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Commitments And Contingencies | 12 Months Ended
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Dec. 31, 2020
Commitments And Contingencies | COMMITMENTS AND CONTINGENCIES(a) Capital Purchase Commitments - Various contractual obligations contain minimum future commitments related to capital expenditures for certain construction projects, including WPL’s expansion of solar generation. At December 31, 2020, Alliant Energy’s and WPL’s minimum future commitments in 2021 for these projects were $8 million and $7 million, respectively.(b) Other Purchase Commitments - Various commodity supply, transportation and storage contracts help meet obligations to provide electricity and natural gas to utility customers. In addition, there are various purchase commitments associated with other goods and services. At December 31, 2020, the related minimum future commitments were as follows (in millions):
Alliant Energy | 2021 |  | 2022 |  | 2023 |  | 2024 |  | 2025 |  | Thereafter |  | Total
Natural gas | 252 |  | 174 |  | 137 |  | 105 |  | 68 |  | 185 |  | 921
Coal | 70 |  | 27 |  | 17 |  | — |  | — |  | — |  | 114
Other (a) | 61 |  | 17 |  | 11 |  | 8 |  | 3 |  | 29 |  | 129
| $383 |  | $218 |  | $165 |  | $113 |  | $71 |  | $214 |  | $1,164
IPL | 2021 |  | 2022 |  | 2023 |  | 2024 |  | 2025 |  | Thereafter |  | Total
Natural gas | 130 |  | 88 |  | 79 |  | 68 |  | 38 |  | 71 |  | 474
Coal | 32 |  | 16 |  | 13 |  | — |  | — |  | — |  | 61
Other (a) | 25 |  | 5 |  | 4 |  | 2 |  | 2 |  | 27 |  | 65
| $187 |  | $109 |  | $96 |  | $70 |  | $40 |  | $98 |  | $600
WPL | 2021 |  | 2022 |  | 2023 |  | 2024 |  | 2025 |  | Thereafter |  | Total
Natural gas | 122 |  | 86 |  | 58 |  | 37 |  | 30 |  | 114 |  | 447
Coal | 38 |  | 11 |  | 4 |  | — |  | — |  | — |  | 53
Other (a) | 26 |  | 2 |  | 1 |  | 1 |  | 1 |  | 1 |  | 32
| $186 |  | $99 |  | $63 |  | $38 |  | $31 |  | $115 |  | $532
(a)Includes individual commitments incurred during the normal course of business that exceeded $1 million at December 31, 2020. (c) Legal Proceedings - Alliant Energy, IPL and WPL are involved in legal and administrative proceedings before various courts and agencies with respect to matters arising in the ordinary course of business. Although unable to predict the outcome of these matters, Alliant Energy, IPL and WPL believe that appropriate reserves have been established and final disposition of these actions will not have a material effect on their financial condition or results of operations.(d) Guarantees and Indemnifications - Whiting Petroleum - Whiting Petroleum is an independent oil and gas company. In 2004, Alliant Energy sold its remaining interest in Whiting Petroleum. Alliant Energy Resources, LLC, as the successor to a predecessor entity that owned Whiting Petroleum, and a wholly-owned subsidiary of AEF, continues to guarantee the partnership obligations of an affiliate of Whiting Petroleum under multiple general partnership agreements in the oil and gas industry. The guarantees do not include a maximum limit. Based on information made available to Alliant Energy by Whiting Petroleum, the Whiting Petroleum affiliate holds an approximate 6% share in the partnerships, and currently known obligations include costs associated with the future abandonment of certain facilities owned by the partnerships. The general partnerships were formed under California law, and Alliant Energy Resources, LLC may need to perform under the guarantees if the affiliate of Whiting Petroleum is unable to meet its partnership obligations. As of December 31, 2020, the currently known partnership obligations for the abandonment obligations are estimated at $68 million, which represents Alliant Energy’s currently estimated maximum exposure under the guarantees. Alliant Energy estimates its expected loss to be a portion of the $68 million of known partnership abandonment obligations of the Whiting Petroleum affiliate and the other partners. Alliant Energy is not aware of any material liabilities related to these guarantees that it is probable that it will be obligated to pay; however, the new credit loss accounting standard adopted on January 1, 2020 requires recognition of a liability for expected credit losses related to the contingent obligations that are in the scope of these guarantees. With the adoption of this standard, Alliant Energy recorded a pre-tax $12 million cumulative effect adjustment to decrease the opening balance of retained earnings as of January 1, 2020. In April 2020, Whiting Petroleum filed for bankruptcy, and in September 2020, Whiting Petroleum completed its reorganization and emerged from bankruptcy. As a result of Whiting Petroleum’s completed bankruptcy proceedings, as well as additional information regarding the guarantees obtained from the bankruptcy proceedings, the credit loss liability was decreased to $5 million in 2020. The credit loss liability is recorded in “Other liabilities” on Alliant Energy’s balance sheet as of December 31, 2020. In 2020, the pre-tax credit loss adjustment of $7 million was recorded as a reduction in Alliant Energy’s “Other operation and maintenance” expenses. Non-utility Wind Farm in Oklahoma - In 2017, a wholly-owned subsidiary of AEF acquired a cash equity ownership interest in a non-utility wind farm located in Oklahoma. The wind farm provides electricity to a third-party under a long-term PPA. Alliant Energy provided a parent guarantee