SECURITIES AND EXCHANGE COMMISSION
                                Washington, D. C.
                                   FORM U-6B-2
                           Certificate of Notification

      Filed by a registered  holding company or subsidiary  thereof  pursuant to
Rule U-20-(d) [Reg.  Section  250.20,  paragraph  36,652] or U-47 [Reg.  Section
250.47,  paragraph  36,620] adopted under the Public Utility Holding Company Act
of 1935

Certificate is filed by: Public Service Company of Colorado (the "Company") on
                  its own behalf and on the behalf of PSCO Capital Trust I (the
                  "Trust")


      This  certificate  is notice  that the above  named  company  has  issued,
renewed or guaranteed the security or securities  described  herein which issue,
renewal or guaranty was exempted from the  provisions of Section 6(a) of the Act
and was neither  the subject of a  declaration  or  application  on Form U-1 nor
included  within  the  exemption  provided  by Rule U-48 [Reg.  Section  250.48,
paragraph 36,621].

 1. Type of the security or securities:
    a) 7.60% Trust Originated Preferred Securities ("Preferred") and Common
       Securities ("Common")
    b) 7.60% Deferrable Interest Subordinated Debentures
    c) Guarantee  for  benefit of holders of  preferred  securities  and common
       securities
2.  Issue, renewal or guaranty:
    a)  issue
    b)  issue
    c)  guaranty
3.  Principal amount of each security:
    a)  $194,000,000 (Preferred); $6,000,000 (Common)
    b)  $200,000,000
    c)  guarantee of payment
 4. Rate of interest per annum of each security:
    a)  7.60%
    b)  7.60%
    c)  Not applicable
5.  Date of issue, renewal or guaranty of each security:
    a) May 11, 1998
    b) May 11, 1998
    c) May 11, 1998
6.  If renewal of security, give date of original issue: Not applicable.
7.  Date of maturity of each security:
    a)  June 30, 2038
    b)  June 30, 2038
    c)  June 30, 2038




 8. Name of the person to whom each security was issued, renewed or guaranteed:
    a)  Public - investors (Preferred); the Company (Common)
    b)  The Trust
    c)  Bank of New York as trustee
 9. Collateral given with each security, if any:
    a)  none
    b)  none
    c)  none
 10. Consideration received for each security:
    a)  $194,000,000 (Preferred); $6,000,000 (Common)
    b)  $200,000,000
    c)  none
 11. Application of proceeds of each security:
    a)  Net proceeds used by the Trust to purchase 7.60% Deferrable Interest
        Subordinated Debentures from the Company.
    b)  Net proceeds used by the Company to redeem all its outstanding shares of
        preferred stock of the Company.
    c)  not applicable
 12. Indicate by a check after the applicable statement below whether the issue,
     renewal or guaranty of each security was exempt from the provisions of
     Section 6(a) because of:
    a) the provisions contained in the first sentence of Section 6(b): 
       Not applicable
    b) the provisions contained in the fourth sentence of Section 6(b):
       Not applicable
    c) the provisions contained in any rule of the commission other than Rule
       U-48: All three securities.
- --------------------------------------------------------------------------------

 13. If the security or  securities  were exempt from the  provisions of Section
   6(a) by virtue of the first sentence of Section 6(b),  give the figures which
   indicate that the security or securities  aggregate  (together with all other
   than  outstanding  notes and  drafts of a  maturity  of nine  months or less,
   exclusive  of days of  grace,  as to  which  such  company  is  primarily  or
   secondarily  liable) not more than 5 per centum of the  principal  amount and
   par value of the other securities of such company then  outstanding.  (Demand
   notes,  regardless  of how  long  they may have  been  outstanding,  shall be
   considered  as  maturing  in not more than nine  months for  purposes  of the
   exemption  from  Section  6(a) of the Act  granted by the first  sentence  of
   Section 6(b)).
       Not applicable.
 14. If the security or  securities  are exempt from the  provisions  of Section
   6(a)  because  of the fourth  sentence  of Section  6(b),  name the  security
   outstanding  on January 1, 1935,  pursuant to the terms of which the security
   or securities herein described have been issued.
              Not applicable.
 15. If the security or  securities  are exempt from the  provisions  of Section
   6(a) because of any rule of the Commission other than Rule U-48 [Reg. Section
   250.48,  paragraph  36,621]  designate  the rule  under  which  exemption  is
   claimed.
      Rule 52




                                    Public Service Company of Colorado


                                    By:  /s/ James D. Steinhilper
                                        --------------------------
                                          James D. Steinhilper
                                          Treasurer


Date: May 21, 1998