FILER:

COMPANY DATA:
COMPANY CONFORMED NAME:                ALLIANT ENERGY CORPORATION
CENTRAL INDEX KEY:                             
STANDARD INDUSTRIAL CLASSIFICATION:    ELECTRIC AND OTHER SERVICES COMB. [4931]
IRS NUMBER:                            391380265
STATE OF INCORPORATION:                WI
FISCAL YEAR END:                       12/31

FILING VALUES:
FORM TYPE:                             35-CERT
SEC ACT:
SEC FILE NUMBER:                       070-10052
FILM NUMBER:                           

BUSINESS ADDRESS:
STREET 1:                              4902 N Biltmore Lane
CITY:                                  MADISON
STATE:                                 WI
ZIP:                                   53718
BUSINESS PHONE:                        608-458-3311

MAILING ADDRESS
STREET 1:                              P. O. BOX  77007
CITY:                                  MADISON
STATE:                                 WI
ZIP:                                   53707





                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington D. C. 20549

PUBLIC UTILITY HOLDING COMPANY ACT OF 1935
File No. 70-10052

REPORT PERIOD
October 1, 2004 through December 31, 2004

In the Matter of

ALLIANT ENERGY CORPORATION, ET AL

     ALLIANT ENERGY  CORPORATION  ("AEC") hereby certifies on behalf of itself ,
Wisconsin Power and Light Company  ("WPL"),  Interstate  Power and Light Company
("IPL"),  and Alliant Energy Corporate  Services,  Inc.( "Services") that during
the period  from  October 1, 2004  through  December  31,  2004 (the  "Reporting
Period"):


1(a). Alliant Energy Corporation issued commercial paper as follows:


                                                       

                  October         November         December        Quarter   
               --------------------------------------------------------------
Begin Balance     $      0        $      0         $      0        $      0
CP Issued         $      0        $      0         $      0        $      0
CP Matured        $      0        $      0         $      0        $      0
Ending Balance    $      0        $      0         $      0        $      0



1(b).Weighted  Average for the interest rate for the period for short-term  debt
     was as follows:

       October         -
       November        -
       December        -
       Quarter         -


        
1(c). Alliant Energy Corporation borrowed from Banks as follows:

     N/A


1(d).The weighted  average  interest rate for the period for the bank borrowings
     was as follows:

     N/A




2(a). Interstate Power and Light Company issued commercial paper as follows:


                                                       

                  October         November         December        Quarter          
                --------------------------------------------------------------------
Begin Balance    $  21,000,000    $  25,000,000    $  27,000,000    $   21,000,000
CP Issued        $ 684,500,000    $ 502,500,000    $ 342,000,000    $1,529,000,000
CP Matured       $ 680,500,000    $ 500,500,000    $ 333,000,000    $1,514,000,000
Ending Balance   $  25,000,000    $  27,000,000    $  36,000,000    $   36,000,000



2(b).Weighted  Average for the interest rate for the period for short-term  debt
     was as follows:

        October        1.867%
        November       2.036%
        December       2.240%
        Quarter        2.007%

          
3(a).For each of the  companies  participating  in the Utility Money Pool during
     the Reporting Period, the maximum principal amount of short-term borrowings
     outstanding  from the Utility  Money Pool,  sources  other than the Utility
     Money Pool, and the maximum total short-term borrowings  outstanding during
     the Reporting Period,  and the Securities and Exchange  Commission  ("SEC")
     borrowing limit for each  participant as of the end of the Reporting Period
     were as follows:


                                                        
                                Maximum
                 Maximum        Other            Maximum
                 Money Pool     Short-Term        Total             SEC
Company          Borrowings     Borrowings       Borrowings         Limit

IPL (*)          $         0    $  53,000,000    $   53,000,000   $ 300,000,000
WP&L     (**)    $         0    $  47,000,000    $   47,000,000             NA
SERVICES (***)   $ 9,254,521    $           0    $    9,254,521             NA    

     (*)  IPL ceased borrowing from the Money Pool as of October 11, 2002.
 
     (**) All borrowings by WP&L from the Money Pool are exempt under Rule 52(a)
          and  are  shown  here  for  information   purposes  only.  WPL  ceased
          borrowings from the Money Pool as of July 25, 2002.

     (***)Borrowings  by Services are exempt under Rule 52(b) and are shown here
          for information purposes only.

              
4.   During  the  Reporting  Period,  the  weighted  average  interest  rate for
     borrowings through the Money Pool was 1.90%.


5.   The maximum amount of AEC's  short-term  borrowings on behalf of itself and
     the above named participants in the Utility Money Pool during the Reporting
     Period,  and its SEC limit as of the end of the Reporting  Period,  were as
     follows:


                                                       

                 Maximum        Maximum         Maximum
                 Loans to       Corporate       Short-Term        SEC
                 Money Pool     Borrowings      Borrowings        Limit

AEC             $ 9,254,521     $       0       $        0       $ 1,000,000,000
________________   


     Said  transactions  have been carried out in accordance  with the terms and
conditions   of,   and  for  the   purpose   represented   in,   the   Form  U-1
Application-Declaration,  as amended,  of AEC, et al, in File  70-10052,  and in
accordance with the terms and conditions of the SEC's order dated June 21, 2002,
permitting said Application-Declaration to become effective.


DATED:  February 8, 2005

                                 ALLIANT ENERGY CORPORATION             
                                 INTERSTATE POWER AND LIGHT COMPANY
                                 ALLIANT ENERGY CORPORATE SERVICES INC. 

                                 BY:  ALLIANT ENERGY CORPORATION

                      
                               BY:    /s/ Thomas L Hanson
                                   ------------------------------------------
                                 Thomas L. Hanson
                                 Vice President, Treasurer