EXHIBIT 5.1

                [LETTERHEAD OF TAFT, STETTINIUS & HOLLISTER LLP]





                                 October 9, 2001



PSI Energy, Inc.
1000 East Main Street
Plainfield, Indiana 46168

Dear Sir or Madam:

     In connection with the registration under the Securities Act of 1933 (the
"Act") of $325 million principal amount of First Mortgage Bonds Series EEE,
6.65%, due June 15, 2006 (the "New Bonds") of PSI Energy, Inc., an Indiana
corporation (the "Company"), to be issued in exchange for the Company's
outstanding First Mortgage Bonds Series EEE, 6.65%, due June 15, 2006 (the "Old
Bonds") pursuant to (i) the Indenture dated September 1, 1939 as amended through
the Fifty-third Supplemental Indenture dated June 15, 2001 (the "Indenture")
between the Company and LaSalle Bank National Association, as trustee (the
"Trustee"), and (ii) the Registration Rights Agreement dated as of June 22, 2001
(the "Registration Rights Agreement") by and among the Company and Merrill
Lynch, Pierce, Fenner & Smith Incorporated, ABN AMRO Rothschild LLC, and J.P.
Morgan Securities, Inc., we, as your counsel, have examined such corporate
records, certificates and other documents, and such questions of law, as we have
considered necessary or appropriate for the purposes of this opinion.

     Upon the basis of such examination, we advise you that, in our opinion, the
New Bonds have been duly authorized by the Company; and when the Securities and
Exchange Commission declares the Company's Registration Statement on Form S-4
effective and the New Bonds have been duly executed, authenticated, issued and
delivered in exchange for the Old Bonds in accordance with the terms of the
Registration Rights Agreement and the Indenture, the New Bonds will be legally
issued, fully paid and nonassessable and the binding obligations of the Company
enforceable in accordance with their terms, subject to bankruptcy, insolvency,
fraudulent transfer, reorganization, moratorium and similar laws of general
applicability relating to or affecting creditors' rights and to general equity
principles.

     The foregoing opinion is limited to the federal laws of the United States
of America, and the Indiana General Corporation Law, and we are expressing no
opinion as to the effect of the laws of any other jurisdiction.




     In connection with the foregoing, we have assumed that at the time of the
issuance and delivery of the New Bonds there will not have occurred any change
in law affecting the validity, legally binding character or enforceability of
the New Bonds and that the issuance and delivery of the New Bonds, all of the
terms of the New Bonds and the performance by the Company of its obligations
thereunder will comply with applicable law and with each requirement or
restriction imposed by any court or governmental body having jurisdiction over
the Company and will not result in a default under or a breach of any agreement
or instrument then binding upon the Company.

     In rendering the foregoing opinion, we have relied as to certain matters on
information obtained from public officials, officers of the Company and other
sources believed by us to be responsible, and we have assumed (i) that the
Indenture has been duly authorized, executed and delivered by the Trustee, (ii)
that the New Bonds will conform to the form thereof set forth in the Indenture,
(iii) that the Trustee's certificates of authentication of the New Bonds will be
manually signed by one of the Trustee's authorized officers and (iv) that the
signatures on all documents examined by us are genuine, assumptions which we
have not independently verified.

     We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to us under the heading "Legal
Matters" in the Prospectus. In giving such consent, we do not hereby admit that
we are in the category of persons whose consent is required under Section 7 of
the Act.

                                       Very truly yours,


                                       /s/ TAFT, STETTINIUS & HOLLISTER LLP