ALLIANT ENERGY RESOURCES, INC.


                                Offer to Exchange
                     Registered 9.75% Senior Notes due 2013
      For Any and All Outstanding Unregistered 9.75% Senior Notes due 2013

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        The Exchange Offer will expire at 11:59 p.m., New York City time,
              on ____________, 2003, unless the Offer is extended.
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                                                             _____________, 2003

To Our Clients:

     Enclosed for your consideration is a Prospectus, dated ___________, 2003
(the "Prospectus"), and the related Letter of Transmittal (the "Letter of
Transmittal"), relating to the offer (the "Exchange Offer") of Alliant Energy
Resources, Inc. (the "Company") to exchange its 9.75% Senior Notes due 2013 (the
"New Senior Notes") which have been registered under the Securities Act of 1933,
as amended, for all of its outstanding unregistered 9.75% Senior Notes due 2013
(the "Old Senior Notes"), upon the terms and subject to the conditions described
in the Prospectus and the Letter of Transmittal. The Exchange Offer is being
made in order to satisfy certain obligations of the Company contained in the
Registration Rights Agreement, dated December 26, 2002, by and between the
Company and the initial purchasers named therein, related to the 9.75% Senior
Notes due 2013.

     This material is being forwarded to you as the beneficial owner of the Old
Senior Notes held by us for your account but not registered in your name. A
tender of such Old Senior Notes may only be made by us as the holder of record
and pursuant to your instructions.

     Accordingly, we request instructions as to whether you wish us to tender on
your behalf the Old Senior Notes held by us for your account, pursuant to the
terms and conditions set forth in the enclosed Prospectus and Letter of
Transmittal. We urge you to read the Prospectus carefully before instructing us
as to whether or not to tender your Old Senior Notes.

     Your instructions should be forwarded to us as promptly as possible in
order to permit us to tender the Old Senior Notes on your behalf in accordance
with the provisions of the Exchange Offer. The Exchange Offer will expire at
11:59 p.m., New York City time, on ___________, 2003, unless extended by the
Company. Any Old Senior Notes tendered pursuant to the Exchange Offer may be
withdrawn at any time before the Expiration Date.

     If you wish to have us tender your Old Senior Notes, please instruct us by
completing, executing and returning to us the instruction form enclosed with
this letter. The Letter of Transmittal is furnished to you for information only
and may not be used directly by you to tender Old Senior Notes.

     If we do not receive written instructions in accordance with the procedures
presented in the Prospectus and the Letter of Transmittal we will not tender any
of the outstanding Old Senior Notes on your account.