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                                                                    Exhibit 10.5

                                LETTER OF INTENT

Date:     March 24, 2005

Parties:  Fagen, Inc., a Minnesota Corporation, of Granite Falls, MN ("Fagen")
          and Advanced BioEnergy, LLC, a Delaware limited liability company
          ("Owner")


WHEREAS, Owner is an entity organized to facilitate the development and
building of a 100 MGY gas-fired fuel ethanol plant near Fairmont, Nebraska (the
"Facility" or "Project");

WHEREAS, Fagen is an engineering and construction firm capable of providing
development assistance, as well as designing and constructing the Facility being
considered by Owner; and

WHEREAS, this Letter of Intent supercedes and replaces any prior Letter of
Intent between Fagen and Owner relating to the Project.

NOW, THEREFORE, in consideration of the promises and mutual covenants set forth
herein, Owner and Fagen agree to use best efforts in jointly developing this
Project under the following terms:

               1. Owner agrees that Fagen will design-build the Facility if
          determined by Owner to be feasible and if adequate, financing is
          obtained. Should Owner choose to develop or pursue a relationship with
          a company other than Fagen to provide the preliminary engineering or
          design-build services for the project, then Owner shall reimburse
          Fagen for all expenses Fagen has incurred in connection with the
          Project based upon Fagen's standard rate schedule plus all third party
          costs incurred from the date of this Letter of Intent. Such expenses
          include, but are not limited to, labor rates and reimbursable expenses
          such as legal charges for document review and preparation, travel
          expenses, reproduction costs, long distance phone cost, and postage.
          In the event Fagen's services are terminated by Owner, title to the
          technical data, which may include preliminary engineering drawings and
          layouts and proprietary process related information, shall remain with
          Fagen; however, Owner shall, upon payment of the foregoing expenses,
          have the limited license to use the above described technical data,
          excluding proprietary process related information, for construction,
          operation, repair and maintenance of the Project.

               If Fagen intentionally or by gross negligence fails or refuses to
          comply with its commitments contained in this Letter of Intent, Fagen
          shall absorb all of its own expenses, and Owner shall have the right
          to terminate the Letter of Intent immediately upon written notice to
          Fagen, and Owner shall be released from its obligations to pay or
          reimburse Fagen as described above.

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          2.   Fagen will provide Owner with assistance in evaluating, from both
     a technical and business perspective:

               -    Owner organizational options;
               -    The appropriate location of the proposed Facility; and
               -    Business plan development.

     Fagen assumes no risk or liability of representation or advice to Owner by
     assisting in evaluating the above. All decisions made regarding
     feasibility, financing, and business risks are the Owner's responsibility
     and liability.

          3.   Fagen agrees to design-build the Facility, utilizing ICM, Inc.
     technology in the plant process, for a lump sum price of $98,000,000.00.
     This lump sum price shall remain firm by Fagen to Owner until December 31,
     2005, and may be subject to revision by Fagen after such date.

          4.   Fagen will. assist Owner in locating appropriate management for
     the Facility.

          5.   Fagen will assist Owner in presenting information to potential
     investors, potential lenders, and various entities or agencies that may
     provide project development assistance.

          6.   During the term of this Letter of Intent the Owner agrees that
     Fagen will be the exclusive Developer and Design-Builder for the Owner in
     connection with matters covered by this Letter of Intent, and Owner shall
     not disclose any information related to this Letter of Intent to a
     competitor or prospective competitor of Fagen.

          7.   This Letter of Intent shall terminate on December 31, 2005 unless
     the basic size and design of the Facility have been determined and mutually
     agreed upon, and a specific site or sites have been determined and mutually
     agreed upon, and at least 10% of the necessary equity has been raised.
     Furthermore, this Letter of Intent shall terminate on December 31, 2006
     unless financing for the Facility has been secured. Either of the
     aforementioned dates may be extended upon mutual written agreement of the
     Parties.

          8.   Fagen and Owner agree to negotiate in good faith and enter into a
     definitive lump sum design-build agreement, including Exhibits thereto,
     acceptable to the Parties. Upon execution of such agreement, this Letter of
     Intent becomes null and void.

          9.   The Parties will jointly agree on the timing and content of any
     public disclosure, including, but not limited to, press releases, relating
     to Fagen's involvement in Owner's Project, and no such disclosure shall be
     made without mutual consent and approval, except as may be required by
     applicable law.

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          10.  The Parties agree that this Letter of Intent may be modified only
     by written agreement by the Parties.

          11.  This Letter of Intent may be executed in one or more
     counterparts, each of which when so executed and delivered shall be deemed
     an original, but all of which taken together constitute one and the same
     instrument. Signatures which have been affixed and transmitted by facsimile
     shall be binding to the same extent as an original signature, although the
     Parties contemplate that a fully executed counterpart with original
     signatures will be delivered to each Party.


ADVANCED BIOENERGY, LLC                       FAGEN, INC.

By:      /s/Revis L. Stephenson               By:      /s/O. Wayne Mitchell
    --------------------------------                ----------------------------

Its:     Chairman                             Its:     Sr. V.P.
      ------------------------------                ----------------------------

Date:          3/24/05                        Date:    3/28/05
       -----------------------------                ----------------------------

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