Interstate Power and Light Company declares preferred stock dividend

     Interstate Power and Light Company declares preferred stock dividend

PR Newswire

CEDAR RAPIDS, Iowa, May 9, 2013

CEDAR RAPIDS, Iowa, May 9, 2013 /PRNewswire/ -- The Board of Directors of
Interstate Power and Light Company (IPL) has declared dividends for its
preferred stock shareowners of record on May 31, 2013. The dividends, which
are payable on June 17, 2013, are as follows:

$0.304583 per share on the 5.1% Series D Cumulative Preferred Stock

(Logo: http://photos.prnewswire.com/prnh/20020405/LNTLOGO)

About Alliant Energy – IPL

Interstate Power and Light Company (IPL), based in Cedar Rapids, Iowa,
provides electric service to 525,000 customers and natural gas service to
233,000 customers in more than 700 communities throughout Iowa and southern
Minnesota. IPL is committed to providing the energy and exceptional service
its customers and communities expect – safely, reliably, and affordably. IPL
is a subsidiary of Alliant Energy Corporation (NYSE: LNT). For more
information, visit alliantenergy.com or call 1-800-ALLIANT (800-255-4268).

SOURCE Interstate Power and Light Company

Contact: Media, Scott Reigstad (608) 458-3145 or Investor Relations, Susan
Gille (608) 458-3956