Alliant Energy: Wisconsin Power and Light Company Receives Order Authorizing Interim Wholesale Electric Rate Increase

MADISON, Wis., – Wisconsin Power and Light Company (WP&L), a subsidiary of Alliant Energy Corporation has received an order from the Federal Energy Regulatory Commission (FERC) authorizing a $9.2 million (5.9 percent) interim increase in the company’s wholesale electric rates, effective June 1, 2007, subject to refund. FERC’s order came in response to requests filed by WP&L on Sept. 22 to implement a formula rate structure for its wholesale electric customers.

Final rates will be determined following a hearing and settlement judge procedure as outlined in FERC’s order.

Alliant Energy is an energy-services provider with subsidiaries serving approximately 1 million electric and over 400,000 natural gas customers. Providing its customers in the Midwest with regulated electric and natural gas service is the company’s primary focus. Wisconsin Power and Light, the company’s Wisconsin utility subsidiary, serves 453,000 electric and 179,000 natural gas customers. Alliant Energy, headquartered in Madison, Wis., 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 http://www.alliantenergy.com/ .