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                                                                     EXHIBIT 5.2


                     [RICHARDS, LAYTON & FINGER LETTERHEAD]



                               November 30, 1999



SEMCO Capital Trust I
SEMCO Capital Trust II
SEMCO Capital Trust III
c/o SEMCO Energy, Inc.
405 Water Street
Port Huron, Michigan 48061-5026

         Re:   SEMCO Capital Trust I
               SEMCO Capital Trust II
               SEMCO Capital Trust III

Ladies and Gentlemen:

         We have acted as special Delaware counsel for SEMCO Energy, Inc., a
Michigan corporation (the "Company"), SEMCO Capital Trust I, a Delaware business
trust ("Trust I"), SEMCO Capital Trust II, a Delaware business trust ("Trust
II"), and SEMCO Capital Trust III ("Trust III"). Trust I, Trust II and Trust III
are hereinafter collectively referred to as the "Trusts" and sometimes
hereinafter individually referred to as a "Trust"), in connection with the
matters set forth herein. At your request, this opinion is being furnished to
you.

         For purposes of giving the opinions hereinafter set forth, our
examination of documents has been limited to the examination of originals or
copies of the following:

         (a)  The Certificate of Trust of Trust I, as filed with the Secretary
of State on November 23, 1999;

         (b)  The Certificate of Trust of Trust II, as filed with the Secretary
of State on November 23, 1999;

         (c)  The Certificate of Trust of Trust III, as filed with the Secretary
of State on November 23, 1999;
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SEMCO Capital Trust I
SEMCO Capital Trust II
SEMCO Capital Trust III
November 30, 1999
Page 2


          (d)  The Trust Agreement of Trust I, dated as of November 23, 1999
among the Company and the trustees of Trust I named therein;

          (e)  The Trust Agreement of Trust II, dated as of November 23, 1999
among the Company and the trustees of Trust II named therein;

          (f)  The Trust Agreement of Trust III, dated as of November 23, 1999
among the Company and trustees of Trust III named therein;

          (g)  The Registration Statement (the "Registration Statement") on
Form S-3, including a preliminary prospectus with respect to the Trusts (the
"Prospectus"), relating to the Preferred Securities of the Trusts representing
undivided beneficial interests in the assets of the Trusts (each, a "Preferred
Security" and collectively, the "Preferred Securities"), as filed by the
Company and the Trusts with the Securities and Exchange Commission on or about
November 30, 1999;

          (h)  A form of Amended and Restated Trust Agreement for each of the
Trusts, to be entered into between the Company, the trustees of the Trust named
therein, and the holders, from time to time, of the undivided beneficial
interests in the assets of such Trust (including Exhibits C and D thereto)
(collectively, the "Trust Agreements" and individually, a "Trust Agreement"),
attached as an exhibit to the Registration Statement; and

          (i)  A Certificate of Good Standing for each of the Trusts, dated
November 24, 1999, obtained from the Secretary of State.

          Initially capitalized terms used herein and not otherwise defined are
used as defined in the Trust Agreements.

          For purposes of this opinion, we have not reviewed any documents
other than the documents listed in paragraphs (a) through (i) above. In
particular, we have not reviewed any document (other than the documents listed
in paragraphs (a) through (i) above) that is referred to in or incorporated by
reference into the documents reviewed by us. We have assumed that there exists
no provision in any document that we have not reviewed that is inconsistent
with the opinions stated herein. We have conducted no independent factual
investigation of our own but rather have relied solely upon the foregoing
documents, the statements and information set forth therein and the additional
matters recited or assumed herein, all of which we have assumed to be true,
complete and accurate in all material respects.

          With respect to all documents examined by us, we have assumed (i) the
authenticity of all documents submitted to us as authentic originals, (ii) the
conformity with


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SEMCO Capital Trust I
SEMCO Capital Trust II
SEMCO Capital Trust III
November 30, 1999
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the originals of all documents submitted to us as copies or forms, and (iii) the
genuineness of all signatures.

          For purposes of this opinion, we have assumed (i) that each of the
Trust Agreements will constitute the entire agreement among the parties thereto
with respect to the subject matter thereof, including with respect to the
creation, operation and termination of the applicable Trust, and that the Trust
Agreements and the Certificates of Trust will be in full force and effect and
will not be amended, (ii) except to the extent provided in paragraph 1 below,
the due organization or due formation, as the case may be, and valid existence
in good standing of each party to the documents examined by us under the laws of
the jurisdiction governing its organization or formation, (iii) the legal
capacity of natural persons who are parties to the documents examined by us,
(iv) that each of the parties to the documents examined by us has the power and
authority to execute and deliver, and to perform its obligations under, such
documents, (v) the due authorization, execution and delivery by all parties
thereto of all documents examined by us, (vi) the receipt by each Person to whom
a Preferred Security is to be issued by the Trusts (collectively, the "Preferred
Security Holders") of a Preferred Security Certificate for such Preferred
Security and the payment for such Preferred Security, in accordance with the
Trust Agreements and the Registration Statement, and (vii) that the Preferred
Securities are authenticated, issued and sold to the Preferred Security Holders
in accordance with the Trust Agreements and the Registration Statement. We have
not participated in the preparation of the Registration Statement or the
Prospectus and assume no responsibility for their contents.

         This opinion is limited to the laws of the State of Delaware (excluding
the securities laws of the State of Delaware), and we have not considered and
express no opinion on the laws of any other jurisdiction, including federal laws
and rules and regulations relating thereto. Our opinions are rendered only with
respect to Delaware laws and rules, regulations and orders thereunder which are
currently in effect.

         Based upon the foregoing, and upon our examination of such questions of
law and statutes of the State of Delaware as we have considered necessary or
appropriate, and subject to the assumptions, qualifications, limitations and
exceptions set forth herein, we are of the opinion that:

         1. Each of the Trusts has been duly created and is validly existing in
good standing as a business trust under the Business Trust Act.

         2. The Preferred Securities of each Trust will represent valid and,
subject to the qualifications set forth in paragraph 3 below, fully paid and
nonassessable undivided beneficial interests in the assets of the applicable
Trust.

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SEMCO Capital Trust I
SEMCO Capital Trust II
SEMCO Capital Trust III
November 30, 1999
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         3. The Preferred Security Holders, as beneficial owners of the
applicable Trust, will be entitled to the same limitation of personal liability
extended to stockholders of private corporations for profit organized under the
General Corporation Law of the State of Delaware. We note that the Preferred
Security Holders may be obligated to make payments as set forth in the Trust
Agreement.

         We consent to the filing of this opinion with the Securities and
Exchange Commission as an exhibit to the Registration Statement. In addition, we
hereby consent to the use of our name under the heading "Legal Matters" in the
Prospectus and "Legal Opinions" in the Prospectus Supplement. In giving the
foregoing consents, we do not thereby admit that we come within the category of
persons whose consent is required under Section 7 of the Securities Act of 1933,
as amended, or the rules and regulations of the Securities and Exchange
Commission thereunder. Except as stated above, without our prior written
consent, this opinion may not be furnished or quoted to, or relied upon by, any
other person for any purpose.

                                           Very truly yours,


                                           /s/ Richards, Layton & Finger, P.A.


WF/mc