EXHIBIT 5(b)

                            [Letterhead of Jones Day]



                                 April 14, 2003


Public Service Company of Colorado
1225 17th Street
Denver, Colorado 80202

                       Re: Registration Statement on Form S-3 for Senior Debt
                           Securities of Public Service Company of Colorado

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 $800,000,000 in
aggregate principal amount of Senior Debt Securities of the Company (the
"Bonds") to be issued pursuant to the Indenture, dated as of July 1, 1999,
between the Company and The Bank of New York, as trustee (the "Trustee"), as
supplemented and to be supplemented by various supplemental indentures (as
supplemented, the "Indenture"), including one or more supplemental indentures to
be entered into by the Company and the Trustee relating to the Bonds registered
under the Registration Statement. The Bonds will be issued in one or more series
from time to time pursuant to the provisions of Rule 415 under the Securities
Act.

         In rendering this opinion, we have examined such documents and records,
including an examination of originals or copies certified or otherwise
identified to our satisfaction, and matters of law as we have deemed necessary
for purposes of this opinion.

         Based upon the foregoing and subject to the assumptions, qualifications
and limitations stated herein, we are of the opinion that when (i) the
Registration Statement has become effective under the Securities Act, (ii) a
purchase contract setting forth the price and other terms and conditions
relating to the issue of a particular series of Bonds (a "Purchase Agreement")
shall have been duly authorized, executed and delivered by the Company, (iii)
such series of Bonds shall have been duly executed by the Company, authenticated
by the Trustee in accordance with the Indenture and delivered in accordance with
the terms of the Purchase Agreement, (iv) the purchase price specified in the
Purchase Agreement for such series of Bonds shall have been received by the
Company and (v) the order or orders of The Public Utilities Commission of the
State of Colorado required for the valid issuance and sale of a particular
series of Bonds shall have been obtained, the Bonds of such series will be
validly issued by the Company and will




constitute valid and binding obligations of the Company enforceable in
accordance with their terms and entitled to the benefits of the Indenture.

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

         Our opinions with respect to the enforceability of, and the obligations
referred to in, the Bonds are subject to (i) bankruptcy, insolvency, fraudulent
transfer or conveyance, reorganization, voidable preference, moratorium or other
similar laws of general applicability relating to or affecting creditors' rights
and remedies generally and (ii) general principles of equity, regardless of
whether such enforceability is considered in a proceeding at equity or at law,
including, without limitation, concepts of materiality, reasonableness, good
faith and fair dealing, and the availability of the remedy of specific
performance or injunctive relief, and (iii) the fact that determination of
damages and entitlement for reimbursement for costs and expenses (including
without limitation, attorneys' fees) is within the judicial discretion of the
court before which such relief is requested.

         Our examination of matters of law in connection with the opinions
expressed herein has been limited to, and accordingly our opinions herein are
limited to, the laws of the State of New York. We express no opinion with
respect to any other law of the State of New York or any other jurisdiction.

         We hereby consent to the filing of this opinion as Exhibit 5(b) to the
Registration Statement and to the reference to us with respect to this opinion
under the caption "Legal Matters" in the prospectus constituting a part of the
Registration Statement. In giving such consent, we do not thereby 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 Commission
promulgated thereunder.

                                                     Very truly yours,


                                                     /s/ JONES DAY