited to, purchase money liens and the lien of any Class A Mortgage.

The Mortgage Indenture trustee has a lien, prior to the lien on behalf of the holders of mortgage securities, upon the mortgaged property for the payment of its reasonable compensation and expenses and for indemnity against specified liabilities.  (See Section 1107)

Issuance of Additional Mortgage Securities

General.  Except as described below, the aggregate principal amount of mortgage securities which we can issue under the Mortgage Indenture is unlimited.  (See Section 301)  We can issue mortgage securities of any series from time to time on the basis of, and in an aggregate principal amount not exceeding the sum of:

·70% of the cost or fair value to us (whichever is less) of property additions which do not constitute funded property after specified deductions and additions, primarily including adjustments to offset property retirements.  Property additions generally include any property which we own and are subject to the lien of the Mortgage Indenture except goodwill, going concern value rights or intangible property, or any property the cost of acquisition or construction of which is properly chargeable to one of our operating expense accounts.  (See Section 104)  Funded property is generally property additions that have been:

·made the basis of the authentication and delivery of mortgage securities, the release of mortgaged property or cash withdrawals;

·substituted for retired property; or

·used as the basis of a credit against, or otherwise in satisfaction of, any sinking, improvement, maintenance, replacement or similar fund, provided that mortgage securities of the series or tranche to which the fund relates remain outstanding;

·the aggregate principal amount of retired mortgage securities (which consist of mortgage securities no longer outstanding under the Mortgage Indenture which have not been used for specified other purposes under the Mortgage Indenture and which have not been paid, redeemed or otherwise retired by the application of funded cash), but if Class A Bonds had been made the basis for the authentication

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and delivery of the retired mortgage securities, only if the retired mortgage securities became retired securities after the discharge of the related Class A Mortgage;

·an amount of cash deposited with the Mortgage Indenture trustee; and

·the aggregate principal amount of any Class A Bonds issued and delivered to the Mortgage Indenture trustee.

(See Article Four)

As of December 31, 2006, the approximate amount of property additions and the amount of retired bonds available for use as the basis for the issuance of mortgage securities were $4.2 billion and $259.5 million, respectively.

Net Earnings Test.  In general, we cannot issue any mortgage securities unless at that time our adjusted net earnings for 12 consecutive months within the preceding 18 months is at least twice the annual interest requirements on the sum of:

·all mortgage securities at the time outstanding;

·new mortgage securities then being applied for;

·all outstanding Class A Bonds other than Class A Bonds held by the Mortgage Indenture trustee under the Mortgage Indenture; and

·all other indebtedness (with certain exceptions) secured by a lien prior to the lien of the Mortgage Indenture.

For purposes of calculating our interest requirements, any variable rate debt will be computed based on the rates in effect at the time we make the interest requirements calculation.

Adjusted net earnings are calculated before, among other things, provisions for income taxes; depreciation or amortization of property; interest and amortization of debt discount and expense; any non-recurring charge to income or retained earnings; and any refund of revenues that we previously collected or accrued subject to possible refund.  In addition, profits or losses from the sale or other disposition of property, or non-recurring items of revenue, income or expense are not included for purposes of calculating adjusted net earnings. (See Sections 103 and 401)

We do not have to satisfy the net earnings requirement if the additional mortgage securities to be issued will not have a stated interest rate prior to maturity.  In addition, we are not required to satisfy the net earnings requirement prior to issuance of mortgage securities:

·issued on the basis of the delivery of Class A Bonds if the Class A Bonds have been authenticated and delivered under the related Class A Mortgage on the basis of retired Class A Bonds; or

·issued on the basis of retired mortgage securities as described above.

For mortgage securities of a series subject to a periodic offering (such as a medium-term note program), the Mortgage Indenture trustee will be entitled to receive a certificate evidencing compliance with the net earnings requirements only once, at or prior to the time of the first authentication and delivery of the mortgage securities of the series.  (See Article Four)

At December 31, 2006, our adjusted net earnings would be 3.89 times the annual interest requirements on our mortgage securities, including the first mortgage bonds that we could issue pursuant to this prospectus at an assumed interest rate of 6.0%.

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Class A Bonds. To the extent that we issue the first mortgage bonds on the basis of Class A Bonds, the Mortgage Indenture trustee will own and hold these Class A Bonds, subject to the provisions of the Mortgage Indenture, for the benefit of the holders of all mortgage securities outstanding from time to time, and we will have no interest in the Class A Bonds.  Class A Bonds issued as the basis of authentication and delivery of a series of mortgage securities:

·will mature or be subject to mandatory redemption on the same dates, and in the same principal amounts, as the mortgage securities of that series; and

·will contain, in addition to any mandatory redemption provisions applicable to all Class A Bonds outstanding under the related Class A Mortgage, mandatory redemption provisions correlative to provisions for mandatory redemption of the mortgage securities (pursuant to a sinking fund or otherwise) of that series, or for redemption at the option of the holder of the mortgage securities of that series.

Class A Bonds issued as the basis for the authentication and delivery of mortgage securities are not required to bear interest. To the extent that any such Class A Bonds do not bear interest, holders of mortgage securities will not have the benefit of the lien of the Class A Mortgage in respect of an amount equal to accrued interest, if any, on the first mortgage bonds; however, those holders will have the benefit of the lien of the Mortgage Indenture in respect of that amount.

The Mortgage Indenture trustee will apply any of our payments of principal, premium or interest on the Class A Bonds held by the Mortgage Indenture trustee to the payment of any principal, premium or interest, as the case may be, in respect of the mortgage securities which is then due.  Our obligation under the Mortgage Indenture to make the payment in respect of the mortgage securities will thereupon be deemed satisfied and discharged.  If, at the time of any payment of principal of Class A Bonds, no principal is then due in respect of the mortgage securities, the payment in respect of the Class A Bonds will be deemed to constitute funded cash and will be held by the Mortgage Indenture trustee as part of the mortgaged property, to be withdrawn, used or applied as provided in the Mortgage Indenture.  Any payment by us of principal, premium or interest on the mortgage securities authenticated and delivered on the basis of the issuance and delivery to the Mortgage Indenture trustee of Class A Bonds (other than by application of the proceeds of a payment in respect of the Class A Bonds) will be deemed to satisfy and discharge our obligation to make a payment of principal, premium or interest, in respect of the Class A Bonds which is then due.  (See Section 702)

The Mortgage Indenture trustee may not sell, assign or otherwise transfer any Class A Bonds except to a successor trustee under the Mortgage Indenture.  (See Section 704)  At the time any mortgage securities of any series or tranche which have been authenticated and delivered upon the basis of the issuance and delivery to the Mortgage Indenture trustee of Class A Bonds cease to be outstanding (other than as a result of the application of the proceeds of the payment or redemption of the Class A Bonds), the Mortgage Indenture trustee will surrender to us an equal principal amount of those Class A Bonds.  (See Section 703)

Under the terms of the Mortgage Indenture, if a corporation which was a mortgagor under a mortgage has merged into or consolidated with us, or has conveyed or otherwise transferred property to us subject to the lien of such a mortgage and we have assumed all the obligations of the mortgagor under such existing mortgage, and in either case such existing mortgage constitutes a lien on properties of such other corporation or on the transferred properties, as the case may be, prior to the lien of the Mortgage Indenture, we may designate the existing mortgage as a Class A Mortgage.  Bonds subsequently issued under an additional mortgage would be Class A Bonds and could provide the basis for the authentication and delivery of mortgage securities. (See Section 706)  When no Class A Bonds are outstanding under a Class A Mortgage except for Class A Bonds held by the Mortgage Indenture trustee, then, at our request and subject to satisfaction of specified conditions, the Mortgage Indenture trustee will surrender the Class A Bonds for cancellation and the related Class A Mortgage will be satisfied and discharged, the lien of the Class A Mortgage on our property will cease to exist and the priority of the lien of the Mortgage Indenture will be increased accordingly.  (See Section 707)

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The Mortgage Indenture contains no restrictions on the issuance of Class A Bonds in addition to Class A Bonds issued to the Mortgage Indenture trustee as the basis for the authentication and delivery of the mortgage securities.

Release of Property

Unless an event of default under the Mortgage Indenture has occurred and is continuing, we may obtain the release from the lien of the Mortgage Indenture of any funded property, except for cash held by the Mortgage Indenture trustee, by delivering to the Mortgage Indenture trustee cash equal to the cost of the property to be released (or, if less, the fair value to us of the property at the time it became funded property) less the aggregate of:

·the aggregate principal amount of obligations delivered to the Mortgage Indenture trustee which are secured by purchase money liens upon the property to be released;

·the cost or fair value to us (whichever is less) of certified property additions not constituting funded property after specified deductions and additions, primarily including adjustments to offset property retirements (except that the adjustments need not be made if the property additions were acquired or made within the 90-day period preceding the release);

·an amount equal to 10/7ths of the principal amount of mortgage securities we would be entitled to issue on the basis of retired securities (with our right to issue a corresponding principal amount of mortgage securities being waived);

·an amount equal to 10/7ths of the principal amount of outstanding mortgage securities delivered to the Mortgage Indenture trustee (with the mortgage securities to be cancelled by the Mortgage Indenture trustee);

·an amount of cash and/or the aggregate principal amount of obligations secured by purchase money liens upon the property to be released, which in either case is evidenced to the Mortgage Indenture trustee by a certificate of the trustee or other holder of a lien prior to the lien of the Mortgage Indenture to have been received by the trustee or other holder in consideration for the release of the property or any part of the property from the lien; subject in either case to specified limitations on the aggregate credit which may be used; and

·any taxes and expenses incidental to any sale, exchange, dedication or other disposition of the property to be released.

Property which is not funded property may generally be released from the lien of the Mortgage Indenture without depositing any cash or property with the Mortgage Indenture trustee as long as:

·the aggregate amount of cost or fair value to us (whichever is less) of all property additions which do not constitute funded property (excluding the property to be released) after specified deductions and additions, primarily including adjustments to offset property retirements, is greater than zero; or

·the cost or fair value (whichever is less) of property to be released does not exceed the aggregate amount of the cost or fair value to us (whichever is less) of property additions acquired or made within the 90-day period preceding the release.

The Mortgage Indenture provides simplified procedures for the release of property which has been released from the lien of a Class A Mortgage, minor properties and property taken by eminent domain.  Also, under the Mortgage Indenture, we can dispose of obsolete property and grant or surrender specified rights without any release or consent by the Mortgage Indenture trustee.

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If we continue to own any property released from the lien of the Mortgage Indenture, the Mortgage Indenture will not become a lien on any improvement, extension, renewal, replacement or substitution of or for any part or parts of such property.  (See Article Eight)

Withdrawal of Cash

Unless an event of default under the Mortgage Indenture has occurred and is continuing and subject to specified limitations, cash held by the Mortgage Indenture trustee may:

·be withdrawn by us:

·to the extent of the cost or fair value to us (whichever is less) of property additions not constituting funded property, after specified deductions and additions, primarily including adjustments to offset retirements (except that the adjustments need not be made if the property additions were acquired or made within the 90-day period preceding the release); or

·in an amount equal to 10/7ths of the aggregate principal amount of mortgage securities that we would be entitled to issue on the basis of retired securities (with the entitlement to the issuance being waived); or

·in an amount equal to 10/7ths of the aggregate principal amount of any outstanding mortgage securities delivered to the Mortgage Indenture trustee, or

·upon our request, be applied to:

·the purchase of mortgage securities (at prices not exceeding 10/7ths of the principal amount of the purchased mortgage securities); or

·the payment (or provision therefor for the satisfaction and discharge of any mortgage securities) at stated maturity of any mortgage securities or the redemption (or similar provision for redemption) of any mortgage securities which are redeemable (with any mortgage securities received by the Mortgage Indenture trustee pursuant to these provisions being canceled by the Mortgage Indenture trustee) (see Section 806);

provided, however, that we may withdraw cash deposited with the Mortgage Indenture trustee as the basis for the authentication and delivery of mortgage securities, as well as cash representing a payment of principal of Class A Bonds, only in an amount equal to the aggregate principal amount of mortgage securities we would be entitled to issue on any basis (with the entitlement to the issuance being waived by operation of the withdrawal), or we may, at our request, apply this cash to the purchase, redemption or payment of mortgage securities at prices not exceeding, in the aggregate, the principal amount of the mortgage securities.  (See Sections 405 and 702)

Consolidation, Merger, Etc.

We may not consolidate with or merge into any other corporation or convey, otherwise transfer or lease the mortgaged property as or substantially as an entirety to any person unless:

·the transaction is on terms as will fully preserve in all material respects the lien and security of the Mortgage Indenture and the rights and powers of the Mortgage Indenture trustee and the holders of the mortgage securities;

·the corporation formed by any consolidation or into which we are merged or the person which acquires by conveyance or other transfer, or which leases, the mortgaged property as, or substantially as, an entirety is a corporation organized and existing under the laws of the United States of America or any state or territory of the United States of America or the District of Columbia, and that corporation assumes our obligations under the Mortgage Indenture; and

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·in the case of a lease, the lease is made expressly subject to termination by us or by the Mortgage Indenture trustee at any time during the continuance of an event of default.

(See Section 1301)

Modification of Mortgage Indenture

Without the consent of any holders of mortgage securities, we and the Mortgage Indenture trustee may enter into one or more supplemental indentures for any of the following purposes:

·to evidence our successor and our successor’s assumption of our covenants in the Mortgage Indenture and in the mortgage securities; or

·to add one or more of our covenants or other provisions for the benefit of all holders of mortgage securities or for the benefit of the holders of the mortgage securities of one or more specified series, or to surrender any right or power conferred upon us by the Mortgage Indenture; or

·to correct or amplify the description of any property at any time subject to the lien of the Mortgage Indenture; or to better assure, convey and confirm to the Mortgage Indenture trustee any property subject or required to be subjected to the lien of the Mortgage Indenture; or to subject to the lien of the Mortgage Indenture additional property (including property of others), to specify any additional permitted liens with respect to the additional property and to modify the provisions in the Mortgage Indenture for dispositions of specified types of property without release in order to specify any additional items with respect to the additional property; or

·to change or eliminate any provision of the Mortgage Indenture or to add any new provision to the Mortgage Indenture, provided that if the change, elimination or addition adversely affects the interests of the holders of the mortgage securities of any series or tranche in any material respect, the change, elimination or addition will become effective with respect to the series or tranche only when no mortgage security of that series or tranche remains outstanding under the Mortgage Indenture; or

·to establish the form or terms of the mortgage securities of any series or tranche as permitted by the Mortgage Indenture; or

·to provide for the authentication and delivery of bearer securities and coupons representing interest, if any, on the bearer securities and for the procedures for the registration, exchange and replacement of bearer securities and for the giving of notice to, and the solicitation of the vote or consent of, the holders, and for any and all other incidental matters; or

·to evidence and provide for the acceptance of appointment by a successor trustee or by a co-trustee or separate trustee; or

·to establish procedures necessary to permit us to use a non-certificated system of registration for all, or any series or tranche of, the mortgage securities; or to change any place or places for payment, registration of transfer or exchange or where notices may be given; or

·to cure any ambiguity, to correct or supplement any provision in the Mortgage Indenture which may be defective or inconsistent with any other provision in the Mortgage Indenture, or to make any other changes to the provisions of the Mortgage Indenture or to add other provisions with respect to matters and questions arising under the Mortgage Indenture, so long as the other changes or additions do not adversely affect the interests of the holders of mortgage securities of any series or tranche in any material respect.

(See Section 1401)

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In addition, if the Trust Indenture Act of 1939, as amended, is amended after the date of the original Mortgage Indenture in such a way as to require changes to the Mortgage Indenture or the incorporation into the Mortgage Indenture of additional provisions or so as to permit changes to, or the elimination of, provisions which, at the date of the original Mortgage Indenture or at any subsequent time, were required by the Trust Indenture Act to be contained in the Mortgage Indenture, the Mortgage Indenture will be deemed to have been amended so as to conform to the amendment or to effect the changes or elimination, and we and the Mortgage Indenture trustee may, without the consent of any holders, enter into one or more supplemental indentures to evidence or effect the amendment.  (See Section 1401)

Except as provided above, the consent of the holders of not less than a majority in aggregate principal amount of the mortgage securities of all series then outstanding, considered as one class, is required for the purpose of adding any provisions to, or changing in any manner, or eliminating any of the provisions of, the Mortgage Indenture pursuant to one or more supplemental indentures.  However, if less than all of the series of the mortgage securities outstanding are directly affected by a proposed supplemental indenture, then the consent only of the holders of a majority in aggregate principal amount of the outstanding mortgage securities of all series so directly affected, considered as one class, will be required.  If the mortgage securities of any series have been issued in more than one tranche and if the proposed supplemental indenture directly affects the rights of the holders of one or more, but less than all, of the tranches, then the consent only of the holders of a majority in aggregate principal amount of the outstanding mortgage securities of all tranches so directly affected, considered as one class, will be required.  Notwithstanding the above, no such amendment or modification may:

·change the stated maturity of the principal of, or any installment of principal of or interest on, any mortgage security, or reduce the principal amount of any mortgage security or the rate of interest on any mortgage security (or the amount of any installment of interest on any mortgage security), or change the method of calculating the rate, or reduce any premium payable upon the redemption of any mortgage security, or reduce the amount of the principal of any discount security that would be due and payable upon a declaration of acceleration of maturity, or change the coin or currency (or other property) in which any mortgage security or any premium or the interest on any mortgage security is payable, or impair the right to institute suit for the enforcement of any payment on or after the stated maturity of any mortgage security (or, in the case of redemption, on or after the date fixed for redemption) without, in any such case, the consent of the holder of such mortgage security;

·permit the creation of any lien not otherwise permitted by the Mortgage Indenture ranking prior to the lien of the Mortgage Indenture with respect to all or substantially all of the mortgaged property or terminate the lien of the Mortgage Indenture on all or substantially all of the mortgaged property, or deprive the holders of the benefit of the lien of the Mortgage Indenture, without, in any such case, the consent of the holders of all mortgage securities then outstanding;

·reduce the percentage of the principal amount of the outstanding mortgage securities of any series, or any tranche, needed to consent to any supplemental indenture, any waiver of compliance with any provision of the Mortgage Indenture or of any default under the Mortgage Indenture and its consequences, or reduce the requirements for quorum or voting, without, in any such case, the consent of the holder of each outstanding mortgage security of the series or tranche; or

·modify specified provisions of the Mortgage Indenture relating to supplemental indentures, waivers of specified covenants and waivers of past defaults with respect to the mortgage securities of any series, or any tranche of the mortgage securities, without the consent of the holder of each outstanding mortgage security of the series or tranche.

A supplemental indenture which changes or eliminates any covenant or other provision of the Mortgage Indenture which has expressly been included solely for the benefit of the holders of, or which is to remain in effect only so long as there will be outstanding mortgage securities of one or more specified series, or one or more tranches of the outstanding mortgage securities, or modifies the rights of the holders of mortgage securities of the series or tranches with respect to such covenant or other provision, will be deemed not to affect the rights under the Mortgage Indenture of the holders of the mortgage securities of any other series or tranche.  (See Section 1402)

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Voting of Class A Bonds

The Mortgage Indenture trustee will, as holder of any Class A Bonds issued as the basis for the issuance of the mortgage securities, attend the meetings of bondholders under the related Class A Mortgage, or deliver its proxy in connection with the meetings, for matters for which it is entitled to vote or consent.  So long as no event of default as defined in the Mortgage Indenture has occurred and is continuing, the Mortgage Indenture trustee will, as holder of the Class A Bonds with respect to any amendments or modifications to any Class A Mortgage, vote all Class A Bonds outstanding under the Class A Mortgage then held by it, or consent with respect to the amendments or modifications, proportionately with the vote or consent of holders of all other Class A Bonds outstanding under the Class A Mortgage the holders of which are eligible to vote or consent, except that the Mortgage Indenture trustee will not vote in favor of, or consent to, any amendment or modification of a Class A Mortgage which, if it were an amendment or modification of the Mortgage Indenture, would require the consent of holders of the mortgage securities as described under “Modification of the Mortgage Indenture,” without the prior consent of holders of mortgage securities which would be required for the amendment or modification of the Mortgage Indenture.  (See Section 705)

Waiver

The holders of at least a majority in aggregate principal amount of all mortgage securities of all affected series or tranches, considered as one class, may waive our obligations to comply with specified covenants, including the covenants to maintain our corporate existence and properties, pay taxes and discharge liens, maintain insurance and make the recordings and filings as are necessary to protect the security of the holders and the rights of the Mortgage Indenture trustee and the covenant described above with respect to merger, consolidation or the transfer or lease of the mortgaged property as, or substantially as, an entirety, provided that the waiver occurs before the time that compliance is required. (See Section 609)

Events of Default

Each of the following events will be an event of default under the Mortgage Indenture:

·our failure to pay interest on any mortgage security within 60 days after the same becomes due;

·our failure to pay principal of or premium, if any, on any mortgage security within 3 business days after maturity;

·our failure to perform, or our breach of, any covenant or warranty contained in the Mortgage Indenture (other than a covenant or warranty a default in the performance of which or breach of which is dealt with elsewhere under this caption) for a period of 90 days after we have received a written notice from the Mortgage Indenture trustee or the holders of at least 33% in principal amount of outstanding mortgage securities, or unless the Mortgage Indenture trustee, or the Mortgage Indenture trustee and the holders of a principal amount of mortgage securities not less than the principal amount of mortgage securities the holders of which gave the notice, as the case may be, agree in writing to an extension of the period prior to its expiration.  The Mortgage Indenture trustee, or the Mortgage Indenture trustee and the holders, as the case may be, will be deemed to have agreed to an extension of the period if we have initiated corrective action within the period and we are diligently pursuing such corrective action;

·specified events relating to reorganization, bankruptcy and insolvency or appointment of a receiver or trustee for our property; and

·the occurrence of a matured event of default under any Class A Mortgage (other than any such matured event of default which is of similar kind or character to the event of default described in the third bullet above and which has not resulted in the acceleration of the Class A Bonds outstanding under the Class A Mortgage); provided that the waiver or cure of any such event of default and the rescission and

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annulment of the consequences of a matured event of default will constitute a waiver of the corresponding event of default under the Mortgage Indenture and a rescission and annulment of the consequences of a matured event of default.

(See Section 1001)

Remedies

Acceleration of Maturity.  If an event of default under the Mortgage Indenture occurs and is continuing, then the Mortgage Indenture trustee or the holders of not less than 33% in principal amount of mortgage securities then outstanding may declare the principal amount (or if the mortgage securities are discount securities, the portion of the principal amount of the discount securities as may be provided for  pursuant to the terms of the Mortgage Indenture) of all of the mortgage securities then outstanding, together with premium, if any, and accrued interest, if any, on the mortgage securities to be immediately due and payable.  At any time after the declaration of acceleration of the mortgage securities then outstanding, but before the sale of any of the mortgaged property and before a judgment or decree for payment of money has been obtained by the Mortgage Indenture trustee, the event or events of default giving rise to the declaration of acceleration will, without further act, be deemed to have been waived, and the declaration and its consequences will, without further act, be deemed to have been rescinded and annulled, if:

·we have paid or deposited with the Mortgage Indenture trustee a sum sufficient to pay:

·all overdue interest, if any, on all mortgage securities then outstanding;

·the principal of and premium, if any, on any mortgage securities then outstanding which have become due otherwise than by the declaration of acceleration and interest on such amounts at the rate or rates prescribed in the mortgage securities; and

·all amounts due to the Mortgage Indenture trustee; and

·any other event or events of default under the Mortgage Indenture, other than the non-payment of the principal of the mortgage securities which have become due solely by the declaration of acceleration, has been cured or waived in accordance with the provisions of the Mortgage Indenture.

(See Sections 1002 and 1017)

Possession of Mortgaged Property.  Under certain circumstances and to the extent permitted by law, if an event of default occurs and is continuing, the Mortgage Indenture trustee may take possession of, and hold, operate and manage, the mortgaged property or, with or without entry, sell the mortgaged property.  If the mortgaged property is sold, whether by the Mortgage Indenture trustee or pursuant to judicial proceedings, the principal of the outstanding mortgage securities, if not previously due, will become immediately due, together with premium, if any, and any accrued interest.  (See Sections 1003, 1004 and 1005)

Right to Direct Proceedings.  If an event of default under the Mortgage Indenture occurs and is continuing, the holders of a majority in principal amount of the mortgage securities then outstanding will have the right to direct the time, method and place of conducting any proceedings for any remedy available to the Mortgage Indenture trustee or exercising any trust or power conferred on the Mortgage Indenture trustee, provided that (1) the direction does not conflict with any rule of law or with the Mortgage Indenture, and could not involve the Mortgage Indenture trustee in personal liability in circumstances where indemnity would not, in the Mortgage Indenture trustee’s sole discretion, be adequate and (2) the Mortgage Indenture trustee may take any other action deemed proper by the Mortgage Indenture trustee which is not inconsistent with the direction.  (See Section 1016)

Limitation on Right to Institute Proceedings.  No holder of any mortgage security may institute any proceeding, judicial or otherwise, with respect to the Mortgage Indenture or for the appointment of a receiver or for any other remedy under the Mortgage Indenture unless:

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·the holder has previously given to the Mortgage Indenture trustee written notice of a continuing event of default;

·the holders of not less than a majority in aggregate principal amount of the mortgage securities then outstanding have made written request to the Mortgage Indenture trustee to institute proceedings in respect of the event of default and have offered the Mortgage Indenture trustee reasonable indemnity against costs and liabilities to be incurred in complying with the request; and

·for 60 days after receipt of the notice, the Mortgage Indenture trustee has failed to institute any such proceeding and no direction inconsistent with the request has been given to the Mortgage Indenture trustee during the 60-day period by the holders of a majority in aggregate principal amount of the mortgage securities then outstanding.

Furthermore, no holder may institute any such action if and to the extent that the action would disturb or prejudice the rights of other holders.  (See Section 1011)

No Impairment of Right to Receive Payment.  Notwithstanding that the right of a holder to institute a proceeding with respect to the Mortgage Indenture is subject to specified conditions precedent, each holder of a mortgage security has the right, which is absolute and unconditional, to receive payment of the principal of and premium, if any, and interest, if any, on the mortgage security when due and to institute suit for the enforcement of any such payment, and the rights may not be impaired without the consent of the holder.  (See Section 1012)

Notice of Default.  The Mortgage Indenture trustee must give the holders notice of any default under the Mortgage Indenture to the extent required by the Trust Indenture Act, unless the default has been cured or waived, except that the Mortgage Indenture trustee does not have to give notice of a default of the character described in the third bullet under “Events of Default” until at least 75 days after the occurrence of such an event.  For purposes of the preceding sentence, the term “default” means any event which is, or after notice or lapse of time, or both, would become, an event of default.  (See Section 1102)  The Trust Indenture Act currently permits the Mortgage Indenture trustee to withhold notices of default (except for specified payment defaults) if the Mortgage Indenture trustee in good faith determines the withholding of the notice to be in the interests of the holders.

Indemnification of Trustee.  Before taking specified actions to enforce the lien of the Mortgage Indenture and institute proceedings on the mortgage securities, the Mortgage Indenture trustee may require adequate indemnity from the holders of the mortgage securities against costs, expenses and liabilities to be incurred in connection with the enforcement of the lien.  (See Sections 1011 and 1101)

Additional Remedies.  In addition to every other right and remedy provided in the Mortgage Indenture, the Mortgage Indenture trustee may exercise any right or remedy available to the Mortgage Indenture trustee in its capacity as owner and holder of Class A Bonds which arises as a result of a default or matured event of default under any Class A Mortgage, whether or not an event of default under the Mortgage Indenture has occurred and is continuing.  (See Section 1020)

Remedies Limited by State Law.  The laws of the state or states in which the mortgaged property is located may limit or deny the ability of the Mortgage Indenture trustee or security holders to enforce certain rights and remedies provided in the Mortgage Indenture in accordance with their terms.

Defeasance

Any mortgage security or securities, or any portion of the principal amount of the mortgage security or securities will be deemed to have been paid for purposes of the Mortgage Indenture, and, at our election, our entire indebtedness in respect of the Mortgage Indenture will be deemed to have been satisfied and discharged, if we have irrevocably deposited with the Mortgage Indenture trustee or any paying agent (other than us), in trust:

·money (including funded cash not otherwise applied pursuant to the Mortgage Indenture); or

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·in the case of a deposit made prior to the maturity of the applicable mortgage securities, eligible obligations (generally direct or indirect obligations of the U.S. government), which do not contain provisions permitting the redemption or other prepayment at the option of the issuer, the principal of and the interest on which when due, without any regard to reinvestment of the eligible obligations, will provide moneys which, together with the money, if any, deposited with or held by the Mortgage Indenture trustee or the paying agent; or

·a combination of the first two bullets,

which will be sufficient to pay when due the principal of and premium, if any, and interest, if any, due and to become due on the mortgage security or securities or portions of the mortgage securities or securities.

(See Section 901)

Under current United States federal income tax law, a defeasance described in the preceding paragraph would be treated as a taxable exchange of the mortgage securities defeased for a series of non-recourse debt instruments secured by the assets in the defeasance trust.  As a consequence, a holder might recognize gain or loss equal to the difference between the holder’s cost or other tax basis for the mortgage securities and the value of the new debt instruments deemed to have been received in exchange.  Holders should consult their own tax advisors as to the specific consequences to them of defeasance under the Mortgage Indenture.

Resignation or Removal of the Mortgage Indenture Trustee

The Mortgage Indenture trustee may resign at any time by giving written notice of resignation to us.  The Mortgage Indenture trustee may be removed at any time by act of the holders of a majority in principal amount of mortgage securities then outstanding delivered to the Mortgage Indenture trustee and us.  No resignation or removal of the Mortgage Indenture trustee and no appointment of a successor Mortgage Indenture trustee will become effective until a successor Mortgage Indenture trustee has accepted its appointment in accordance with the requirements of the Mortgage Indenture.  So long as no event of default or event which, after notice or lapse of time, or both, would become an event of default has occurred and is continuing, if we have delivered to the Mortgage Indenture trustee a resolution of our Board of Directors appointing a successor Mortgage Indenture trustee and the successor has accepted the appointment in accordance with the terms of the Mortgage Indenture, the Mortgage Indenture trustee will be deemed to have resigned and the successor will be deemed to have been appointed as Mortgage Indenture trustee in accordance with the Mortgage Indenture.  (See Section 1110)

Evidence to be Furnished to the Mortgage Indenture Trustee

When we are required to document our compliance with Mortgage Indenture provisions, we will provide the Mortgage Indenture trustee with written statements of our officers or other persons that we select or pay.  In some cases, we will be required to furnish opinions of counsel and certification of an engineer, accountant, appraiser or other expert (who in some cases must be independent).  In addition, the Mortgage Indenture requires that we give the Mortgage Indenture trustee, at least annually, a brief statement as to our compliance with the conditions and covenants under the Mortgage Indenture.

Concerning the Mortgage Indenture Trustee

We and our affiliates conduct banking transactions with affiliates of the Mortgage Indenture trustee in the normal course of our business and may use the Mortgage Indenture trustee or its affiliates as trustee for various debt issues.

Governing Law

The Mortgage Indenture is governed by and construed in accordance with the laws of the State of New York, except to the extent the Trust Indenture Act is applicable and except to the extent the law of any jurisdiction

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where property subject to the Mortgage Indenture is located mandatorily governs the perfection, priority or enforcement of the lien of the Mortgage Indenture with respect to that property.

DESCRIPTION OF THE SENIOR DEBT SECURITIES

General

We may issue from time to time, in one or more series, the senior debt securities under an Indenture, dated as of July 1, 1999, between us and The Bank of New York Trust Company, N.A., as trustee.  In this “Description of the Senior Debt Securities” we refer to this Indenture, as supplemented and to be supplemented by various supplemental indentures, including one or more supplemental indentures relating to the senior debt securities being offered by this prospectus, as the Indenture.  This prospectus describes the general terms of the senior debt securities that we may offer.  The information we are providing you in this prospectus concerning the senior debt securities and the Indenture is only a summary of the information provided in these documents.  You should consult the senior debt securities themselves, the Indenture and other documents for more complete information on the senior debt securities.  The Indenture is an exhibit to the registration statement, and you should read it for provisions that may be important to you.  In the summary below, we have included references to section numbers of the Indenture so that you can easily locate those provisions.  Capitalized terms used in the following summary have the meanings specified in the Indenture unless otherwise defined below.  When we offer to sell a particular series of senior debt securities, we will describe the specific terms of that series in a prospectus supplement relating to that series.

There is no requirement under the Indenture described in this prospectus that future issues of our debt securities be issued under the Indenture we have described.  We may use other indentures or documentation, which may contain provisions different from those included in the Indenture, in connection with future issues of our debt securities under different registration statements.  The Indenture does not contain any debt covenants or provisions that would afford holders of the senior debt securities protection in the event of a highly leveraged transaction.

The senior debt securities will be our unsecured obligations.  The Indenture does not limit the aggregate principal amount of senior debt securities that we may issue under the Indenture and does not limit the incurrence or issuance of other secured or unsecured debt by us.  As of January 31, 2007, there were $200 million aggregate principal amount of senior debt securities outstanding under the Indenture.  (See Section 301 of the Indenture)  As of January 31, 2007, there were $1.703 billion in aggregate principal amount of our first mortgage bonds outstanding under our Mortgage Indenture.  The Mortgage Indenture constitutes, subject to specified exceptions, a first mortgage lien on substantially all of our properties used or to be used in or in connection with the business of generating, purchasing, transmitting, distributing and/or selling electric energy (See “Description of the First Mortgage Bonds”).

The senior debt securities will rank as equal in right of payment to our other unsecured indebtedness, except for any indebtedness that, by its terms, is subordinate to the senior debt securities.

Please read the prospectus supplement relating to the issue of a particular series of senior debt securities for, among other things, the following terms:

·the title of the series;

·any limit on the aggregate principal amount of the series;

·whether any of the senior debt securities of that series will be issued in global form and, if so, the identity of the depository and the specific terms of the depository arrangements;

·the date or dates on which the principal is payable;

·the rate or rates at which the senior debt securities of that series will bear interest or the method of determining the rate or rates;

·the date or dates from which interest will accrue;

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·the dates on which the interest will be payable and the regular record dates for the interest payment dates;

·the place or places where the principal of, premium, if any, and interest will be payable;

·any redemption terms, including mandatory redemption through a sinking fund or otherwise, redemption at our option and redemption at the option of the holder;

·the denominations in which the senior debt securities will be issuable, if other than denominations of $1,000 and any integral multiple $1,000;

·whether the provisions of the Indenture relating to defeasance and covenant defeasance will be applicable to the senior debt securities of that series, provided that the provisions will apply unless the covenants are expressly stated to be inapplicable to the senior debt securities of that series; and

·any other terms of the senior debt securities of that series.

(See Section 301 of the Indenture)

Periodic Offering

We may offer senior debt securities of any series in a periodic offering, in which any or all of the specific terms of each security of the series may vary from other securities of the series, including with respect to rate or rates of interest on the securities, if any, the stated maturity of each security, the redemption provisions, if any, and such other terms as may be permitted by the Indenture and determined by us from time to time as provided in the Indenture and described in the applicable prospectus supplement.

Discount Security

A senior debt security may provide that an amount less than the principal amount of the senior debt security would be due and payable if it were to be accelerated because of an event of default.  Senior debt securities containing such a provision would be offered and sold at a substantial discount below their principal amount.  Special federal income tax, accounting and other considerations relating to those securities will be described in the applicable prospectus supplement.

