Severe Midwest Weather Impacts Alliant Energy Operations

		Alliant Energy is the parent company of two public utility companies--Interstate Power and Light Company (IPL) and Wisconsin Power and Light Company (WPL)--and of Alliant Energy Resources, Inc. (AER), the parent company of Alliant Energy's non-regulated operations. (PRNewsFoto/ALLIANT ENERGY CORPORATION) MADISON, WI UNITED STATES

Storm restoration process already underway in much of company's service territory MADISON, Wis., June 17 /PRNewswire-FirstCall/ -- Alliant Energy Corporation (NYSE: LNT) has begun the process of rebuilding, even as the effects of the extreme flooding, tornados and storms in Iowa and Wisconsin continue to be felt. Interstate Power and Light Company (IPL) and Wisconsin Power and Light Company (WPL), Alliant Energy's two utility subsidiaries, as well as Alliant Energy Resources, Inc. (AER) transportation investments are being affected. While the effects of the storms are being felt in scattered areas throughout the company's service territory, the downtown Cedar Rapids area appears to be the hardest hit. (Logo: http://www.newscom.com/cgi-bin/prnh/20020405/LNTLOGO) "The recent severe weather in our service territory has had a significant impact on our customers, employees and the communities that we serve," said Bill Harvey, Alliant Energy Chairman, President, and CEO. "Now that the flood waters are receding we are beginning the process of rebuilding." Below is an update on some of the service disruptions being experienced at Alliant Energy's operations in Iowa, the area most impacted by the flooding: -- Generation: IPL baseload units at Prairie Creek and Sixth Street Generating Stations in Cedar Rapids, Iowa and the Sutherland Generating Station in Marshalltown, Iowa remain offline due to flooding. These units represent approximately 380 megawatts, or less than 15 percent, of IPL's generating capability. Two of the generating stations are also unable to provide steam service to customers. The extent of the damage is currently being evaluated. -- Sales: Approximately 280 megawatts of load at IPL is unable to take electric service due to the impact of flooding. While the timing of return to operations for these customers is uncertain, we expect this load to eventually all come back on line. All customers in our utility service territory that are capable of receiving service are currently being served. -- Coal Supply: While both rail and barge deliveries continue to experience service disruptions, sufficient inventory exists at all locations to maintain normal levels of operation at units not impacted by the flooding. -- Distribution: Approximately fourteen substations in the Cedar Rapids area have experienced flooding, a modest amount given the approximately 150 substations operated by IPL in that area. Seven have already been placed back into service, while portable substations and other back up arrangements continue to be made. -- Office Buildings: The Alliant Energy Tower in Cedar Rapids, which houses over 1,000 Alliant Energy employees, had over seven feet of water on the first floor at the height of the flooding. With the exception of emergency service support facilities, the building is expected to have limited occupancy for the next few weeks. The Cedar Rapids electrical distribution operations center was also flooded and is currently out of service. However, the company has implemented its crisis management plan and is successfully operating from multiple other locations. -- AER Transportation: Both barge and short haul railroad service has been adversely impacted as a result of the floods. Alliant Energy's CRANDIC railroad was able to resume switching operations in Cedar Rapids earlier today. We are continuing to assess the magnitude of the damage and service disruption to customers. The railroad, along with its customers, is also adversely impacted due to damage that occurred to the overall transportation network. Alliant Energy has several mechanisms to mitigate the financial impact of these events. First, Alliant Energy has an insurance policy with total limits of $100 million for covered flood losses. This policy covers items including generating assets, substations, office and operating buildings, and related property. Second, both IPL and WPL will be evaluating regulatory options for cost recovery, as appropriate to each specific jurisdiction. Finally, the incremental costs of any required replacement power needs are expected to flow through IPL's energy adjustment clauses. Alliant Energy is currently unable to estimate the potential impact of these weather related events on 2008 earnings. An update to earnings guidance will be made when the evaluation of the damages and lost sales is substantially complete and reasonable estimates can be provided or as part of our next quarterly earnings release. The company does not expect any material long term earnings impact due to these events. "The work of our employees has been exemplary during this natural disaster," said Harvey. "Those efforts were aided by many who selflessly gave of their time. From local emergency management and law enforcement officials, to the many citizens who helped sand bag, to the National Guard, we are fortunate to have so many who have worked tirelessly over the past week." 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. 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. This press release includes forward-looking statements. These forward- looking statements can be identified as such because the statements include words such as "expected" or other words of similar import. Similarly, statements that describe future financial performance are forward-looking statements. Such statements are subject to certain risks and uncertainties that could cause actual results to differ materially from those currently anticipated. Actual results could be affected by the following factors, among others: federal and state regulatory or governmental actions, including the ability of IPL and WPL to recover costs associated with the flood damage; unanticipated impacts that storms or natural disasters in the service territories may have on operations; issues related to the availability of the generating facilities and the supply and delivery of fuel and purchased electricity and price thereof, including the ability to recover and retain purchased power, fuel and fuel-related costs through rates in a timely manner; issues associated with environmental remediation efforts and with environmental compliance generally; unplanned outages at generating facilities and risks related to recovery of incremental costs through rates; current or future litigation, regulatory investigations, proceedings or inquiries; economic and political conditions in the service territories; and continued access to the capital markets under competitive terms and rates. These factors should be considered when evaluating the forward-looking statements and undue reliance should not be placed on such statements. The forward- looking statements included herein are made as of the date hereof and Alliant Energy undertakes no obligation to update publicly such statements to reflect subsequent events or circumstances. ANR279-08