Wisconsin Power and Light Company: Outlines energy resources strategy

Media Contact: Steve Schultz (608) 458-3285

Investor Relations Contact: Susan Gille (608) 458-3956

The strategy will allow company to continue meeting customer needs in a cost-effective, safe and reliable manner into the future

MADISON, WI – July 27, 2012 – Wisconsin Power and Light Company (WPL), a subsidiary of Alliant Energy Corporation (NYSE:LNT), today outlined the next steps of its energy resources plan that transitions the company’s generating fleet to meet customers’ energy needs now and into the future.

“The plan calls for investing more than $1.4 billion in WPL’s generating fleet over the next five years. It provides a cleaner generation fleet that provides flexibility to ensure WPL can manage current and emerging environmental regulations. It also allows us to better manage cost impacts to customers while meeting their energy needs in a safe and reliable manner,” explains John Larsen, President – WPL. “We’re able to do this through a combination of investments in our generating fleet as well as some unit retirements.”

Investing in our future

WPL’s plan includes investing in environmental controls on its newer, larger and most efficient generating units to comply with existing and currently proposed state and federal environmental rules. These emission control plans allow WPL to continue meeting customers’ needs in an environmentally responsible manner now and into the future.

Generation investments include:

* Purchasing of the Riverside Energy Center, a 600 MW combined-cycle natural gas facility in Beloit, Wisconsin, by the end of 2012.

* Filing for additional emission controls for Edgewater Unit 5.

* Constructing emissions controls at Columbia Units 1 and 2 and Edgewater Unit 5.

“As we look to the future, we will continue to examine our current generating fleet as well as explore new generating options and sources in order to remain flexible for complying with emerging regulations in the most cost-effective ways to meet our customers’ energy needs,” adds Larsen.

Additional emission controls at Edgewater Unit 5

WPL today filed a construction application with the Public Service Commission of Wisconsin (PSCW) for authority to install a scrubber/baghouse system to reduce SO2 emissions from Edgewater Unit 5 to support compliance with the currently stayed Cross State Air Pollution Rule (CSAPR) or its replacement. Upon its completion, SO2 emissions from Unit 5 are expected to be reduced by approximately 90% per year from current levels. WPL expects a decision from the PSCW by the second quarter of 2013. If approved, construction on the approximately $390 million to $430 million project is expected to begin in 2014 and be completed in 2016. This project is expected to create as many as 400 jobs during peak construction.

Work currently underway

* WPL is constructing a nitrogen oxide (NOx) reduction system on Edgewater Unit 5 (Selective Catalytic Reduction or SCR System). The approximately $153 million SCR system will be completed by the end of 2012. Upon its successful completion, NOx emissions from Unit 5 are expected to be reduced by approximately 75% per year from current levels to comply with Wisconsin’s Reasonably Available Control Technology (RACT) Phase II requirements and CSAPR or its replacement.

WPL is constructing sulfur dioxide (SO2) and mercury reduction systems at Columbia Units 1 and 2 (scrubbers and baghouse/carbon injection systems). WPL’s share of the project cost is approximately $300 million. Scrubber and baghouse/carbon injection systems will be completed in 2014. Upon their successful completion, SO2 and mercury emissions from Columbia are expected to be reduced approximately 90% per year from levels prior to the installation of any SO2 and mercury emissions controls. The emission reductions support compliance with the CSAPR or its replacement and both state and Federal mercury rules.

Unit retirements

WPL has three generating units that have been in service for more than 50 years. Over this time, they have provided WPL customers with safe, reliable and cost effective electricity. However, as part of the transition of its generating fleet, WPL is planning an orderly retirement of its three oldest and smallest coal generating units by the end of 2015:

* Nelson Dewey Generating Station Units 1 & 2, located in Cassville, WI, which total approximately 200 MW.

* Edgewater Generating Station Unit 3, located in Sheboygan, WI, which is approximately 60 MW.

Fuel switching

WPL will also decide between repowering to natural gas or retiring Edgewater Generating Station Unit 4 by the end of 2018. This unit is located in Sheboygan, WI. It is approximately 330 MW, and co-owned with Wisconsin Public Service Corporation (WPS).

WPL will work with the Midwest Independent Transmission System Operator (MISO) to determine the final timing of these retirements and possible fuel switch.

“The investments necessary for long-term safe, reliable operation of these impacted units just wouldn’t be cost-beneficial for our customers,” explains Larsen. “Therefore, WPL has made the decision to transition or retire these units as economics or environmental rules dictate.”

Continued commitment to renewable resources and energy efficiency

Renewable energy also remains an important element of WPL’s generation portfolio, which includes both company-owned renewable generation as well as renewable energy purchased power agreements. WPL is also committed to energy efficiency and continues to support energy conservation efforts.

Wisconsin Power and Light Company (WPL), based in Madison, Wis., provides electric service to approximately 459,000 customers and natural gas service to approximately 180,000 customers in more than 600 communities across central and southern Wisconsin. WPL is committed to providing the energy and exceptional service its customers and communities expect – safely, reliably, and affordably. WPL is a subsidiary of Alliant Energy Corporation, for more information, visit alliantenergy.com or call 1-800-ALLIANT (800-255-4268).

This press release contains forward-looking statements. These forward-looking statements can be identified as such because the statements include words such as ”plan,” “scheduled,” “expect,” “approximately,” “future,” “will be,” 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; current or future litigation, regulatory investigations, proceedings or inquiries that could impede the implementation of the WPL’s plans; failure of equipment and technology to perform as expected; changes to environmental regulations; changes to WPL’s access to capital markets; political conditions in WPL’s service territories; and economic conditions in WPL’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 WPL undertake no obligation to update publicly such statements to reflect subsequent events or circumstances.