Payment of Senior Debt Securities; Transfers; Exchanges

Unless the prospectus supplement that describes a particular series of senior debt securities says otherwise with respect to that series, we will pay interest, if any, on each senior debt security payable on each interest payment date to the person in whose name the senior debt security is registered as of the close of business on the regular record date relating to that interest payment date.  We will pay interest payable at maturity to the person to whom principal is paid at maturity.  If there has been a default in the payment of interest on any senior debt security, the defaulted interest may be paid to the holder of the senior debt security as of the close of business on a date selected by the senior debt security trustee.  The date selected must not be more than 15 days and not less than 10 days prior to the date we propose for payment of the defaulted interest.  Defaulted interest may also be paid in any other lawful manner permitted by requirements of any securities exchange on which the senior debt security may be listed, if the Indenture trustee deems the manner of payment practicable.  (See Section 307 of the Indenture)

Unless the prospectus supplement that describes a particular series of senior debt securities says otherwise with respect to that series, the principal of and premium, if any, and interest at maturity will be payable upon presentation of the senior debt securities at the corporate trust office of The Bank of New York Trust Company, N.A., in New York, New York, as our Paying Agent.  We may change the place of payment.  We may appoint one or more additional paying agents and may remove any paying agent, all at our discretion.  (See Section 1002 of the Indenture)

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Unless the prospectus supplement that describes a particular series of senior debt securities says otherwise with respect to that series, the transfer of senior debt securities may be registered, and senior debt securities may be exchanged for other senior debt securities of the same series and tranche, of authorized denominations and of like tenor and aggregate principal amount, at the corporate trust office of The Bank of New York Trust Company, N.A., in New York, New York, as security registrar.  We may change the place for registration of transfer and exchange.  We may designate one or more additional places for the registration and exchange, all at our discretion.  (See Sections 305 and 1002 of the Indenture)

Unless the prospectus supplement that describes a particular series of senior debt securities says otherwise with respect to that series, no fee for service will be charged for any transfer or exchange of the senior debt securities, but we may require payment of a sum sufficient to cover any tax or other governmental charge imposed in connection with any registration of, transfer or exchange of the securities.  We are not required to execute or to provide for the registration of transfer of or the exchange of (1) any senior debt security during a period of 15 days prior to giving any notice of redemption or (2) any senior debt security selected for redemption in whole or in part, except the unredeemed portion of any senior debt security being redeemed in part.  (See Section 305 of the Indenture)

Redemption

The prospectus supplement that describes that series will set forth any terms for the optional or mandatory redemption of a particular series of senior debt securities.  Unless the prospectus supplement says that senior debt securities are redeemable at the option of a holder, senior debt securities that are redeemable will be redeemable only at our option upon notice by mail at least 30 days prior to the date fixed for redemption.  If fewer than all the senior debt securities of a series are to be redeemed, the particular senior debt securities to be redeemed will be selected by the trustee by the method provided for that series or, if no method is provided, substantially pro rata, by lot or by any other method as the trustee considers fair and appropriate and which complies with the requirement of the principal national securities exchange, if any, on which the senior debt securities are listed.  If senior debt securities of a series or tranche have different terms and different maturities, we may select the particular senior debt securities to be redeemed.  (See Sections 1103 and 1104 of the Indenture)

If redemption is at our option, the notice of redemption may state that the redemption will be conditional upon receipt by the paying agent or agents, on or prior to the date fixed for the redemption, of money sufficient to redeem all of the senior debt securities called for redemption, including accrued interest, if any.  If no money has been received, the notice will not be effective and we will not be required to redeem the senior debt securities.  (See Section 1104 of the Indenture)

Consolidation, Merger or Sale

The Indenture provides that we will not consolidate with, merge with or into any other corporation, whether or not we are the surviving corporation, or sell, assign, transfer or lease all or substantially all of our properties and assets as an entirety or substantially as an entirety to any person or group of affiliated persons, in one transaction or a series of related transactions, unless:

·either we are the continuing person or the person, if other than us, formed by the consolidation or with which or into which we are merged or the person, or group of affiliated persons, to which all or substantially all of our properties and assets as an entirety or substantially as an entirety are sold, assigned, transferred or leased is a corporation, or constitute corporations, organized under the laws of the United States or any State of the United States or the District of Columbia and expressly assumes, by an indenture supplemental to the Indenture, executed and delivered to the Indenture trustee in a form satisfactory to the Indenture trustee, all of our obligations under the senior debt securities issued under the Indenture and all of our obligations under the Indenture;

·immediately before and after giving effect to the transaction or series of transactions, no event of default, and no default, has occurred and is continuing; and

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·we deliver to the Indenture trustee an officer’s certificate and an opinion of counsel stating that the consolidation, merger or transfer and the supplemental indenture comply with the Indenture.  (See Article Eight of the Indenture)

Events of Default

The following are events of default under the Indenture with respect to senior debt securities of any series issued under the Indenture:

·our failure to pay interest on any senior debt security of that series when due and the failure continues for 30 days and the time for payment has not been extended or deferred;

·our failure to pay the principal of, or premium, if any, on, any senior debt security of that series when due and payable at maturity, and upon redemption but excluding any failure by us to deposit money in connection with any redemption at our option, and the time for payment has not been extended or deferred;

·our failure to observe or perform any other covenant, warranty or agreement contained in the senior debt securities of that series or in the Indenture, other than a covenant, agreement or warranty included in the Indenture solely for the benefit of senior debt securities other than that series, and the failure continues for 60 days after we have received written notice from the Indenture trustee or holders of at least 25% in aggregate principal amount of the outstanding senior debt securities of that series;

·specified events of bankruptcy, insolvency or reorganization relating to us;

·our failure to pay any installment of interest when due on any other series of senior debt securities issued pursuant to the Indenture and the failure continues for 30 days, or our failure to pay the principal of, or premium, if any, on any such other series of senior debt securities when due and payable at maturity, including upon redemption but excluding any failure by us to deposit money in connection with any redemption at our option, and the time for payment of that interest or principal (or premium, if any) has not been extended or deferred; and

·any other event of default with respect to senior debt securities of that series specified in the applicable prospectus supplement.

(See Section 501 of the Indenture)

Remedies

Acceleration of Maturity.  If an event of default with respect to senior debt securities of any series, other than due to events of bankruptcy, insolvency or reorganization, occurs and is continuing, the Indenture trustee or the holders of at least 25% in aggregate principal amount of the outstanding senior debt securities of that series, by notice in writing to us, and to the Indenture trustee if given by the holders of at least 25% in aggregate principal amount of the senior debt securities of that series, may declare the unpaid principal of and accrued interest to the date of acceleration, or, if the senior debt securities are Original Issue Discount Securities, the portion of that principal as may be specified in the terms of the Indenture, on all the outstanding senior debt securities of that series to be due and payable immediately and, upon any such declaration, the senior debt securities of that series, or specified principal amount, will become immediately due and payable.  (See Section 502 of the Indenture)

If an event of default occurs due to bankruptcy, insolvency or reorganization, all unpaid principal of and accrued interest on the outstanding senior debt securities of all series will become immediately due and payable without any declaration or other act on the part of the Indenture trustee or any holder of any senior debt security.  (See Section 502 of the Indenture)

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The holders of a majority of the principal amount of the outstanding senior debt securities of that series, upon the conditions provided in the Indenture, may rescind an acceleration and its consequences.  (See Section 502 of the Indenture)

Right to Direct Proceedings.  The holders of a majority in principal amount of the outstanding senior debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the Indenture trustee, or exercising any trust or power conferred on the Indenture trustee, with respect to the senior debt securities of that series; provided that (1) the direction is not in conflict with any law or the Indenture; (2) the Indenture trustee may take any other action deemed proper by the Indenture trustee which is not inconsistent with the direction; and (3) subject to its duties under the Trust Indenture Act, the Indenture trustee need not take any action that might involve the Indenture trustee in personal liability or might be unduly prejudicial to the holders not joining in the action.  (See Section 512 of the Indenture)

Limitation on Rights to Institute Proceedings.  No holder of the senior debt securities of any series will have any right to institute any proceeding with respect to the Indenture, or for the appointment of a receiver or a trustee, or for any other remedy under the Indenture, unless:

·the holder has previously given to the Indenture trustee written notice of a continuing event of default with respect to the senior debt securities of that series;

·the holders of at least 25% in aggregate principal amount of the outstanding senior debt securities of that series have made written request to the Indenture trustee, and the holder or holders have offered to the Indenture trustee reasonable indemnity, to institute the proceeding as trustee; and

·the Indenture trustee has failed to institute the proceeding, and has not received from the holders of a majority in aggregate principal amount of the outstanding senior debt securities of that series a direction inconsistent with the request, within 60 days after the notice, request and offer.

(See Section 507 of the Indenture)

No Impairment of Right to Receive Payment.  Notwithstanding any other provision of the Indenture, the holder of any senior debt security will have the absolute and unconditional right to receive payment of the principal of (and premium, if any) and interest on that senior debt security when due, and to institute suit for enforcement of that payment.  This right may not be impaired without the consent of the holder.  (See Section 508 of the Indenture)

Notice of Default.  The Indenture provides that the Indenture trustee must, within 30 days after the occurrence of any default or event of default with respect to senior debt securities of any series issued under the Indenture, give the holders of senior debt securities of that series notice of all uncured defaults or events of default known to it (the term “default” includes any event which after notice or passage of time or both would be an event of default); provided, however, that, except in the case of an event of default or a default in payment on any senior debt securities of any series, the Indenture trustee will be protected in withholding the notice if and so long as the board of directors, the executive committee or directors or responsible officers of the Indenture trustee in good faith determine that the withholding of the notice is in the interest of the holders of senior debt securities of the affected series.  (See Section 602 of the Indenture)

Indemnification of Trustee.  Subject to the provisions of the Indenture relating to the duties of the Indenture trustee if an event of default occurs and is continuing, the Indenture trustee will be under no obligation to exercise any of its rights or powers under the Indenture at the request or direction of any of the holders, unless the holders have offered to the Indenture trustee reasonable indemnity.  (See Section 603 of the Indenture)

Waiver.  The holders of not less than a majority in aggregate principal amount of the outstanding senior debt securities of any series may on behalf of the holders of all senior debt securities of that series waive any default or event of default with respect to that series, except a default or event of default in the payment of the principal of, or premium, if any, or any interest, if any, on any senior debt securities of that series or in respect of a provision

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which under the Indenture cannot be modified or amended without the consent of the holder of each outstanding senior debt securities of that series affected.  (See Section 513 of the Indenture)

Modification of Indenture

We and the Indenture trustee may modify the Indenture, without notice to or the consent of any holders of senior debt securities, with respect to specified matters, including:

·to add one or more covenants or other provisions for the benefit of holders of senior debt securities of one or more series or to surrender any of our rights or powers under the Indenture;

·to cure any ambiguity, defect or inconsistency or to correct or supplement any provision which may be inconsistent with any other provision of the Indenture; or

·to make any change that does not materially adversely affect the interests of any holder of senior debt securities of any series.

If the Trust Indenture Act is amended after the date of the original Indenture in such a way as to require or permit changes to the Indenture, or the elimination of provisions which, at the date of the original Indenture or at any time subsequently were required by the Trust Indenture Act, the Indenture will be automatically amended to conform to the amendment or to make the changes or elimination.  The Indenture trustee will, at our request, enter into one or more supplemental indentures with us to evidence or effect the amendment.  (See Section 901 of the Indenture)

In addition, we, together with the Indenture trustee, may modify some of our rights and obligations and the rights of holders of the senior debt securities with the consent of the holders of at least a majority in aggregate principal amount of the outstanding senior debt securities of each series affected thereby.

No amendment or modification may, without the consent of each holder of any outstanding senior debt security affected:

·change the stated maturity of the principal of, or any installment of principal of or interest on, any such senior debt security;

·reduce the principal amount of, or the rate of interest on, or any premium payable upon the redemption of, or extend the time for payment of, any such senior debt security, or extend the time for payment of those amounts or reduce the amount of principal of an original issue discount security that would be due and payable upon declaration of acceleration of the maturity of the senior Debt security;

·change the place of payment, or the coin or currency, for payment of principal of, or premium, if any, or interest on any senior debt security;

·impair the right to institute suit for the enforcement of any payment on or with respect to any such senior debt security;

·reduce the percentage in principal amount of outstanding senior debt securities of any series necessary to modify or amend the Indenture, or to waive compliance with specified provisions of the Indenture or defaults or events of default under the Indenture and their consequences;

·change the redemption provisions in a manner adverse to any such holder of senior debt securities of that series; or

·modify any of the foregoing provisions or any of the provisions relating to the waiver of specified past defaults or specified covenants except to increase the percentage of holders required to consent or

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waive or to provide that specified other provisions may not be modified or waived without the consent of each holder affected thereby.

(See Article Nine of the Indenture)

Defeasance

When we use the term defeasance, we mean discharge from some or all of our obligations under the Indenture. If we deposit with the trustee funds or U.S. government obligations the scheduled payments of principal and interest in respect of which is sufficient to make payments of principal of (and premium, if any) and interest on the senior debt securities of a series or tranche thereof on the dates those payments are due and payable, then, at our option, either of the following will occur:

·“covenant defeasance,” which means that we will no longer have any obligation to comply with the restrictive covenants under the Indenture and any other restrictive covenants that apply to that series or tranche of the senior debt securities, and the related events of default will no longer apply to us;.

·“legal defeasance,” which means that we will be discharged from our payment obligations, in addition to the obligations referred to above, with respect to the senior debt securities of that series or tranche;

So long as no default or event of default with respect to the senior debt securities of any series has occurred and is continuing, we may affect either a legal defeasance or a covenant defeasance in respect of senior debt securities of that series or tranche by:

·depositing with the Indenture trustee, under the terms of an irrevocable trust agreement, money or U.S. Government Obligations or a combination sufficient to pay, when due, all remaining indebtedness on the senior debt securities of that series;

·delivering to the Indenture trustee either an opinion of counsel or a ruling directed to the Indenture trustee from the Internal Revenue Service to the effect, among other things, that the holders of the senior debt securities of that series will not recognize income, gain or loss for federal income tax purposes as a result of the deposit and termination of obligations, and

·complying with specified other requirements set forth in the Indenture.  (See Section 1304 of the Indenture)

Evidence to be Furnished to the Indenture Trustee

The Indenture provides that we must periodically file statements with the Indenture trustee regarding our compliance with all conditions and covenants of the Indenture.  (See Section 704 of the Indenture)

Concerning the Indenture Trustee

We and our affiliates conduct banking transactions with the Indenture trustee in the normal course of business.

Governing Law

The Indenture is governed by and construed in accordance with the laws of the State of New York, without regard to conflict of laws principles, except to the extent that the Trust Indenture Act is applicable.

BOOK-ENTRY SYSTEM

Each series of securities offered by this prospectus may be issued in the form of one or more global securities representing all or part of that series of securities.  This means that we will not issue certificates for that

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series of securities to the holders.  Instead, a global security representing that series will be deposited with, or on behalf of, DTC, or its successor as the Depository and registered in the name of the Depository or a nominee of the Depository.

The Depository will keep a computerized record of its participants (for example, your broker) whose clients have purchased debt securities represented by a global security.  Unless it is exchanged in whole or in part for a certificated security, a global security may not be transferred, except that the Depository, its nominees and their successors may transfer a global security as a whole to one another.

Beneficial interests in global securities will be shown on, and transfers of interests will be made only through, records maintained by the Depository and its participants.  The laws of some jurisdictions require that some purchasers take physical delivery of securities in definitive form.  These laws may impair the ability to transfer beneficial interests in a global security.

We will wire principal, interest and any premium payments to the Depository or its nominee.  We and the trustee will treat the Depository or its nominee as the owner of the global security for all purposes, including any notices and voting.  Accordingly, we, the applicable trustee and any paying agent will have no direct responsibility or liability to pay amounts due on a global security to owners of beneficial interests in a global security.

Unless we specify otherwise in the prospectus supplement that describes a particular series of first mortgage bonds or senior debt securities, DTC will act as Depository for securities issued as global securities.  The securities will be registered in the name of Cede & Co. (DTC’s partnership nominee) or such other name as may be requested by an authorized representative of DTC.

DTC is a limited-purpose trust company organized under the New York Banking Law, a “banking organization” within the meaning of the New York Banking Law, a member of the Federal Reserve System, a “clearing corporation” within the meaning of the New York Uniform Commercial Code, and a “clearing agency” registered pursuant to the provisions of Section 17A of the Securities Exchange Act of 1934.  DTC holds securities that its participants (“Direct Participants”) deposit with DTC.  DTC also facilitates the post-trade settlement among Direct Participants of sales and other securities transactions in deposited securities through electronic computerized book-entry transfers and pledges between Direct Participants’ accounts.  This eliminates the need for physical movement of securities certificates.  Direct Participants include both U.S. and non-U.S. securities brokers and dealers, banks, trust companies, clearing corporations, and certain other organizations.  DTC is a wholly-owned subsidiary of The Depository Trust & Clearing Corporation (“DTCC”).  DTCC, in turn, is owned by a number of Direct Participants of DTC and Members of the National Securities Clearing Corporation, Government Securities Clearing Corporation, MBS Clearing Corporation and Emerging Markets Clearing Corporation (NSCC, GSCC, MBSCC and EMCC, also subsidiaries of DTCC), as well as by the New York Stock Exchange, Inc., the American Stock Exchange LLC and the National Association of Securities Dealers, Inc.  Access to the DTC system is also available to others such as both U.S. and non-U.S. securities brokers and dealers, banks, trust companies, and clearing corporations that clear through or maintain a custodial relationship with a Direct Participant, either directly or indirectly (“Indirect Participants”).  The DTC Rules applicable to its Participants are on file with the SEC.  More information about DTC can be found at www.dtcc.com and www.dtc.org.

Purchases of global securities under the DTC system must be made by or through Direct Participants, which will receive a credit for the global securities on DTC’s records.  The ownership interest of each actual purchaser of each global security (“Beneficial Owner”) is in turn to be recorded on the Direct and Indirect Participants’ records.  Beneficial Owners will not receive written confirmation from DTC of their purchase.  Beneficial Owners are, however, expected to receive written confirmations providing details of the transaction, as well as periodic statements of their holdings, from the Direct or Indirect Participant through which the Beneficial Owner entered into the transaction.  Transfers of ownership interests in the global securities are to be accomplished by entries made on the books of Direct and Indirect Participants acting on behalf of Beneficial Owners.  Beneficial Owners will not receive certificates representing their ownership interests in global securities, except in the event that use of the book-entry system for the global securities is discontinued.

To facilitate subsequent transfers, all securities deposited by Direct Participants with DTC are registered in the name of DTC’s partnership nominee, Cede & Co. or such other name as may be requested by an authorized

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representative of DTC.  The deposit of securities with DTC and their registration in the name of Cede & Co. or such other nominee do not effect any change in beneficial ownership.  DTC has no knowledge of the actual Beneficial Owners of the securities;  DTC’s records reflect only the identity of the Direct Participants to whose accounts such securities are credited, which may or may not be the Beneficial Owners.  The Direct and Indirect Participants will remain responsible for keeping account of their holdings on behalf of their customers.

Conveyance of notices and other communications by DTC to Direct Participants, by Direct Participants to Indirect Participants, and by Direct Participants and Indirect Participants to Beneficial Owners will be governed by arrangements among them, subject to any statutory or regulatory requirements as may be in effect from time to time.

Redemption notices shall be sent to DTC.  If less than all of the global securities of a series are being redeemed, DTC’s practice is to determine by lot the amount of the interest of each Direct Participant in such series to be redeemed.

Neither DTC nor Cede & Co. (nor such other DTC nominee) will consent or vote with respect to the global securities unless authorized by a Direct Participant in accordance with DTC’s procedures.  Under its usual procedures, DTC mails an omnibus proxy to us as soon as possible after the record date.  The omnibus proxy assigns Cede & Co.’s consenting or voting rights to those Direct Participants to whose accounts the global securities are credited on the record date (identified in a listing attached to the omnibus proxy).

Redemption proceeds and distributions on the global securities will be made to Cede & Co., or such other nominee as may be requested by an authorized representative of DTC.  DTC’s practice is to credit Direct Participants’ accounts, upon DTC’s receipt of funds and corresponding detail information from us or the trustee on payable date in accordance with their respective holdings shown on DTC’s records.  Payments by Participants to Beneficial Owners will be governed by standing instructions and customary practices, as is the case with securities held for the accounts of customers in bearer form or registered in “street name,” and will be the responsibility of such Participant and not of DTC nor its nominee, the trustee, or us, subject to any statutory or regulatory requirements as may be in effect from time to time.  Payment of redemption proceeds and distributions to Cede & Co. (or such other nominee as may be requested by an authorized representative of DTC ) is the responsibility of us or the trustee, disbursement of such payments to Direct Participants will be the responsibility of DTC, and disbursement of such payments to the Beneficial Owners will be the responsibility of Direct and Indirect Participants.

DTC may discontinue providing its services as securities depository with respect to the global securities at any time by giving reasonable notice to us or the trustee.  Under such circumstances, in the event that a successor securities depository is not obtained, securities certificates are required to be printed and delivered.

We may decide to discontinue use of the system of book-entry-only transfers through DTC (or a successor securities depository).  In that event, security certificates will be printed and delivered to DTC.

The information in this section concerning DTC and DTC’s book entry system has been obtained from DTC, and we and any underwriters, dealers or agents are not responsible for the performance by DTC of its obligations under the rules and procedures governing its operations or otherwise.

Any underwriters, dealers or agents of any securities may be Direct Participants of DTC.

PLAN OF DISTRIBUTION

We intend to sell the securities offered by this prospectus to or through underwriters or dealers, and may also sell the securities directly to other purchasers or through agents, as described in the prospectus supplement relating to an issue of securities.

The distribution of the securities described in this prospectus may be effected from time to time in one or more transactions at a fixed price or prices, which may be changed, at market prices prevailing at the time of sale, at prices related to the prevailing market prices, or at negotiated prices.

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In connection with the sale of the securities, underwriters may receive compensation from us or from purchasers of the securities for whom they may act as agents in the form of discounts, concessions, or commissions.  Underwriters may sell the securities to or through dealers, and the dealers may receive compensation in the form of discounts, concessions, or commissions from the underwriters and/or commissions from the purchasers for whom they may act as agents.  Underwriters, dealers, and agents that participate in the distribution of the securities may be deemed to be underwriters, and any discounts or commissions received by them from us and any profit on the resale of the securities by them may be deemed to be underwriting discounts and commissions under the Securities Act of 1933, as amended.  Any person who may be deemed to be an underwriter will be identified, and any compensation received from us will be described in the prospectus supplement.

Under agreements which we may enter in connection with the sale of the securities, underwriters, dealers, and agents who participate in the distribution of the securities may be entitled to indemnification by us against specified liabilities, including liabilities under the Securities Act of 1933, as amended.

No person has been authorized to give any information or to make any representation not contained in this prospectus and, if given or made, that information or representation must not be relied upon as having been authorized.  This prospectus does not constitute an offer to sell or a solicitation of an offer to buy any of the securities offered by this prospectus in any jurisdiction to any person to whom it is unlawful to make the offer in the jurisdiction.  Neither the delivery of this prospectus nor any sale made under this prospectus shall, under any circumstances, create any implication that the information in this prospectus is correct as of any time subsequent to the date of this prospectus or that there has been no change in our affairs since that date.

LEGAL OPINIONS

Legal opinions relating to the securities being offered by this prospectus and certain other matters will be rendered by LeBoeuf, Lamb, Greene & MacRae LLP, New York, New York, counsel for the company, Ryley Carlock & Applewhite, Denver, Colorado, counsel for the company, and Jones Day, Chicago, Illinois, counsel for the company.  The validity of the securities and certain other matters will be passed upon for the underwriters, dealers or agents named in a prospectus supplement by Dewey Ballantine LLP, New York, New York.  In giving their opinion, Dewey Ballantine LLP may rely on the opinion of LeBoeuf, Lamb, Greene & MacRae LLP as to matters of Colorado law.

EXPERTS

The consolidated financial statements and the related consolidated financial statement schedule incorporated in this prospectus by reference from the company’s Annual Report on Form 10-K for the year ended December 31, 2006 have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their report, (which report expresses an unqualified opinion and includes an explanatory paragraph relating to the adoption of Statement of Financial Accounting Standards No. 158, “Employers’ Accounting for Defined Benefit Pension and Other Postretirement Plans”) which is incorporated herein by reference, and has been so incorporated in reliance upon the report of such firm given upon their authority as experts in accounting and auditing.

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14.Other Expenses of Issuance and Distribution.

Securities and Exchange Commission Registration Fee	$	29,933	*
Blue Sky Fees	30,000
Accountants’ Fees and Expenses	180,000
Counsel’s Fees and Expenses	510,000
Trustees’ Fees and Expenses, including Counsel and Authentication Fees	54,000
Printing of Registration Statement, Prospectus, Prospectus Supplements, Supplemental Indentures, etc.	60,000
Rating Agencies’ Fees	981,000
Miscellaneous	55,067
Total Expenses	$	1,900,000

*All items are estimated except the first.

Item 15.Indemnification of Directors and Officers.

Sections 7-108-402, 7-109-102, 7-109-103, 7-109-104, 7-109-105, 7-109-106, 7-109-107, 7-109-108, 7-109-109 and 7-109-110 of the Colorado Business Corporation Act provide for indemnification of directors, officers, employees, fiduciaries and agents of Colorado corporations such as the Registrant, subject to certain limitations, and authorize such corporations to purchase and maintain insurance on behalf of such persons against any liability incurred in any such capacity or arising out of their status as such.  The registrant currently has such insurance in effect.

A resolution adopted at a special meeting of stockholders of the registrant held in November, 1943, provides:  “That each Director and Officer of the Company (or his legal representative) shall be indemnified by the Company against all claims, liabilities, expenses and costs imposed upon or reasonably incurred by him in connection with any action, suit or proceeding, or the settlement or compromise of any such claim, liability, action, suit or proceeding (other than amounts paid to the Company itself), in which he may be involved by reason of his being or having been such Director or Officer of the Company, except in relation to matters as to which he shall be finally adjudged in any such action, suit or proceeding to have been derelict in the performance of his duties as such Director or Officer, provided, however, in respect to any such settlement or compromise that it shall have been determined, by a majority of the Directors of the Company not affected by self interest, that such settlement or compromise should be made, and that such Director or Officer had not been derelict in the performance of his official duties; and provided further that the foregoing indemnity shall not extend to or cover any claims, liabilities, action, suit or proceeding under the Securities Act or any costs or expenses in connection therewith unless the Director or Officer of the Company involved shall be finally adjudged in such action, suit or proceeding to have been subject to no liability under said Act, or in case of settlement or compromise, unless the Company shall have obtained an opinion of independent counsel to the effect that he is not liable under said Act.  The foregoing right of indemnification shall not be exclusive of any other right or rights to which such Director or Officer may be entitled as a matter of law.”

Paragraph 7 of the registrant’s Restated Articles of Incorporation, as amended, provides:  “A director of the Corporation shall not be personally liable to the Corporation or its shareholders for monetary damages for breach of fiduciary duty as a director, except for liability (a) for any breach of the director’s duty of loyalty to the Corporation or to its shareholders, (b) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (c) for a breach of Colorado Revised Statutes Section 7-108-403, or (d) for any transaction from which the director directly or indirectly derived an improper personal benefit.”

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To the maximum extent permitted by law, we will indemnify any person who is or was our director, officer, agent, fiduciary or employee against any claim, liability, loss or expense arising against or incurred by such person as a result of circumstances, events, actions and omissions occurring in such capacity.  We further will have the authority to maintain insurance at our expense providing for such indemnification, including insurance with respect to claims, liabilities, losses and expenses against which we would not otherwise have the power to indemnify such persons.

Item 16.Exhibits.

1(a)	Form of Underwriting Agreement with respect to the first mortgage bonds.
1(b)	Form of Underwriting Agreement with respect to the senior debt securities.
2*	Agreement and Plan of Merger, dated as of March 24, 1999, by and between Northern States Power Company and New Century Energies, Inc. (Exhibit 2.1 to the Report on Form 8-K (File No. 1-12907) of New Century Energies, Inc. dated March 24, 1999).
4(a)(1)*	Indenture, dated as of October 1, 1993, providing for the issuance of first mortgage bonds (Exhibit 4(a) to the Company’s Form 10-Q for the quarter ended September 30, 1993).
4(a)(2)*	Indentures supplemental to the Indenture referenced in Exhibit 4(a)(1) above:

Dated as of	Previous Filing: Form; Date or File No.	Exhibit No.
November 1, 1993	S-3, (33-51167)	4(b)(2)
January 1, 1994	10-K, 1993	4(b)(3)
September 2, 1994	8-K, Sept. 1994	4(b)
May 1, 1996	10-Q, June 30, 1996	4(b)
November 1, 1996	10-K, 1996	4(b)(3)
February 1, 1997	10-Q, March 31, 1997	4(b)
April 1, 1998	10-Q, March 31, 1998	4(b)
August 15, 2002	10-Q, Sept. 30, 2002	4.01
September 1, 2002	8-K, Sept. 18, 2002	4.01
September 15, 2002	10-Q, Sept. 30, 2002	4.02
March 1, 2003	S-3, April 14, 2003 (333-104504)	4(b)(3)
April 1, 2003	Xcel 10-Q May 15, 2003 (001-03034)	4.02
May 1, 2003	S-4, June 11, 2003 (333-106011)	4.9
September 1, 2003	8-K, Sept. 2, 2003 (001-03280)	4.02
September 15, 2003	Xcel 10-K, Mar. 15, 2004 (001-03034)	4.100
August 1, 2005	8-K, Aug. 18, 2005 (001-03280)	4.02

4(a)(3)	Form of Supplemental Indenture establishing a series of first mortgage bonds under the Indenture referenced in Exhibit 4(a)(1) above.
4(a)(4)	Form of First Mortgage Bonds (included in the Form of Supplemental Indenture referenced in Exhibit 4(a)(3) above).
4(b)(1)*	Indenture, dated July 1, 1999, providing for the issuance of senior debt securities (Exhibit 4.01 to Form 8-K dated July 13, 1999).
4(b)(2)*	Indentures supplemental to the Indenture referenced in Exhibit 4(b)(1) above:

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Dated as of	Previous Filing: Form; Date or File No.	Exhibit No.
July 15, 1999	8-K, July 13, 1999	4.2

4(b)(3)	Form of Supplemental Indenture establishing a series of senior debt securities under the Indenture referenced in Exhibit 4(b)(1) above.
4(b)(4)	Form of Senior Debt Securities (included in the Form of Supplemental Indenture referenced in Exhibit 4(b)(3) above).
5	Opinion of LeBoeuf, Lamb, Greene & MacRae LLP regarding the validity of securities.
12	Statement Regarding Computation of Ratio of Consolidated Earnings to Consolidated Fixed Charges.
23(a)	Consent of LeBoeuf, Lamb, Greene & MacRae LLP is included in its opinion referenced in Exhibit 5 above.
23(b)	Consent of Ryley Carlock & Applewhite
23(c)	Consent of Deloitte & Touche LLP
24	Power of Attorney
25(a)	Form T-1 Statement of Eligibility of U.S. Bank Trust National Association (formerly First Trust of New York, National Association), as Successor Trustee under the Indenture relating to first mortgage bonds referenced in Exhibit 4(a)(1) above.
25(b)	Form T-1 Statement of Eligibility of The Bank of New York Trust Company, N.A., as Trustee under the Indenture relating to senior debt securities referenced in Exhibit 4(b)(1) above.

*Previously filed as indicated and incorporated herein by reference.

Item 17.Undertakings.

The undersigned registrant hereby undertakes:

(1)To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement: (i) to include any prospectus required by section 10(a)(3) of the Securities Act of 1933; (ii) to reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement.  Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represented no more than a 20% change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement; and (iii) to include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement; provided, however, that (A) clauses (i) and (ii) above do not apply if the registration statement is on Form S-8, and the information required to be included in a post-effective amendment by those clauses is contained in reports filed with or furnished to the SEC by the registrant pursuant to section 13 or section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement; and (B) Clauses (i), (ii) and (iii) above do not apply if the registration statement is on Form S-3 or Form F-3 and the information required to be included in a post-effective amendment by those paragraphs

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is contained in reports filed with or furnished to the Commission by the registrant pursuant to section 13 or section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

(2)That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3)To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(4)That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

(i)If the registrant is relying on Rule 430B:

(A)Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

(B)Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus.  As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.  Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date; or

(ii)If the registrant is subject to Rule 430C, each prospectus filed pursuant to Rule 424(b) as part of a registration statement relating to an offering, other than registration statements relying on Rule 430B or other than prospectuses filed in reliance on Rule 430A, shall be deemed to be part of and included in the registration statement as of the date it is first used after effectiveness.  Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such first use, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such date of first use.

(5)That, for the purpose of determining liability of the registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities:

The undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such

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purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i)Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;

(ii)Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;

(iii)The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

(iv)Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.

The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant’s annual report pursuant to section 13(a) or section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions described under Item 15, or otherwise, the registrant has been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable.  In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue.

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SIGNATURES

Pursuant to the requirements of the Securities Act, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City and County of Denver and the State of Colorado, on the 19th day of March, 2007.

