Alliant Energy: Sells Energy Management Business

Alliant Energy Media Contacts:
Scott Drzycimski (319) 786-7500

Karen Whitmer (608) 458-4839

Alliant Energy Investor Relations: Becky Johnson (608) 458-3267

WPS Energy Services Media Contact: Chris Matthiesen (920) 617-6005

MADISON, Wis. – December 2, 2004 – Alliant Energy Corp. (NYSE: LNT) announced that yesterday it successfully completed the sale of substantially all of the major contracts held by its energy management services business to WPS Energy Services, Inc., a subsidiary of WPS Resources Corp. (NYSE: WPS) of Green Bay, Wis. The energy management services business had offices in Wisconsin, Minnesota and Florida, and was part of Alliant Energy Resources, Inc.’s (AER) Integrated Services Co. (ISCO) business platform. AER is the parent company of Alliant Energy’s non-regulated businesses. The terms of the sale were not disclosed.

Citing continued efforts to narrow its strategic focus to primarily domestic utility operations, Alliant Energy announced in July its plans to divest certain ISCO businesses, including its energy management services business, its energy services business (Cogenex Corp.), and NG Energy Trading, which was sold on Sept. 1, 2004. “We are pleased with this sale,” said Bill Harvey, Alliant Energy president and chief operating officer. “It is yet another example of Alliant Energy’s efforts to continue to narrow its business scope and concentrate on those opportunities now available to us in our core domestic utility operations.”

WPS Energy Services looks forward to the opportunity to serve its new customers. “WPS Energy Services continues to grow its business in the energy management sector by providing customers the expertise needed to manage their business’ energy needs in volatile energy markets,” said Chris Matthiesen, director – Consulting at WPS Energy Services. “Our focus in the energy management sector is to reduce costs, manage risk, and create new competitive advantages for our customers through comprehensive expert energy management,” added Matthiesen.

Alliant Energy is an energy-services provider that serves more than three million customers worldwide. Providing its customers in the Midwest with regulated electricity and natural gas service remains the company’s primary focus. Other key business platforms include the international energy market and non-regulated domestic generation. Alliant Energy is a Fortune 1000 company traded on the New York Stock Exchange under the symbol LNT. For more information, visit the company’s Web site at www.alliantenergy.com

WPS Energy Services, Inc., is a diversified natural gas and electric marketer, which serves customers with physical natural gas and electric supplies in the northeast quadrant of the United States and adjacent portions of Canada. Its corporate mission is to “Provide Customers with the Best Value in Energy and Related Services”. Its Energy Management Service serves larger commercial and industrial customers, with multiple facilities, throughout North America. It is designed to help customers get their arms around utility data and reduce customer costs and risks. For more information visit: www.wpsenergy.com.