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                                                                     EXHIBIT 3.1


                AMENDED AND RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                                  AQUILA, INC.


     FIRST: The name of the corporation is Aquila, Inc. (the "Corporation").

     SECOND: The registered office of the Corporation is to be located at 1209
Orange Street, Wilmington, County of New Castle, Delaware, 19801. The name of
the Corporation's registered agent at such address is The Corporation Trust
Company.

     THIRD: The purpose of the Corporation is to engage in any lawful act or
activity for which corporations may be organized under the General Corporation
Law of the State of Delaware.

     FOURTH: The total number of shares of stock which the Corporation is
authorized to issue is One Thousand (1,000) shares of Common Stock of the par
value of $1.00 per share.

     FIFTH: The name and mailing address of the person currently serving as the
director of the Corporation, and who will continue to serve the director until
the next annual meeting of the stockholders or until their successors are duly
elected and qualified:

              NAME                                   ADDRESS
              ----                                   -------
         Robert K. Green                        20 W. 9th Street
                                                Kansas City, MO 64105

     SEVENTH: The Board of Directors of the Corporation is expressly authorized
to make, alter, amend, or repeal the By-Laws of the Corporation. Election of
Directors need not be by written ballot unless the By-Laws of the Corporation
shall so provide.

     EIGHTH: The Corporation shall, to the fullest extent permitted by the
General Corporation Law of Delaware, as amended from time to time, indemnify all
persons whom it may indemnify pursuant thereto.

     NINTH: The Corporation reserves the right to amend, alter, change or repeal
any provision contained in this Certificate of Incorporation in the manner now
or hereafter prescribed by law, and all rights and powers conferred herein on
stockholders, directors and officers are subject to this reserved power.

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                              AMENDED AND RESTATED
                            CERTIFICATE OF AMENDMENT
                                       OF
                                  AQUILA, INC.


     Aquila, Inc., a corporation organized and existing under and by virtue of
the General Corporation Law of the State of Delaware,

     DOES HEREBY CERTIFY:

     FIRST: That the Board of Directors of said corporation, by the unanimous
written consent of its members, filed with the minutes of the Board, adopted a
resolution proposing and declaring advisable the following amendment to the
Certificate of Incorporation of said corporation:

     RESOLVED, that the Amended and Restated Certificate of Incorporation of
Aquila, Inc. be amended by changing the First Article thereof so that, as
amended, said Article shall be and read as follows:

               FIRST: The name of the corporation is Aquila Merchant Group, Inc.
          (the "Corporation").

     SECOND: That in lieu of a meeting and vote the Sole Stockholder, the Sole
Stockholder has given unanimous written consent to said amendment in accordance
with the provisions of Section 228 of the General Corporation Law of the State
of Delaware.

     THIRD: That the aforesaid amendment was duly adopted in accordance with the
applicable provisions of Sections 242 and 228 of the General Corporation Law of
the State of Delaware.

     IN WITNESS WHEREOF, Edward K. Mills, President of Aquila, Inc. has caused
this certificate to be signed this 1st day of March, 2002.

                                       AQUILA, INC.

                                        By:       EDWARD K. MILLS
                                            -----------------------------
                                            Edward K. Mills, President