PUBLIC SERVICE COMPANY OF COLORADO
By:	/s/ Richard C. Kelly

Pursuant to the requirements of the Securities Act, this registration statement has been signed below by the following persons in the capacities and on the date indicated:

Signature	Title	Date
*	President, Chief Executive Officer	March 19, 2007
Patricia K. Vincent	and Director
	(Principal Executive Officer)
*	Vice President, Chief Financial	March 19, 2007
Benjamin G.S. Fowke III	Officer and Director
	(Principal Financial Officer)
*	Vice President and Controller	March 19, 2007
Teresa S. Madden	(Principal Accounting Officer)
*	Director	March 19, 2007
Richard C. Kelly
*	Director	March 19, 2007
Gary R. Johnson
*	Director	March 19, 2007
Paul J. Bonavia

* By:	/s/ Richard C. Kelly
	(Attorney-in-Fact)
	March 19, 2007

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EXHIBIT INDEX

1(a)	Form of Underwriting Agreement with respect to the first mortgage bonds.
1(b)	Form of Underwriting Agreement with respect to the senior debt securities.
2*	Agreement and Plan of Merger, dated as of March 24, 1999, by and between Northern States Power Company and New Century Energies, Inc. (Exhibit 2.1 to the Report on Form 8-K (File No. 1-12907) of New Century Energies, Inc. dated March 24, 1999).
4(a)(1)*	Indenture, dated as of October 1, 1993, providing for the issuance of first mortgage bonds (Exhibit 4(a) to the Company’s Form 10-Q for the quarter ended September 30, 1993).
4(a)(2)*	Indentures supplemental to the Indenture referenced in Exhibit 4(a)(1) above:

Dated as of	Previous Filing: Form; Date or File No.	Exhibit No.
November 1, 1993	S-3, (33-51167)	4(b)(2)
January 1, 1994	10-K, 1993	4(b)(3)
September 2, 1994	8-K, Sept. 1994	4(b)
May 1, 1996	10-Q, June 30, 1996	4(b)
November 1, 1996	10-K, 1996	4(b)(3)
February 1, 1997	10-Q, March 31, 1997	4(b)
April 1, 1998	10-Q, March 31, 1998	4(b)
August 15, 2002	10-Q, Sept. 30, 2002	4.01
September 1, 2002	8-K, Sept. 18, 2002	4.01
September 15, 2002	10-Q, Sept. 30, 2002	4.02
March 1, 2003	S-3, April 14, 2003 (333-104504)	4(b)(3)
April 1, 2003	Xcel 10-Q May 15, 2003 (001-03034)	4.02
May 1, 2003	S-4, June 11, 2003 (333-106011)	4.9
September 1, 2003	8-K, Sept. 2, 2003 (001-03280)	4.02
September 15, 2003	Xcel 10-K, Mar. 15, 2004 (001-03034)	4.100
August 1, 2005	8-K, Aug. 18, 2005 (001-03280)	4.02

4(a)(3)	Form of Supplemental Indenture establishing a series of first mortgage bonds under the Indenture referenced in Exhibit 4(a)(1) above.
4(a)(4)	Form of First Mortgage Bonds (included in the Form of Supplemental Indenture referenced in Exhibit 4(a)(3) above).
4(b)(1)*	Indenture, dated July 1, 1999, providing for the issuance of senior debt securities (Exhibit 4.01 to Form 8-K dated July 13, 1999).
4(b)(2)*	Indentures supplemental to the Indenture referenced in Exhibit 4(b)(1) above:

Dated as of	Previous Filing: Form; Date or File No.	Exhibit No.
July 15, 1999	8-K, July 13, 1999	4.2

4(b)(3) Form of Supplemental Indenture establishing a series of senior debt securities under the Indenture referenced

	in Exhibit 4(b)(1) above.
4(b)(4)	Form of Senior Debt Securities (included in the Form of Supplemental Indenture referenced in Exhibit 4(b)(3) above).
5	Opinion of LeBoeuf, Lamb, Greene & MacRae LLP regarding the validity of securities.
12	Statement Regarding Computation of Ratio of Consolidated Earnings to Consolidated Fixed Charges.
23(a)	Consent of LeBoeuf, Lamb, Greene & MacRae LLP is included in its opinion referenced in Exhibit 5 above.
23(b)	Consent of Ryley Carlock & Applewhite
23(c)	Consent of Deloitte & Touche LLP
24	Power of Attorney
25(a)	Form T-1 Statement of Eligibility of U.S. Bank Trust National Association (formerly First Trust of New York, National Association), as Successor Trustee under the Indenture relating to first mortgage bonds referenced in Exhibit 4(a)(1) above.
25(b)	Form T-1 Statement of Eligibility of The Bank of New York Trust Company, N.A., as Trustee under the Indenture relating to senior debt securities referenced in Exhibit 4(b)(1) above.

*Previously filed as indicated and incorporated herein by reference.

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EX-1.(A)

Exhibit 1(a)

PUBLIC SERVICE COMPANY OF COLORADO
(a Colorado corporation)

FORM OF
UNDERWRITING AGREEMENT

(First Mortgage Bonds)

To the Representatives named in Schedule I

hereto of the Underwriters named in

Schedule II hereto

Dear Ladies and Gentlemen:

Public Service Company of Colorado, a Colorado corporation (the “Company”), proposes to sell to the underwriters named in Schedule II hereto (the “Underwriters”), for whom you are acting as representatives (the “Representatives”), its First Mortgage Bonds of the designation, with the terms and in the aggregate principal amount specified in Schedule I hereto (the “Bonds”) to be issued under its Indenture, dated as of October 1, 1993, from the Company to U.S. Bank Trust National Association, as successor trustee (the “Trustee”), as previously amended and supplemented and as to be amended and supplemented by a supplemental indenture relating to the Bonds (such Indenture as so supplemented and amended being hereinafter referred to as the “Indenture”). If the firm or firms listed in Schedule II hereto include only the firm or firms listed in Schedule I hereto, then the terms “Underwriters” and “Representatives,” as used herein, shall each be deemed to refer to such firm or firms.

1. Representations and Warranties by the Company. The Company represents and warrants to, and agrees with, each Underwriter that:

(a)

(i)The Company meets the requirements for use of Form S-3 under the Securities Act of 1933, as amended (the “Act”) and has filed with the Securities and Exchange Commission (the “Commission”) a registration statement on such Form, including a prospectus, for the registration under the Act of the Bonds, which registration statement has become effective. Such registration statement, as amended on the date of such registration statement’s effectiveness for purposes of Section 11 of the 1933 Act, as such Section applies to the Company and the Underwriters for the Bonds pursuant to Rule 430B(f)(2) under the 1933 Act (the “Effective Date”) (or upon effectiveness of any post-effective amendment thereto), including the information, if any, deemed pursuant to Rule 430A, 430B or 430C under the Act or under the Securities Exchange Act of 1934 to be part of the registration statement at the time of its effectiveness (“Rule 430 Information”), are collectively referred to herein as the “Registration Statement.”  Each prospectus used before the registration statement became effective, and any prospectus or prospectus supplement that omitted Rule 430 Information that was used after such effectiveness and prior to the execution and delivery of this Agreement is herein called a “preliminary prospectus.”  The preliminary prospectus supplement dated             , including the accompanying prospectus dated         , is herein called the “Preliminary Prospectus.”  The prospectus, in the form first filed under Rule 424(b) under the Act after the date and time this Agreement is executed, is herein called the “Prospectus”;

(ii)The Company will file with the Commission the Prospectus, which will include a prospectus supplement (the “Prospectus Supplement”) relating to the Bonds, pursuant to Rule 424 under the Act. Copies of such Registration Statement, the Preliminary Prospectus and Prospectus, any such amendment or supplement and all documents incorporated by reference therein which were filed with the Commission on or prior to the date of this Agreement have been delivered to you and copies of the Prospectus Supplement will be delivered to you promptly after it is filed with the Commission; and

(iii)Unless specifically noted otherwise herein, any reference herein to the Registration Statement, the Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 which were filed under the Securities Exchange Act of 1934, as amended (the “Exchange Act”) as of each effective date for purposes of the Registration Statement or on or before the date hereof for purposes of the Preliminary Prospectus or the Prospectus. If the Company files any document pursuant to the Exchange Act after the date of this Agreement and prior to the termination of the offering of the Bonds by the Underwriters, which document is deemed to be incorporated by reference into the Prospectus, the term “Prospectus” shall refer also to said prospectus as supplemented by the document so filed from and after the time said document is filed with the Commission; any reference to any amendment to the Registration Statement shall be deemed to refer to and include (A) any annual report of the Company filed pursuant to Section 13(c) or 15(d) of the Exchange Act after the effective date of the Registration Statement that is incorporated by reference in the Registration Statement and (B) any Prospectus Supplement relating to the Bonds. There are no contracts or documents of the Company that are required to be filed as exhibits to the Registration Statement or any documents incorporated by reference therein by the Act, the Exchange Act or the rules and regulations thereunder which have not been so filed.

For purposes of this Agreement, the “Time of Sale” is       :        (New York Time) on the date of this Agreement.

(b)No stop order suspending the effectiveness of the Registration Statement has been issued and no proceeding for that purpose or pursuant to Section 8A of the Act has been initiated or, to the best knowledge of the Company, threatened by the Commission and no order preventing or suspending the use of any preliminary prospectus or the Prospectus has been issued by the Commission;

(c)The Registration Statement, when it became effective, conformed, and any further amendments thereto, when they become effective, will conform, in all material respects to the requirements of the Act and the Trust Indenture Act of 1939, as amended (the “Trust Indenture Act”), and the Prospectus and any amendments or supplements thereto, when filed with the Commission, will conform in all material respects to the requirements of the Act and the Trust Indenture Act;

(d)The Registration Statement, on the Effective Date, did not and any further amendments thereto when they become effective, will not, contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading; as of the Time of Sale, the Preliminary Prospectus and each “free-writing prospectus” (as defined pursuant to Rule 405 under the Act) listed on Schedule IV hereto (collectively, the “Time of Sale Information”) and without regard to any Prospectus Supplement or documents incorporated by reference that were filed after the Time of Sale, did not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements made, in light of the circumstances under which they were made, not misleading; and the Prospectus as of its date and any amendments and supplements thereto, as of the time when they are filed or transmitted for filing with the Commission, and at the Closing Date (as defined below), will not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements made, in light of the circumstances under which they were made, not misleading; provided, however, that the representations and warranties contained in this subsection (d) shall not apply to statements or omissions made in reliance upon and in conformity with information furnished in writing by an Underwriter through the Representatives expressly for use in the Registration Statement, the Time of Sale Information, Prospectus or any amendment or supplement to any thereof;

(e)The documents incorporated by reference in the Registration Statement, the Time of Sale Information or Prospectus, when they were filed with the Commission, and any further documents so filed and incorporated by reference, when they are filed with the Commission or become effective, as the case may be, complied with and will comply in all material respects with the requirements of the Exchange Act or the Act, as the case may be;

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(f)The Company is not, and after giving effect to the offering and sale of the Bonds and the application of the proceeds thereof as described in the Prospectus will not be, an “investment company” or an entity “controlled” by an “investment company” within the meaning of the Investment Company Act of 1940, as amended, without taking account of any exemption arising out of the number of holders of the Company’s securities;

(g)The statements in the Prospectus under the headings “Supplemental Description of the First Mortgage Bonds” and “Description of the First Mortgage Bonds” fairly summarize the matters therein described;

(h)This Agreement has been duly authorized, executed and delivered by the Company;

(i)The Indenture has been duly authorized and the Indenture (excluding the Supplemental Indenture) has been duly executed and delivered by the Company and is in due and proper form and (assuming the Indenture has been duly authorized, executed and delivered by the Trustee) when the Supplemental Indenture is duly executed and delivered the Indenture will constitute a legal, valid and binding obligation of the Company, enforceable in accordance with its terms, except as enforcement thereof may be limited by laws and principles of equity affecting generally the enforcement of mortgagees’ and other creditors’ rights, including, without limitation, bankruptcy and insolvency laws and state laws which affect the enforcement of certain remedial provisions of the Indenture; provided, however, that such state laws will not render the remedies afforded by the Indenture inadequate for the practical realization of the benefit of the security provided thereby;

(j)The issuance and sale by the Company of the Bonds pursuant to this Agreement have been duly authorized by all necessary corporate action; and, when issued, authenticated and delivered to the Underwriters pursuant to this Agreement against payment of the consideration therefor specified herein, the Bonds will be valid and binding obligations of the Company, enforceable in accordance with their terms, except as enforcement thereof may be limited by laws or principles of equity affecting generally the enforcement of mortgagees’ and other creditors’ rights, including, without limitation, bankruptcy and insolvency laws, and state laws which affect the enforcement of certain remedial provisions of the Indenture and will be entitled to the benefits of the Indenture;

(k)The issuance and sale of the Bonds have been duly authorized and approved by an order of the Public Utilities Commission of the State of Colorado and such order is final and in full force and effect on the date hereof, the time for appeal therefrom or review thereof or intervention with respect thereto having expired; no further approval, authorization, consent or other order of any public board or body is legally required in connection with the transactions contemplated by this Agreement and the Indenture, except for the registration under the Act of the Bonds and as may be required under the blue sky laws of any jurisdiction in connection with the purchase and distribution of the Bonds by the Underwriters in the manner contemplated herein and in the Prospectus;

(l)Neither the execution and delivery of this Agreement or the Supplemental Indenture, the issue and sale of the Bonds, nor the consummation of any other of the transactions herein or therein contemplated, nor the fulfillment of the terms hereof or thereof will conflict with, result in a breach or violation or imposition of any lien, charge or encumbrance upon any property or assets of the Company or any of its subsidiaries, other than the liens and security interests created by the Indenture, pursuant to, (i) the charter or by-laws of the Company or any of its subsidiaries; (ii) the terms of any indenture, contract, lease, mortgage, deed of trust, note agreement, loan agreement or other agreement, obligation, condition, covenant or instrument to which the Company or any of its subsidiaries is a party or bound or to which its property is subject; or (iii) any statute, law, rule, regulation, judgment, order or decree applicable to the Company of any court, regulatory body, administrative agency, governmental body, arbitrator or other authority having jurisdiction over the Company or any of its subsidiaries or any of its or their properties except, in the case of clause (ii), any such conflict, default, breach or violation which would not, individually or in the

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aggregate, have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries taken as a whole, whether or not arising from transactions in the ordinary course of business;

(m)The Company has good title to the properties specifically or generally described or referred to in the Indenture as subject to the lien thereof (except such property as may have been sold, exchanged or otherwise disposed of) subject only to, in the case of such properties which are used or to be used in or in connection with the Electric Utility Business (as defined in the Indenture) (whether or not such is the sole use of such property), the lien of the Indenture and Permitted Liens (as defined in the Indenture);

(n)The Indenture constitutes a mortgage lien on the properties specifically or generally described or referred to therein as subject to the lien thereof (except such properties as may have been sold, exchanged or otherwise disposed of or released from the lien thereof in accordance with the terms thereof) subject to no liens prior to the lien of the Indenture other than Permitted Liens; and the Indenture by its terms effectively subjects to the lien thereof all property (except property of the kinds specifically excepted from the lien of the Indenture) acquired by the Company after the date of execution and delivery of the Indenture and used or to be used in or in connection with the Electric Utility Business, subject to Permitted Liens, any lien thereon existing at the time of such acquisition and to any liens for unpaid portions of the purchase money placed thereon at the time of such acquisition, and also subject to the provisions of Article Thirteen of the Indenture and to certain possible claims of a trustee in bankruptcy and possible claims and taxes of the federal government;

(o)The consolidated historical financial statements and schedules of the Company and its consolidated subsidiaries included or incorporated by reference in the Registration Statement, Time of Sale Information and Prospectus present fairly in all material respects the financial condition, results of operations, cash flows and changes in financial position of the Company as of the dates and for the periods indicated, comply as to form with the applicable accounting requirements of the Act and the Exchange Act and have been prepared in conformity with U.S. generally accepted accounting principles (“GAAP”) throughout the periods involved (except as otherwise noted therein) and comply, and at the Closing Date will comply, in all material respects with the requirements of paragraph (e) of Item 10 of Regulation S-K; the selected financial data set forth under the caption “Selected Consolidated Financial Data” in the Prospectus fairly present, on the basis stated in the Prospectus, the information included therein. Except as disclosed in or incorporated by reference in the Registration Statement, Time of Sale Information and Prospectus, neither the Company nor any of its subsidiaries has any contingent obligations which are material to the Company and its consolidated subsidiaries taken as a whole;

(p)Deloitte & Touche LLP, which audited the financial statements incorporated by reference in the Registration Statement and Prospectus, (i) is an independent registered public accounting firm as required by the Act and the rules and regulations of the Commission thereunder and (ii) is in compliance with its obligations under the Exchange Act with respect to the Company;

(q)The statistical and market-related data and forward-looking statements (within the meaning of Section 27A of the Act and Section 21E of the Exchange Act) included or incorporated by reference in the Time of Sale Information and Prospectus are based on or derived from sources that the Company believes to be reliable and accurate in all material respects and represent good faith estimates that are made on the basis of data derived from such sources;

(r)Except as may otherwise be reflected in or contemplated by the Registration Statement, Time of Sale Information and Prospectus, since the respective dates as of which information is given in the Registration Statement, Time of Sale Information and Prospectus (i) there has been no material adverse change in the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries taken as a whole, whether or not arising from transactions in the ordinary course of business and (ii) neither the Company nor any of its

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subsidiaries has entered into any transactions which are material to the Company, other than in the ordinary course of business; and, except as so reflected or contemplated, neither the Company nor any of its subsidiaries has any contingent obligations which are material to the Company and its subsidiaries as a whole;

(s)Each of the Company and its subsidiaries has been duly incorporated and is validly existing as a corporation in good standing under the laws of the jurisdiction in which it is chartered or organized with full corporate power and authority to own or lease, as the case may be, and to operate its properties and conduct its business as described in the Registration Statement, Time of Sale Information and Prospectus, and is duly qualified to do business as a foreign corporation and is in good standing under the laws of each jurisdiction in which such qualification is required, whether by reason of the ownership or leasing of property or the conduct of business, except where the failure to be so qualified would not have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries taken as a whole, whether or not arising from transactions in the ordinary course of business;

(t)All of the outstanding shares of capital stock of each subsidiary have been duly and validly authorized and issued and are fully paid and nonassessable, and, except as otherwise set forth in the Registration Statement, Time of Sale Information and Prospectus, all outstanding shares of capital stock of the subsidiaries are owned by the Company either directly or through wholly-owned subsidiaries free and clear of any perfected security interest or any other security interests, claims, liens or encumbrances;

(u)The Company has no subsidiaries which would be deemed significant subsidiaries under Regulation S-X;

(v)Neither the Company nor any of its subsidiaries is in conflict, violation, breach or default of (i) any provision of its charter or bylaws; (ii) the terms of any indenture, contract, lease, mortgage, deed of trust, note agreement, loan agreement or other agreement, obligation, condition, covenant or instrument to which it is a party or bound or to which its property is subject; or (iii) any statute, law, rule, regulation, judgment, order or decree applicable to the Company or any of its subsidiaries of any court, regulatory body, administrative agency, governmental body, arbitrator or other authority having jurisdiction over the Company or such subsidiary or any of its properties, as applicable except, in the case of clause (ii) or (iii), any such conflict, violation, breach or default which would not, individually or in the aggregate, (x) have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries taken as a whole, whether or not arising from transactions in the ordinary course of business and (y) impair the validity of the Bonds;

(w)No subsidiary of the Company is currently prohibited, directly or indirectly, from paying any dividends to the Company, from making any other distribution on such subsidiary’s capital stock, from repaying to the Company any loans or advances to such subsidiary from the Company or from transferring any of such subsidiary’s property or assets to the Company or any other subsidiary of the Company, except as described in or contemplated by the Registration Statement, Time of Sale Information and Prospectus;

(x)Neither the Company, nor any of its subsidiaries, nor any director, officer, agent, employee or other person or entity acting on behalf of the Company or any of its subsidiaries has, in the course of its actions for, or on behalf of, the Company, used any corporate funds for any unlawful contribution, gift, entertainment or other unlawful expenses relating to political activity; made any direct or indirect unlawful payment to any foreign or domestic government official or employee from corporate funds; or made any unlawful bribe, rebate, payoff, influence payment, kickback or other unlawful payment to any foreign or domestic government official or employee;

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(y)(i) the Company has devised and established and maintains the following, among other, internal controls (without duplication): (A) a system of “internal accounting controls” as contemplated in Section 13(b)(2)(B) of the 1934 Act; (B) “disclosure controls and procedures” as such term is defined in Rule 13a-15(e) under the 1934 Act; and (C) “internal control over financing reporting” (as such term is defined in Rule 13a-15(f) under the 1934 Act (the internal controls referred to in clauses (A) and (B) above and this clause (C) being hereinafter called, collectively, the “Internal Controls”); (ii) the Internal Controls are evaluated by the Company’s senior management periodically as appropriate and, in any event, as required by law; and (iii) based on the most recent evaluations of the Internal Controls, (A) the Internal Controls are, individually and in the aggregate, effective in all material respects to perform the functions for which they were established; and (B) all material weaknesses, if any, and significant deficiencies, if any, in the design or operation of the Internal Controls which are reasonably likely to adversely affect the Company’s ability to record, process, summarize and report financial information and any fraud, whether or not material, that involves management or other employees who have a significant role in the Internal Controls have been disclosed to the Company’s independent auditors and the audit committee of the Company’s board directors.

(z)Except as set forth in, or incorporated by reference in, the Registration Statement, Time of Sale Information and Prospectus, the Company and its subsidiaries (i) are in compliance with any and all applicable federal, state and local laws and regulations relating to the protection of human health and safety, the environment or hazardous or toxic substances or wastes, pollutants or contaminants (“Environmental Laws”), (ii) have received all permits, licenses or other approvals required of them under applicable Environmental Laws to conduct their respective businesses, (iii) are in compliance with all terms and conditions of any such permits, licenses or approvals, and (iv) have not received notice of any actual or potential liability for the investigation or remediation of any disposal or release of hazardous or toxic substances or wastes, pollutants or contaminants, except where such non-compliance with Environmental Laws, failure to receive required permits, licenses or other approvals, or any such liability would not, individually or in the aggregate, have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business;

(aa)With respect to each employee benefit plan (as defined in Section 3(3) of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”)) which the Company or any other organization that together with the Company is treated as a single employer under Sections 414(b), (c), (m) or (o) of the Internal Revenue Code of 1986, as amended (the “Code”) (an “ERISA Affiliate”), has at any time sponsored, maintained, contributed to or been obligated to contribute to (a “Plan”): (i) the Company and each ERISA Affiliate have administered and operated each Plan sponsored or maintained by the Company or an ERISA Affiliate in compliance with ERISA, the Code and other applicable laws except for such instances of noncompliance as have not resulted in and could not reasonably be expected to result in a material liability to the Company or ERISA Affiliate; (ii) each Plan sponsored or maintained by the Company or an ERISA Affiliate intended to qualify under Section 401(a) of the Code so qualifies and to the Company’s knowledge nothing has occurred, whether by action or failure to act, which could reasonably be expected to cause the loss of such qualification of any such Plan; (iii) neither the Company nor any ERISA Affiliate has incurred, and to the Company’s knowledge no event, transaction or condition has occurred or exists under which the Company or any ERISA Affiliate could reasonably expect to incur, any material liability or the imposition of any lien on any of the rights, properties or assets of the Company or any ERISA Affiliate pursuant to Title I or Title IV of ERISA (other than routine claims for benefits) or applicable penalty or excise provisions of the Code; (iv) there has been no reportable event (within the meaning of Section 4043 of ERISA) with respect to any Plan subject to Title IV of ERISA that is sponsored or maintained by the Company or an ERISA Affiliate for which the 30-day reporting requirement has not been waived which could reasonably be expected to result in a material liability under Title IV of ERISA to the Company or an ERISA Affiliate; (v) no accumulated funding deficiency (within the meaning of Section 302 of ERISA and Section 412 of the Code), whether or not waived, exists with respect to

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any Plan subject to Title IV of ERISA that is sponsored or maintained by the Company; and (vi) neither the Company nor any ERISA Affiliate has incurred, and to the Company’s knowledge no event, transaction or condition has occurred or exists under which the Company or any ERISA Affiliate could reasonably expect to incur, any material liability with respect to termination of, or withdrawal from, any Plan subject to Title IV of ERISA;

(bb)The franchises held by the Company and its subsidiaries, together with the applicable Certificates of Convenience and Necessity issued by the Public Utilities Commission of the State of Colorado, give the Company and such subsidiaries all necessary authority for the maintenance and operation of their respective properties and business as now conducted, and are free from burdensome restrictions or conditions of an unusual character.

(cc)The Company is not an “ineligible issuer” as defined under the Act.

(dd)The Company is in compliance in all material respects with the Sarbanes-Oxley Act of 2002 and the rules and regulations of the Commission thereunder, to the extent that such Act and such rules are in effect and applicable to the Company.

(ee)The Company has complied and will comply with the requirements of Rule 433 under the Act applicable to any free-writing prospectus, including timely filing with the Commission and legending.

Any certificate signed by any officer of the Company and delivered to the Representatives or counsel for the Representatives in connection with the offering of the Bonds shall be deemed a representation and warranty by the Company, as to matters covered thereby, to each Underwriter.

2. Purchase and Sale. Subject to the terms and conditions and in reliance upon the representations and warranties herein set forth, the Company agrees to sell to the Representatives and each other Underwriter, and the Representatives and each other Underwriter agree, severally and not jointly, to purchase from the Company, at the purchase price set forth in Schedule I hereto, the respective principal amounts of the Bonds set forth opposite their respective names in Schedule II hereto.

3. Delivery and Payment. Delivery of and payment for the Bonds shall be made at the place, date and time specified in Schedule I hereto, which date and time may be postponed by agreement between the Representatives and the Company (such date and time being herein called the “Closing Date”). Delivery of the Bonds shall be made to the Representatives for the respective accounts of the several Underwriters against payment by the several Underwriters through the Representatives of the purchase price thereof to or upon the order of the Company by wire transfer payable in same-day funds to the account specified by the Company. The Bonds will be delivered in global registered form except that, if for any reason the Company is unable to deliver the Bonds in global form, the Company reserves the right, as provided in the Indenture, to make delivery in temporary form. Any Bonds delivered in temporary form will be exchangeable without charge for Bonds in definitive form. Unless otherwise indicated on Schedule I, the Bonds will be registered in the name of Cede & Co., as nominee of The Depository Trust Company and in the principal amounts set forth in Schedule II hereto. The Bonds will be made available to the Representatives for checking in New York, New York, not later than 2:00 p.m., New York City time, on the Business Day preceding the Closing Date.

4. Agreements. The Company agrees with the several Underwriters as follows:

(a)The Company shall prepare the Prospectus in a form approved by the Representatives and to file such Prospectus pursuant to Rule 424(b) under the Act not later than the Commission’s close of business on the second Business Day following the execution and delivery of this Agreement; to make no further amendment or any supplement to the Registration Statement or Prospectus prior to the Closing Date which shall be reasonably disapproved by the Representatives promptly after reasonable notice thereof; during the period for which a prospectus is required to be delivered

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under the Act in connection with the offering and sale of the Bonds, to advise the Representatives, promptly after it receives notice thereof, of the time when any amendment to the Registration Statement has been filed or becomes effective or any supplement to the Prospectus or any amended Prospectus has been filed and to furnish the Representatives with copies thereof; to file promptly all reports and any definitive proxy or information statements required to be filed by the Company with the Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the date of the Prospectus and for so long as the delivery of a prospectus is (or in lieu thereof, the Notice referred to in Rule 173(a) under the Act) required under the Act in connection with the offering or sale of the Bonds; to make any other required filings pursuant to Rule 433(d)(1) of the Act within the time required by such Rules; to advise the Representatives, promptly after it receives notice thereof, of the issuance by the Commission of any stop order or of any order preventing or suspending the use of any prospectus, of the suspension of the qualification of the Bonds for offering or sale in any jurisdiction, of the initiation or threatening of any proceeding for any such purpose, or of any request by the Commission for the amending or supplementing of the Registration Statement or the Prospectus or for additional information; to use its best efforts to prevent the issuance of any stop order or of any order preventing or suspending the use of any prospectus or suspending any such qualification, and, in the event of the issuance of any such order, promptly to use its best efforts to obtain the withdrawal of such order;

(b)The Company shall promptly from time to time take such action as the Representatives may reasonably request to qualify the Bonds for offering and sale under the securities laws of such jurisdictions as the Representatives may request and to comply with such laws so as to permit the continuance of sales and dealings therein in such jurisdictions for as long as may be necessary to complete the distribution of the Bonds, provided that in connection therewith the Company shall not be required to qualify as a foreign corporation or to file a general consent to service of process in any jurisdiction;

(c)The Company shall prior to 10:00 a.m., New York City time, on the        Business Day next succeeding the date of this Agreement and from time to time, furnish the Underwriters with written and electronic copies of the Prospectus in such quantities as the Representatives may from time to time reasonably request, and, if the delivery of a prospectus (or in lieu thereof, the Notice referred to in Rule 173(a) under the Act) is required under the Act at any time in connection with the offering or sale of the Bonds and if at any time any event shall have occurred as a result of which the Time of Sale Information or Prospectus as then amended or supplemented conflict with the information contained in the Registration Statement, the Preliminary Prospectus or the Prospectus or would include an untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made when such Time of Sale Information or Prospectus (or in lieu thereof, the Notice referred to in Rule 173(a) under the Act) is delivered, not misleading, or, if for any other reason it shall be necessary during such period to amend or supplement the Time of Sale Information or Prospectus or to file under the Exchange Act any document incorporated by reference in the Time of Sale Information or Prospectus in order to comply with the Act, the Exchange Act or the Trust Indenture Act, to notify the Representatives promptly and upon their reasonable request to file such document and to prepare and furnish without charge to each Underwriter and to any dealer in securities as many written and electronic copies as the Representatives may from time to time reasonably request of an amendment or supplement to the Time of Sale Information or Prospectus which will correct such conflict, statement or omission or effect such compliance;

(d)The Company shall make generally available to its securityholders and to the Representatives as soon as practicable, but in any event not later than eighteen months after the effective date of the Registration Statement (as defined in Rule 158), an earnings statement of the Company and its subsidiaries (which need not be audited) complying with Section 11(a) of the Act and the rules and regulations thereunder including Rule 158;

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(e)The Company shall not for a period of        days following the Execution Time, without the prior written consent of the Representatives, offer, sell or contract to sell, or otherwise dispose of (or enter into any transaction which is designed to, or might reasonably be expected to, result in the disposition (whether by actual disposition or effective economic disposition due to cash settlement or otherwise) by the Company, directly or indirectly, or announce the offering of) any long-term Bonds issued or guaranteed by the Company, other than the Bonds;

(f)The Company shall use the net proceeds received by it from the sale of the Bonds pursuant to this Agreement in the manner specified in the Time of Sale Information and the Prospectus under the caption “Use of Proceeds”;

(g)The Company shall pay the costs and expenses relating to the following matters: (i) the preparation of the Supplemental Indenture, the issuance of the Bonds and the fees of the Trustee; (ii) the preparation, printing and filing of the Registration Statement (including all exhibits thereto), the Preliminary Prospectus, the Prospectus (including all documents incorporated by reference therein), the Time of Sale Information and any amendments thereof or supplements thereto and the printing and furnishing of such copies of each thereof to the Underwriters and to dealers (including postage, air freight charges and charges for counting and packaging), as may be reasonably requested for use in connection with the offering and sale of the Bonds; (iii) the preparation, printing, authentication, issuance and delivery of certificates for the Bonds, including any stamp or transfer taxes in connection with the original issuance and sale of the Bonds; (iv) the printing (or reproduction) and delivery of this Agreement, any blue sky memorandum and all other agreements or documents printed (or reproduced) and delivered in connection with the offering of the Bonds; (v) any registration or qualification of the Bonds for offer and sale under the securities or blue sky laws of the several states (including filing fees and the reasonable fees and expenses of counsel for the Underwriters relating to such registration and qualification); (vi) the transportation and other expenses incurred by or on behalf of Company representatives in connection with presentations to prospective purchasers of the Bonds; (vii) the fees and expenses of the Company’s accountants and counsel (including local and special counsel); (viii) the fees and expenses of any rating agencies rating the Bonds and (ix) all other costs and expenses incident to the performance by the Company of its obligations hereunder;

(h)Other than the Time of Sale Information listed on Schedule IV, without prior consent of the Representatives, it has not made and will not make any offer relating to the Bonds that would constitute a “free-writing prospectus” (as defined pursuant to Rule 405 under the Act).

(i)The Company will, pursuant to reasonable procedures developed in good faith, retain, as and to the extent required under Rule 433 of the Act, copies of each Issuer Free Writing Prospectus (as defined in Rule 433) that is not filed with the Commission in accordance with Rule 433 under the Act.

5. Certain Agreements of the Underwriters. Each Underwriter hereby represents and agrees as follows:

(a)It has not and will not use, authorize use of, refer to, or participate in the planning for use of, any “free writing prospectus,” as defined in Rule 405 under the Act (which term includes use of any written information furnished to the Commission by the Company and not incorporated by reference into the Registration Statement and any press release issued by the Company) other than (i) a free writing prospectus that contains no “issuer information” (as defined in Rule 433(h)(2) under the Act) that was not included (including through incorporation by reference) in the Preliminary Prospectus or a previously filed Issuer Free Writing Prospectus, (ii) any Issuer Free Writing Prospectus listed on Schedule IV hereto, or (iii) any free writing prospectus prepared by such Underwriter and approved by the Company in advance in writing (each such free writing prospectus referred to in clauses (i) or (iii), an “Underwriter Free Writing Prospectus”);

(b)It has not and will not distribute any Underwriter Free Writing Prospectus referred to in clause (a)(i) or (a)(iii) in a manner reasonably designed to lead to its broad unrestricted dissemination;

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(c)It has not and will not, without the prior written consent of the Company, use any free writing prospectus that contains the final terms of the Bonds unless such terms have previously been included in a free writing prospectus filed with the Commission; provided that the Underwriters may use a term sheet substantially in the form of Schedule III hereto without the consent of the Company provided further that any Underwriter using such term sheet shall notify the Company, and provide a copy of such term sheet to the Company, prior to, or substantially concurrently with, the first use of such term sheet;

(d)It will, pursuant to reasonable procedures developed in good faith, retain, as and to the extent required under Rule 433 of Act, copies of each free writing prospectus used or referred to by it, in accordance with Rule 433 under the Act;

(e)It  is not subject to any pending proceeding under Section 8A of the Act with respect to the offering (and will promptly notify the Company if any such proceeding against it is initiated).

