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                                                                       EXHIBIT 5

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   BRUSSELS  CINCINNATI  CLEVELAND  COLUMBUS  DAYTON  NEW YORK  WASHINGTON, D.C.


September 17, 2004

The Union Light, Heat and Power Company
139 East Fourth Street
Cincinnati, Ohio 45202

Ladies and Gentlemen:

We have acted as counsel to The Union Light, Heat and Power Company, a Kentucky
corporation (the "COMPANY"), in connection with the filing with the Securities
and Exchange Commission of a Registration Statement on Form S-3 (the
"REGISTRATION STATEMENT") pursuant to the Securities Act of 1933, as amended
(the "SECURITIES ACT"), with respect to the proposed issuance and sale from time
to time pursuant to Rule 415 under the Securities Act of unsecured debt
securities of the Company (the "SECURITIES") with an aggregate offering price of
up to $45 million. The offering of the Securities will be made as set forth in
the prospectus contained in the Registration Statement, as supplemented by one
or more supplements to the prospectus.

For purposes of this opinion, we have examined the originals, or copies
identified to our satisfaction, of such corporate records of the Company,
certificates of public officials, officers of the Company and other persons, and
such other documents, agreements and instruments, as we have deemed relevant. We
have assumed the following: (i) the authenticity of original documents and the
genuineness of all signatures; (ii) the conformity to the originals of all
documents submitted to us as copies; and (iii) the truth, accuracy and
completeness of the information, representations and warranties contained in the
records, documents, agreements, instruments and certificates we have reviewed.

Based upon the foregoing, it is our opinion that when the Indenture in the form
included as an exhibit to the Registration Statement (the "INDENTURE") has been
duly executed and delivered by the Company and the trustee named in the
Indenture and the terms of each specific series of Securities have been
established in accordance with the Indenture and any supplemental indenture and
duly approved and authorized (including any necessary regulatory approvals), and
the Securities of each series have been duly executed by the Company and
authenticated as provided in the Indenture and any supplemental indenture and
duly paid for and delivered in the manner described in the Registration
Statement, including the prospectus and any prospectus supplement relating to
such series, the Securities will be valid and legally binding obligations of the
Company, enforceable against the Company in accordance with their terms (except
as such validity or enforceability may be limited by applicable bankruptcy,
insolvency, reorganization,

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The Union Light, Heat and Power Company
September 17, 2004
Page 2

moratorium or other similar laws affecting creditors' rights generally and by
general principles of equity, regardless of whether enforceability is considered
in a proceeding in equity or at law).

We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to us under the caption "Legal
Matters" in the prospectus forming a part of the Registration Statement.

Sincerely,

/s/ Thompson Hine LLP

THOMPSON HINE LLP