Interstate Power and Light Company to Expand Wind Generation Potential in Iowa

Whispering Willow Wind Farm in north central Iowa has potential to power more than 125,000 homes

CEDAR RAPIDS, Iowa, Feb. 6 /PRNewswire-FirstCall/ — Interstate Power and Light Company (IPL), a subsidiary of Alliant Energy Corporation (NYSE:LNT) announced today that the company has acquired a 300 megawatt wind power farm located in north central Iowa, near Hampton, Iowa from Iowa Winds, LLC. The wind farm is adjacent to a 200 megawatt wind power farm IPL acquired from Wind Capital Group, LLC in November 2007.


The ‘Whispering Willow Wind Farm’, which consists of the two recent site acquisitions, has the potential to produce up to 500 megawatts of emissions-free energy if completely developed. IPL currently anticipates developing 200 megawatts of wind power on the site beginning in 2009. IPL expects the first 200 megawatts to be commercially operable in 2010. IPL will still have the ability to develop up to an additional 300 megawatts of potential wind power on the site. A decision regarding the development of the wind farm’s additional 300 megawatts has not yet been made.

“We are preparing for our customers’ and Iowa’s energy future,” says Kim Zuhlke, vice president of new energy resources for Alliant Energy. “The Whispering Willow Wind Farm aligns squarely with Governor Culver’s vision that 25 percent of all the energy produced in Iowa comes from renewable sources by 2025. While the Whispering Willow Wind Farm is a great start, we are committed to maximizing Iowa’s wind energy potential. We will continue to seek environmentally friendly alternative sources of energy to complement our baseload generation initiatives.”

“Our company is proud of this announcement as we are committed to maximizing Iowa’s wind energy potential,” states Tom Aller, president of IPL. “The Whispering Willow Wind Farm clearly strengthens Iowa’s position as a leader in renewable energy. Iowans are working together to address our state’s future energy needs while fostering economic opportunities that create jobs and grow our renewable economy.”

“We appreciate the support that local government officials and the landowners have shown to our company in making the Whispering Willow Wind Farm a reality,” adds Mr. Aller. “We look forward to working with the landowners and government officials in north central Iowa to fully develop this wind generation opportunity.”

Currently, approximately four percent of IPL’s electric energy is derived from wind power. Upon completion of Whispering Willow Wind Farm’s initial 200 megawatts, IPL expects that approximately 6 percent of its electricity will be produced from renewable energy sources through either purchased power agreements or company-owned generation.

In addition to expanding its renewable energy portfolio, the company is also pursuing needed baseload generation and has proposed the addition of the Sutherland Generating Station Unit 4 in Marshalltown, Iowa. The 630 megawatt facility, of which IPL intends on owning 350 megawatts, is scheduled to be operational in 2013 and would provide enough energy to power approximately 472,500 homes and businesses.

The facility is being designed with hybrid technology, which would allow it to utilize switch grass, corn stalks or other similar agriculturally based products as fuel. This is expected to reduce the amount of coal burned at the facility. An additional 19 megawatt equivalent of steam cogeneration will be available for use by nearby industries. The addition of Sutherland Generating Station Unit 4 and up to 200 megawatts of wind generation is expected to lower IPL’s system-wide emissions levels, including sulfur dioxide (SO2), nitrogen oxide (NOx) and carbon dioxide (CO2), in 2013.

About Alliant Energy

Alliant Energy is an energy-services provider with subsidiaries serving approximately 1 million electric and more than 400,000 natural gas customers. Providing its customers in the Midwest with regulated electric and natural gas service is the company’s primary focus. Interstate Power and Light, the company’s Iowa utility subsidiary, serves 526,000 electric and 232,000 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

This press release includes forward-looking statements. These forward-looking statements can be identified as such because the statements include words such as “expects,” “anticipates,” “designed,” or other words of similar import. Similarly, statements that describe future plans or strategies are also 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 such factors as: state or federal regulatory actions or local government actions, including inability to obtain all necessary approvals and permits; unanticipated construction issues, delays or expenditures; failure of equipment and technology to perform as expected; current or future litigation, regulatory investigations, proceedings or inquiries that could impede the implementation of the IPL’s plans; political conditions in IPL’s service territories; and economic conditions in IPL’s service territory. 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 and IPL undertake no obligation to update publicly such statements to reflect subsequent events or circumstances