ALLIANT ENERGY
Alliant Energy announces new Upland Prairie Wind Farm
Company's wind expansions would power up to 430,000 Iowa homes

Alliant Energy's Iowa energy company continues moving toward a cleaner energy future with the start of major construction on its next wind farm in spring 2018. The company finalized an agreement with Apex Clean Energy for Upland Prairie Wind Farm. The 300-megawatt project is located in Clay and Dickinson counties in northwest Iowa.

"We are bringing more clean and cost-competitive wind energy to our customers," said Doug Kopp, president of Alliant Energy's Iowa energy company. "If our second wind expansion project is approved, one third of our energy in Iowa will be from wind, starting in 2020."

This project will add construction and other jobs, as well as tens of millions of dollars in additional property taxes to the local communities and lease payments to landowners.

"Apex wind projects are designed to meet the needs of forward-thinking utilities such as Alliant Energy," said Mark Goodwin, president and CEO of Apex. "We share the same priorities, especially strong community partnerships."

Alliant Energy received approval in 2016 to add up to 500 megawatts of wind energy. The company has requested a similar expansion from the Iowa Utilities Board again in 2017. The combined projects would represent a $1.8 billion investment and add up to 1,000 megawatts of new wind generation in Iowa. Together, that's enough to power up to 430,000 Iowa homes a year.

Upland Prairie Wind Farm facts:

• Number of turbines: 121
• Size of project: 300 megawatts
• Annual energy output: enough for about 130,000 homes a year
• Local tax benefits: more than $40 million over the life of the project
• Landowner payments: approximately $45 million for the next 25 years

Alliant Energy Corporation's Iowa utility subsidiary, Interstate Power and Light Company (IPL), utilizes the trade name of Alliant Energy (NYSE:LNT). The Iowa utility is based in Cedar Rapids, Iowa, and provides electric service to 490,000 retail customers and natural gas service to 220,000 retail customers. The employees of Alliant Energy focus on delivering the energy solutions and exceptional service their customers and communities expect - safely, efficiently and responsibly. Alliant Energy Corporation is a component of the S&P 500. For more information, visit alliantenergy.com.

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