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News Release FOR IMMEDIATE RELEASE Alliant Energy Utilities and Corporate Services American Transmission Company ( ATC ) Holdings Non - utility and Parent Alliant Energy Consolidated Media Hotline : Investor Relations : ALLIANT ENERGY ANNOUNCES FIRST QUARTER 2021 RESULTS MADISON , Wis . - May 6 , 2021 - Alliant Energy Corporation ( NASDAQ : LNT ) today announced U.S. generally accepted accounting principles ( GAAP ) and non - GAAP consolidated unaudited earnings per share ( EPS ) for the three months ended March 31 as follows : GAAP EPS 2021 $ 0.66 0.03 ( 0.01 ) $ 0.68 2020 Higher revenue requirements primarily due to increasing rate base Timing of income tax expense Higher depreciation expense Lower allowance for funds used during construction Estimated temperature impact on retail electric and gas sales 608-458-4040 Susan Gille ( 608 ) 458-3956 1 $ 0.72 0.03 ( 0.05 ) $ 0.70 Alliant Energy Corporation Corporate Headquarters 4902 North Biltmore Lane Madison , WI 53718-2148 www.alliantenergy.com Equity dilution Credit loss charge on guarantees for affiliate of Whiting Petroleum in 2020 Other Total Non - GAAP EPS 2021 $ 0.66 0.03 ( 0.01 ) $ 0.68 " We had a solid start to the year with more than 25 % of our 2021 guidance midpoint coming in the first quarter , and we are reaffirming our 2021 guidance range of $ 2.50 to $ 2.64 " said John Larsen , Alliant Energy Chair , President and CEO . " We are also excited to have achieved another major milestone in our purpose - driven clean energy transition , receiving approval last month for the first 675 megawatts of our nearly 1,100 megawatt proposed solar expansion in Wisconsin . " 2020 Utilities and Corporate Services - Alliant Energy's Utilities and Alliant Energy Corporate Services , Inc. ( Corporate Services ) operations generated $ 0.66 per share of GAAP EPS in the first quarter of 2021 , which was $ 0.06 per share lower than the first quarter of 2020 . The primary drivers of lower EPS were timing of income tax expense , higher depreciation expense and lower allowance for funds used during construction in the first quarter of 2021. These impacts were partially offset by higher earnings resulting from IPL's and WPL's increasing rate base and higher electric and gas sales volumes largely caused by colder temperatures in the first quarter of 2021 compared to last year . $ 0.72 0.03 ( 0.03 ) $ 0.72 Non - utility and Parent - Alliant Energy's Non - utility and Parent operations generated ( $ 0.01 ) per share of GAAP EPS in the first quarter of 2021 , which was a $ 0.04 per share earnings increase compared to the first quarter of 2020. The higher EPS was primarily driven by a $ 0.02 per share credit loss charge in the first quarter of 2020 related to guarantees associated with an affiliate of Whiting Petroleum Corporation ( Whiting Petroleum ) . Earnings Adjustments - Non - GAAP EPS for the three months ended March 31 , 2020 excludes charges of $ 0.02 per share related to the credit loss charge described above for Alliant Energy's Non - utility and Parent . Non - GAAP adjustments , which relate to material charges or income that are not normally associated with ongoing operations , are provided as a supplement to results reported in accordance with GAAP . Details regarding GAAP EPS variances between the first quarters of 2021 and 2020 for Alliant Energy are as follows : Variance $ 0.08 ( 0.05 ) ( 0.05 ) ( 0.05 ) 0.04 ( 0.02 ) 0.02 0.01 ( $ 0.02 )