6. Conditions to the Obligations of the Underwriters. The obligations of the Underwriters to purchase the Bonds shall be subject to the accuracy of the representations and warranties on the part of the Company contained herein as of the date hereof and as of the Closing Date, to the accuracy of the statements of the Company made in any certificates delivered pursuant to the provisions hereof, to the performance by the Company of its obligations hereunder and to the following additional conditions:

(a)The Prospectus Supplement relating to the Bonds shall have been filed with the Commission pursuant to Rule 424(b) within the applicable time period prescribed for such filing by the rules and regulations under the Act and in accordance with Section 4(a) hereof; no stop order suspending the effectiveness of the Registration Statement or any part thereof shall have been issued and no proceeding for that purpose or pursuant to Section 8A shall have been initiated or threatened by the Commission; and all requests for additional information on the part of the Commission shall have been complied with to the Representatives’ reasonable satisfaction;

(b)The Representatives shall be furnished with opinions, dated the Closing Date, of Paula M. Connelly, Assistant General Counsel of Xcel Energy Services, Inc., attorney for the Company, LeBoeuf, Lamb, Green & MacRae LLP, counsel for the Company, Ryley Carlock & Applewhite, counsel for the Company, and Jones Day, counsel for the Company, substantially in the forms included as Exhibits A, B, C and D, respectively;

(c)The Representatives shall have received from Dewey Ballantine LLP, counsel for the Underwriters, such opinion or opinions dated the Closing Date with respect to such matters as the Representatives may reasonably require, and the Company shall have furnished to such counsel such documents as they reasonably request for the purpose of enabling them to pass upon such matters;

(d)The Company shall have furnished to the Representatives a certificate of the President or any Vice President of the Company, dated the Closing Date, as to the matters set forth in clause (a) and (h) of this Section 6 and to the further effect that the signers of such certificate have carefully examined the Registration Statement, the Prospectus, the Time of Sale Information and this Agreement and that:

(i)            the representations and warranties of the Company in this Agreement are true and correct on and as of the Closing Date with the same effect as if made on the Closing Date, and the Company has complied with all the agreements and satisfied all the conditions on its part to be performed or satisfied at or prior to the Closing Date; and

(ii)           since the date of the most recent financial statements included or incorporated by reference in the Prospectus and the Time of Sale Information, there has been no material adverse change in the condition of the Company, financial or otherwise, or in the earnings, affairs or

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business prospects of the Company, whether or not arising in the ordinary course of business, from that set forth or contemplated by the Registration Statement, the Time of Sale Information on the Prospectus;

(e)The Representatives shall have received letters from Deloitte & Touche LLP, independent public accountant for the Company (dated the date of this Agreement and Closing Date, respectively, and in form and substance satisfactory to the Representatives) advising that (i) they are an independent registered public accounting firm with respect to the Company as required by the Act and published rules and regulations of the Commission thereunder, (ii) in their opinion, the financial statements and supplemental schedules incorporated by reference in the Registration Statement, the Time of Sale Information or Prospectus and covered by their opinion filed with the Commission under Section 13 of the Exchange Act comply as to form in all material respects with the applicable accounting requirements of the Exchange Act and the published rules and regulations of the Commission thereunder, (iii) they have performed limited procedures, not constituting an audit, including a reading of the latest available interim financial statements of the Company, a reading of the minutes of meetings of the Board of Directors, committees thereof, and of the Shareholder of the Company since the date of the most recent audited financial statements included or incorporated by reference in the Prospectus and the Time of Sale Information, inquiries of officials of the Company responsible for financial accounting matters and such other inquiries and procedures as may be specified in such letter, and on the basis of such limited review and procedures nothing came to their attention that caused them to believe that: (A) any material modifications should be made to any unaudited financial statements of the Company included or incorporated by reference in the Registration Statement, the Time of Sale Information or Prospectus for them to be in conformity with generally accepted accounting principles or that any unaudited consolidated financial statements of the Company included or incorporated by reference in the Registration Statement, the Time of Sale Information or Prospectus do not comply as to form in all material respects with the applicable accounting requirements of the Exchange Act and the rules and regulations of the Commission applicable to Form 10-Q; (B) with respect to the period subsequent to the date of the most recent financial statements included or incorporated by reference in the Prospectus and except as set forth in or contemplated by the Registration Statement, the Time of Sale Information or Prospectus, there were any changes, at a specified date not more than five Business Days prior to the date of the letter, in the capital stock of the Company, increases in long-term debt or decreases in stockholders’ equity or net current assets of the Company as compared with the amounts shown on the most recent consolidated balance sheet included or incorporated in the Prospectus and the Time of Sale Information, or for the period from the date of the most recent financial statements included or incorporated by reference in the Prospectus and the Time of Sale Information to such specified date there were any decreases, as compared with the corresponding period in the preceding year, in operating revenues, operating income or net income of the Company, except in all instances for changes or decreases set forth in such letter, in which case the letter shall be accompanied by an explanation by the Company as to the significance thereof unless said explanation is not deemed necessary by the Representatives; and (iv) they have carried out specified procedures performed for the purpose of comparing certain specified financial information and percentages (which is limited to financial information derived from general accounting records of the Company or, to the extent not so derived, from schedules prepared by Company officers responsible for such accounting records) included or incorporated by reference in the Registration Statement, the Time of Sale Information and Prospectus with indicated amounts in the financial statements or accounting records of the Company and (excluding any questions of legal interpretation) have found such information and percentages to be in agreement with the relevant accounting and financial information of the Company referred to in such letter in the description of the procedures performed by them;

(f)Subsequent to the respective dates as of which information is given in the Registration Statement, Time of Sale Information and the Prospectus, there shall not have been (i) any change or decrease specified in the letter or letters referred to in paragraph (e) of this Section 6; or (ii) any change, or any development involving a prospective change, in or affecting the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken

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as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated in the Registration Statement, the Time of Sale Information and Prospectus the effect of which, in any case referred to in clause (i) or (ii) above, is, in the sole judgement of the Representatives, material and adverse and makes it impracticable or inadvisable to market the Bonds as contemplated by the Prospectus and the Time of Sale Information;

(g)Subsequent to the date hereof, there shall not have been any decrease in the rating or outlook of any of the Company’s Bonds by any “nationally recognized statistical rating organization” (as defined for purposes of Rule 436(g)(2) under the Act) or any public announcement of any intended or potential decrease in any such rating or outlook or of a possible change in any such rating or outlook that does not indicate the direction of the possible change;

(h)The Company shall have complied with the provisions of Section 4(c) hereof with respect to the furnishing of prospectuses;

(i)Prior to the Closing Date, the Company shall have furnished to the Representatives such further information, certificates and documents as the Representatives may reasonably request.

If any of the conditions specified in this Section 6 shall not have been fulfilled in all material respects when and as provided in this Agreement, or if any of the opinions and certificates mentioned above or elsewhere in this Agreement shall not be in all material respects reasonably satisfactory in form and substance to the Representatives and their counsel, this Agreement and all obligations of the Underwriters hereunder may be cancelled at, or at any time prior to, the Closing Date by the Representatives. Notice of such cancellation shall be given to the Company in writing, or by telephone or telegraph confirmed in writing.

7. Conditions of Company’s Obligations. The obligations of the Company to sell and deliver the Bonds are subject to the following conditions:

(a)Prior to the Closing Date, no stop order suspending the effectiveness of the Registration Statement shall have been issued and no proceedings for that purpose shall have been instituted or, to the knowledge of the Company or the Representatives, threatened;

(b)At the Closing Date, the order of the Public Utilities Commission of the State of Colorado authorizing and approving the issuance and sale of the Bonds shall be final and in full force and effect and the time for appeal therefrom or review thereof or intervention with respect thereto shall have expired.

If any of the conditions specified in this Section 7 shall not have been fulfilled, this Agreement and all obligations of the Company hereunder may be cancelled on or at any time prior to the Closing Date by the Company. Notice of such cancellation shall be given to the Underwriters in writing or by telephone or facsimile transmission confirmed in writing.

8. Reimbursement of Underwriters’ Expenses.  If the sale of the Bonds provided for herein is not consummated because any condition to the obligations of the Underwriters set forth in Section 6 hereof is not satisfied or because of any refusal, inability or failure on the part of the Company to perform any agreement herein or comply with any provision hereof, other than by reason of a default by any of the Underwriters, the Company will reimburse the Underwriters severally upon demand for all out-of-pocket expenses that shall have been reasonably incurred by them in connection with the proposed purchase and sale of the Bonds, including the reasonable fees and disbursements of counsel for the Underwriters.

9. Indemnification.

(a)The Company agrees to indemnify and hold harmless each Underwriter, the directors, members, officers, employees and agents of each Underwriter and each person who controls any Underwriter within the meaning of either the Act or the Exchange Act against any and all losses, claims, damages or liabilities, joint or several, to which they or any of them may become subject under the

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Act, the Exchange Act or other Federal or state statutory law or regulation, at common law or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement or any amendment thereto, in the Time of Sale Information or Issuer Free Writing Prospectus or in the Prospectus or any amendment or supplement thereto, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, and agrees to reimburse each such indemnified party, as incurred, for any legal or other expenses reasonably incurred by them in connection with investigating or defending any such loss, claim, damage, liability or action; provided, however, that the Company will not be liable in any such case to the extent that any such loss, claim, damage or liability arises out of or is based upon any such untrue statement or alleged untrue statement or omission or alleged omission made in the Registration Statement or any amendment thereto, in the Time of Sale Information or any Issuer Free Writing Prospectus or in the Prospectus or any amendment or supplement thereto, in reliance upon and in conformity with written information furnished to the Company by or on behalf of any Underwriter through the Representatives specifically for inclusion therein; provided, further, that with respect to any such untrue statement in or omission from any Time of Sale Information or Issuer Free Writing Prospectus, the indemnity contained in this paragraph (a) shall not inure to the benefit of any Underwriter or its directors, members, officers, employees and agents, and each person, if any, who controls such Underwriter to the extent that the sale to the person asserting any such loss, claim, damage or liability was an initial sale by such Underwriter and any such loss, claim, damage or liability of or with respect to such Underwriter results from the fact that both (i) to the extent required by applicable law, a copy of all of the Time of Sale Information (including each Issuer Free Writing Prospectus specified in Schedule IV) was not sent or given to such person at or prior to the sale of the Bonds to such person and (ii) the untrue statement in or omission from such Time of Sale Information or Issuer Free Writing Prospectus was corrected in the undelivered Time of Sale Information unless, in either case, such failure to deliver all of the Time of Sale Information was a result of non-compliance by the Company with the provisions of Section 4(c) hereof. This indemnity agreement will be in addition to any liability which the Company may otherwise have;

(b)Each Underwriter severally and not jointly agrees to indemnify and hold harmless the Company, and each of its directors, officers, employees and agents, and each person who controls the Company within the meaning of either the Act or the Exchange Act, to the same extent as the foregoing indemnity from the Company to each Underwriter, but only with reference to written information relating to such Underwriter furnished to the Company by or on behalf of such Underwriter through the Representatives specifically for inclusion in the Registration Statement or any amendment thereto, Time of Sale Information or in the Prospectus or any amendment or supplement thereto. This indemnity agreement will be in addition to any liability which such Underwriter may otherwise have. The Company acknowledges that the statements set forth in                   in the Time of Sale Information and Prospectus constitute the only information furnished in writing by or on behalf of the Underwriters for inclusion in the Prospectus (or any amendment or supplement thereto);

(c)Promptly after receipt by an indemnified party under this Section 9 of notice of the commencement of any action, such indemnified party will, if a claim in respect thereof is to be made against the indemnifying party under this Section 9, notify the indemnifying party in writing of the commencement thereof; but the failure so to notify the indemnifying party (i) will not relieve the indemnifying party from liability under paragraph (a) or (b) above unless and to the extent it did not otherwise learn of such action and such failure results in the forfeiture by the indemnifying party of substantial rights and defenses; and (ii) will not, in any event, relieve the indemnifying party from any obligations to any indemnified party other than the indemnification obligation provided in paragraph (a) or (b) above. The indemnifying party shall be entitled to appoint counsel of the indemnifying party’s choice at the indemnifying party’s expense to represent the indemnified party in any action for which indemnification is sought (in which case

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the indemnifying party shall not thereafter be responsible for the fees and expenses of any separate counsel retained by the indemnified party or parties except as set forth below); provided, however, that such counsel shall be reasonably satisfactory to the indemnified party. Notwithstanding the indemnifying party’s election to appoint counsel to represent the indemnified party in an action, the indemnified party shall have the right to employ separate counsel (including local counsel), and the indemnifying party shall bear the reasonable fees, costs and expenses of such separate counsel if (i) the use of counsel chosen by the indemnifying party to represent the indemnified party would present such counsel with a conflict of interest; (ii) the actual or potential defendants in, or targets of, any such action include both the indemnified party and the indemnifying party and the indemnified party shall have reasonably concluded that there may be legal defenses available to it and/or other indemnified parties which are different from or additional to those available to the indemnifying party; (iii) the indemnifying party shall not have employed counsel satisfactory to the indemnified party to represent the indemnified party within a reasonable time after notice of the institution of such action; or (iv) the indemnifying party shall authorize the indemnified party to employ separate counsel at the expense of the indemnifying party; it being understood, however, that in each case the indemnifying party shall not, in connection with any one such action or separate but substantially similar or related actions in the same jurisdiction arising out of the same general allegations or circumstances, be liable for the reasonable fees and expenses of more than one separate firm of attorneys (in addition to any local counsel) at any time for all such indemnified parties, which firm shall be designated by the Representatives if the indemnified parties consist of the Underwriters or their directors, members, officers, employees or agents. An indemnifying party will not, without the prior written consent of the indemnified parties, settle or compromise or consent to the entry of any judgment with respect to any pending or threatened claim, action, suit or proceeding in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified parties are actual or potential parties to such claim or action) unless such settlement, compromise or consent includes an unconditional release of each indemnified party from all liability arising out of such claim, action, suit or proceeding;

(d)In the event that the indemnity provided in paragraph (a) or (b) of this Section 9 is for any reason held to be unenforceable by an indemnified party although applicable in accordance with its terms, the Company and the Underwriters agree to contribute to the aggregate losses, claims, damages and liabilities (including legal or other expenses reasonably incurred in connection with investigating or defending same) (collectively, “Losses”) to which the Company and one or more of the Underwriters may be subject in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand and by the Underwriters on the other from the offering of the Bonds; provided, however, that in no case shall any Underwriter (except as may be provided in any agreement among the Underwriters relating to the offering of the Bonds) be responsible for any amount in excess of the purchase discount or commission applicable to the Bonds purchased by such Underwriter hereunder; provided, further, that each Underwriter’s obligation to contribute to Losses hereunder shall be several and not joint. If the allocation provided by the immediately preceding sentence is unavailable for any reason, the Company and the Underwriters shall contribute in such proportion as is appropriate to reflect not only such relative benefits but also the relative fault of the Company on the one hand and of the Underwriters on the other in connection with the statements or omissions which resulted in such Losses, as well as any other relevant equitable considerations. Benefits received by the Company shall be deemed to be equal to the total net proceeds from the offering (before deducting expenses) received by it, and benefits received by the Underwriters shall be deemed to be equal to the total underwriting discounts and commissions in each case set forth on the cover of the Prospectus Supplement. Relative fault shall be determined by reference to, among other things, whether any untrue or any alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information provided by the Company on the one hand or the Underwriters on the other, the intent of the parties and their relative knowledge, information and opportunity to correct or prevent such untrue statement or omission. The Company and the Underwriters agree that it would not be just and equitable if contribution were determined by pro rata allocation or any other method of allocation which does not take account of the equitable

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considerations referred to above. Notwithstanding the provisions of this paragraph (d), no person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. For purposes of this Section 9, each person who controls an Underwriter within the meaning of either the Act or the Exchange Act and each director, member, officer, employee and agent of an Underwriter shall have the same rights to contribution as such Underwriter, and each person who controls the Company within the meaning of either the Act or the Exchange Act and each officer, director, member, employee or agent of the Company shall have the same rights to contribution as the Company, subject in each case to the applicable terms and conditions of this paragraph (d).

10. Default by an Underwriter. If any one or more Underwriters shall fail to purchase and pay for any of the Bonds agreed to be purchased by such Underwriter hereunder and such failure to purchase shall constitute a default in the performance of its or their obligations under this Agreement, the remaining Underwriters shall be obligated severally to take up and pay for (in the respective proportions which the principal amount of Bonds set forth opposite their names in Schedule I hereto bear to the aggregate principal amount of Bonds set forth opposite the names of all the remaining Underwriters) the Bonds which the defaulting Underwriter or Underwriters agreed but failed to purchase; provided, however, that in the event that the aggregate principal amount of Bonds which the defaulting Underwriter or Underwriters agreed but failed to purchase shall exceed 10% of the aggregate amount of Bonds set forth in Schedule I hereto, the remaining Underwriters shall have the right to purchase all, but shall not be under any obligation to purchase any, of the Bonds, and if such nondefaulting Underwriters do not purchase all the Bonds, this Agreement will terminate without liability to any nondefaulting Underwriter or the Company. In the event of a default by any Underwriter as set forth in this Section 10, the Closing Date may be postponed for such period, not exceeding five Business Days, as the Representatives shall determine in order to effect whatever changes may thereby be made necessary in the Registration Statement or the Prospectus or any amendment or supplement to either thereof, or in any other documents or arrangements, and the Company agrees to file promptly any amendments or supplements to the Registration Statement or the Prospectus which in the opinion of the Representatives may thereby be made necessary. It is understood that any such postponement, change, amendment and/or supplement may require the establishment of a new “time of sale” and new “time of sale information”. The term “Underwriter” as used in this Agreement shall include any person substituted under this Section with like effect as if such person had originally been a party to this Agreement. Nothing contained in this Agreement shall relieve any defaulting Underwriter of its liability, if any, to the Company or any nondefaulting Underwriter for damages occasioned by its default hereunder.

11. Termination. This Agreement shall be subject to termination in the absolute discretion of the Representatives, by notice given to the Company prior to delivery of and payment for the Bonds, if at any time after the date hereof and prior to the delivery of and payment for the Bonds (i) trading in the common stock of Xcel Energy Inc. shall have been suspended by the Commission or the New York Stock Exchange or trading in securities generally on the New York Stock Exchange shall have been suspended or limited or minimum prices shall have been established on such Exchange; (ii) a banking moratorium shall have been declared either by Federal or New York State authorities; (iii) there shall have occurred a material disruption in commercial banking or securities settlement or clearance services in the United States or Europe; or (iv) there shall have occurred any outbreak or escalation of hostilities, declaration by the United States of a national emergency or war or other calamity or crisis the effect of which on financial markets is such as to make it, in the sole judgment of the Representatives, impracticable or inadvisable to proceed with the offering or delivery of the Bonds as contemplated by the Time of Sale Information and Prospectus.

12. Indemnities to Survive Delivery. The respective agreements, representations, warranties, indemnities and other statements of the Company or its officers and of the Underwriters set forth in or made pursuant to this Agreement will remain in full force and effect, regardless of any investigation made by or on behalf of any Underwriter or the Company or any of their respective officers, directors or controlling persons within the meaning of the Act, and will survive delivery of and payment for the Bonds. The provisions of Sections 8 and 9 hereof shall survive the termination or cancellation of this Agreement.

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13. Notices. All communications hereunder will be in writing and, if sent to the Representatives, will be mailed, delivered or transmitted and confirmed to them at their address set forth for that purpose in Schedule I hereto or, if sent to the Company, will be mailed, delivered or transmitted and confirmed to it at                                       , attention Secretary. All communications shall take effect at the time of receipt thereof.

14. Successors. This Agreement will inure to the benefit of and be binding upon the parties hereto and their respective successors and the officers and directors and controlling persons referred to in Section 9 hereof, and no other person will have any right or obligation hereunder.

15. Applicable Law. This Agreement will be governed by and construed in accordance with the laws of the State of New York applicable to contracts made and to be performed within the State of New York.

16. Counterparts. This Agreement may be executed in one or more counterparts, each of which shall constitute an original and all of which together shall constitute one and the same instrument.

17. Headings. The section headings used herein are for convenience only and shall not affect the construction hereof.

18. Other. As used herein, “Business Day” shall mean any day other than a Saturday, a Sunday or a legal holiday or a day on which banking institutions or trust companies are authorized or obligated by law to close in the City of New York.

19. Underwriters Counsel. The Company and the Underwriters acknowledge that Dewey Ballantine LLP (a) is acting as counsel to the Underwriters in connection with this Agreement and the transactions contemplated hereby and (b) has acted, and may continue to act, as counsel to the Company’s parent company, Xcel Energy Inc., and certain of its subsidiaries in connection with certain regulatory matters, and the Company and the Underwriters consent to such representation.

[signature page follows]

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If the foregoing is in accordance with your understanding of our agreement, please sign and return to us the enclosed duplicate hereof, whereupon this letter and your acceptance shall represent a binding agreement among the Company and the several Underwriters.

		Very truly yours,
		PUBLIC SERVICE COMPANY OF COLORADO
		By
		[title]
The foregoing Agreement is hereby confirmed
and accepted as of the date first above written.
[NAME OF REPRESENTATIVE]
By
	For itself or themselves and as Representatives of the several Underwriters, if any, named in Schedule II to the foregoing Agreement.

SCHEDULE I

Underwriting Agreement dated

Registration Statement No. 333-

Representatives and Addresses:

Bonds:

Designation:
Principal Amount: $
Supplemental Indenture dated as of
Date of Maturity:
Interest Rate:	% per annum, payable                   and                  of each year,
	commencing
Purchase Price:	% of the principal amount thereof, plus accrued interest
	from                   to the date of payment and delivery.
Public Offering
Price:	% of the principal amount thereof, plus accrued interest
	from                          to the date of payment and delivery.
Redemption
Provisions:

Closing Date and Location:

Office for Delivery of Bonds:

Office for Payment of Bonds:

Office for Checking of Bonds:

SCHEDULE II

Name	Amount
Total	$

SCHEDULE III

PRICING INFORMATION

(To Prospectus Supplement dated           )

PUBLIC SERVICE COMPANY OF COLORADO

$              ,       % First Mortgage Bonds, Series No.      due           

Issuer:	Public Service Company of Colorado
Size:	$
Maturity:	, 20
Coupon:	%
Price:	% of face amount
Interest Payment Dates:	and                  , commencing
Redemption Provisions:
[First call date:	]
Redemption prices:
Settlement:	T |        ;            , 200
[CUSIP:	]
[Ratings	]
[Other Underwriters]
Note:  A securities rating is not a recommendation to buy, sell or hold securities and may be subject to revision or withdrawal at any time.

The issuer has filed a registration statement (including a prospectus) with the SEC for the offering to which this communication relates. Before you invest, you should read the prospectus in that registration statement and other documents the issuer has filed with the SEC for more complete information about the issuer and this offering. You may get these documents for free by visiting EDGAR on the SEC website at www.sec.gov. Alternatively, the issuer, any underwriter or any dealer participating in the offering will arrange to send you the prospectus if you request it by calling collect at                  .

SCHEDULE IV

Time of Sale Information

Preliminary Prospectus dated

Pricing Information as set forth in Schedule III

EXHIBIT A

FORM OF OPINION OF PAULA M. CONNELLY

For the purpose of rendering this opinion, I have examined the proceedings taken by Public Service Company of Colorado, a Colorado corporation (the “Company”), with respect to the issue and sale by the Company of $                   principal amount of $                First Mortgage Bonds, Series No.       due          (the “Bonds”).  In connection therewith I have participated in the preparation of the proceedings for the issuance and sale of the Bonds including the Underwriting Agreement dated                       , between you and the Company relating to your purchase of the Bonds (the “Agreement”), and have either participated in the preparation of or examined the Trust Indenture dated October 1, 1993, from the Company to U.S. Bank Trust National Association, as successor trustee (the “Trustee”), as heretofore supplemented and as it will be further supplemented by Supplemental Indenture No.        creating the Bonds (said indenture, as so supplemented and to be further supplemented, being hereafter referred to as the “Indenture”).  This letter is furnished to the Underwriters pursuant to Section 6(b) of the Agreement.  Except as otherwise defined herein, terms used in this letter that are defined in the Agreement are used herein as so defined.  I also have participated in the preparation of or examined the registration statement and any amendments thereto and the accompanying prospectuses and any amendments or supplements thereto, as filed under the Act, with respect to the Bonds.  My examination has extended to all statutes, records, instruments, and documents which I have deemed necessary to examine for the purposes of this opinion.

I am of the opinion that:

1.             The Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the State of Colorado with corporate power and authority to own, lease and operate its properties and conduct its business as described in the Prospectus and to enter into and perform its obligations under the Agreement;

2.             The Agreement has been duly authorized, executed and delivered by the Company;

3.             The issuance and sale of the Bonds, have been duly authorized and approved by an order of The Public Utilities Commission of the State of Colorado and such order is final and in full force and effect on the date hereof, the time for appeal therefrom or review thereof or intervention with respect thereto having expired; no further approval, authorization, consent or other order of any public board or body in the State of Colorado is legally required in connection with the transactions contemplated by the Agreement or Indenture, except as may be required under the blue sky laws of any jurisdiction in connection with the purchase and distribution of the Bonds by the Underwriters in the manner contemplated by the Agreement and in the Prospectus;

4.             Neither the execution and delivery of the Agreement, the issue and sale of the Bonds, nor the consummation of any other of the transactions therein contemplated, nor the fulfillment of the terms thereof will conflict with, result in a breach or violation or imposition of any lien, charge or encumbrance upon any property or assets of the Company or any of its subsidiaries, other than the security interest created by the Bonds and the Indenture under (i) the Restated Articles of Incorporation, as amended, or By-Laws of the Company or any of its subsidiaries; (ii) the terms of any indenture, contract, lease, mortgage, deed of trust, note agreement, loan agreement or other agreement, obligation, condition, covenant or instrument to which the Company or any of its subsidiaries is a party or bound or to which its or their property is subject; or (iii) any statute, law, rule, regulation, judgment, order or decree applicable to the Company or any of its subsidiaries of any court, regulatory body, administrative agency, governmental body, arbitrator or other authority having jurisdiction over the Company or any of its subsidiaries or any of its or their properties except, in the case of clause (ii) or (iii), any such conflict, breach or violation, if it did exist, would not, individually or in the aggregate, have a material adverse change in the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries taken as a whole, whether or not arising from transactions in the ordinary course of business;

5.             The facsimile signature of a Senior Vice President or Vice President of the Company in lieu of his manual signature on the Bonds and the facsimile signature of the Secretary or an Assistant Secretary of the Company attesting the corporate seal in lieu of his manual signature on the Bonds have been duly and properly authorized by the Board of Directors of the Company, are not inconsistent with the provisions of the Restated

Articles of Incorporation, as amended, or By-Laws of the Company and are valid and effective under the laws of the State of Colorado; and the facsimile signatures of such officers on the Bonds have the same legal effect as though they had manually signed and attested the Bonds as such respective officers;

6.             The descriptions in the Registration Statement, Time of Sale Information and Prospectus of Colorado state statutes and legal and governmental proceedings are accurate in all material respects; to the best of my knowledge, there are no franchises, contracts, indentures, mortgages, loan agreements, notes, leases or other instruments that would be required to be described in the documents incorporated by reference in the Prospectus that are not described or referred to in such incorporated documents, and the descriptions thereof or references thereto are correct in all material respects;

7.             There is no pending, or to my knowledge, threatened suit or proceeding before any court or governmental agency, authority or body or any arbitration involving the Company or any of its subsidiaries required to be disclosed in the Prospectus which is not adequately disclosed in the Prospectus; and

8.             The franchises held by the Company, together with the applicable Certificates of Convenience and Necessity issued by The Public Utilities Commission of the State of Colorado, give the Company all necessary authority for the maintenance and operation of its properties and business as now conducted, and are free from burdensome restrictions or conditions of an unusual character.

In the course of my participation in the preparation or examination of the Registration Statement and any amendments thereto, the Time of Sale Information and the Prospectus and any amendments or supplements thereto, I made investigations as to the accuracy of certain of the statements of fact contained therein, I discussed other matters with officers, employees, and representatives of the Company, and I examined various corporate records and data. While I do not pass upon or assume responsibility for, and shall not be deemed to have independently verified, the accuracy and completeness of the statements contained in the Registration Statement or the Prospectus (except as to matters set forth in paragraphs 11 and 12 above), nothing has come to my attention that would lead me to believe that the Registration Statement, at the time it became effective, contained an untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary in order to make the statements therein, not misleading, that the Time of Sale Information, as of                      , included any untrue statement of a material fact or omitted to state a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading, or that the Prospectus, at the time it was filed with the Commission pursuant to Rule 424(b) under the Act and at the date hereof, contained or contains an untrue statement of material fact or omitted or omits to state a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading.

My opinions herein are limited to the laws of the State of Colorado.  This letter speaks as of the date hereof and I undertake no responsibility to advise you of any change in circumstances after the date hereof.

This letter is not being delivered for the benefit of, nor may it be relied upon by, the holders of the Bonds or any other party to which it is not specifically addressed or to which reliance has not expressly been permitted hereby. This letter may be relied upon only by the addressees hereof in connection with the issuance and sale of the Bonds and may not be relied upon for any other purpose.

For purposes of rendering their opinion of even date herewith to the Underwriters, Dewey Ballantine LLP are entitled to rely on my opinions in paragraphs 1, 2 and 3, above as to all matters of Colorado law as if such opinions were addressed to them.

Respectfully submitted,

By:

Paula M. Connelly

Assistant General Counsel

Xcel Energy Services, Inc.

EXHIBIT B

FORM OF OPINION OF LEBOEUF, LAMB, GREENE & MACRAE LLP

Ladies and Gentlemen:

We have acted as counsel to Public Service Company of Colorado (the “Company”) with respect to matters relating to the Indenture dated as of October 1, 1993, as amended and supplemented (the “Indenture”), between the Company and U.S. Bank Trust National Association (formerly First Trust of New York, National Association), as successor trustee (the “Trustee”), in connection with the sale by the Company of up to $                      aggregate principal amount of its First Mortgage Bonds, Series No.       due        (the “Bonds”) under such Indenture.  This opinion is being delivered pursuant to Section 6(b) of the Purchase Agreement, dated                        (the “Agreement”), between the Company and you as representatives of the Underwriters (the “Underwriters”).  Unless otherwise stated, defined terms used herein shall have the respective meanings given to them in the Agreement.

We are not general counsel to the Company and our representation of the Company consists of advising it with respect to corporate matters as to which we have been specifically consulted.  We are familiar with the legal matters pertaining to, and the corporate proceedings of the Company taken with respect to, the authorization and the issuance and sale by the Company of the Bonds.  We have examined, among other things, the Prospectus and any amendment and supplement thereto, the corporate records of the Company, the Indenture (including the Supplemental Indenture creating the Bonds), and such other proceedings, papers and documents as we have deemed relevant for the purposes of rendering the opinions enumerated below.  In such examination, we have assumed the genuineness of all signatures, the authenticity of all documents submitted to us as originals, the conformity to original documents of all documents submitted to us as copies and the authenticity of all such latter documents.  We have also assumed the regularity of all corporate proceedings.  We have relied as to various questions of fact upon discussions with officers and representatives of the Company and the representations and warranties of the Company contained in the Agreement and upon the certificates of public officials and of officers of the Company being delivered to you thereunder.

On the basis of and subject to the foregoing, and subject to the further limitations and qualifications set forth below, it is our opinion that:

1.             The Indenture has been duly and validly authorized, executed and delivered by the Company, is in due and proper form and (assuming the Indenture has been duly authorized, executed and delivered by the Trustee) constitutes a legal, valid and binding mortgage of the Company under Colorado law, enforceable in accordance with its terms, subject to bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance and transfer, and other similar laws affecting the rights of mortgagees and creditors generally, state laws that affect the enforcement of certain remedial provisions of the Indenture, and general principles of equity (regardless of whether such principles are considered in a proceeding at law or in equity); provided, however, that such state laws that affect the enforcement of certain remedial provisions of the Indenture will not, in our opinion, render the remedies afforded by the Indenture inadequate for the practical realization of the benefit of the security provided thereby;

2.             The Bonds are in due and proper form and the issuance and sale of the Bonds have been duly authorized by all necessary corporate action, and when duly executed, authenticated and delivered to the Underwriters pursuant to the Agreement against payment of the consideration set forth therein, the Bonds will be legal, valid and binding obligations of the Company enforceable (subject to the exceptions and limitations referred to in paragraph 1 hereof) in accordance with their terms and entitled to the benefits and security of the Indenture; and the Bonds will be secured equally and ratably with all other bonds outstanding under the Indenture; and

3.             The Bonds and the Indenture conform as to legal matters to the descriptions of the terms thereof contained in the Prospectus under the captions “Supplemental Description of the First Mortgage” and “Description of the First Mortgage Bonds”.

This opinion is limited to the laws of the State of New York, the State of Colorado and the federal law of the United States of America.  This opinion speaks as of the date hereof and we undertake no responsibility to advise you of any change in circumstances after the date hereof.

Dewey Ballantine LLP is hereby authorized to rely upon this opinion as to matters governed by the law of the State of Colorado as if this letter were addressed to them.  This letter is not being delivered for the benefit of, nor may it be relied upon by, the holders of the Bonds or any other party to which it is not specifically addressed or to which reliance has not expressly been permitted hereby.  This letter may be relied upon only by such persons only of in connection with the issuance and sale of the Bonds and may not be relied upon for any other purpose.

Very truly yours,

EXHIBIT C

FORM OF OPINION OF RYLEY CARLOCK & APPLEWHITE

Ladies and Gentlemen:

We have acted as counsel to Public Service Company of Colorado (the “Company”), with respect to matters relating to the Indenture dated as of October 1, 1993, as amended and supplemented (the “Indenture”), between the Company and U.S. Bank Trust National Association  as successor trustee (the “Trustee”) in connection with the sale by the Company of up to $          aggregate principal amount of its First Mortgage Bonds, Series No.      due         (the “Bonds”).  This opinion is being delivered pursuant to Section 6(b) of the Underwriting Agreement, dated                      (the “Agreement”), between the Company and you as  representatives of the Underwriters (the “Representatives”).  Unless otherwise stated, defined terms used herein shall have the respective meanings given to them in the Agreement.

We are not general counsel to the Company and our representation of the Company consists of advising it with respect to [corporate] matters as to which we have been specifically consulted.  We have relied as to various questions of fact upon discussions with officers and representatives of the Company and the representations and warranties of the Company contained in the Agreement and upon the certificates of public officials and of officers of the Company being delivered to you thereunder. We have also relied upon information obtained from public records and from the Company.

We are of the opinion that:

1.             The Company has good title to the real properties specifically or generally described or referred to in the Indenture as subject to the lien thereof (except such real property as may have been sold, exchanged or otherwise disposed of), subject only to in the case of such properties which are used or to be used in or in connection with the Electric Utility Business (as defined in the Indenture) (whether or not such use is the sole use of such property), the lien of the Indenture and Permitted Liens (as defined in the Indenture); and

2.             The Indenture and the filings and recordations made in connection therewith constitute a mortgage lien on the properties specifically or generally described or referred to therein as subject to the lien thereof (except such properties as may have been sold, exchanged or otherwise disposed of or released from the lien thereof in accordance with the terms thereof), subject to no liens prior to the lien of the Indenture other than Permitted Liens; and the Indenture by its terms effectively subjects to the lien thereof all property (except property of the kinds specifically excepted from the lien of the Indenture by the terms thereof) acquired by the Company after the date of execution and delivery of the Indenture and used or to be used in or in connection with the Electric Utility Business, subject to Permitted Liens, any lien thereon existing at the time of such acquisition and to any liens for unpaid portions of the purchase money placed thereon at the time of such acquisition, and also subject to the provisions of Article Thirteen of the Indenture and to certain possible claims of a trustee in bankruptcy and possible claims and taxes of the federal government.

Our opinions herein are limited to the laws of the State of Colorado.  This opinion speaks as of the date hereof and we undertake no responsibility to advise you of any change in circumstances after the date hereof.

This letter is not being delivered for the benefit of, nor may it be relied upon by, the holders of the Bonds or any other party to which it is not specifically addressed or to which reliance has not expressly been permitted hereby. This letter may be relied upon only by the addressees hereof in connection with the issuance and sale of the Bonds and may not be relied upon for any other purpose.

Very truly yours,

EXHIBIT D

FORM OF OPINION OF JONES DAY

[Insert Underwriters]

Ladies and Gentlemen:

We have acted as special counsel to Public Service Company of Colorado, a Colorado Corporation (the “Company”), in connection with the purchase from the Company by the Underwriters named in Schedule II to the Underwriting Agreement, dated              (the “Underwriting Agreement”), by and between the Company and you, as Representatives of the several Underwriters named on Schedule II thereto (the “Underwriters”), of $          aggregate principal amount of First Mortgage Bonds (the “Bonds”), being issued on this date under the Company’s Indenture, dated as of October 1, 1993, as heretofore supplemented and as it is being further supplemented by a supplemental indenture creating the Bonds (said Indenture, as so supplemented, being hereafter referred to as the “Indenture”).  This opinion is furnished to the Representatives, as representatives for the Underwriters pursuant to Section 6(b) of the Underwriting Agreement. Terms used in this opinion that are defined in the Underwriting Agreement are used as so defined.

In connection with the opinions and views expressed herein, we have examined such documents, records and matters of law as we have deemed relevant or necessary for purposes of this opinion. Based upon the foregoing and subject to the further assumptions, qualifications and limitations stated herein, we are of the opinion that:

1.             Assuming that the Underwriting Agreement has been duly (a) authorized by the Company and (b) executed and delivered by the Company under Colorado law, the Underwriting Agreement has been duly executed and delivered by the Company to the extent such execution and delivery are matters of New York law.

2.             Assuming that (a) the Company is a corporation existing and in good standing under the laws of the State of Colorado and (b) the Indenture (i) has been (A) authorized by all necessary corporate action of the Company and (B) executed and delivered by the Company under the laws of the State of Colorado, (ii) does not violate the laws of the State of Colorado, (iii) constitutes the valid and binding obligation of the Company under the laws of the State of Colorado, and (iv) constitutes a legal, valid and binding mortgage of the Company under Colorado law, the Indenture constitutes a valid and binding obligation of the Company under New York law, enforceable against the Company in accordance with its terms.

