Exhibit 99.1

[SEMCO ENERGY LOGO]                                                       NEWS
1411 Third Street, Suit A                                                RELEASE
 Port Huron, MI 48060

FOR IMMEDIATE RELEASE

ANALYSTS CONTACT: THOMAS CONNELLY
Director Treasury and Investor Relations
Phone: 248-458-6163

MEDIA CONTACT: TIMOTHY LUBBERS
Director of Marketing and Corporate Communications
Phone: 810-887-4208

          SEMCO ENERGY ANNOUNCES CLOSINGS OF REPURCHASE AGREEMENT FOR
          CONVERTIBLE PREFERENCE STOCK AND OFFERING OF NEW CONVERTIBLE
                                PREFERRED STOCK

      PORT HURON, MI, MARCH 15, 2005 - SEMCO ENERGY, INC. (NYSE: SEN) announced
today that it has closed an offering of 325,000 shares of its 5% Series B
Convertible Cumulative Preferred Stock, generating gross proceeds to the Company
of $65 million, to qualified institutional buyers pursuant to Rule 144A under
the Securities Act of 1933 (the "Act") and to persons in offshore transactions
in reliance on Regulation S under the Act. SEMCO also has granted the initial
purchasers a 30-day option to purchase up to an additional 25,000 shares of
preferred stock in connection with the offering.

      Concurrently with the closing of the offering, on March 15, 2005, SEMCO
also closed the repurchase from an affiliate of k1 Ventures Ltd. of all of the
outstanding and issued shares (52,542.94) of SEMCO's 6% Series B Convertible
Preference Stock and warrants to purchase 905,565 shares of SEMCO's common
stock. The aggregate purchase price under the repurchase agreement was $60
million. SEMCO used $60 million of the proceeds from the preferred stock
offering to complete the repurchase.

      Additionally, the members of SEMCO's Board of Directors appointed by the
affiliate of k1, Jeffrey A. Safchik and Sherry A. Stanley, have resigned from
the Board.

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      "We want to thank Jeff and Sherry for their dedication and contributions
to SEMCO ENERGY," said George A. Schreiber, Jr., SEMCO ENERGY, Inc. President
and Chief Executive Officer. "Their perspective and insight will be missed and
we wish them well in all their future endeavors."

      Additional proceeds from the offering beyond those used in connection with
the repurchase of the preference stock will be used to repurchase, redeem, repay
or retire junior capital and other existing subordinated indebtedness or for
general corporate purposes.

      This announcement is neither an offer to sell nor a solicitation of an
offer to buy any of these securities. These securities have not been registered
under the Act or any state securities laws, and unless so registered, may not be
offered or sold in the United States except pursuant to an exemption from the
registration requirements of the Act and applicable state laws.

      SEMCO ENERGY, Inc. distributes natural gas to approximately 398,000
customers combined in Michigan, as SEMCO ENERGY GAS COMPANY, and in Alaska, as
ENSTAR Natural Gas Company. It also owns and operates businesses involved in
propane distribution, intrastate pipelines and natural gas storage in various
regions of the United States.

      The following is a "Safe-Harbor" statement under the Private Securities
Litigation Reform Act of 1995. This release contains forward-looking statements
that involve risks and uncertainties. Statements that are not historic facts,
including statements about the Company's outlook, beliefs, plans, goals and
expectations, are forward-looking statements. Factors that may impact
forward-looking statements include, but are not limited to, the effects of
weather, the economic climate, competition, commodity prices, changing
conditions in the capital markets, regulatory approval processes, success in
obtaining new business, success in defending claims against the Company, and
other risks detailed from time to time in the Company's Securities and Exchange
Commission filings.

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