ALLIANT ENERGY RESOURCES, INC.

                                Offer to Exchange
                     Registered 7 3/8% Senior Notes due 2009
      For Any and All Outstanding Unregistered 7 3/8% Senior Notes due 2009

                                                              ____________, 1999

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           THE EXCHANGE OFFER WILL EXPIRE AT 5:00 P.M., NEW YORK CITY
            TIME, ON ___________, 2000, UNLESS THE OFFER IS EXTENDED.
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To  Brokers, Dealers, Commercial Banks,
    Trust Companies and Other Nominees:

     Alliant  Energy  Resources,  Inc.  (the  "Company")  is offering,  upon and
subject  to  the  terms  and  conditions  set  forth  in the  Prospectus,  dated
____________,  1999 (the  "Prospectus"),  and the enclosed Letter of Transmittal
(the "Letter of  Transmittal"),  to exchange (the  "Exchange  Offer") its 7 3/8%
Senior Notes due 2009 (the "New Senior Notes") which have been registered  under
the Securities Act of 1933, as amended, for all of its outstanding  unregistered
7 3/8% Senior Notes due 2009 (the "Existing  Senior Notes").  The Exchange Offer
is being made in order to satisfy certain  obligations of the Company  contained
in the Registration  Rights Agreement dated November 9, 1999, by and between the
Company and the initial purchasers named therein,  relating to the 7 3/8% Senior
Notes due 2009.

     We are requesting  that you contact your clients for whom you hold Existing
Senior  Notes  regarding  the  Exchange  Offer.  For  your  information  and for
forwarding to your clients for whom you hold Existing Senior Notes registered in
your name or in the name of your  nominee,  or who hold  Existing  Senior  Notes
registered in their own names, we are enclosing the following documents:

     1.   The Prospectus;

     2. The Letter of Transmittal  for your use and for the  information of your
clients;

     3. A form of Notice of Guaranteed Delivery;

     4. A form of letter  which may be sent to your  clients for whose  accounts
you hold  Existing  Senior  Notes  registered  in your  name or the name of your
nominee, along with an instruction form for obtaining such clients' instructions
with respect to the Exchange Offer; and

     5.  Guidelines  for  Certification  of  Taxpayer  Identification  Number on
Substitute Form W-9.

     Your prompt  action is  required.  The  Exchange  Offer will expire at 5:00
p.m., New York City time, on ____________,  2000, unless extended by the Company
(the "Expiration Date"). Existing Senior Notes tendered pursuant to the Exchange
Offer may be withdrawn at any time before the Expiration Date.

     To  participate in the Exchange  Offer,  certificates  for Existing  Senior
Notes, or a timely confirmation of a book-entry transfer of such Existing Senior
Notes  into the  Exchange  Agent's  account


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at the  Depository  Trust  Company,  together  with a duly executed and properly
completed  Letter of  Transmittal  (or  facsimile  thereof),  with any  required
signature  guarantees  and any other required  documents,  should be sent to the
Exchange Agent,  all in accordance with the instructions set forth in the Letter
of Transmittal and the Prospectus.

     If the registered  holder of Existing  Senior Notes desires to tender,  but
such  Existing  Senior  Notes are not  immediately  available,  or time will not
permit such holder's Existing Senior Notes or other required  documents to reach
the Exchange Agent before the  Expiration  Date, or the procedure for book-entry
transfer  cannot be  completed  on a timely  basis,  a tender may be effected by
following the guaranteed delivery  procedures  described in the Prospectus under
"The Exchange Offer - Guaranteed Delivery Procedures."

     We will, upon request,  reimburse  brokers,  dealers,  commercial banks and
trust companies for reasonable and necessary costs and expenses incurred by them
in forwarding the Prospectus and the related  documents to the beneficial owners
of Existing Senior Notes held by them as nominee or in a fiduciary capacity.  We
will pay or cause to be paid all transfer  taxes  applicable  to the exchange of
Existing  Senior Notes  pursuant to the Exchange  Offer,  except as set forth in
Instruction 6 of the Letter of Transmittal.

     Any inquiries you may have with respect to the Exchange  Offer, or requests
for  additional  copies of the  enclosed  materials,  should be  directed to the
Exchange Agent at its address and telephone number set forth on the front of the
Letter of Transmittal.

                                       Very truly yours,



                                       FIRSTAR BANK, N.A.


     Nothing  herein or in the enclosed  documents  shall  constitute you or any
person as an agent of the Company or the Exchange Agent, or authorize you or any
other person to use any document or make any  statements  on behalf of either of
them with respect to the Exchange Offer, except for statements expressly made in
the Prospectus or the Letter of Transmittal.




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