3.             Assuming that (a) the Company is a corporation existing and in good standing under the laws of the State of Colorado and (b) the Bonds (i) have been (A) authorized by all necessary corporate action of the Company and (B) validly issued, executed and delivered by the Company under the laws of the State of Colorado, (ii) do not violate the laws of the State of Colorado, and (iii) constitute valid and binding obligations of the Company under the laws of the State of Colorado, the Bonds, when authenticated by the Trustee in accordance with the terms of the Indenture and delivered against payment therefor in accordance with the terms of the Underwriting Agreement, will constitute valid and binding obligations of the Company under New York law, enforceable against the Company in accordance with their terms.

4.             Assuming that the issuance and sale of the Bonds have been duly authorized and approved by an order of Public Utilities Commission of the State of Colorado and such order is final and in full force and effect on the date hereof, no consent, approval, authorization or order of, or filing with, any governmental agency or body or any court of the United States or the State of Colorado is required in connection with the issuance or sale of the Bonds by the Company to the Underwriters, except as may be required under (i) state securities or blue sky laws or (ii) the Securities Act of 1933 (the “Securities Act”), the Securities Exchange Act of 1934 or the Trust Indenture Act of 1939.

5.             The (i) execution, delivery and performance of (A) the Indenture by the Company and (B) the Underwriting Agreement by the Company, (ii) issuance and sale of the Bonds by the Company and (iii) compliance with the terms and provisions thereof by the Company will not violate any U.S. federal securities or State of New

York law or regulation known to us to be generally applicable to transactions of this type, or any order or decree of any U.S. federal securities or State of New York court, arbitrator or governmental agency that is binding upon the Company or its property or any agreement to which the Company is a party or bound (this opinion being limited (i) to those orders and decrees identified on Exhibit A attached hereto and to those agreements identified on Exhibit B attached hereto, and (ii) in that we express no opinion with respect to any violation (a) not readily ascertainable from the face of any such order, decree or agreement, (b) arising under or based upon any cross default provision insofar as it relates to a default under an agreement not identified on Exhibit B attached hereto, or (c) arising as a result of any violation of any agreement or covenant by failure to comply with any financial or numerical requirement requiring computation).

6.             The Company is not required to register as an “investment company,” as such term is defined in the Investment Company Act of 1940.

7.             The statements contained in the Prospectus under the captions “Description of First Mortgage Bonds” and “Supplemental Description of The First Mortgage Bonds,” insofar as such statements purport to summarize legal matters or provisions of documents referred to therein, present fair summaries of such legal matters and documents.

We have participated in the preparation of the Company’s registration statement on Form S-3 (Registration No.                  ) (the “Registration Statement”), the prospectus, dated                  (the “Base Prospectus”), the preliminary prospectus supplement, dated                    (together with the Base Prospectus, the “Preliminary Prospectus”), the information identified on Schedule I hereto (together with the Preliminary Prospectus, the “Time of Sale Information”) and the prospectus supplement, dated                       (together with the Base Prospectus, the “Prospectus”).  From time to time, we have had discussions with certain officers, directors and employees of the Company, with representatives of Deloitte & Touche LLP, the independent registered public accounting firm who examined the financial statements of the Company included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus, with the Underwriters and with counsel to the Underwriters concerning the information contained in or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus and the proposed responses to various items in Form S-3.  Based upon our participation and discussions described above, we are of the view that the Registration Statement (including all information deemed to be part of and included therein pursuant to Rule 430B under the Securities Act), as of                        , which is the date you have identified as the earlier of the date the Prospectus was first used or the date of the first contract of sale of any Bonds (such date, the “Effective Date”), and the Prospectus, as of the Effective Date, complied as to form in all material respects to the requirements of the Securities Act and the rules and regulations of the Securities and Exchange Commission (the “Commission”) thereunder, except that we express no view with respect to (i) the financial statements, financial schedules and other financial and statistical data included or incorporated by reference therein or (ii) the information referred to under the caption “Experts” as having been included or incorporated by reference therein on the authority of Deloitte & Touche LLP as experts.

We have not independently verified and are not passing upon, and do not assume any responsibility for, the accuracy, completeness or fairness (except as and to the extent set forth in paragraph 7 above) of the information included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus.  Based upon our participation and discussions set forth above, however, no facts have come to our attention that cause us to believe that the Registration Statement (including all information deemed to be part of and included therein pursuant to Rule 430B under the Securities Act), as of the Effective Date, contained any untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary to make the statements therein not misleading, that the Time of Sale Information, as of              p.m. on                   (which is the time that you have informed us was prior to the first contract of sale of any Bonds by the Underwriters), included any untrue statement of a material fact or omitted to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading, or that the Prospectus, as of the Effective Date or on the date hereof, included or includes any untrue statement of a material fact or omitted or omits to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading, except that we express no view with respect to (i) the financial statements, financial schedules and other financial and statistical data included or incorporated by reference therein or (ii) the information referred to under the caption “Experts” as having been included or incorporated by reference therein on the authority of Deloitte & Touche LLP as experts.

The Registration Statement has become effective under the Securities Act, and no stop order suspending the effectiveness of the Registration Statement has been issued and no proceedings for that purpose are pending or threatened by the Commission.

The opinions and views set forth above are subject to the following limitations, qualifications and assumptions:

We have assumed, for purposes of the opinions and views expressed herein, the legal capacity of all natural persons executing documents, the genuineness of all signatures, the authenticity of original and certified documents and the conformity to original or certified copies of all copies submitted to us as conformed or reproduction copies.  For the purposes of the opinions and views expressed herein, we also have assumed that the Trustee has authorized, executed, authenticated and delivered the documents or securities to which it is a party and that each of such documents or securities is the valid, binding and enforceable obligation of the Trustee.

As to facts material to the opinions and assumptions expressed herein, we have, with your consent, relied upon oral or written statements and representations of officers and other representatives of the Company and others, including the representations and warranties of the Company contained in the Underwriting Agreement.  We have not independently verified such matters.

Our opinions set forth in paragraphs 2 and 3 above with respect to the enforceability of the documents or securities referred to in such opinions are subject to: (i) bankruptcy, insolvency, reorganization, fraudulent transfer and fraudulent conveyance, voidable preference, moratorium or other similar laws, and related regulations and judicial doctrines from time to time in effect relating to or affecting creditors’ rights and remedies generally; (ii) general equitable principles, whether such principles are considered in a proceeding at law or in equity; (iii) the qualification that we express no opinion as to the validity, binding effect or enforceability of any provision in any document (A) relating to indemnification, contribution or exculpation in connection with violations of any securities laws or statutory duties or public policy, or in connection with willful, reckless or unlawful acts or gross negligence of the indemnified or exculpated party or the party receiving contribution, (B) relating to forum selection to the extent the forum is a federal court, (C) relating to forum selection to the extent that any relevant action or proceeding does not arise out of or relate to such document or to the extent that the enforceability of any such provision is to be determined by any court other than a court of the State of New York, (D) relating to choice of governing law to the extent that the enforceability of any such provision is to be determined by any court other than a court of the State of New York or may be subject to constitutional limitations or (E) specifying that provisions thereof may be waived only in writing, to the extent that an oral agreement or an implied agreement by trade practice or course of conduct has been created that modifies any provision of such documents; and (iv) the effect of applicable rules of law that (A) provide that forum selection clauses in contracts are not necessarily binding on the court in the forum selected, (B) may, where less than all of a contract may be unenforceable, limit the enforceability of the balance of the contract to circumstances in which the unenforceable portion is not an essential part of the agreed exchange, or that permit a court to reserve to itself a decision as to whether any provision of any agreement is severable, and (C) govern and afford judicial discretion regarding the determination of damages and entitlement to attorneys’ fees and other costs.

With respect to our opinions in paragraph 5, we express no opinion as to state securities or “blue sky” laws.

The statement above with respect to the effectiveness of the Registration Statement under the Securities Act is based solely on the Notice of Effectiveness relating to the Registration Statement as published by the Commission on its Web site on                    .  In addition, the statement above with respect to no stop order suspending the effectiveness of the Registration Statement having been issued and no proceedings for that purpose being pending or threatened by the Commission are based solely on telephone conversations involving lawyers in our firm actively engaged in our representation of the Company in this matter and members of the staff of the Commission, and such statement is made as of the time of such conversations.

The opinions and views expressed herein are limited to (i) the federal laws of the United States of America and (ii) the laws of the State of New York, in each case as currently in effect, and we express no opinion or view as to the effect of the laws of any other jurisdiction on the opinions and views expressed herein.

We express no opinion or view as to the compliance or noncompliance, or the effect of the compliance or noncompliance, of each of the addressees or any other person or entity with any state or federal laws or regulations applicable to each of them by reason of their status as or affiliation with a federally insured depository institution.  Our opinions and views are limited to those expressly set forth herein, and we express no opinions or views by implication.

This letter is furnished by us to you solely for the benefit of the Underwriters and solely with respect to the purchase of the Bonds from the Company by the Underwriters, upon the understanding that we are not hereby assuming any professional responsibility to any other person whatsoever, and that this letter is not to be used, circulated, quoted or otherwise referred to for any other purpose.

Very truly yours,

EX-1.(B)

Exhibit 1(b)

PUBLIC SERVICE COMPANY OF COLORADO
(a Colorado corporation)

FORM OF
UNDERWRITING AGREEMENT

(Senior Debt Securities)

To the Representatives named in Schedule I
hereto of the Underwriters named in
Schedule II hereto

Dear Ladies and Gentlemen:

Public Service Company of Colorado, a Colorado corporation (the “Company”), proposes to sell to the underwriters named in Schedule II hereto (the “Underwriters”), for whom you are acting as representatives (the “Representatives”), its Senior Debt Securities of the designation, with the terms and in the aggregate principal amount specified in Schedule I hereto (the “Debt Securities”) to be issued under its Indenture, dated as of July 1, 1999, from the Company to The Bank of New York, as trustee (the “Trustee”), as previously amended and supplemented and as to be amended and supplemented by a supplemental indenture relating to the Debt Securities (such Indenture as so supplemented and amended being hereinafter referred to as the “Indenture”). If the firm or firms listed in Schedule II hereto include only the firm or firms listed in Schedule I hereto, then the terms “Underwriters” and “Representatives,” as used herein, shall each be deemed to refer to such firm or firms.

1.Representations and Warranties by the Company. The Company represents and warrants to, and agrees with, each Underwriter that:

(a)

(i)The Company meets the requirements for use of Form S-3 under the Securities Act of 1933, as amended (the “Act”) and has filed with the Securities and Exchange Commission (the “Commission”) a registration statement on such Form, including a prospectus, for the registration under the Act of the Debt Securities, which registration statement has become effective. Such registration statement, as amended on the date of such registration statement’s effectiveness for purposes of Section 11 of the 1933 Act, as such Section applies to the Company and the Underwriters for the Debt Securities pursuant to Rule 430B(f)(2) under the 1933 Act (the “Effective Date”) (or upon effectiveness of any post-effective amendment thereto), including the information, if any, deemed pursuant to Rule 430A, 430B or 430C under the Act or under the Securities Exchange Act of 1934 to be part of the registration statement at the time of its effectiveness (“Rule 430 Information”), are collectively referred to herein as the “Registration Statement.”  Each prospectus used before the registration statement became effective, and any prospectus or prospectus supplement that omitted Rule 430 Information that was used after such effectiveness and prior to the execution and delivery of this Agreement is herein called a “preliminary prospectus.”  The preliminary prospectus supplement dated             , including the accompanying prospectus dated         , is herein called the “Preliminary Prospectus.”  The prospectus, in the form first filed under Rule 424(b) under the Act after the date and time this Agreement is executed, is herein called the “Prospectus”;

(ii)The Company will file with the Commission the Prospectus, which will include a prospectus supplement (the “Prospectus Supplement”) relating to the Debt Securities, pursuant to Rule 424 under the Act. Copies of such Registration Statement, the Preliminary Prospectus and Prospectus, any such amendment or supplement and all documents incorporated by reference therein which were filed with the Commission on or prior to the date of this Agreement have been delivered to you and copies of the Prospectus Supplement will be delivered to you promptly after it is filed with the Commission; and

(iii)Unless specifically noted otherwise herein, any reference herein to the Registration Statement, the Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 which were filed under the Securities Exchange Act of 1934, as amended (the “Exchange Act”) as of each effective date for purposes of the Registration Statement or on or before the date hereof for purposes of the Preliminary Prospectus or the Prospectus. If the Company files any document pursuant to the Exchange Act after the date of this Agreement and prior to the termination of the offering of the Debt Securities by the Underwriters, which document is deemed to be incorporated by reference into the Prospectus, the term “Prospectus” shall refer also to said prospectus as supplemented by the document so filed from and after the time said document is filed with the Commission; any reference to any amendment to the Registration Statement shall be deemed to refer to and include (A) any annual report of the Company filed pursuant to Section 13(c) or 15(d) of the Exchange Act after the effective date of the Registration Statement that is incorporated by reference in the Registration Statement and (B) any Prospectus Supplement relating to the Debt Securities. There are no contracts or documents of the Company that are required to be filed as exhibits to the Registration Statement or any documents incorporated by reference therein by the Act, the Exchange Act or the rules and regulations thereunder which have not been so filed.

For purposes of this Agreement, the “Time of Sale” is       :        (New York Time) on the date of this Agreement.

(b)No stop order suspending the effectiveness of the Registration Statement has been issued and no proceeding for that purpose or pursuant to Section 8A of the Act has been initiated or, to the best knowledge of the Company, threatened by the Commission and no order preventing or suspending the use of any preliminary prospectus or the Prospectus has been issued by the Commission;

(c)The Registration Statement, when it became effective, conformed, and any further amendments thereto, when they become effective, will conform, in all material respects to the requirements of the Act and the Trust Indenture Act of 1939, as amended (the “Trust Indenture Act”), and the Prospectus and any amendments or supplements thereto, when filed with the Commission, will conform in all material respects to the requirements of the Act and the Trust Indenture Act;

(d)The Registration Statement, on the Effective Date, did not and any further amendments thereto when they become effective, will not, contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading; as of the Time of Sale, the Preliminary Prospectus and each “free-writing prospectus” (as defined pursuant to Rule 405 under the Act) listed on Schedule IV hereto (collectively, the “Time of Sale Information”) and without regard to any Prospectus Supplement or documents incorporated by reference that were filed after the Time of Sale, did not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements made, in light of the circumstances under which they were made, not misleading; and the Prospectus as of its date and any amendments and supplements thereto, as of the time when they are filed or transmitted for filing with the Commission, and at the Closing Date (as defined below), will not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements made, in light of the circumstances under which they were made, not misleading; provided, however, that the representations and warranties contained in this subsection (d) shall not apply to statements or omissions made in reliance upon and in conformity with information furnished in writing by an Underwriter through the Representatives expressly for use in the Registration Statement, the Time of Sale Information, Prospectus or any amendment or supplement to any thereof;

(e)The documents incorporated by reference in the Registration Statement, the Time of Sale Information or Prospectus, when they were filed with the Commission, and any further documents so filed and incorporated by reference, when they are filed with the Commission or become effective, as the case may be, complied with and will comply in all material respects with the requirements of the Exchange Act or the Act, as the case may be;

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(f)The Company is not, and after giving effect to the offering and sale of the Debt Securities and the application of the proceeds thereof as described in the Prospectus will not be, an “investment company” or an entity “controlled” by an “investment company” within the meaning of the Investment Company Act of 1940, as amended, without taking account of any exemption arising out of the number of holders of the Company’s securities;

(g)The statements in the Prospectus under the headings “Supplemental Description of the Senior Debt Securities” and “Description of the Senior Debt Securities” fairly summarize the matters therein described;

(h)This Agreement has been duly authorized, executed and delivered by the Company;

(i)The Indenture has been duly authorized and the Indenture (excluding the Supplemental Indenture) has been duly executed and delivered by the Company and is in due and proper form and (assuming the Indenture has been duly authorized, executed and delivered by the Trustee) when the Supplemental Indenture is duly executed and delivered the Indenture will constitute a legal, valid and binding obligation of the Company, enforceable in accordance with its terms, except as enforcement thereof may be limited by laws and principles of equity affecting creditors’ rights, including, without limitation, bankruptcy and insolvency laws;

(j)The issuance and sale by the Company of the Debt Securities pursuant to this Agreement have been duly authorized by all necessary corporate action; and, when issued, authenticated and delivered to the Underwriters pursuant to this Agreement against payment of the consideration therefor specified herein, the Debt Securities will be valid and binding obligations of the Company, enforceable in accordance with their terms, except as enforcement thereof may be limited by laws or principles of equity affecting creditors’ rights, including, without limitation, bankruptcy and insolvency laws, and will be entitled to the benefits of the Indenture;

(k)The issuance and sale of the Debt Securities have been duly authorized and approved by an order of the Public Utilities Commission of the State of Colorado and such order is final and in full force and effect on the date hereof, the time for appeal therefrom or review thereof or intervention with respect thereto having expired; no further approval, authorization, consent or other order of any public board or body is legally required in connection with the transactions contemplated by this Agreement and the Indenture, except for the registration under the Act of the Debt Securities and as may be required under the blue sky laws of any jurisdiction in connection with the purchase and distribution of the Debt Securities by the Underwriters in the manner contemplated herein and in the Prospectus;

(l)Neither the execution and delivery of this Agreement or the Supplemental Indenture, the issue and sale of the Debt Securities, nor the consummation of any other of the transactions herein or therein contemplated, nor the fulfillment of the terms hereof or thereof will conflict with, result in a breach or violation or imposition of any lien, charge or encumbrance upon any property or assets of the Company or any of its subsidiaries, other than the liens and security interests created by the Indenture, pursuant to, (i) the charter or by-laws of the Company or any of its subsidiaries; (ii) the terms of any indenture, contract, lease, mortgage, deed of trust, note agreement, loan agreement or other agreement, obligation, condition, covenant or instrument to which the Company or any of its subsidiaries is a party or bound or to which its property is subject; or (iii) any statute, law, rule, regulation, judgment, order or decree applicable to the Company of any court, regulatory body, administrative agency, governmental body, arbitrator or other authority having jurisdiction over the Company or any of its subsidiaries or any of its or their properties except, in the case of clause (ii), any such conflict, default, breach or violation which would not, individually or in the aggregate, have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries taken as a whole, whether or not arising from transactions in the ordinary course of business;

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(m)The Company has good title to the properties specifically or generally described or referred to in the Indenture as subject to the lien thereof (except such property as may have been sold, exchanged or otherwise disposed of) subject only to, in the case of such properties which are used or to be used in or in connection with the Electric Utility Business (as defined in the Indenture dated as of October 1, 1993 from the Company to U.S. Bank Trust National Association, such Indenture, as supplemented the “Mortgage Indenture”) (whether or not such is the sole use of such property), the lien of the Mortgage Indenture and Permitted Liens (as defined in the Mortgage Indenture);

(n)The consolidated historical financial statements and schedules of the Company and its consolidated subsidiaries included or incorporated by reference in the Registration Statement, Time of Sale Information and Prospectus present fairly in all material respects the financial condition, results of operations, cash flows and changes in financial position of the Company as of the dates and for the periods indicated, comply as to form with the applicable accounting requirements of the Act and the Exchange Act and have been prepared in conformity with U.S. generally accepted accounting principles (“GAAP”) throughout the periods involved (except as otherwise noted therein) and comply, and at the Closing Date will comply, in all material respects with the requirements of paragraph (e) of Item 10 of Regulation S-K; the selected financial data set forth under the caption “Selected Consolidated Financial Data” in the Prospectus fairly present, on the basis stated in the Prospectus, the information included therein. Except as disclosed in or incorporated by reference in the Registration Statement, Time of Sale Information and Prospectus, neither the Company nor any of its subsidiaries has any contingent obligations which are material to the Company and its consolidated subsidiaries taken as a whole;

(o)Deloitte & Touche LLP, which audited the financial statements incorporated by reference in the Registration Statement and Prospectus, (i) is an independent registered public accounting firm as required by the Act and the rules and regulations of the Commission thereunder and (ii) is in compliance with its obligations under the Exchange Act with respect to the Company;

(p)The statistical and market-related data and forward-looking statements (within the meaning of Section 27A of the Act and Section 21E of the Exchange Act) included or incorporated by reference in the Time of Sale Information and Prospectus are based on or derived from sources that the Company believes to be reliable and accurate in all material respects and represent good faith estimates that are made on the basis of data derived from such sources;

(q)Except as may otherwise be reflected in or contemplated by the Registration Statement, Time of Sale Information and Prospectus, since the respective dates as of which information is given in the Registration Statement, Time of Sale Information and Prospectus (i) there has been no material adverse change in the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries taken as a whole, whether or not arising from transactions in the ordinary course of business and (ii) neither the Company nor any of its subsidiaries has entered into any transactions which are material to the Company, other than in the ordinary course of business; and, except as so reflected or contemplated, neither the Company nor any of its subsidiaries has any contingent obligations which are material to the Company and its subsidiaries as a whole;

(r)Each of the Company and its subsidiaries has been duly incorporated and is validly existing as a corporation in good standing under the laws of the jurisdiction in which it is chartered or organized with full corporate power and authority to own or lease, as the case may be, and to operate its properties and conduct its business as described in the Registration Statement, Time of Sale Information and Prospectus, and is duly qualified to do business as a foreign corporation and is in good standing under the laws of each jurisdiction in which such qualification is required, whether by reason of the ownership or leasing of property or the conduct of business, except where the failure to be so qualified would not have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its

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subsidiaries taken as a whole, whether or not arising from transactions in the ordinary course of business;

(s)All of the outstanding shares of capital stock of each subsidiary have been duly and validly authorized and issued and are fully paid and nonassessable, and, except as otherwise set forth in the Registration Statement, Time of Sale Information and Prospectus, all outstanding shares of capital stock of the subsidiaries are owned by the Company either directly or through wholly-owned subsidiaries free and clear of any perfected security interest or any other security interests, claims, liens or encumbrances;

(t)The Company has no subsidiaries which would be deemed significant subsidiaries under Regulation S-X;

(u)Neither the Company nor any of its subsidiaries is in conflict, violation, breach or default of (i) any provision of its charter or bylaws; (ii) the terms of any indenture, contract, lease, mortgage, deed of trust, note agreement, loan agreement or other agreement, obligation, condition, covenant or instrument to which it is a party or bound or to which its property is subject; or (iii) any statute, law, rule, regulation, judgment, order or decree applicable to the Company or any of its subsidiaries of any court, regulatory body, administrative agency, governmental body, arbitrator or other authority having jurisdiction over the Company or such subsidiary or any of its properties, as applicable except, in the case of clause (ii) or (iii), any such conflict, violation, breach or default which would not, individually or in the aggregate, (x) have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries taken as a whole, whether or not arising from transactions in the ordinary course of business and (y) impair the validity of the Debt Securities;

(v)No subsidiary of the Company is currently prohibited, directly or indirectly, from paying any dividends to the Company, from making any other distribution on such subsidiary’s capital stock, from repaying to the Company any loans or advances to such subsidiary from the Company or from transferring any of such subsidiary’s property or assets to the Company or any other subsidiary of the Company, except as described in or contemplated by the Registration Statement, Time of Sale Information and Prospectus;

(w)Neither the Company, nor any of its subsidiaries, nor any director, officer, agent, employee or other person or entity acting on behalf of the Company or any of its subsidiaries has, in the course of its actions for, or on behalf of, the Company, used any corporate funds for any unlawful contribution, gift, entertainment or other unlawful expenses relating to political activity; made any direct or indirect unlawful payment to any foreign or domestic government official or employee from corporate funds; or made any unlawful bribe, rebate, payoff, influence payment, kickback or other unlawful payment to any foreign or domestic government official or employee;

(x)(i) the Company has devised and established and maintains the following, among other, internal controls (without duplication): (A) a system of “internal accounting controls” as contemplated in Section 13(b)(2)(B) of the 1934 Act; (B) “disclosure controls and procedures” as such term is defined in Rule 13a-15(e) under the 1934 Act; and (C) “internal control over financing reporting” (as such term is defined in Rule 13a-15(f) under the 1934 Act (the internal controls referred to in clauses (A) and (B) above and this clause (C) being hereinafter called, collectively, the “Internal Controls”); (ii) the Internal Controls are evaluated by the Company’s senior management periodically as appropriate and, in any event, as required by law; and (iii) based on the most recent evaluations of the Internal Controls, (A) the Internal Controls are, individually and in the aggregate, effective in all material respects to perform the functions for which they were established; and (B) all material weaknesses, if any, and significant deficiencies, if any, in the design or operation of the Internal Controls which are reasonably likely to adversely affect the Company’s ability to record, process, summarize and report financial information and any fraud, whether or not material, that involves management or other employees who have a significant role

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in the Internal Controls have been disclosed to the Company’s independent auditors and the audit committee of the Company’s board directors.

(y)Except as set forth in, or incorporated by reference in, the Registration Statement, Time of Sale Information and Prospectus, the Company and its subsidiaries (i) are in compliance with any and all applicable federal, state and local laws and regulations relating to the protection of human health and safety, the environment or hazardous or toxic substances or wastes, pollutants or contaminants (“Environmental Laws”), (ii) have received all permits, licenses or other approvals required of them under applicable Environmental Laws to conduct their respective businesses, (iii) are in compliance with all terms and conditions of any such permits, licenses or approvals, and (iv) have not received notice of any actual or potential liability for the investigation or remediation of any disposal or release of hazardous or toxic substances or wastes, pollutants or contaminants, except where such non-compliance with Environmental Laws, failure to receive required permits, licenses or other approvals, or any such liability would not, individually or in the aggregate, have a material adverse effect on the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business;

(z)With respect to each employee benefit plan (as defined in Section 3(3) of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”)) which the Company or any other organization that together with the Company is treated as a single employer under Sections 414(b), (c), (m) or (o) of the Internal Revenue Code of 1986, as amended (the “Code”) (an “ERISA Affiliate”), has at any time sponsored, maintained, contributed to or been obligated to contribute to (a “Plan”): (i) the Company and each ERISA Affiliate have administered and operated each Plan sponsored or maintained by the Company or an ERISA Affiliate in compliance with ERISA, the Code and other applicable laws except for such instances of noncompliance as have not resulted in and could not reasonably be expected to result in a material liability to the Company or ERISA Affiliate; (ii) each Plan sponsored or maintained by the Company or an ERISA Affiliate intended to qualify under Section 401(a) of the Code so qualifies and to the Company’s knowledge nothing has occurred, whether by action or failure to act, which could reasonably be expected to cause the loss of such qualification of any such Plan; (iii) neither the Company nor any ERISA Affiliate has incurred, and to the Company’s knowledge no event, transaction or condition has occurred or exists under which the Company or any ERISA Affiliate could reasonably expect to incur, any material liability or the imposition of any lien on any of the rights, properties or assets of the Company or any ERISA Affiliate pursuant to Title I or Title IV of ERISA (other than routine claims for benefits) or applicable penalty or excise provisions of the Code; (iv) there has been no reportable event (within the meaning of Section 4043 of ERISA) with respect to any Plan subject to Title IV of ERISA that is sponsored or maintained by the Company or an ERISA Affiliate for which the 30-day reporting requirement has not been waived which could reasonably be expected to result in a material liability under Title IV of ERISA to the Company or an ERISA Affiliate; (v) no accumulated funding deficiency (within the meaning of Section 302 of ERISA and Section 412 of the Code), whether or not waived, exists with respect to any Plan subject to Title IV of ERISA that is sponsored or maintained by the Company; and (vi) neither the Company nor any ERISA Affiliate has incurred, and to the Company’s knowledge no event, transaction or condition has occurred or exists under which the Company or any ERISA Affiliate could reasonably expect to incur, any material liability with respect to termination of, or withdrawal from, any Plan subject to Title IV of ERISA;

(aa)The franchises held by the Company and its subsidiaries, together with the applicable Certificates of Convenience and Necessity issued by the Public Utilities Commission of the State of Colorado, give the Company and such subsidiaries all necessary authority for the maintenance and operation of their respective properties and business as now conducted, and are free from burdensome restrictions or conditions of an unusual character.

(bb)The Company is not an “ineligible issuer” as defined under the Act.

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(cc)The Company is in compliance in all material respects with the Sarbanes-Oxley Act of 2002 and the rules and regulations of the Commission thereunder, to the extent that such Act and such rules are in effect and applicable to the Company.

(dd)The Company has complied and will comply with the requirements of Rule 433 under the Act applicable to any free-writing prospectus, including timely filing with the Commission and legending.

Any certificate signed by any officer of the Company and delivered to the Representatives or counsel for the Representatives in connection with the offering of the Debt Securities shall be deemed a representation and warranty by the Company, as to matters covered thereby, to each Underwriter.

2.Purchase and Sale. Subject to the terms and conditions and in reliance upon the representations and warranties herein set forth, the Company agrees to sell to the Representatives and each other Underwriter, and the Representatives and each other Underwriter agree, severally and not jointly, to purchase from the Company, at the purchase price set forth in Schedule I hereto, the respective principal amounts of the Debt Securities set forth opposite their respective names in Schedule II hereto.

3.Delivery and Payment. Delivery of and payment for the Debt Securities shall be made at the place, date and time specified in Schedule I hereto, which date and time may be postponed by agreement between the Representatives and the Company (such date and time being herein called the “Closing Date”). Delivery of the Debt Securities shall be made to the Representatives for the respective accounts of the several Underwriters against payment by the several Underwriters through the Representatives of the purchase price thereof to or upon the order of the Company by wire transfer payable in same-day funds to the account specified by the Company. The Debt Securities will be delivered in global registered form except that, if for any reason the Company is unable to deliver the Debt Securities in global form, the Company reserves the right, as provided in the Indenture, to make delivery in temporary form. Any Debt Securities delivered in temporary form will be exchangeable without charge for Debt Securities in definitive form. Unless otherwise indicated on Schedule I, the Debt Securities will be registered in the name of Cede & Co., as nominee of The Depository Trust Company and in the principal amounts set forth in Schedule II hereto. The Debt Securities will be made available to the Representatives for checking in New York, New York, not later than 2:00 p.m., New York City time, on the Business Day preceding the Closing Date.

4.Agreements. The Company agrees with the several Underwriters as follows:

(a)The Company shall prepare the Prospectus in a form approved by the Representatives and to file such Prospectus pursuant to Rule 424(b) under the Act not later than the Commission’s close of business on the second Business Day following the execution and delivery of this Agreement; to make no further amendment or any supplement to the Registration Statement or Prospectus prior to the Closing Date which shall be reasonably disapproved by the Representatives promptly after reasonable notice thereof; during the period for which a prospectus is required to be delivered under the Act in connection with the offering and sale of the Debt Securities, to advise the Representatives, promptly after it receives notice thereof, of the time when any amendment to the Registration Statement has been filed or becomes effective or any supplement to the Prospectus or any amended Prospectus has been filed and to furnish the Representatives with copies thereof; to file promptly all reports and any definitive proxy or information statements required to be filed by the Company with the Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the date of the Prospectus and for so long as the delivery of a prospectus is (or in lieu thereof, the Notice referred to in Rule 173(a) under the Act) required under the Act in connection with the offering or sale of the Debt Securities; to make any other required filings pursuant to Rule 433(d)(1) of the Act within the time required by such Rules; to advise the Representatives, promptly after it receives notice thereof, of the issuance by the Commission of any stop order or of any order preventing or suspending the use of any prospectus, of the suspension of the qualification of the Debt Securities for offering or sale in any jurisdiction, of the initiation or threatening of any proceeding for any such purpose, or of any request by the

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Commission for the amending or supplementing of the Registration Statement or the Prospectus or for additional information; to use its best efforts to prevent the issuance of any stop order or of any order preventing or suspending the use of any prospectus or suspending any such qualification, and, in the event of the issuance of any such order, promptly to use its best efforts to obtain the withdrawal of such order;

(b)The Company shall promptly from time to time take such action as the Representatives may reasonably request to qualify the Debt Securities for offering and sale under the securities laws of such jurisdictions as the Representatives may request and to comply with such laws so as to permit the continuance of sales and dealings therein in such jurisdictions for as long as may be necessary to complete the distribution of the Debt Securities, provided that in connection therewith the Company shall not be required to qualify as a foreign corporation or to file a general consent to service of process in any jurisdiction;

(c)The Company shall prior to 10:00 a.m., New York City time, on the            Business Day next succeeding the date of this Agreement and from time to time, furnish the Underwriters with written and electronic copies of the Prospectus in such quantities as the Representatives may from time to time reasonably request, and, if the delivery of a prospectus (or in lieu thereof, the Notice referred to in Rule 173(a) under the Act) is required under the Act at any time in connection with the offering or sale of the Debt Securities and if at any time any event shall have occurred as a result of which the Time of Sale Information or Prospectus as then amended or supplemented conflict with the information contained in the Registration Statement, the Preliminary Prospectus or the Prospectus or would include an untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made when such Time of Sale Information or Prospectus (or in lieu thereof, the Notice referred to in Rule 173(a) under the Act) is delivered, not misleading, or, if for any other reason it shall be necessary during such period to amend or supplement the Time of Sale Information or Prospectus or to file under the Exchange Act any document incorporated by reference in the Time of Sale Information or Prospectus in order to comply with the Act, the Exchange Act or the Trust Indenture Act, to notify the Representatives promptly and upon their reasonable request to file such document and to prepare and furnish without charge to each Underwriter and to any dealer in securities as many written and electronic copies as the Representatives may from time to time reasonably request of an amendment or supplement to the Time of Sale Information or Prospectus which will correct such conflict, statement or omission or effect such compliance;

(d)The Company shall make generally available to its securityholders and to the Representatives as soon as practicable, but in any event not later than eighteen months after the effective date of the Registration Statement (as defined in Rule 158), an earnings statement of the Company and its subsidiaries (which need not be audited) complying with Section 11(a) of the Act and the rules and regulations thereunder including Rule 158;

(e)The Company shall not for a period of      days following the Execution Time, without the prior written consent of the Representatives, offer, sell or contract to sell, or otherwise dispose of (or enter into any transaction which is designed to, or might reasonably be expected to, result in the disposition (whether by actual disposition or effective economic disposition due to cash settlement or otherwise) by the Company, directly or indirectly, or announce the offering of) any long-term Debt Securities issued or guaranteed by the Company, other than the Debt Securities;

(f)The Company shall use the net proceeds received by it from the sale of the Debt Securities pursuant to this Agreement in the manner specified in the Time of Sale Information and the Prospectus under the caption “Use of Proceeds”;

(g)The Company shall pay the costs and expenses relating to the following matters: (i) the preparation of the Supplemental Indenture, the issuance of the Debt Securities and the fees of the Trustee; (ii) the preparation, printing and filing of the Registration Statement (including all

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exhibits thereto), the Preliminary Prospectus, the Prospectus (including all documents incorporated by reference therein), the Time of Sale Information and any amendments thereof or supplements thereto and the printing and furnishing of such copies of each thereof to the Underwriters and to dealers (including postage, air freight charges and charges for counting and packaging), as may be reasonably requested for use in connection with the offering and sale of the Debt Securities; (iii) the preparation, printing, authentication, issuance and delivery of certificates for the Debt Securities, including any stamp or transfer taxes in connection with the original issuance and sale of the Debt Securities; (iv) the printing (or reproduction) and delivery of this Agreement, any blue sky memorandum and all other agreements or documents printed (or reproduced) and delivered in connection with the offering of the Debt Securities; (v) any registration or qualification of the Debt Securities for offer and sale under the securities or blue sky laws of the several states (including filing fees and the reasonable fees and expenses of counsel for the Underwriters relating to such registration and qualification); (vi) the transportation and other expenses incurred by or on behalf of Company representatives in connection with presentations to prospective purchasers of the Debt Securities; (vii) the fees and expenses of the Company’s accountants and counsel (including local and special counsel); (viii) the fees and expenses of any rating agencies rating the Debt Securities and (ix) all other costs and expenses incident to the performance by the Company of its obligations hereunder;

(h)Other than the Time of Sale Information listed on Schedule IV, without prior consent of the Representatives, it has not made and will not make any offer relating to the Debt Securities that would constitute a “free-writing prospectus” (as defined pursuant to Rule 405 under the Act).

(i)The Company will, pursuant to reasonable procedures developed in good faith, retain, as and to the extent required under Rule 433 of the Act, copies of each Issuer Free Writing Prospectus (as defined in Rule 433) that is not filed with the Commission in accordance with Rule 433 under the Act.

5.Certain Agreements of the Underwriters. Each Underwriter hereby represents and agrees as follows:

(a)It has not and will not use, authorize use of, refer to, or participate in the planning for use of, any “free writing prospectus,” as defined in Rule 405 under the Act (which term includes use of any written information furnished to the Commission by the Company and not incorporated by reference into the Registration Statement and any press release issued by the Company) other than (i) a free writing prospectus that contains no “issuer information” (as defined in Rule 433(h)(2) under the Act) that was not included (including through incorporation by reference) in the Preliminary Prospectus or a previously filed Issuer Free Writing Prospectus, (ii) any Issuer Free Writing Prospectus listed on Schedule IV hereto, or (iii) any free writing prospectus prepared by such Underwriter and approved by the Company in advance in writing (each such free writing prospectus referred to in clauses (i) or (iii), an “Underwriter Free Writing Prospectus”);

(b)It has not and will not distribute any Underwriter Free Writing Prospectus referred to in clause (a)(i) or (a)(iii) in a manner reasonably designed to lead to its broad unrestricted dissemination;

(c)It has not and will not, without the prior written consent of the Company, use any free writing prospectus that contains the final terms of the Debt Securities unless such terms have previously been included in a free writing prospectus filed with the Commission; provided that the Underwriters may use a term sheet substantially in the form of Schedule III hereto without the consent of the Company provided further that any Underwriter using such term sheet shall notify the Company, and provide a copy of such term sheet to the Company, prior to, or substantially concurrently with, the first use of such term sheet;

(d)It will, pursuant to reasonable procedures developed in good faith, retain, as and to the extent required under Rule 433 of Act, copies of each free writing prospectus used or referred to by it, in accordance with Rule 433 under the Act;

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(e)It is not subject to any pending proceeding under Section 8A of the Act with respect to the offering (and will promptly notify the Company if any such proceeding against it is initiated).

6.Conditions to the Obligations of the Underwriters. The obligations of the Underwriters to purchase the Debt Securities shall be subject to the accuracy of the representations and warranties on the part of the Company contained herein as of the date hereof and as of the Closing Date, to the accuracy of the statements of the Company made in any certificates delivered pursuant to the provisions hereof, to the performance by the Company of its obligations hereunder and to the following additional conditions:

(a)The Prospectus Supplement relating to the Debt Securities shall have been filed with the Commission pursuant to Rule 424(b) within the applicable time period prescribed for such filing by the rules and regulations under the Act and in accordance with Section 4(a) hereof; no stop order suspending the effectiveness of the Registration Statement or any part thereof shall have been issued and no proceeding for that purpose or pursuant to Section 8A shall have been initiated or threatened by the Commission; and all requests for additional information on the part of the Commission shall have been complied with to the Representatives’ reasonable satisfaction;

(b)The Representatives shall be furnished with opinions, dated the Closing Date, of Paula M. Connelly, Assistant General Counsel of Xcel Energy Services, Inc., attorney for the Company, and Jones Day, counsel for the Company, substantially in the forms included as Exhibits A and B respectively;

(c)The Representatives shall have received from Dewey Ballantine LLP, counsel for the Underwriters, such opinion or opinions dated the Closing Date with respect to such matters as the Representatives may reasonably require, and the Company shall have furnished to such counsel such documents as they reasonably request for the purpose of enabling them to pass upon such matters;

(d)The Company shall have furnished to the Representatives a certificate of the President or any Vice President of the Company, dated the Closing Date, as to the matters set forth in clause (a) and (h) of this Section 6 and to the further effect that the signers of such certificate have carefully examined the Registration Statement, the Prospectus, the Time of Sale Information and this Agreement and that:

(i)the representations and warranties of the Company in this Agreement are true and correct on and as of the Closing Date with the same effect as if made on the Closing Date, and the Company has complied with all the agreements and satisfied all the conditions on its part to be performed or satisfied at or prior to the Closing Date; and

(ii)since the date of the most recent financial statements included or incorporated by reference in the Prospectus and the Time of Sale Information, there has been no material adverse change in the condition of the Company, financial or otherwise, or in the earnings, affairs or business prospects of the Company, whether or not arising in the ordinary course of business, from that set forth or contemplated by the Registration Statement, the Time of Sale Information on the Prospectus;

(e)The Representatives shall have received letters from Deloitte & Touche LLP, independent public accountant for the Company (dated the date of this Agreement and Closing Date, respectively, and in form and substance satisfactory to the Representatives) advising that (i) they are an independent registered public accounting firm with respect to the Company as required by the Act and published rules and regulations of the Commission thereunder, (ii) in their opinion, the financial statements and supplemental schedules incorporated by reference in the Registration Statement, the Time of Sale Information or Prospectus and covered by their opinion filed with the Commission under Section 13 of the Exchange Act comply as to form in all material respects with the applicable accounting requirements of the Exchange Act and the published rules and regulations of the Commission thereunder, (iii) they have performed limited procedures, not constituting an audit, including a reading of the latest available interim financial statements of the

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Company, a reading of the minutes of meetings of the Board of Directors, committees thereof, and of the Shareholder of the Company since the date of the most recent audited financial statements included or incorporated by reference in the Prospectus and the Time of Sale Information, inquiries of officials of the Company responsible for financial accounting matters and such other inquiries and procedures as may be specified in such letter, and on the basis of such limited review and procedures nothing came to their attention that caused them to believe that: (A) any material modifications should be made to any unaudited financial statements of the Company included or incorporated by reference in the Registration Statement, the Time of Sale Information or Prospectus for them to be in conformity with generally accepted accounting principles or that any unaudited consolidated financial statements of the Company included or incorporated by reference in the Registration Statement, the Time of Sale Information or Prospectus do not comply as to form in all material respects with the applicable accounting requirements of the Exchange Act and the rules and regulations of the Commission applicable to Form 10-Q; (B) with respect to the period subsequent to the date of the most recent financial statements included or incorporated by reference in the Prospectus and except as set forth in or contemplated by the Registration Statement, the Time of Sale Information or Prospectus, there were any changes, at a specified date not more than five Business Days prior to the date of the letter, in the capital stock of the Company, increases in long-term debt or decreases in stockholders’ equity or net current assets of the Company as compared with the amounts shown on the most recent consolidated balance sheet included or incorporated in the Prospectus and the Time of Sale Information, or for the period from the date of the most recent financial statements included or incorporated by reference in the Prospectus and the Time of Sale Information to such specified date there were any decreases, as compared with the corresponding period in the preceding year, in operating revenues, operating income or net income of the Company, except in all instances for changes or decreases set forth in such letter, in which case the letter shall be accompanied by an explanation by the Company as to the significance thereof unless said explanation is not deemed necessary by the Representatives; and (iv) they have carried out specified procedures performed for the purpose of comparing certain specified financial information and percentages (which is limited to financial information derived from general accounting records of the Company or, to the extent not so derived, from schedules prepared by Company officers responsible for such accounting records) included or incorporated by reference in the Registration Statement, the Time of Sale Information and Prospectus with indicated amounts in the financial statements or accounting records of the Company and (excluding any questions of legal interpretation) have found such information and percentages to be in agreement with the relevant accounting and financial information of the Company referred to in such letter in the description of the procedures performed by them;

(f)Subsequent to the respective dates as of which information is given in the Registration Statement, Time of Sale Information and the Prospectus, there shall not have been (i) any change or decrease specified in the letter or letters referred to in paragraph (e) of this Section 6; or (ii) any change, or any development involving a prospective change, in or affecting the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries, taken as a whole, whether or not arising from transactions in the ordinary course of business, except as set forth in or contemplated in the Registration Statement, the Time of Sale Information and Prospectus the effect of which, in any case referred to in clause (i) or (ii) above, is, in the sole judgement of the Representatives, material and adverse and makes it impracticable or inadvisable to market the Debt Securities as contemplated by the Prospectus and the Time of Sale Information;

(g)Subsequent to the date hereof, there shall not have been any decrease in the rating or outlook of any of the Company’s Debt Securities by any “nationally recognized statistical rating organization” (as defined for purposes of Rule 436(g)(2) under the Act) or any public announcement of any intended or potential decrease in any such rating or outlook or of a possible change in any such rating or outlook that does not indicate the direction of the possible change;

(h)The Company shall have complied with the provisions of Section 4(c) hereof with respect to the furnishing of prospectuses;

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(i)Prior to the Closing Date, the Company shall have furnished to the Representatives such further information, certificates and documents as the Representatives may reasonably request.

If any of the conditions specified in this Section 6 shall not have been fulfilled in all material respects when and as provided in this Agreement, or if any of the opinions and certificates mentioned above or elsewhere in this Agreement shall not be in all material respects reasonably satisfactory in form and substance to the Representatives and their counsel, this Agreement and all obligations of the Underwriters hereunder may be cancelled at, or at any time prior to, the Closing Date by the Representatives. Notice of such cancellation shall be given to the Company in writing, or by telephone or telegraph confirmed in writing.

7.Conditions of Company’s Obligations. The obligations of the Company to sell and deliver the Debt Securities are subject to the following conditions:

(a)Prior to the Closing Date, no stop order suspending the effectiveness of the Registration Statement shall have been issued and no proceedings for that purpose shall have been instituted or, to the knowledge of the Company or the Representatives, threatened;

(b)At the Closing Date, the order of the Public Utilities Commission of the State of Colorado authorizing and approving the issuance and sale of the Debt Securities shall be final and in full force and effect and the time for appeal therefrom or review thereof or intervention with respect thereto shall have expired.

If any of the conditions specified in this Section 7 shall not have been fulfilled, this Agreement and all obligations of the Company hereunder may be cancelled on or at any time prior to the Closing Date by the Company. Notice of such cancellation shall be given to the Underwriters in writing or by telephone or facsimile transmission confirmed in writing.

8.Reimbursement of Underwriters’ Expenses.  If the sale of the Debt Securities provided for herein is not consummated because any condition to the obligations of the Underwriters set forth in Section 6 hereof is not satisfied or because of any refusal, inability or failure on the part of the Company to perform any agreement herein or comply with any provision hereof, other than by reason of a default by any of the Underwriters, the Company will reimburse the Underwriters severally upon demand for all out-of-pocket expenses that shall have been reasonably incurred by them in connection with the proposed purchase and sale of the Debt Securities, including the reasonable fees and disbursements of counsel for the Underwriters.

9.Indemnification.

(a)The Company agrees to indemnify and hold harmless each Underwriter, the directors, members, officers, employees and agents of each Underwriter and each person who controls any Underwriter within the meaning of either the Act or the Exchange Act against any and all losses, claims, damages or liabilities, joint or several, to which they or any of them may become subject under the Act, the Exchange Act or other Federal or state statutory law or regulation, at common law or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement or any amendment thereto, in the Time of Sale Information or Issuer Free Writing Prospectus or in the Prospectus or any amendment or supplement thereto, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, and agrees to reimburse each such indemnified party, as incurred, for any legal or other expenses reasonably incurred by them in connection with investigating or defending any such loss, claim, damage, liability or action; provided, however, that the Company will not be liable in any such case to the extent that any such loss, claim, damage or liability arises out of or is based upon any such untrue statement or alleged untrue statement or omission or alleged omission made in the Registration Statement or any amendment thereto, in the Time of Sale Information or any Issuer Free Writing Prospectus or in the Prospectus or any amendment or supplement thereto, in reliance upon and in

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conformity with written information furnished to the Company by or on behalf of any Underwriter through the Representatives specifically for inclusion therein; provided, further, that with respect to any such untrue statement in or omission from any Time of Sale Information or Issuer Free Writing Prospectus, the indemnity contained in this paragraph (a) shall not inure to the benefit of any Underwriter or its directors, members, officers, employees and agents, and each person, if any, who controls such Underwriter to the extent that the sale to the person asserting any such loss, claim, damage or liability was an initial sale by such Underwriter and any such loss, claim, damage or liability of or with respect to such Underwriter results from the fact that both (i) to the extent required by applicable law, a copy of all of the Time of Sale Information (including each Issuer Free Writing Prospectus specified in Schedule IV) was not sent or given to such person at or prior to the sale of the Debt Securities to such person and (ii) the untrue statement in or omission from such Time of Sale Information or Issuer Free Writing Prospectus was corrected in the undelivered Time of Sale Information unless, in either case, such failure to deliver all of the Time of Sale Information was a result of non-compliance by the Company with the provisions of Section 4(c) hereof. This indemnity agreement will be in addition to any liability which the Company may otherwise have;

(b)Each Underwriter severally and not jointly agrees to indemnify and hold harmless the Company, and each of its directors, officers, employees and agents, and each person who controls the Company within the meaning of either the Act or the Exchange Act, to the same extent as the foregoing indemnity from the Company to each Underwriter, but only with reference to written information relating to such Underwriter furnished to the Company by or on behalf of such Underwriter through the Representatives specifically for inclusion in the Registration Statement or any amendment thereto, Time of Sale Information or in the Prospectus or any amendment or supplement thereto. This indemnity agreement will be in addition to any liability which such Underwriter may otherwise have. The Company acknowledges that the statements set forth in                     in the Time of Sale Information and Prospectus constitute the only information furnished in writing by or on behalf of the Underwriters for inclusion in the Prospectus (or any amendment or supplement thereto);

(c)Promptly after receipt by an indemnified party under this Section 9 of notice of the commencement of any action, such indemnified party will, if a claim in respect thereof is to be made against the indemnifying party under this Section 9, notify the indemnifying party in writing of the commencement thereof; but the failure so to notify the indemnifying party (i) will not relieve the indemnifying party from liability under paragraph (a) or (b) above unless and to the extent it did not otherwise learn of such action and such failure results in the forfeiture by the indemnifying party of substantial rights and defenses; and (ii) will not, in any event, relieve the indemnifying party from any obligations to any indemnified party other than the indemnification obligation provided in paragraph (a) or (b) above. The indemnifying party shall be entitled to appoint counsel of the indemnifying party’s choice at the indemnifying party’s expense to represent the indemnified party in any action for which indemnification is sought (in which case the indemnifying party shall not thereafter be responsible for the fees and expenses of any separate counsel retained by the indemnified party or parties except as set forth below); provided, however, that such counsel shall be reasonably satisfactory to the indemnified party. Notwithstanding the indemnifying party’s election to appoint counsel to represent the indemnified party in an action, the indemnified party shall have the right to employ separate counsel (including local counsel), and the indemnifying party shall bear the reasonable fees, costs and expenses of such separate counsel if (i) the use of counsel chosen by the indemnifying party to represent the indemnified party would present such counsel with a conflict of interest; (ii) the actual or potential defendants in, or targets of, any such action include both the indemnified party and the indemnifying party and the indemnified party shall have reasonably concluded that there may be legal defenses available to it and/or other indemnified parties which are different from or additional to those available to the indemnifying party; (iii) the indemnifying party shall not have employed counsel satisfactory to the indemnified party to represent the indemnified party within a reasonable time after notice of the institution of such action; or (iv) the indemnifying party shall authorize the indemnified party to employ separate counsel at the expense of the indemnifying party; it being

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understood, however, that in each case the indemnifying party shall not, in connection with any one such action or separate but substantially similar or related actions in the same jurisdiction arising out of the same general allegations or circumstances, be liable for the reasonable fees and expenses of more than one separate firm of attorneys (in addition to any local counsel) at any time for all such indemnified parties, which firm shall be designated by the Representatives if the indemnified parties consist of the Underwriters or their directors, members, officers, employees or agents. An indemnifying party will not, without the prior written consent of the indemnified parties, settle or compromise or consent to the entry of any judgment with respect to any pending or threatened claim, action, suit or proceeding in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified parties are actual or potential parties to such claim or action) unless such settlement, compromise or consent includes an unconditional release of each indemnified party from all liability arising out of such claim, action, suit or proceeding;

(d)In the event that the indemnity provided in paragraph (a) or (b) of this Section 9 is for any reason held to be unenforceable by an indemnified party although applicable in accordance with its terms, the Company and the Underwriters agree to contribute to the aggregate losses, claims, damages and liabilities (including legal or other expenses reasonably incurred in connection with investigating or defending same) (collectively, “Losses”) to which the Company and one or more of the Underwriters may be subject in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand and by the Underwriters on the other from the offering of the Debt Securities; provided, however, that in no case shall any Underwriter (except as may be provided in any agreement among the Underwriters relating to the offering of the Debt Securities) be responsible for any amount in excess of the purchase discount or commission applicable to the Debt Securities purchased by such Underwriter hereunder; provided, further, that each Underwriter’s obligation to contribute to Losses hereunder shall be several and not joint. If the allocation provided by the immediately preceding sentence is unavailable for any reason, the Company and the Underwriters shall contribute in such proportion as is appropriate to reflect not only such relative benefits but also the relative fault of the Company on the one hand and of the Underwriters on the other in connection with the statements or omissions which resulted in such Losses, as well as any other relevant equitable considerations. Benefits received by the Company shall be deemed to be equal to the total net proceeds from the offering (before deducting expenses) received by it, and benefits received by the Underwriters shall be deemed to be equal to the total underwriting discounts and commissions in each case set forth on the cover of the Prospectus Supplement. Relative fault shall be determined by reference to, among other things, whether any untrue or any alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information provided by the Company on the one hand or the Underwriters on the other, the intent of the parties and their relative knowledge, information and opportunity to correct or prevent such untrue statement or omission. The Company and the Underwriters agree that it would not be just and equitable if contribution were determined by pro rata allocation or any other method of allocation which does not take account of the equitable considerations referred to above. Notwithstanding the provisions of this paragraph (d), no person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. For purposes of this Section 9, each person who controls an Underwriter within the meaning of either the Act or the Exchange Act and each director, member, officer, employee and agent of an Underwriter shall have the same rights to contribution as such Underwriter, and each person who controls the Company within the meaning of either the Act or the Exchange Act and each officer, director, member, employee or agent of the Company shall have the same rights to contribution as the Company, subject in each case to the applicable terms and conditions of this paragraph (d).

10.Default by an Underwriter. If any one or more Underwriters shall fail to purchase and pay for any of the Debt Securities agreed to be purchased by such Underwriter hereunder and such failure to purchase shall constitute a default in the performance of its or their obligations under this Agreement, the remaining Underwriters shall be obligated severally to take up and pay for (in the respective proportions which the principal amount of Debt Securities set forth opposite their names in Schedule I hereto bear to the

14

aggregate principal amount of Debt Securities set forth opposite the names of all the remaining Underwriters) the Debt Securities which the defaulting Underwriter or Underwriters agreed but failed to purchase; provided, however, that in the event that the aggregate principal amount of Debt Securities which the defaulting Underwriter or Underwriters agreed but failed to purchase shall exceed 10% of the aggregate amount of Debt Securities set forth in Schedule I hereto, the remaining Underwriters shall have the right to purchase all, but shall not be under any obligation to purchase any, of the Debt Securities, and if such nondefaulting Underwriters do not purchase all the Debt Securities, this Agreement will terminate without liability to any nondefaulting Underwriter or the Company. In the event of a default by any Underwriter as set forth in this Section 10, the Closing Date may be postponed for such period, not exceeding five Business Days, as the Representatives shall determine in order to effect whatever changes may thereby be made necessary in the Registration Statement or the Prospectus or any amendment or supplement to either thereof, or in any other documents or arrangements, and the Company agrees to file promptly any amendments or supplements to the Registration Statement or the Prospectus which in the opinion of the Representatives may thereby be made necessary. It is understood that any such postponement, change, amendment and/or supplement may require the establishment of a new “time of sale” and new “time of sale information”. The term “Underwriter” as used in this Agreement shall include any person substituted under this Section with like effect as if such person had originally been a party to this Agreement. Nothing contained in this Agreement shall relieve any defaulting Underwriter of its liability, if any, to the Company or any nondefaulting Underwriter for damages occasioned by its default hereunder.

11.Termination. This Agreement shall be subject to termination in the absolute discretion of the Representatives, by notice given to the Company prior to delivery of and payment for the Debt Securities, if at any time after the date hereof and prior to the delivery of and payment for the Debt Securities (i) trading in the common stock of Xcel Energy Inc. shall have been suspended by the Commission or the New York Stock Exchange or trading in securities generally on the New York Stock Exchange shall have been suspended or limited or minimum prices shall have been established on such Exchange; (ii) a banking moratorium shall have been declared either by Federal or New York State authorities; (iii) there shall have occurred a material disruption in commercial banking or securities settlement or clearance services in the United States or Europe; or (iv) there shall have occurred any outbreak or escalation of hostilities, declaration by the United States of a national emergency or war or other calamity or crisis the effect of which on financial markets is such as to make it, in the sole judgment of the Representatives, impracticable or inadvisable to proceed with the offering or delivery of the Debt Securities as contemplated by the Time of Sale Information and Prospectus.

12.Indemnities to Survive Delivery. The respective agreements, representations, warranties, indemnities and other statements of the Company or its officers and of the Underwriters set forth in or made pursuant to this Agreement will remain in full force and effect, regardless of any investigation made by or on behalf of any Underwriter or the Company or any of their respective officers, directors or controlling persons within the meaning of the Act, and will survive delivery of and payment for the Debt Securities. The provisions of Sections 8 and 9 hereof shall survive the termination or cancellation of this Agreement.

13.Notices. All communications hereunder will be in writing and, if sent to the Representatives, will be mailed, delivered or transmitted and confirmed to them at their address set forth for that purpose in Schedule I hereto or, if sent to the Company, will be mailed, delivered or transmitted and confirmed to it at                                                    , attention Secretary. All communications shall take effect at the time of receipt thereof.

14.Successors. This Agreement will inure to the benefit of and be binding upon the parties hereto and their respective successors and the officers and directors and controlling persons referred to in Section 9 hereof, and no other person will have any right or obligation hereunder.

15.Applicable Law. This Agreement will be governed by and construed in accordance with the laws of the State of New York applicable to contracts made and to be performed within the State of New York.

16.Counterparts. This Agreement may be executed in one or more counterparts, each of which shall constitute an original and all of which together shall constitute one and the same instrument.

15

17.Headings. The section headings used herein are for convenience only and shall not affect the construction hereof.

18.Other. As used herein, “Business Day” shall mean any day other than a Saturday, a Sunday or a legal holiday or a day on which banking institutions or trust companies are authorized or obligated by law to close in the City of New York.

19.Underwriters Counsel. The Company and the Underwriters acknowledge that Dewey Ballantine LLP (a) is acting as counsel to the Underwriters in connection with this Agreement and the transactions contemplated hereby and (b) has acted, and may continue to act, as counsel to the Company’s parent company, Xcel Energy Inc., and certain of its subsidiaries in connection with certain regulatory matters, and the Company and the Underwriters consent to such representation.

[signature page follows]

16

If the foregoing is in accordance with your understanding of our agreement, please sign and return to us the enclosed duplicate hereof, whereupon this letter and your acceptance shall represent a binding agreement among the Company and the several Underwriters.

		Very truly yours,
		PUBLIC SERVICE COMPANY OF COLORADO
		By
		[title]
The foregoing Agreement is hereby confirmed
and accepted as of the date first above written.
[NAME OF REPRESENTATIVE]
By
	For itself or themselves and as Representatives of the several Underwriters, if any, named in Schedule II to the foregoing Agreement.

SCHEDULE I

Underwriting Agreement dated

Registration Statement No. 333-

Representatives and Addresses:

Debt Securities:

Designation:
Principal Amount: $
Supplemental Indenture dated as of
Date of Maturity:
Interest Rate:	% per annum, payable                   and                  of each year,
	commencing
Purchase Price:	% of the principal amount thereof, plus accrued interest
	from                   to the date of payment and delivery.
Public Offering
Price:	% of the principal amount thereof, plus accrued interest
	from                          to the date of payment and delivery.
Redemption
Provisions:

Closing Date and Location:

Office for Delivery of Debt Securities:

Office for Payment of Debt Securities:

Office for Checking of Debt Securities:

SCHEDULE II

Name	Amount
Total	$

SCHEDULE III

PRICING INFORMATION

(To Prospectus Supplement dated           )

PUBLIC SERVICE COMPANY OF COLORADO

$              ,          % Senior Debt Securities, Series No.        due              

Issuer:	Public Service Company of Colorado
Size:	$
Maturity:	, 20
Coupon:	%
Price:	% of face amount
Interest Payment Dates:	and            , commencing
Redemption Provisions:
[First call date:	]
Redemption prices:
Settlement:	T |           ;          , 200
[CUSIP:	]
[Ratings	]
[Other Underwriters]

Note:  A securities rating is not a recommendation to buy, sell or hold securities and may be subject to revision or withdrawal at any time.

The issuer has filed a registration statement (including a prospectus) with the SEC for the offering to which this communication relates. Before you invest, you should read the prospectus in that registration statement and other documents the issuer has filed with the SEC for more complete information about the issuer and this offering. You may get these documents for free by visiting EDGAR on the SEC website at www.sec.gov. Alternatively, the issuer, any underwriter or any dealer participating in the offering will arrange to send you the prospectus if you request it by calling collect at                  .

SCHEDULE IV

Time of Sale Information

Preliminary Prospectus dated

Pricing Information as set forth in Schedule III

EXHIBIT A

FORM OF OPINION OF PAULA M. CONNELLY

Ladies and Gentlemen:

For the purpose of rendering this opinion, I have examined the proceedings taken by Public Service Company of Colorado, a Colorado corporation (the “Company”), with respect to the issue and sale by the Company of $                   principal amount of $                 Senior Debt Securities, Series No.        due            (the “Debt Securities”).  In connection therewith I have participated in the preparation of the proceedings for the issuance and sale of the Debt Securities including the Underwriting Agreement dated                         , between you and the Company relating to your purchase of the Debt Securities (the “Agreement”), and have either participated in the preparation of or examined the Trust Indenture dated July 1, 1999, from the Company to the Bank of New York, as trustee (the “Trustee”), as heretofore supplemented and as it will be further supplemented by Supplemental Indenture No.        creating the Debt Securities (said indenture, as so supplemented and to be further supplemented, being hereafter referred to as the “Indenture”).  This letter is furnished to the Underwriters pursuant to Section 6(b) of the Agreement.  Except as otherwise defined herein, terms used in this letter that are defined in the Agreement are used herein as so defined.  I also have participated in the preparation of or examined the registration statement and any amendments thereto and the accompanying prospectuses and any amendments or supplements thereto, as filed under the Act, with respect to the Debt Securities.  My examination has extended to all statutes, records, instruments, and documents which I have deemed necessary to examine for the purposes of this opinion.

I am of the opinion that:

1.             The Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of the State of Colorado with corporate power and authority to own, lease and operate its properties and conduct its business as described in the Prospectus and to enter into and perform its obligations under the Agreement;

2.             The Agreement and the Indenture have been duly authorized, executed and delivered by the Company; the issuance and sale of the Debt Securities have been duly authorized by all necessary corporate actions of the Company;

3.             The issuance and sale of the Debt Securities have been duly authorized and approved by an order of The Public Utilities Commission of the State of Colorado and such and such order is final and in full force and effect on the date hereof, the time for appeal therefrom or review thereof or intervention with respect thereto having expired; no further approval, authorization, consent or other order of any public board or body in the State of Colorado is legally required in connection with the transactions contemplated by the Agreement or Indenture, except as may be required under the blue sky laws of any jurisdiction in connection with the purchase and distribution of the Debt Securities by the Underwriters in the manner contemplated by the Agreement and in the Prospectus;

4.             Neither the execution and delivery of the Agreement, the issue and sale of the Debt Securities, nor the consummation of any other of the transactions therein contemplated, nor the fulfillment of the terms thereof will conflict with, result in a breach or violation or imposition of any lien, charge or encumbrance upon any property or assets of the Company or any of its subsidiaries, other than the security interest created by the Debt Securities and the Indenture under (i) the Restated Articles of Incorporation, as amended, or By-Laws of the Company or any of its subsidiaries; (ii) the terms of any indenture, contract, lease, mortgage, deed of trust, note agreement, loan agreement or other agreement, obligation, condition, covenant or instrument to which the Company or any of its subsidiaries is a party or bound or to which its or their property is subject; or (iii) any statute, law, rule, regulation, judgment, order or decree applicable to the Company or any of its subsidiaries of any court, regulatory body, administrative agency, governmental body, arbitrator or other authority having jurisdiction over the Company or any of its subsidiaries or any of its or their properties except, in the case of clause (ii) or (iii), any such conflict, breach or violation, if it did exist, would not, individually or in the aggregate, have a material adverse change in the condition (financial or otherwise), prospects, earnings, business or properties of the Company and its subsidiaries taken as a whole, whether or not arising from transactions in the ordinary course of business;

5.             The facsimile signature of a Senior Vice President or Vice President of the Company in lieu of his manual signature on the Debt Securities and the facsimile signature of the Secretary or an Assistant Secretary of the Company attesting the corporate seal in lieu of his manual signature on the Debt Securities have been duly and properly authorized by the Board of Directors of the Company, are not inconsistent with the provisions of the Restated Articles of Incorporation, as amended, or By-Laws of the Company and are valid and effective under the laws of the State of Colorado; and the facsimile signatures of such officers on the Debt Securities have the same legal effect as though they had manually signed and attested the Debt Securities as such respective officers;

6.             The descriptions in the Registration Statement, Time of sale Information and Prospectus of Colorado state statutes and legal and governmental proceedings are accurate in all material respects; to the best of my knowledge, there are no franchises, contracts, indentures, mortgages, loan agreements, notes, leases or other instruments that would be required to be described in the documents incorporated by reference in the Prospectus that are not described or referred to in such incorporated documents, and the descriptions thereof or references thereto are correct in all material respects;

7.             There is no pending, or to my knowledge, threatened suit or proceeding before any court or governmental agency, authority or body or any arbitration involving the Company or any of its subsidiaries required to be disclosed in the Prospectus which is not adequately disclosed in the Prospectus; and

8.             The franchises held by the Company, together with the applicable Certificates of Convenience and Necessity issued by The Public Utilities Commission of the State of Colorado, give the Company all necessary authority for the maintenance and operation of its properties and business as now conducted, and are free from burdensome restrictions or conditions of an unusual character.

In the course of my participation in the preparation or examination of the Registration Statement and any amendments thereto, the Time of Sale Information and the Prospectus and any amendments or supplements thereto, I made investigations as to the accuracy of certain of the statements of fact contained therein, I discussed other matters with officers, employees, and representatives of the Company, and I examined various corporate records and data. While I do not pass upon or assume responsibility for, and shall not be deemed to have independently verified, the accuracy and completeness of the statements contained in the Registration Statement or the Prospectus (except as to matters set forth in paragraphs 11 and 12 above), nothing has come to my attention that would lead me to believe that the Registration Statement, at the time it became effective, contained an untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary in order to make the statements therein, not misleading, that the Time of Sale Information, as of                       , included any untrue statement of a material fact or omitted to state a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading, or that the Prospectus, at the time it was filed with the Commission pursuant to Rule 424(b) under the Act and at the date hereof, contained or contains an untrue statement of material fact or omitted or omits to state a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading.

My opinions herein are limited to the laws of the State of Colorado. For purposes of rendering their opinion of even date herewith to the Underwriters, Dewey Ballantine LLP are entitled to rely on my opinions in paragraphs 1, 2 and 3 above as to all matters of Colorado law as if such opinions were addressed to them.

Respectfully submitted,
By:
	Paula M. Connelly
	Assistant General Counsel
	Xcel Energy Services, Inc.

EXHIBIT B

FORM OF OPINION OF JONES DAY

[Insert Underwriters]

Ladies and Gentlemen:

We have acted as special counsel to Public Service Company of Colorado, a Colorado Corporation (the “Company”), in connection with the purchase from the Company by the Underwriters named in Schedule II to the Underwriting Agreement, dated                        (the “Underwriting Agreement”), by and between the Company and you, as Representatives of the several Underwriters named on Schedule II thereto (the “Underwriters”), of $                 aggregate principal amount of Senior Debt Securities (the “Debt Securities”), being issued on this date under the Company’s Indenture, dated as of July 1, 1999, as heretofore supplemented and as it is being further supplemented by a supplemental indenture creating the Debt Securities (said Indenture, as so supplemented, being hereafter referred to as the “Indenture”).  This opinion is furnished to the Representatives, as representatives for the Underwriters pursuant to Section 6(b) of the Underwriting Agreement. Terms used in this opinion that are defined in the Underwriting Agreement are used as so defined.

In connection with the opinions and views expressed herein, we have examined such documents, records and matters of law as we have deemed relevant or necessary for purposes of this opinion. Based upon the foregoing and subject to the further assumptions, qualifications and limitations stated herein, we are of the opinion that:

1.             Assuming that the Underwriting Agreement has been duly (a) authorized by the Company and (b) executed and delivered by the Company under Colorado law, the Underwriting Agreement has been duly executed and delivered by the Company to the extent such execution and delivery are matters of New York law.

2.             Assuming that (a) the Company is a corporation existing and in good standing under the laws of the State of Colorado and (b) the Indenture (i) has been (A) authorized by all necessary corporate action of the Company and (B) executed and delivered by the Company under the laws of the State of Colorado, (ii) does not violate the laws of the State of Colorado, and (iii) constitutes the valid and binding obligation of the Company under the laws of the State of Colorado, the Indenture constitutes a valid and binding obligation of the Company under New York law, enforceable against the Company in accordance with its terms.

3.             Assuming that (a) the Company is a corporation existing and in good standing under the laws of the State of Colorado and (b) the Debt Securities (i) have been (A) authorized by all necessary corporate action of the Company and (B) validly issued, executed and delivered by the Company under the laws of the State of Colorado, (ii) do not violate the laws of the State of Colorado, and (iii) constitute valid and binding obligations of the Company under the laws of the State of Colorado, the Debt Securities, when authenticated by the Trustee in accordance with the terms of the Indenture and delivered against payment therefor in accordance with the terms of the Underwriting Agreement, will constitute valid and binding obligations of the Company under New York law, enforceable against the Company in accordance with their terms.

4.             Assuming that the issuance and sale of the Debt Securities have been duly authorized and approved by an order of Public Utilities Commission of the State of Colorado and such order is final and in full force and effect on the date hereof, no consent, approval, authorization or order of, or filing with, any governmental agency or body or any court of the United States or the State of Colorado is required in connection with the issuance or sale of the Debt Securities by the Company to the Underwriters, except as may be required under (i) state securities or blue sky laws or (ii) the Securities Act of 1933 (the “Securities Act”), the Securities Exchange Act of 1934 or the Trust Indenture Act of 1939.

5.             The (i) execution, delivery and performance of (A) the Indenture by the Company and (B) the Underwriting Agreement by the Company, (ii) issuance and sale of the Debt Securities by the Company and (iii) compliance with the terms and provisions thereof by the Company will not violate any U.S. federal securities or State of New York law or regulation known to us to be generally applicable to transactions of this type, or any order or decree of any U.S. federal securities or State of New York court, arbitrator or governmental agency that is binding upon the Company or its property or any agreement to which the Company is a party or bound (this opinion being limited (i) to those orders and decrees identified on Exhibit A attached hereto and to those agreements identified on Exhibit B attached hereto, and (ii) in that we express no opinion with respect to any violation (a) not readily ascertainable from the face of any such order, decree or agreement, (b) arising under or based upon any cross default provision insofar as it relates to a default under an agreement not identified on Exhibit B attached hereto, or (c) arising as a result of any violation of any agreement or covenant by failure to comply with any financial or numerical requirement requiring computation).

6.             The Company is not required to register as an “investment company,” as such term is defined in the Investment Company Act of 1940.

7.             The statements contained in the Prospectus under the captions “Description of Senior Debt Securities” and “Supplemental Description of the Senior Debt Securities,” insofar as such statements purport to summarize legal matters or provisions of documents referred to therein, present fair summaries of such legal matters and documents.

We have participated in the preparation of the Company’s registration statement on Form S-3 (Registration No.                     ) (the “Registration Statement”), the prospectus, dated                      (the “Base Prospectus”), the preliminary prospectus supplement, dated                        (together with the Base Prospectus, the “Preliminary Prospectus”), the information identified on Schedule I hereto (together with the Preliminary Prospectus, the “Time of Sale Information”) and the prospectus supplement, dated                        (together with the Base Prospectus, the “Prospectus”).  From time to time, we have had discussions with certain officers, directors and employees of the Company, with representatives of Deloitte & Touche LLP, the independent registered public accounting firm who examined the financial statements of the Company included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus, with the Underwriters and with counsel to the Underwriters concerning the information contained in or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus and the proposed responses to various items in Form S-3.  Based upon our participation and discussions described above, we are of the view that the Registration Statement (including all information deemed to be part of and included therein pursuant to Rule 430B under the Securities Act), as of                       , which is the date you have identified as the earlier of the date the Prospectus was first used or the date of the first contract of sale of any Debt Securities (such date, the “Effective Date”), and the Prospectus, as of the Effective Date, complied as to form in all material respects to the requirements of the Securities Act and the rules and regulations of the Securities and Exchange Commission (the “Commission”) thereunder, except that we express no view with respect to (i) the financial statements, financial schedules and other financial and statistical data included or incorporated by reference therein or (ii) the information referred to under the caption “Experts” as having been included or incorporated by reference therein on the authority of Deloitte & Touche LLP as experts.

We have not independently verified and are not passing upon, and do not assume any responsibility for, the accuracy, completeness or fairness (except as and to the extent set forth in paragraph 7 above) of the information included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus.  Based upon our participation and discussions set forth above, however, no facts have come to our attention that cause us to believe that the Registration Statement (including all information deemed to be part of and included therein pursuant to Rule 430B under the Securities Act), as of the Effective Date, contained any untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary to make the statements therein not misleading, that the Time of Sale Information, as of            p.m. on                      (which is the time that you have informed us was prior to the first contract of sale of any Debt Securities by the Underwriters), included any untrue statement of a material fact or omitted to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading, or that the Prospectus, as of the Effective Date or on the date hereof, included or includes any untrue statement of a material fact or omitted or omits to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading, except that we express no view with respect to (i) the

financial statements, financial schedules and other financial and statistical data included or incorporated by reference therein or (ii) the information referred to under the caption “Experts” as having been included or incorporated by reference therein on the authority of Deloitte & Touche LLP as experts.

The Registration Statement has become effective under the Securities Act, and no stop order suspending the effectiveness of the Registration Statement has been issued and no proceedings for that purpose are pending or threatened by the Commission.

The opinions and views set forth above are subject to the following limitations, qualifications and assumptions:

We have assumed, for purposes of the opinions and views expressed herein, the legal capacity of all natural persons executing documents, the genuineness of all signatures, the authenticity of original and certified documents and the conformity to original or certified copies of all copies submitted to us as conformed or reproduction copies.  For the purposes of the opinions and views expressed herein, we also have assumed that the Trustee has authorized, executed, authenticated and delivered the documents or securities to which it is a party and that each of such documents or securities is the valid, binding and enforceable obligation of the Trustee.

As to facts material to the opinions and assumptions expressed herein, we have, with your consent, relied upon oral or written statements and representations of officers and other representatives of the Company and others, including the representations and warranties of the Company contained in the Underwriting Agreement.  We have not independently verified such matters.

Our opinions set forth in paragraphs 2 and 3 above with respect to the enforceability of the documents or securities referred to in such opinions are subject to: (i) bankruptcy, insolvency, reorganization, fraudulent transfer and fraudulent conveyance, voidable preference, moratorium or other similar laws, and related regulations and judicial doctrines from time to time in effect relating to or affecting creditors’ rights and remedies generally; (ii) general equitable principles, whether such principles are considered in a proceeding at law or in equity; (iii) the qualification that we express no opinion as to the validity, binding effect or enforceability of any provision in any document (A) relating to indemnification, contribution or exculpation in connection with violations of any securities laws or statutory duties or public policy, or in connection with willful, reckless or unlawful acts or gross negligence of the indemnified or exculpated party or the party receiving contribution, (B) relating to forum selection to the extent the forum is a federal court, (C) relating to forum selection to the extent that any relevant action or proceeding does not arise out of or relate to such document or to the extent that the enforceability of any such provision is to be determined by any court other than a court of the State of New York, (D) relating to choice of governing law to the extent that the enforceability of any such provision is to be determined by any court other than a court of the State of New York or may be subject to constitutional limitations or (E) specifying that provisions thereof may be waived only in writing, to the extent that an oral agreement or an implied agreement by trade practice or course of conduct has been created that modifies any provision of such documents; and (iv) the effect of applicable rules of law that (A) provide that forum selection clauses in contracts are not necessarily binding on the court in the forum selected, (B) may, where less than all of a contract may be unenforceable, limit the enforceability of the balance of the contract to circumstances in which the unenforceable portion is not an essential part of the agreed exchange, or that permit a court to reserve to itself a decision as to whether any provision of any agreement is severable, and (C) govern and afford judicial discretion regarding the determination of damages and entitlement to attorneys’ fees and other costs.

With respect to our opinions in paragraph 5, we express no opinion as to state securities or “blue sky” laws.

The statement above with respect to the effectiveness of the Registration Statement under the Securities Act is based solely on the Notice of Effectiveness relating to the Registration Statement as published by the Commission on its Web site on             .  In addition, the statement above with respect to no stop order suspending the effectiveness of the Registration Statement having been issued and no proceedings for that purpose being pending or threatened by the Commission are based solely on telephone conversations involving lawyers in our firm actively engaged in our representation of the Company in this matter and members of the staff of the Commission, and such statement is made as of the time of such conversations.

The opinions and views expressed herein are limited to (i) the federal laws of the United States of America and (ii) the laws of the State of New York, in each case as currently in effect, and we express no opinion or view as to the effect of the laws of any other jurisdiction on the opinions and views expressed herein.

We express no opinion or view as to the compliance or noncompliance, or the effect of the compliance or noncompliance, of each of the addressees or any other person or entity with any state or federal laws or regulations applicable to each of them by reason of their status as or affiliation with a federally insured depository institution.  Our opinions and views are limited to those expressly set forth herein, and we express no opinions or views by implication.

This letter is furnished by us to you solely for the benefit of the Underwriters and solely with respect to the purchase of the Debt Securities from the Company by the Underwriters, upon the understanding that we are not hereby assuming any professional responsibility to any other person whatsoever, and that this letter is not to be used, circulated, quoted or otherwise referred to for any other purpose.

Very truly yours,

EX-4.(A)(3)

Exhibit 4.(a)(3)

Form of Supplemental Indenture
(First Mortgage Bonds)

PUBLIC SERVICE COMPANY
OF COLORADO

TO

U.S. BANK TRUST NATIONAL ASSOCIATION,

AS TRUSTEE

SUPPLEMENTAL INDENTURE NO.      

Dated as of                       

Supplemental to the Indenture
dated as of October 1, 1993

Establishing the Securities of Series No.           
designated First Mortgage Bonds, Series No.             

SUPPLEMENTAL INDENTURE NO.     , dated as of                     , between PUBLIC SERVICE COMPANY OF COLORADO, a corporation duly organized and existing under the laws of the State of Colorado (hereinafter sometimes called the “Company”), and U.S. BANK TRUST NATIONAL ASSOCIATION (FORMERLY FIRST TRUST OF NEW YORK, NATIONAL ASSOCIATION), a national banking association, as successor trustee (hereinafter sometimes called the “Trustee”) to Morgan Guaranty Trust Company of New York under the Indenture, dated as of October 1, 1993 (hereinafter called the “Original Indenture”), as previously supplemented and as further supplemented by this Supplemental Indenture No.     . The Original Indenture and any and all indentures and all other instruments supplemental thereto are hereinafter sometimes collectively called the “Indenture”.

RECITALS OF THE COMPANY

The Original Indenture was authorized, executed and delivered by the Company to provide for the issuance from time to time of its Securities (such term and all other capitalized terms used herein without definition having the meanings assigned to them in the Original Indenture), to be issued in one or more series as contemplated therein, and to provide security for the payment of the principal of and premium, if any, and interest, if any, on the Securities.

The Company has heretofore executed and delivered to the Trustee the Supplemental Indentures referred to in Schedule A hereto for the purpose of establishing a series of bonds and appointing the successor Trustee.

The Company desires to establish a new series of Securities to be designated “First Mortgage Bonds, Series No.     ,” such series of Securities to be hereinafter sometimes called “Series No.     .”

The Company has duly authorized the execution and delivery of this Supplemental Indenture No.      to establish the Securities of Series No.      and has duly authorized the issuance of such Securities; and all acts necessary to make this Supplemental Indenture No.      a valid agreement of the Company, and to make the Securities of Series No.      valid obligations of the Company, have been performed.

GRANTING CLAUSES

NOW, THEREFORE, THIS SUPPLEMENTAL INDENTURE NO.        WITNESSETH, that, in consideration of the premises and of the purchase of the Securities by the Holders thereof, and in order to secure the payment of the principal of and premium, if any, and interest, if any, on all Securities from time to time Outstanding and the performance of the covenants contained therein and in the Indenture and to declare the terms and conditions on which such Securities are secured, the Company hereby grants, bargains, sells, releases, conveys, assigns, transfers, mortgages, pledges, sets over and confirms to the Trustee, and grants to the Trustee a security interest in, the following:

GRANTING CLAUSE FIRST

All right, title and interest of the Company, as of the date of the execution and delivery of this Supplemental Indenture No.     , in and to

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property (other than Excepted Property), real, personal and mixed and wherever situated, in any case used or to be used in or in connection with the Electric Utility Business (whether or not such use is the sole use of such property), including without limitation (a) all lands, easements, servitudes, licenses, permits, rights of way and other rights and interests in or relating to real property used or to be used in or in connection with the Electric Utility Business or relating to the occupancy or use of such real property, subject however, to the exceptions and exclusions set forth in clause (a) of Granting Clause First of the Original Indenture; (b) all plants, generators, turbines, engines, boilers, fuel handling and transportation facilities, air and water pollution control and sewage and solid waste disposal facilities and other machinery and facilities for the generation of electric energy; (c) all switchyards, lines, towers, substations, transformers and other machinery and facilities for the transmission of electric energy; (d) all lines, poles, conduits, conductors, meters, regulators and other machinery and facilities for the distribution of electric energy; (e) all buildings, offices, warehouses and other structures used or to be used in or in connection with the Electric Utility Business; (f) all pipes, cables, insulators, ducts, tools, computers and other data processing and/or storage equipment and other equipment, apparatus and facilities used or to be used in or in connection with the Electric Utility Business; (g) any or all of the foregoing properties in the process of construction; and (h) all other property, of whatever kind and nature, ancillary to or otherwise used or to be used in conjunction with any or all of the foregoing or otherwise, directly or indirectly, in furtherance of the Electric Utility Business;

GRANTING CLAUSE SECOND

Subject to the applicable exceptions permitted by Section 810(c), Section 1303 and Section 1305 of the Original Indenture, all property (other than Excepted Property) of the kind and nature described in Granting Clause First which may be hereafter acquired by the Company, it being the intention of the Company that all such property acquired by the Company after the date of the execution and delivery of this Supplemental Indenture No.      shall be as fully embraced within and subjected to the Lien hereof as if such property were owned by the Company as of the date of the execution and delivery of this Supplemental Indenture No.     ;

GRANTING CLAUSE FOURTH

All other property of whatever kind and nature subjected or required to be subjected to the Lien of the Indenture by any of the provisions thereof;

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EXCEPTED PROPERTY

Expressly excepting and excluding, however, from the Lien and operation of the Indenture all Excepted Property of the Company, whether now owned or hereafter acquired;

TO HAVE AND TO HOLD all such property, real, personal and mixed, unto the Trustee, its successors in trust and their assigns forever;

SUBJECT, HOWEVER, to (a) Liens existing at the date of the execution and delivery of the Original Indenture, (b) as to property acquired by the Company after the date of the execution and delivery of the Original Indenture, Liens existing or placed thereon at the time of the acquisition thereof (including, but not limited to, the Lien of any Class A Mortgage and purchase money Liens), (c) Retained Interests and (d) any other Permitted Liens, it being understood that, with respect to any property which was at the date of execution and delivery of the Original Indenture or thereafter became or hereafter becomes subject to the Lien of any Class A Mortgage, the Lien of the Indenture shall at all times be junior, subject and subordinate to the Lien of such Class A Mortgage;

IN TRUST, NEVERTHELESS, for the equal and proportionate benefit and security of the Holders from time to time of all Outstanding Securities without any priority of any such Security over any other such Security;

PROVIDED, HOWEVER, that the right, title and interest of the Trustee in and to the Mortgaged Property shall cease, terminate and become void in accordance with, and subject to the conditions set forth in, Article Nine of the Original Indenture, and if, thereafter, the principal of and premium, if any, and interest, if any, on the Securities shall have been paid to the Holders thereof, or shall have been paid to the Company pursuant to Section 603 of the Original Indenture, then and in that case the Indenture shall terminate, and the Trustee shall execute and deliver to the Company such instruments as the Company shall require to evidence such termination; otherwise the Indenture, and the estate and rights thereby granted shall be and remain in full force and effect; and

THE PARTIES HEREBY FURTHER COVENANT AND AGREE as follows:

Article One

SECURITIES OF SERIES NO.     

There are hereby established the Securities of Series No.     , which shall have the terms and characteristics set forth below (the lettered subdivisions set forth below corresponding to the lettered subdivisions of Section 301 of the Original Indenture):

(a)           the title of the Securities of Series No.      shall be “First Mortgage Bonds, Series No.     ”;

(b)           the Securities of Series No.      shall be initially authenticated and delivered in the aggregate principal amount of $                      ;

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(c)           interest on the Securities of Series No.      shall be payable to the Persons in whose names such Securities are registered at the close of business on the Regular Record Date for such interest, except as otherwise expressly provided in the form of such Securities attached as Exhibit A hereto;

(d)           the principal of the Securities of Series No.      shall be payable on                     , the Stated Maturity for Series No.     ;

(e)           the Securities of Series No.      shall bear interest at a rate of           % per annum; interest shall accrue on the Securities of Series No.      from                       , or the most recent date to which interest has been paid or duly provided for; the Interest Payment Dates for such Securities shall be                  and                in each year, commencing                   , and the Regular Record Dates with respect to the Interest Payment Dates for such Securities shall be                and                in each year, respectively (whether or not a Business Day);

(f)            the Corporate Trust Office of U.S. Bank Trust National Association in New York, New York shall be the place at which (i) the principal of, premium, if any, and interest, if any, on the Securities of Series No.      shall be payable, (ii) registration of transfer of such Securities may be effected, (iii) exchanges of such Securities may be effected and (iv) notices and demands to or upon the Company in respect of such Securities and the Indenture may be served; and U.S. Bank Trust National Association shall be the Security Registrar for such Securities; provided, however, that the Company reserves the right to change, by one or more Officer’s Certificates, any such place or the Security Registrar; and provided, further, that the Company reserves the right to designate, by one or more Officer’s Certificates, its principal office in Denver, Colorado as any such place or itself as the Security Registrar;

(g)           the Securities of Series No.      [shall not be redeemable prior to maturity] [shall be redeemable] at the option of the Company on and after                        in whole or part at a redemption price of             .

(h)           not applicable;

(i)            not applicable;

(j)            not applicable;

(k)           not applicable;

(l)            not applicable;

(m)          not applicable;

(n)           not applicable;

(o)           not applicable;

(p)           not applicable;

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(q)           the Securities of Series No.      are to be initially registered in the name of Cede & Co., as nominee for The Depository Trust Company (the “Depositary”).  Such Securities shall not be transferable or exchangeable, nor shall any purported transfer be registered, except as follows:

(i)            such Securities may be transferred in whole, and appropriate registration of transfer effected, if such transfer is by such nominee to the Depositary, or by the Depositary to another nominee thereof, or by any nominee of the Depositary to any other nominee thereof, or by the Depositary or any nominee thereof to any successor securities depositary or any nominee thereof; and

(ii)           such Securities may be exchanged for definitive Securities registered in the respective names of the beneficial holders thereof, and thereafter shall be transferable without restriction, if:

(A)          the Depositary, or any successor securities depositary, shall have notified the Company and the Trustee that it is unwilling or unable to continue to act as securities depositary with respect to such Securities or the Depositary has ceased to be a clearing agency registered under the Securities Exchange Act of 1934, as amended, and the Trustee shall not have been notified by the Company within ninety (90) days of the identity of a successor securities depositary with respect to such Securities; or

(B)           the Company shall have delivered to the Trustee a Company Order to the effect that such Securities shall be so exchangeable on and after a date specified therein;

(r)            not applicable;

(s)           no service charge shall be made for the registration of transfer or exchange of the Securities of Series No.     ; provided, however, that the Company may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection with the exchange or transfer;

(t)            not applicable;

(u)           (i)            If the Company shall have caused the Company’s indebtedness in respect of any Securities of Series No.      to have been satisfied and discharged prior to the Maturity of such Securities, as provided in Section 901 of the Original Indenture, the Company shall, promptly after the date of such satisfaction and discharge, give a notice to each Person who was a Holder of any of such Securities on such date stating (A)(1) the aggregate principal amount of such Securities and (2) the aggregate amount of any money (other than amounts, if any, deposited in respect of accrued interest on such Securities) and the aggregate principal amount of, the rate or rates of interest on, and the aggregate fair market value of, any Eligible Obligations deposited pursuant to Section 901 of the Original Indenture with respect to such Securities and (B) that the Company will provide (and the Company shall promptly so provide) to such Person, or any beneficial owner of such Securities holding through such Person (upon written request to the Company sent to an address specified in such notice), such other information as such Person or beneficial owner, as the case may be, reasonably may request in order to enable it to determine the federal income tax consequences to it resulting from the

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satisfaction and discharge of the Company’s indebtedness in respect of such Securities.  Thereafter, the Company shall, within forty-five (45) days after the end of each calendar year, give to each Person who at any time during such calendar year was a Holder of such Securities a notice containing (X) such information as may be necessary to enable such Person to report its income, gain or loss for federal income tax purposes with respect to such Securities or the assets held on deposit in respect thereof during such calendar year or the portion thereof during which such Person was a Holder of such Securities, as the case may be (such information to be set forth for such calendar year as a whole and for each month during such year) and (Y) a statement to the effect that the Company will provide (and the Company shall promptly so provide) to such Person, or any beneficial owner of such Securities holding through such Person (upon written request to the Company sent to an address specified in such notice), such other information as such Person or beneficial owner, as the case may be, reasonably may request in order to enable it to determine its income, gain or loss for federal income tax purposes with respect to such Securities or such assets for such year or portion thereof, as the case may be.  The obligation of the Company to provide or cause to be provided information for purposes of income tax reporting by any Person as described in the first two sentences of this paragraph shall be deemed to have been satisfied to the extent that the Company has provided or caused to be provided substantially comparable information pursuant to any requirements of the Internal Revenue Code of 1986, as amended from time to time (the “Code”) and United States Treasury regulations thereunder.

(ii)           Notwithstanding the provisions of subparagraph (i) above, the Company shall not be required to give any notice specified in such subparagraph or to otherwise furnish any of the information contemplated therein if the Company shall have delivered to the Trustee an Opinion of Counsel to the effect that the Holders of such Securities will not recognize income, gain or loss for federal income tax purposes as a result of the satisfaction and discharge of the Company’s indebtedness in respect of such Securities and such Holders will be subject to federal income taxation on the same amounts and in the same manner and at the same times as if such satisfaction and discharge had not occurred.

(iii)          Anything in this clause (u) to the contrary notwithstanding, the Company shall not be required to give any notice specified in subparagraph (i) or to otherwise furnish the information contemplated therein or to deliver any Opinion of Counsel contemplated by subparagraph (ii) if the Company shall have caused Securities of Series No.      to be deemed to have been paid for purposes of the Indenture, as provided in Section 901 of the Original Indenture, but shall not have effected the satisfaction and discharge of its indebtedness in respect of such Securities pursuant to such Section.

(iv)          The Securities of Series No.      shall be substantially in the form attached hereto as Exhibit A and shall have such further terms as are set forth in such form.

Article Two

MISCELLANEOUS PROVISIONS

This Supplemental Indenture No.      is a supplement to the Original Indenture.  As previously supplemented and further supplemented by this Supplemental Indenture No.     , the

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Original Indenture is in all respects ratified, approved and confirmed, and the Original Indenture, all previous supplements thereto and this Supplemental Indenture No.      shall together constitute one and the same instrument.

IN WITNESS WHEREOF, the parties hereto have caused this Supplemental Indenture No.      to be duly executed as of the day and year first above written.

		PUBLIC SERVICE COMPANY OF COLORADO
		By:
			Name:
			Title: Vice President and
STATE OF	)
	)  ss.:
CITY OF	)

On the        day of                       , before me personally came to me known, who, being by me duly sworn, did depose and say that he is a Vice President and                  of Public Service Company of Colorado, one of the corporations described in and which executed the foregoing instrument; and that he signed his name thereto by authority of the Board of Directors of said corporation.

Name:

Notary Public, State of

Commission Expires:

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		U.S. BANK TRUST NATIONAL ASSOCIATION
			By:
		Name:
		Title: Assistant Vice President
STATE OF NEW YORK	)
	)  ss.:
CITY AND COUNTY OF NEW YORK	)

On the        day of                         , before me personally came                           , to me known, who, being by me duly sworn, did depose and say that he is an Assistant Vice President of U.S. Bank Trust National Association, the banking association described in and which executed the foregoing instrument; and that he signed his name thereto by authority of the Board of Directors of said banking association.

Name:

Notary Public, State of New York

Commission Expires:

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EXHIBIT A

FORM OF SECURITY

(See legend at the end of this Security for
restrictions on transfer)

PUBLIC SERVICE COMPANY OF COLORADO
First Mortgage Bond, Series No.    

Original Interest Accrual Date:
Interest Rate:	%
Stated Maturity:
Interest Payment Dates:		and
Regular Record Dates:		and

This Security is not a Discount Security

within the meaning of the within mentioned Indenture

Principal Amount	Registered No.
$	CUSIP

PUBLIC SERVICE COMPANY OF COLORADO, a corporation duly organized and existing under the laws of the State of Colorado (herein called the “Company,” which term includes any successor corporation under the Indenture referred to below), for value received, hereby promises to pay to, or registered assigns, the principal sum of                                      Dollars on the Stated Maturity specified above, and to pay interest thereon from the Original Interest Accrual Date specified above or from the most recent Interest Payment Date to which interest has been paid or duly provided for, semi-annually in arrears on the Interest Payment Dates specified above in each year, commencing                       , and at Maturity, at the Interest Rate per annum specified above, until the principal hereof is paid or duly provided for.  The interest so payable, and paid or duly provided for, on any Interest Payment Date shall, as provided in such Indenture, be paid to the Person in whose name this Security (or one or more Predecessor Securities) is registered at the close of business on the Regular Record Date specified above (whether or not a Business Day) next preceding such Interest Payment Date.  Notwithstanding the foregoing, interest payable at Maturity shall be paid to the Person to whom principal shall be paid.  Except as otherwise provided in said Indenture, any such interest not so paid or duly provided for shall forthwith cease to be payable to the Holder on such Regular Record Date and may either be paid to the Person in whose name this Security (or one or more Predecessor Securities) 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 of which shall be given to Holders of Securities of this series not less than 15 days prior to such Special Record Date, or be paid in such other manner as permitted by the Indenture.

Payment of the principal of this Security and interest hereon at Maturity shall be made upon presentation of this Security at the Corporate Trust Office of U.S. Bank Trust National

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Association, in New York, New York or at such other office or agency as may be designated for such purpose by the Company from time to time.  Payment of interest on this Security (other than interest at Maturity) shall be made by check mailed to the address of the Person entitled thereto as such address shall appear in the Security Register, except that if such Person shall be a securities depositary, such payment may be made by such other means in lieu of check as shall be agreed upon by the Company, the Trustee and such Person.  Payment of the principal of and interest on this Security, as aforesaid, shall be made in such coin or currency of the United States of America as at the time of payment shall be legal tender for the payment of public and private debts.

This Security is one of a duly authorized issue of securities of the Company (herein called the “Securities”), issued and issuable in one or more series under and equally secured by an Indenture, dated as of October 1, 1993 (such Indenture as originally executed and delivered and as supplemented or amended from time to time thereafter, together with any constituent instruments establishing the terms of particular Securities, being herein called the “Indenture”), between the Company and U.S. Bank Trust National Association (formerly First Trust of New York, National Association) as successor trustee (herein called the “Trustee,” which term includes any successor trustee under the Indenture), to which Indenture and all indentures supplemental thereto reference is hereby made for a description of the property mortgaged, pledged and held in trust, the nature and extent of the security and the respective rights, limitations of rights, duties and immunities of the Company, the Trustee and the Holders of the Securities thereunder and of the terms and conditions upon which the Securities are, and are to be, authenticated and delivered and secured.  The acceptance of this Security shall be deemed to constitute the consent and agreement by the Holder hereof to all of the terms and provisions of the Indenture.  This Security is one of the series designated above.

If any Interest Payment Date or the Stated Maturity shall not be a Business Day (as hereinafter defined), payment of the amounts due on this Security on such date may be made on the next succeeding Business Day; and, if such payment is made or duly provided for on such Business Day, no interest shall accrue on such amounts for the period from and after such Interest Payment Date or Stated Maturity, as the case may be, to such Business Day.

This Security [shall not be redeemable] [shall be redeemable at the option of the Company on and after                        in whole or in part, at a redemption price equal to                           ].

If an Event of Default shall occur and be continuing, the principal of this Security 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 Trustee to enter into one or more supplemental indentures for the purpose of adding any provisions to, or changing in any manner or eliminating any of the provisions of, the Indenture with the consent of the Holders of not less than a majority in aggregate principal amount of the Securities of all series then Outstanding under the Indenture, considered as one class; provided, however, that if there shall be Securities of more than one series Outstanding under the Indenture and if a proposed supplemental indenture shall directly affect the rights of the Holders of Securities of one or more, but less than all, of such series, then the consent only of the Holders of a majority in

A-2

aggregate principal amount of the Outstanding Securities of all series so directly affected, considered as one class, shall be required; and provided, further, that if the Securities of any series shall have been issued in more than one Tranche and if the proposed supplemental indenture shall directly affect the rights of the Holders of Securities of one or more, but less than all, of such Tranches, then the consent only of the Holders of a majority in aggregate principal amount of the Outstanding Securities of all Tranches so directly affected, considered as one class, shall be required; and provided, further, that the Indenture permits the Trustee to enter into one or more supplemental indentures for limited purposes without the consent of any Holders of Securities.  The Indenture also contains provisions permitting the Holders of a majority in principal amount of the Securities then Outstanding, on behalf of the Holders of all Securities, to waive compliance by the Company with certain provisions of the Indenture and certain past defaults under the Indenture and their consequences.  Any such consent or waiver by the Holder of this Security shall be conclusive and binding upon such Holder and upon all future Holders of this Security and of any Security issued upon the registration of transfer hereof or in exchange therefor or in lieu hereof, whether or not notation of such consent or waiver is made upon this Security.

As provided in the Indenture and subject to certain limitations therein set forth, this Security or any portion of the principal amount hereof will be deemed to have been paid for all purposes of the Indenture and to be no longer Outstanding thereunder, and, at the election of the Company, the Company’s entire indebtedness in respect thereof will be satisfied and discharged, if there has been irrevocably deposited with the Trustee or any Paying Agent (other than the Company), in trust, money in an amount which will be sufficient and/or Eligible Obligations, the principal of and interest on which when due, without regard to any reinvestment thereof, will provide moneys which, together with moneys so deposited, will be sufficient, to pay when due the principal of and interest on this Security when due.

As provided in the Indenture and subject to certain limitations therein set forth, the transfer of this Security is registrable in the Security Register, upon surrender of this Security for registration of transfer at the office of U.S. Bank Trust National Association, in New York, New York or such other office or agency as may be designated by the Company from time to time, duly endorsed by, or accompanied by a written instrument of transfer in form satisfactory to the Company and the Security Registrar duly executed by, the Holder hereof or his attorney duly authorized in writing, and thereupon one or more new Securities of this series of authorized denominations and of like tenor and aggregate principal amount, will be issued to the designated transferee or transferees.

The Securities of this series are issuable only as registered Securities, without coupons, and in denominations of $1,000 and integral multiples thereof.  As provided in the Indenture and subject to certain limitations therein set forth, Securities of this series are exchangeable for a like aggregate principal amount of Securities of the same series, of any authorized denominations, as requested by the Holder surrendering the same, and of like tenor upon surrender of the Security or Securities to be exchanged at the office of U.S. Bank Trust National Association, in New York, New York or such other office or agency as may be designated by the Company from time to time.

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No service charge shall be made for any such registration of transfer or exchange, but the Company may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith.

Prior to due presentment of this Security for registration of transfer, the Company, the Trustee and any agent of the Company or the Trustee may treat the Person in whose name this Security is registered as the absolute owner hereof for all purposes, whether or not this Security be overdue, and neither the Company, the Trustee nor any such agent shall be affected by notice to the contrary.

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

As used herein “Business Day” means any day, other than a Saturday or Sunday, which is not a day on which banking institutions or trust companies in The City of New York, New York or other city in which is located any office or agency maintained for the payment of principal or interest on this Security, are authorized or required by law, regulation or executive order to remain closed.  All other terms used in this Security which are defined in the Indenture shall have the meanings assigned to them in the Indenture.

As provided in the Indenture, no recourse shall be had for the payment of the principal of or interest on any Securities, or any part thereof, or for any claim based thereon or otherwise in respect thereof, or of the indebtedness represented thereby, or upon any obligation, covenant or agreement under the Indenture, against, and no personal liability whatsoever shall attach to, or be incurred by, any incorporator, shareholder, officer or director, as such, past, present or future of the Company or of any predecessor or successor corporation (either directly or through the Company or a predecessor or successor corporation), whether by virtue of any constitutional provision, statute or rule of law, or by the enforcement of any assessment or penalty or otherwise; it being expressly agreed and understood that the Indenture and all the Securities are solely corporate obligations and that any such personal liability is hereby expressly waived and released as a condition of, and as part of the consideration for, the execution of the Indenture and the issuance of the Securities.

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

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IN WITNESS WHEREOF, the Company has caused this instrument to be duly executed and its corporate seal to be hereunto affixed and attested.

		PUBLIC SERVICE COMPANY OF COLORADO
		By:
			[Title]
Attest:
	[Title]

CERTIFICATE OF AUTHENTICATION

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

Dated:
U.S. BANK TRUST NATIONAL ASSOCIATION, as Trustee		OR	U.S. BANK TRUST NATIONAL ASSOCIATION, as Trustee
By:			By:
	Authorized Officer			AS AUTHENTICATION AGENT
			By:
			Authorized Officer

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

THIS SECURITY MAY NOT BE TRANSFERRED OR EXCHANGED, NOR MAY ANY PURPORTED TRANSFER BE REGISTERED, EXCEPT (i) THIS SECURITY MAY BE TRANSFERRED IN WHOLE, AND APPROPRIATE REGISTRATION OF TRANSFER EFFECTED, IF SUCH TRANSFER IS BY CEDE & CO., AS NOMINEE FOR THE DEPOSITORY TRUST COMPANY (THE “DEPOSITARY”), TO THE DEPOSITARY, OR BY THE DEPOSITARY TO ANOTHER NOMINEE THEREOF, OR BY ANY NOMINEE OF THE DEPOSITARY TO ANY OTHER NOMINEE THEREOF, OR BY THE DEPOSITARY OR ANY NOMINEE THEREOF TO ANY SUCCESSOR SECURITIES DEPOSITARY OR

ANY NOMINEE THEREOF; AND (ii) THIS SECURITY MAY BE EXCHANGED FOR DEFINITIVE SECURITIES REGISTERED IN THE RESPECTIVE NAMES OF THE BENEFICIAL HOLDERS HEREOF, AND THEREAFTER SHALL BE TRANSFERABLE WITHOUT RESTRICTIONS IF: (A) THE DEPOSITARY, OR ANY SUCCESSOR SECURITIES DEPOSITARY, SHALL HAVE NOTIFIED THE COMPANY AND THE TRUSTEE THAT IT IS UNWILLING OR UNABLE TO CONTINUE TO ACT AS SECURITIES DEPOSITARY WITH RESPECT TO THE SECURITIES AND THE TRUSTEE SHALL NOT HAVE BEEN NOTIFIED BY THE COMPANY WITHIN NINETY (90) DAYS OF THE IDENTITY OF A SUCCESSOR SECURITIES DEPOSITARY WITH RESPECT TO THE SECURITIES; OR (B) THE COMPANY SHALL HAVE DELIVERED TO THE TRUSTEE A COMPANY ORDER TO THE EFFECT THAT THE SECURITIES SHALL BE SO EXCHANGEABLE ON AND AFTER A DATE SPECIFIED THEREIN.

FOR VALUE RECEIVED THE UNDERSIGNED HEREBY SELLS, assigns and transfers unto

[please insert social security or other identifying number of assignee]

[please print or typewrite name and address of assignee]

the within Security of PUBLIC SERVICE COMPANY OF COLORADO and does hereby irrevocably constitute and appoint                                          Attorney, to transfer said Security on the books of the within-mentioned 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 Security in every particular without alteration or enlargement or any change whatsoever.

SCHEDULE A

SUPPLEMENTAL INDENTURES

Date of Supplemental Indenture	Series of Bonds	Principal Amount Issued		Principal Amount Outstanding
November 1, 1993	Series No. 1	$	134,500,000	None
January 1, 1994	Series No. 2 due 2001	$	102,667,000	None
	and Series No. 2 due 2024	$	110,000,000	None
September 2, 1994 (Appointment of Successor Trustee)	None	None		None
May 1, 1996	Series No. 3	$	125,000,000	None
November 1, 1996	Series No. 4	$	250,000,000	$	100,000,000
February 1, 1997	Series No. 5	$	150,000,000	None
April 1, 1998	Series No. 6	$	250,000,000	None
August 15, 2002	Series No. 7	$	48,750,000	$	48,750,000
September 1, 2002	Series No. 8	$	600,000,000	None
September 15, 2002	Series No. 9	$	530,000,000	None
April 1, 2003	Series No. 10	$	600,000,000	$	600,000,000
March 1, 2003	Series No. 11	$	250,000,000	None
September 15, 2003	Series No. 12	$	250,000,000	$	250,000,000
May 1, 2003	Series No. 13	$	350,000,000	None
September 1, 2003	Series No. 14	$	300,000,000	$	300,000,000
September 1, 2003	Series No. 15	$	275,000,000	$	275,000,000
August 1, 2005	Series No. 16	$	129,500,000	$	129,500,000

EX-4.(B)(3)

Exhibit 4.(b)(3)

FORM OF SUPPLEMENTAL INDENTURE
(Senior Notes)

PUBLIC SERVICE COMPANY
OF COLORADO

TO

THE BANK OF NEW YORK TRUST COMPANY, N.A.,
as Trustee

SUPPLEMENTAL INDENTURE

Dated as of                     


Supplementing the Indenture
dated as of July 1, 1999

Establishing the Securities of Series         
designated           % Senior Notes due                           

THIS                      SUPPLEMENTAL INDENTURE, dated as of                         , is between PUBLIC SERVICE COMPANY OF COLORADO, a Colorado corporation (hereinafter called the “Issuer” or the “Company”), having its principal office at 1225 17th Street, Denver, Colorado 80202, and THE BANK OF NEW YORK TRUST COMPANY, N.A., as Trustee (hereinafter called the “Trustee”), having its principal corporate trust office at 101 Barclay Street, New York, New York 10286.

Recitals of the Issuer

The Issuer has heretofore executed and delivered an Indenture, dated as of July 1, 1999 (the “Original Indenture”, the Original Indenture, previously supplemented and as further supplemented by this supplemental indenture being hereinafter referred to as the “Indenture”), relating to the issuance at any time or from time to time of its Securities on terms to be specified at the time of issuance. Terms used and not otherwise defined herein shall (unless the context otherwise clearly requires) have the respective meanings given to them in the Original Indenture.

The Original Indenture provides in Article Three thereof that, prior to the issuance of Securities of any series, the form of such Securities and the terms applicable to such series shall be established in, or pursuant to, the authority granted in a resolution of the Board of Directors or established in one or more indentures supplemental thereto.

The Issuer desires by this supplemental indenture, among other things, to establish the form of the Securities of a series, to be titled         % Notes due                                  of the Issuer, and to establish the terms applicable to such series, pursuant to Sections 201, 301 and 901 of the Original Indenture.  The Issuer has duly authorized the execution and delivery of this supplemental indenture.

Article Nine of the Original Indenture provides that the Issuer, when authorized by a resolution of its Board of Directors, and the Trustee may from time to time and at any time amend the Indenture without the consent of Securityholders for certain purposes enumerated in Section 901 thereof, including the purposes set forth in subsection (7) of said Section 901.

The execution and delivery of this supplemental indenture by the parties hereto are in all respects authorized by the provisions of the Indenture.

All things necessary have been done to make this supplemental indenture a valid agreement of the Issuer, in accordance with its terms.

NOW, THEREFORE, THIS              SUPPLEMENTAL INDENTURE WITNESSETH:

For and in consideration of the premises, it is mutually covenanted and agreed, as follows:

ARTICLE I

Establishment of % Notes due

Section 1.01.          The title of the series of the Securities established by this supplemental indenture shall be         % Notes due                                      of the Issuer (hereinafter called the “Series        Notes”).

Section 1.02.          The Series        Notes shall be limited to [$                            ] in aggregate principal amount.

Section 1.03.          The Series        Notes may be issued in whole or in part as one or more Global Securities and The Depository Trust Company, or a nominee thereof, shall be the Depository for such Global Security or Global Securities.  The Depository for such Global Security or Global Securities representing Series        Notes may surrender one or more Global Securities representing Series        Notes in exchange in whole or in part for individual Series        Notes on such terms as are acceptable to the Issuer and such Depository and otherwise subject to the terms of the Indenture.

Section 1.04.          The principal of the Series        Notes shall be payable on                                   .

Section 1.05.          The Series        Notes shall bear interest at the rate of       % per annum and shall accrue from                           . The Interest Payment Dates shall be                          and                            in each year, commencing                               . The Regular Record Dates in respect of such Interest Payment Dates shall be                                  and                                in each year, respectively.

Section 1.06.          The Corporate Trust Office of The Bank of New York Trust Company, N.A. shall be the place at which the principal of the Series        Notes shall be payable.  Any interest thereon shall be paid as specified in Section 307 of the Original Indenture.

Section 1.07.          [Interest Payment Deferral Provisions, if any.]

Section 1.08.          [Optional Redemption Provisions, if any.]

Section 1.09.          [Mandatory Redemption Provisions, if any.]

Section 1.10.The Series        Notes shall be issued in denominations of [$              ] and any integral multiple thereof.

Section 1.11.          [Original Issue Discount Provisions, if any.]

Section 1.12.          [Additional Defaults, if any.]

Section 1.13.          Sections 1301 and 1302 of the Indenture shall be applicable to the Series        Notes.

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Section 1.14.          [Currency, if other than U.S. Dollars.]

Section 1.15.          [Additional Covenants, if any.]

Section 1.16.          The Issuer hereby appoints, or confirms the appointment of, The Bank of New York Trust Company, N.A. as the initial Trustee, Securities Registrar and Paying Agent, subject to the provisions of the Indenture with respect to resignation, removal and succession, and subject, further, to the right of the Issuer to appoint additional agents (including Paying Agents).

Section 1.17.          [Exceptions to Business Day Definition, if any.]

Section 1.18.          [Any Additional Terms.]

Section 1.19.          The Series        Notes shall be substantially in the form set forth in Exhibit A hereto, and shall have such further terms as are reflected in such form, subject to changes in the form thereof made by the Issuer and acceptable to the Trustee.

ARTICLE II

Miscellaneous

Section 2.01.          The recitals contained herein shall be taken as the statements of the Issuer, and the Trustee assumes no responsibility for the correctness of the same. The Trustee makes no representation as to the validity of this supplemental indenture. The Indenture, as supplemented by this supplemental indenture, is in all respects hereby adopted, ratified and confirmed.

Section 2.02.          This supplemental indenture may be executed in any number of counterparts, and on separate counterparts, each of which shall be an original; but such counterparts shall together constitute but one and the same instrument.

Section 2.03.          If any provision of this supplemental indenture limits, qualifies or conflicts with the duties imposed by any of Sections 310 to 317, inclusive, of the Trust Indenture Act of 1939, as amended by the Trust Indenture Reform Act of 1990, through operation of Section 318(c), such imposed duties shall control.

Section 2.04.          The Article headings herein are for convenience only and shall not affect the interpretation hereof.

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IN WITNESS WHEREOF, the parties hereto have caused this Second Supplemental Indenture to be duly executed as of the          day of                                   .

PUBLIC SERVICE COMPANY OF COLORADO
By:
	Name:
	Title:
THE BANK OF NEW YORK TRUST COMPANY, N.A.
By:
		Authorized Signatory

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EXHIBIT A

Form of       % Note due                         

[THIS SECURITY 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 SECURITIES REPRESENTED HEREBY, THIS GLOBAL SECURITY MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER NOMINEE OF THE DEPOSITARY OR BY THE DEPOSITARY OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITARY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITARY.

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITARY TRUST COMPANY, A NEW YORK CORPORATION (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 IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITARY 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 INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.]

PUBLIC SERVICE COMPANY OF COLORADO       % Note due                                         

Interest Rate:
Interest Payment Dates:
Regular Record Dates:
Original Interest Accrual Date:
Stated Maturity:
Registered No.	Principal Amount
CUSIP	$

PUBLIC SERVICE COMPANY OF COLORADO, a corporation duly organized and existing under the laws of the State of Colorado (herein called the “Company”, which term includes any successor corporation under the Indenture referred to below) promises to pay to                                or registered assigns the principal sum of                                                Dollars on                                            the Stated Maturity specified above.

1.Interest.

The Company promises to pay interest on the principal amount hereof at the Interest Rate per annum shown above from the Original Interest Accrual Date specified above, or from the most recent Interest Payment Date to which interest has been paid, semiannually in arrears, on the Interest Payment Dates specified above, in each year, commencing with the Interest Payment Date next succeeding the Original Interest Accrual Date specified above, until the principal hereof is paid or duly provided for. Interest will be computed on the basis of a 360-day year of twelve 30-day months.

2.Method of Payment.

The Company will pay interest so payable to the person who is the registered holder hereof at the close of business on the Regular Record Date for the next Interest Payment Date, except as otherwise provided in the Indenture and except that interest payable at Maturity will be paid to the person to whom principal is paid at Maturity. Payment of principal shall be made upon presentation hereof at the office of this Paying Agent. The Company will pay principal and interest in money of the United States that at the time of payment is legal tender for payment of public and private debts. The Company may pay principal and interest by check payable in such money. It may mail an interest check to the holder’s registered address.

3.Agents.

Initially, The Bank of New York Trust Company, N.A., 101 Barclay Street, Floor 21 West, New York, New York 10286, Attention: Corporate Trust Administration, will act as Paying Agent, and Securities Registrar. The Company may change the Paying Agent to provide for more than one such agent. The Company may appoint one or more Security Registers. The Company or any Affiliate may act in any such capacity. The Trustee may appoint one or more Authenticating Agents to authenticate the Securities.

4.Indenture.

The securities of this series (the “Securities”) have been issued under an Indenture dated as July 1, 1999 (the “Indenture”) between the Company and The Bank of New York Trust Company, N.A. (the “Trustee,” which term includes any successor trustee under the Indenture). The terms of the Securities include those stated in the Indenture and in the Supplemental Indenture creating the Securities and those made part of the Indenture by the Trust Indenture Act of 1939 (15 U.S. Code Sections 77aaa-77bbbb). Securityholders are referred to the Indenture, the Supplemental Indenture and the Act for a statement of such terms.

A-2

5.Redemption.

[This Security is not redeemable prior to maturity.] or [This Security is subject to redemption upon not less than 30 days’ notice by first class mail, in whole or in part from time to time on and after              at the option of the Company at a redemption price equal to                                 

In the event of redemption of this Security in part only, a new Security or Securities of this series for the unredeemed portion hereof will be issued in the name of the Holder hereof upon the cancellation hereof.]

6.[Notice of Redemption.

Notice of redemption will be mailed at least 30 days before the redemption date to the holder hereof at his address appearing on the Security Register.

A notice of redemption shall provide that it is subject to the occurrence of any event before the date fixed for such redemption as described in such notice (“Conditional Redemption”) and such notice of Conditional Redemption shall be of no effect unless all such conditions to the redemption have occurred before such date or have been waived by the Company.]

7.Denominations, Transfer, Exchange.

The Securities of this series are in registered form without coupons in denominations of                          and whole multiples of                     . The transfer of this Security may be registered and this Security may be exchanged as provided in the Indenture. The Securities Registrar may require a holder, among other things, to furnish appropriate endorsements and transfer documents and to pay any taxes and fees required by law or the Indenture. The Securities Registrar need not exchange or register the transfer of any Security of this series or portion thereof selected for redemption. Also, it need not exchange or register the transfer of any Security for a period of 15 days before a selection of Securities of this series to be redeemed.

8.Persons Deemed Owners.

The registered holder of a Security may be treated as its owner for all purposes.

9.Amendments and Waivers.

Subject to certain exceptions, the Indenture may be amended with the consent of the holders of a majority in outstanding principal amount of the Securities. Subject to certain exceptions, a default under the Indenture may be waived with the consent of the holders of a majority in outstanding principal amount of the Securities.

A-3

Without the consent of any Securityholder, the Indenture may be amended, among other things, to cure any ambiguity, omission, defect or inconsistency; to provide for assumption of Company obligations to Securityholders; or to make any change that does not materially adversely affect the rights of any Securityholder.

10.Restrictive Covenants.

The Securities are unsecured general obligations of the Company limited to [$                          ] principal amount. The Indenture does not limit the amount of debt the Company may issue thereunder or otherwise.

11.Successors.

When a successor assumes all the obligations of the Company under the Securities and the Indenture, the Company will be released from those obligations.

12.Defeasance Prior to Redemption or Maturity.

Subject to certain conditions, the Company at any time may terminate some or all of its obligations hereunder and the Indenture if the Company deposits with the Trustee money or U.S. Government Obligations for the payment of principal and interest hereon to redemption or maturity. U.S. Government Obligations are securities backed by the full faith and credit of the United States of America or certificates representing an ownership interest in such Obligations.

13.Defaults and Remedies.

If an Event of Default occurs and is continuing, the Trustee or the holders of at least 25% in principal amount of the outstanding Securities may declare the principal of all such Securities to be due and payable immediately.  Securityholders may not enforce the Indenture or the Securities except as provided in the Indenture. The Trustee may require indemnity satisfactory to it before it enforces the Indenture or the Securities. Subject to certain limitations, holders of a majority in principal amount of the Securities may direct the Trustee in its exercise of any trust or power. The Trustee may withhold from Securityholders notice of any continuing default (except a default in payment of principal or interest or any sinking fund installment) if it determines that withholding notice is in their interests. The Company must furnish annual compliance certificates to the Trustee.

14.Trustee Dealings with Company.

The Bank of New York Trust Company, N.A., the Trustee under the Indenture, in its individual or any other capacity, may make loans to, accept deposits from, and perform services for the Company or its Affiliates, and may otherwise deal with the Company or its Affiliates, as if it were not Trustee.

A-4

15.No Recourse Against Others.

A director, officer, employee or stockholder, as such, of the Company shall not have any liability for any obligations of the Company under the Securities or the Indenture or for any claim based on, in respect of or by reason of such obligations or their creation. Each Securityholder by accepting a Security waives and releases all such liability. The waiver and release are part of the consideration for the issue of the Securities.

16.Authentication.

This Security shall not be valid for any purpose and shall not be entitled to any benefit under the Indenture until authenticated by a manual signature of the Trustee or any Authenticating Agent.

17.Abbreviations.

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

The Company will furnish to any Securityholder upon written request and without charge a copy of the Indenture, including the Supplemental Indenture which contains the text of this Security in larger type. Requests may be made to: Public Service Company of Colorado, 1225 17th Street, Denver, Colorado, 80202 attention: Corporate Secretary.

A-5

		PUBLIC SERVICE COMPANY OF COLORADO
		By:
			Name:
			Title:
[corporate seal]
Attest:
	Name:
	Title:

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

	THE BANK OF NEW YORK TRUST COMPANY, N.A., as Trustee
	By:
		Authorized Signatory
Dated:

A-6

ASSIGNMENT FORM

To assign this Security, fill in the form below:

I or we assign and transfer this Security to:

(Insert assignee’s social security or tax I.D. no.)

(Print or type assignee’s name, address and zip code)

and irrevocably appoint                                          agent to transfer this Security on the books of the Company. The agent may substitute another to act for him.

Date: Your Signature:

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

A-7

EX-5

Exhibit 5

NEW YORK WASHINGTON, D.C. ALBANY BOSTON CHICAGO HARTFORD HOUSTON JACKSONVILLE LOS ANGELES SAN FRANCISCO 125 WEST 55TH STREET NEW YORK, NY 10019-5389 (212) 424-8000 FACSIMILE: (212) 424-8500 LONDON A MULTINATIONAL
PARTNERSHIP PARIS BRUSSELS JOHANNESBURG (PTY) LTD. MOSCOW RIYADH AFFILIATED OFFICE ALMATY BEIJING

March 19, 2007

Public Service Company of Colorado

1225 17th Street

Denver, Colorado 80202

Dear Ladies and Gentlemen:

We have acted as counsel to Public Service Company of Colorado, a Colorado corporation (the “Company”), in connection with the preparation and filing of a Registration Statement on Form S-3 (the “Registration Statement”), to be filed with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended (the “Securities Act”). The Registration Statement relates to the proposed issuance and sale of up to $1,200,000,000 in aggregate principal amount of (i) First Mortgage Bonds of the Company (the “Bonds”) to be issued pursuant to the Indenture, dated as of October 1, 1993, between the Company and U.S. Bank Trust National Association (formerly First Trust of New York, National Association), as successor trustee (the “Mortgage Trustee”) as supplemented and to be supplemented by various supplemental indentures (as supplemented, the “Mortgage Indenture”), including one or more supplemental indentures to be entered into by the Company and the Mortgage Trustee relating to the Bonds registered under the Registration Statement and (ii) Senior Debt Securities of the Company (the “Notes” and, collectively with the Bonds, the “Securities”) to be issued pursuant to the Indenture, dated as of July 1, 1999, between the Company and The Bank of New York Trust Company, N.A., as trustee (the “Note Trustee”), as supplemented and to be supplemented by various supplemental indentures (as supplemented, the “Note Indenture”), including one or more supplemental indentures to be entered into by the Company and the Note Trustee relating to the Notes registered under the Registration Statement.  The Securities may be issued in one or more series from time to time pursuant to the provisions of Rule 415 under the Securities Act.

In connection with this opinion, we have examined a copy of the Registration Statement and such corporate records, certificates and other documents as we have considered necessary for the purposes of this opinion. In such examination, we have assumed the genuineness of all

signatures, the authenticity of all documents submitted to us as originals, the conformity to the original documents of all documents submitted to us as copies and the authenticity of the originals of such latter documents.  We have also assumed the regularity of all corporate proceedings.  As to any facts material to our opinion, we have, when relevant facts were not independently established, relied upon the aforesaid records, certificates and documents.

Based upon and subject to the foregoing examination, and subject to the further qualifications and limitations set forth below, we are of the opinion that:

1.             The Company is a corporation validly existing and in good standing under the laws of the State of Colorado.

2.             When (i) the Registration Statement, as finally amended (including any necessary post-effective amendments), has become effective under the Securities Act; (ii) a prospectus supplement with respect to a particular series of Securities has been filed with the Commission in compliance with the Securities Act and the rules and regulations thereunder; and (iii) all orders, consents or other authorizations of the Colorado Public Utilities Commission required for the valid issuance and sale of the Securities of such series have been obtained, no further authorization, consent or approval by any regulatory authority will be required for the valid issuance and sale of such series of Securities.

3.             When (i) a purchase contract setting forth the price and other terms and conditions relating to the issue and sale of a particular series of Securities (a “Purchase Agreement”) has been approved by the Company in accordance with the resolutions adopted by the Board of Directors relating to the Registration Statement and (ii) a supplemental indenture to the Mortgage Indenture or the Note Indenture, as applicable, has been duly executed and delivered by the Company and the Mortgage Trustee or the Note Trustee, as applicable, establishing the terms and conditions of a particular series of Securities, such series of Securities will have been duly authorized by the Company.

4.             Upon the execution and filing with the Mortgage Trustee or the Note Trustee, as applicable, of the proper certificates with respect to the Securities of a particular series, the Securities of such series will be issuable under the terms of the Mortgage Indenture or the Note Indenture, as applicable.

5.             When (i) such series of Securities have been duly executed, authenticated and delivered in accordance with the corporate and governmental authorizations, the Purchase Agreement, the supplemental indenture with respect thereto and the certificates referred to in paragraph 4 above, (ii) with respect to the Bonds, such supplemental indenture shall have been duly recorded, and (iii) the purchase price specified in the Purchase Agreement for such series of Securities shall have been received by the Company, the Securities of such series will be legally issued and binding obligations of the Company and will be entitled to the benefits of the Mortgage Indenture or the Note Indenture, as applicable, on a parity with the securities of other series which may be thereafter issued pursuant to the terms of the Mortgage Indenture or the Note Indenture, as the case may be (subject to bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance or other similar laws affecting the enforcement of creditors’ rights generally and to general principles of equity, regardless of whether such principles are

2

considered in a proceeding in equity or at law) and in the case of the Bonds, state laws that affect the enforcement of certain remedial provisions of the Mortgage Indenture; provided, however, that such state laws will not, in our opinion, render the remedies afforded by the Mortgage Indenture inadequate for the practical realization of the benefit of the security provided thereby.

We express no opinion as to the application of the securities or blue sky laws of the several states to the sale of the securities to be registered pursuant to the Registration Statement.

Our opinion expressed above is limited to the laws of the State of New York and the State of Colorado, and the federal laws of the United States of America.

We hereby consent to the filing of this opinion as an exhibit to the Registration Statement and the use of our name under the heading “Legal Opinions” in the prospectus forming a part of the Registration Statement.  In giving such consent, we do not thereby concede that we are within the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Commission thereunder.

Very truly yours,

/s/ LeBoeuf, Lamb, Greene & MacRae LLP

3

EX-12

Exhibit 12

PUBLIC SERVICE COMPANY OF COLORADO

STATEMENT OF COMPUTATION OF

RATIO OF CONSOLIDATED EARNINGS TO CONSOLIDATED FIXED CHARGES

(Thousands of Dollars)

	Year ended Dec. 31,
	2006		2005		2004		2003		2002
Earnings as defined:
Pretax income	$	323,159	$	281,657	$	290,861	$	316,144	$	393,366
Add: Fixed Charges	264,672		263,516		266,231		270,051		244,269
Earnings as defined	$	587,831	$	545,173	$	557,092	$	586,195	$	637,635
Fixed charges:
Interest charges	$	264,672	$	263,516	$	266,231	$	262,679	$	229,525
Distributions on redeemable preferred securities of subsidiary trust	—		—		—		7,372		14,744
Total fixed charges	$	264,672	$	263,516	$	266,231	$	270,051	$	244,269
Ratio of earnings to fixed charges	2.2		2.1		2.1		2.2		2.6

EX-23.(B)

Exhibit 23(b)

CONSENT OF RYLEY CARLOCK & APPLEWHITE

We hereby consent to the reference to us under the captions “Description of the First Mortgage Bonds - Security - Lien of the Mortgage Indenture” and “Legal Opinions” in the prospectus constituting a part of the Registration Statement on Form S-3 of Public Service Company of Colorado filed with the Securities and Exchange Commission on the date hereof.  In giving such consent, we do not hereby admit that we are included in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Securities and Exchange Commission promulgated thereunder.

/s/ RYLEY CARLOCK & APPLEWHITE

Denver, Colorado
March 19, 2007

EX-23.(C)

Exhibit 23(c)

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in this Registration Statement on Form S-3 of our report dated February 22, 2007, (which report expresses an unqualified opinion and includes an explanatory paragraph relating to the adoption of Statement of Financial Accounting Standards No. 158, “Employers’ Accounting for Defined Benefit Pension and Other Postretirement Plans”) relating to the consolidated financial statements and financial statement schedule of Public Service Company of Colorado, appearing in the Annual Report on Form 10-K of Public Service Company of Colorado for the year ended December 31, 2006, and to the reference to us under the heading “Experts” in the Prospectus, which is part of this Registration Statement.

/s/ DELOITTE & TOUCHE LLP

Minneapolis, Minnesota

March 19, 2007

EX-24

Exhibit 24

POWER OF ATTORNEY

WHEREAS, Public Service Company of Colorado, a Colorado corporation (the “Company”), is about to file with the Securities and Exchange Commission, under the provisions of the Securities Act of 1933, as amended, a registration statement and/or post-effective amendments which may consist of one or more registration statements on Form S-3 relating to the issuance and sale from time to time of up to $1.2 billion principal amount of debt securities; and

WHEREAS, each of the undersigned holds the office or offices in the Company herein below set forth below his/her name, respectively.

NOW, THEREFORE, each of the undersigned hereby constitutes and appoints Benjamin G.S. Fowke, Gary R. Johnson and Richard C. Kelly and each of them individually, his/her attorney, with full power to act for him/her and in his/her name, place and stead, to sign his/her name in the capacity or capacities set forth below to one or more registration statements on Form S-3 (or any other appropriate form) or post-effective amendments to registration statements on Form S-3, relating to the issuance and sale of up to $1.2 billion principal amount of debt securities and to any and all amendments (including any post-effective amendments) to such registration statements, and hereby ratifies and confirms all that said attorney may or shall lawfully do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, the undersigned have hereunto set their hands this 20th day of September, 2006.

/s/ Patricia K. Vincent	/s/ Richard C. Kelly
Patricia K. Vincent President, Chief Executive Officer and Director (Principal Executive Officer)	Richard C. Kelly Chairman and Director
/s/ Gary R. Johnson	/s/ Teresa S. Madden
Gary R. Johnson Vice President, General Counsel and Director	Teresa S. Madden Vice President and Controller (Principal Accounting Officer)
/s/ Benjamin G.S. Fowke III	/s/ Paul J. Bonavia
Benjamin G.S. Fowke III Vice President and Chief Financial Officer and Director(Principal Financial Officer)	Paul J. Bonavia Director
/s/ Cynthia L. Lesher
Cynthia L. Lesher Director

EX-25.(A)

Exhibit 25(a)

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM T-1

STATEMENT OF ELIGIBILITY UNDER
THE TRUST INDENTURE ACT OF 1939 OF A
CORPORATION DESIGNATED TO ACT AS TRUSTEE
Check if an Application to Determine Eligibility of
a Trustee Pursuant to Section 305(b)(2)o

U.S. BANK TRUST NATIONAL ASSOCIATION
(Exact name of Trustee as specified in its charter)

41-1973763
I.R.S. Employer Identification No.

300 East Delaware Avenue, 8th Floor
Wilmington, Delaware	19801
(Address of principal executive offices)	(Zip Code)

K. Wendy Kumar
U.S. Bank Trust National Association
100 Wall Street, Suite 1600
New York, NY 10005
Telephone (212) 361-2535
(Name, address and telephone number of agent for service)

Public Service Company of Colorado
(Exact name of obligor as specified in its charter)

Colorado	84-0296600
(State or other jurisdiction of	(I. R. S. Employer
incorporation or organization)	Identification No.)

1225 17th Street
Denver, CO	80202-5533
(Address of principal executive offices)	(Zip Code)

First Mortgage Bonds

FORM T-1

Item 1.GENERAL INFORMATION.  Furnish the following information as to the Trustee.

a)Name and address of each examining or supervising authority to which it is subject.

Comptroller of the Currency

Washington, D.C.

b)Whether it is authorized to exercise corporate trust powers.

Yes

Item 2.AFFILIATIONS WITH OBLIGOR.  If the obligor is an affiliate of the Trustee, describe each such affiliation.

None

USE ONE OF FOLLOWING RESPONSES ONLY

Items 3-15Not applicable because, to the best of Trustee’s knowledge, the Trustee is not a trustee under any other indenture under which any other securities or certificates of interest or participation in any other securities of the obligor are outstanding and there is not, nor has there been, a default with respect to securities issued under this indenture.

Items 3-15The Trustee is a Trustee under other Indentures under which securities issued by the obligor are outstanding.  There is not and there has not been a default with respect to the securities outstanding under other such Indentures.

Item 16.LIST OF EXHIBITS:  List below all exhibits filed as a part of this statement of eligibility and qualification.

1.A copy of the Articles of Association of the Trustee now in effect, incorporated herein by reference to Exhibit 1 of Form T-1, Document 6 of Registration No. 333-84320.

2A copy of the certificate of authority of the Trustee to commence business, incorporated herein by reference to Exhibit 2 of Form T-1, Document 6 of Registration No. 333-84320.

3.A copy of the certificate of authority of the Trustee to exercise corporate trust powers, incorporated herein by reference to Exhibit 3 of Form T-1, Document 6 of Registration No. 333-84320.

4.A copy of the existing bylaws of the Trustee, as now in effect, incorporated herein by reference to Exhibit 4 of Form T-1, Document 6 of Registration No. 333-113995.

5.Not applicable.

6.The consent of the Trustee required by Section 321(b) of the Trust Indenture Act of 1939, incorporated herein by reference to Exhibit 6 of Form T-1, Document 6 of Registration No. 333-84320.

7.Report of Condition of the Trustee as of June 30, 2006, published pursuant to law or the requirements of its supervising or examining authority, attached as Exhibit 7.

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8.Not applicable.

9.Not applicable.

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SIGNATURE

Pursuant to the requirements of the Trust Indenture Act of 1939, as amended, the Trustee, U.S. BANK TRUST NATIONAL ASSOCIATION, a national banking association organized and existing under the laws of the United States of America, has duly caused this statement of eligibility and qualification to be signed on its behalf by the undersigned, thereunto duly authorized, all in the City of New York, State of New York on the 1st day of November, 2006.

U.S. BANK TRUST NATIONAL ASSOCIATION
By:	/s/ K. Wendy Kumar
Name:	K. Wendy Kumar
Title:	Vice President

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Exhibit 7
U.S. Bank Trust National Association
Statement of Financial Condition”
As of 9/30/2006

($000’s)

	9/30/2006
Assets
Cash and Due From Depository Institutions	$	6,436,856
Securities	39,245,651
Federal Funds	3,475,844
Loans & Lease Financing Receivables	141,382,736
Fixed Assets	2,629,727
Intangible Assets	11,923,005
Other Assets	10,799,396
Total Assets	$	215,893,215
Liabilities
Deposits	$	133,945,028
Fed Funds	12,987,134
Treasury Demand Notes	0
Trading Liabilities	166,479
Other Borrowed Money	31,884,451
Acceptances	0
Subordinated Notes and Debentures	6,909,696
Other Liabilities	7,674,530
Total Liabilities	$	193,567,318
Equity
Minority Interest in Subsidiaries	$	1,044,165
Common and Preferred Stock	18,200
Surplus	11,977,237
Undivided Profits	9,286,295
Total Equity Capital	$	22,325,897
Total Liabilities and Equity Capital	$	215,893,215

To the best of the undersigned’s determination, as of the date hereof, the above financial information is true and correct.

U.S. Bank National Association
By:	/s/ K. Wendy Kumer
	Vice President
Date: February 20, 2007

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EX-25.(B)

Exhibit 25(b)

FORM T-1

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C.  20549

STATEMENT OF ELIGIBILITY
UNDER THE TRUST INDENTURE ACT OF 1939 OF A
CORPORATION DESIGNATED TO ACT AS TRUSTEE

CHECK IF AN APPLICATION TO DETERMINE
ELIGIBILITY OF A TRUSTEE PURSUANT TO
SECTION 305(b)(2)           o

THE BANK OF NEW YORK TRUST COMPANY, N.A.
(Exact name of trustee as specified in its charter)

(State of incorporation
if not a U.S. national bank) 95-3571558
(I.R.S. employer
identification no.)

700 South Flower Street
Suite 500
Los Angeles, California	90017
(Address of principal executive offices)	(Zip code)

PUBLIC SERVICE COMPANY OF COLORADO

(Exact name of obligor as specified in its charter)

COLORADO	84-0296600
(State or other jurisdiction of	(I.R.S. employer
incorporation or organization)	identification no.)

1225 17th Street
Denver, CO	80202-5533
(Address of principal executive offices)	(Zip code)

Senior Debt Securities
(Title of the indenture securities)

1.General information.  Furnish the following information as to the trustee:

(a)Name and address of each examining or supervising authority to which it is subject.

Name	Address
Comptroller of the Currency United States Department of the Treasury	Washington, D.C. 20219
Federal Reserve Bank	San Francisco, California 94105
Federal Deposit Insurance Corporation	Washington, D.C. 20429

(b)Whether it is authorized to exercise corporate trust powers.

Yes.

2.Affiliations with Obligor.

If the obligor is an affiliate of the trustee, describe each such affiliation.

None.

16.List of Exhibits.

Exhibits identified in parentheses below, on file with the Commission, are incorporated herein by reference as an exhibit hereto, pursuant to Rule 7a-29 under the Trust Indenture Act of 1939 (the “Act”) and 17 C.F.R. 229.10(d).

1.A copy of the articles of association of The Bank of New York Trust Company, N.A. (Exhibit 1 to Form T-1 filed with Registration Statement No. 333-121948).

2.A copy of certificate of authority of the trustee to commence business. (Exhibit 2 to Form T-1 filed with Registration Statement No. 333-121948).

3.  A copy of the authorization of the trustee to exercise corporate trust powers. (Exhibit 3 to Form T-1 filed with Registration Statement No. 333-121948).

4.A copy of the existing by-laws of the trustee. (Exhibit 4 to Form T-1 filed with Registration Statement No. 333-121948).

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6.The consent of the trustee required by Section 321(b) of the Act. (Exhibit 6 to Form T-1 filed with Registration Statement No. 333-121948).

7.A copy of the latest report of condition of the Trustee published pursuant to law or to the requirements of its supervising or examining authority.

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SIGNATURE

Pursuant to the requirements of the Act, the trustee, The Bank of New York Trust Company, N.A., a banking association organized and existing under the laws of the United States of America, has duly caused this statement of eligibility to be signed on its behalf by the undersigned, thereunto duly authorized, all in The City of Los Angeles, and State of California, on the 22nd day of February, 2007.

THE BANK OF NEW YORK TRUST COMPANY, N.A
By:	/S/ Sandeé Parks
Name:		Sandeé Parks
Title:		Vice President

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EXHIBIT 7

Consolidated Report of Condition of
THE BANK OF NEW YORK TRUST COMPANY, N.A.
of 700 South Flower Street, Suite 200, Los Angeles, CA 90017

At the close of business December 31, 2006, published in accordance with Federal regulatory authority instructions.

	Dollar Amounts in Thousands
ASSETS
Cash and balances due from depository institutions:
Noninterest-bearing balances  and currency and coin	10,020
Interest-bearing balances	0
Securities:
Held-to-maturity securities	56
Available-for-sale securities	64,801
Federal funds sold and securities purchased under agreements to resell:
Federal funds sold	49,900
Securities purchased under agreements to resell	40,000
Loans and lease financing receivables:
Loans and leases held for sale	0
Loans and leases,  net of unearned income.	0
LESS: Allowance for loan and  lease losses	0
Loans and leases, net of unearned  income and allowance	0
Trading assets	0
Premises and fixed assets (including capitalized leases)	5,051
Other real estate owned	0
Investments in unconsolidated subsidiaries and associated companies	0
Not applicable
Intangible assets:
Goodwill	889,415
Other Intangible Assets	277,086
Other assets	113,348
Total assets	$	1,449,677
LIABILITIES
Deposits:
In domestic offices	2,517
Noninterest-bearing	2,517
Interest-bearing	0
Not applicable
Federal funds purchased and securities sold under agreements to repurchase:
Federal funds purchased	0
Securities sold under agreements to repurchase	0
Trading liabilities	0
Other borrowed money:
(includes mortgage indebtedness and obligations under capitalized leases)	58,000
Not applicable
Not applicable
Subordinated notes and debentures	0
Other liabilities	127,233
Total liabilities	187,750
Minority interest in consolidated subsidiaries	0
EQUITY CAPITAL
Perpetual preferred stock and related surplus	0
Common stock	1,000
Surplus (exclude all surplus related to preferred stock)	1,121,520
Retained earnings	139,524
Accumulated other comprehensive income	-117
Other equity capital components	0
Total equity capital	1,261,927
Total liabilities, minority interest, and equity capital (sum of items 21, 22, and 28)	1,449,677

1

I, William J. Winkelmann, Vice President of the above-named bank do hereby declare that the Reports of Condition and Income (including the supporting schedules) for this report date have been prepared in conformance with the instructions issued by the appropriate Federal regulatory authority and are true to the best of my knowledge and belief.

William J. Winkelmann  )    Vice President

We, the undersigned directors (trustees), attest to the correctness of the Report of Condition (including the supporting schedules) for this report date and declare that it has been examined by us and to the best of our knowledge and belief has been prepared in conformance with the instructions issued by the appropriate Federal regulatory authority and is true and correct.

Michael K. Klugman, President	)
Michael F. McFadden, MD	)	Directors (Trustees)
Frank P. Sulzberger, Vice President	)

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