of its subsidiary’s indemnification obligations under the related operating agreement and PPA. Alliant Energy’s obligations under the operating agreement were $74 million as of December 31, 2020 and will reduce annually until expiring in July 2047. Alliant Energy’s obligations under the PPA are subject to a maximum limit of $17 million and expire in December 2031, subject to potential extension. Alliant Energy is not aware of any material liabilities related to this guarantee that it is probable that it will be obligated to pay and therefore has not recognized any material liabilities related to this guarantee as of December 31, 2020 and 2019. (e) Environmental Matters - Alliant Energy, IPL and WPL are subject to environmental regulations as a result of their current and past operations. These regulations are designed to protect public health and the environment and have resulted in compliance, remediation, containment and monitoring obligations, which are recorded as current and non-current environmental liabilities. Substantially all of the environmental liabilities recorded on the balance sheets relate to MGP sites.MGP Sites - IPL and WPL have current or previous ownership interests in various sites that are previously associated with the production of gas for which IPL and WPL have, or may have in the future, liability for investigation, remediation and monitoring costs. IPL and WPL are working pursuant to the requirements of various federal and state agencies to investigate, mitigate, prevent and remediate, where necessary, the environmental impacts to property, including natural resources, at and around these former MGP sites in order to protect public health and the environment. At December 31, 2020, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, which are not discounted, were as follows (in millions). At December 31, 2020, such amounts for WPL were not material.
| Alliant Energy |  | IPL
Range of estimated future costs | $11 |  | - | $28 |  | $8 |  | - | $22
Current and non-current environmental liabilities | 15 |  | 12
IPL Consent Decree - In 2015, the U.S. District Court for the Northern District of Iowa approved a Consent Decree that IPL entered into with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa, thereby resolving potential CAA issues associated with emissions from IPL’s coal-fired generating facilities in Iowa. IPL has completed various requirements under the Consent Decree. IPL’s remaining requirements include fuel switching or retiring Burlington by December 31, 2021 and Prairie Creek Units 1 and 3 by December 31, 2025. Alliant Energy and IPL currently expect to recover material costs incurred by IPL related to compliance with the terms of the Consent Decree from IPL’s electric customers. Other Environmental Contingencies - In addition to the environmental liabilities discussed above, various environmental rules are monitored that may have a significant impact on future operations. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Given uncertainties regarding the outcome, timing and compliance plans for these environmental matters, the complete financial impact of each of these rules is not able to be determined; however future capital investments and/or modifications to EGUs and electric and gas distribution systems to comply with certain of these rules could be significant. Specific current, proposed or potential environmental matters include, among others: Effluent Limitation Guidelines, CCR Rule, and various legislation and EPA regulations to monitor and regulate the emission of GHG, including the CAA. (f) Credit Risk - IPL provides retail electric and gas services in Iowa and wholesale electric service in Minnesota, Illinois and Iowa. WPL provides retail electric and gas services and wholesale electric service in Wisconsin. The geographic concentration of IPL’s and WPL’s customers did not contribute significantly to overall credit risk exposure. In addition, as a result of a diverse customer base, IPL and WPL did not have any significant credit risk concentration for receivables arising from the sale of electricity or gas services. Alliant Energy, IPL and WPL are subject to credit risk related to the ability of counterparties to meet their contractual payment obligations or the potential non-performance of counterparties to deliver contracted commodities and other goods or services at the contracted price. Credit policies are maintained to mitigate credit risk. These credit policies include evaluation of the financial condition of certain counterparties, use of credit risk-related contingent provisions in certain agreements that require credit support from counterparties not meeting specific criteria, diversification of counterparties to reduce concentrations of credit risk and the use of standardized agreements that facilitate the netting of cash flows associated with certain counterparties. Based on these credit policies and counterparty diversification, as well as utility cost recovery mechanisms, it is unlikely that counterparty non-performance would have a material effect on financial condition or results of operations. However, there is no assurance that these items will protect against all losses from counterparty non-performance. Refer to Notes 5(a) and 15 for details of allowances for expected credit losses and credit risk-related contingent features, respectively. (g) MISO Transmission Owner Return on Equity Complaints - A group of MISO cooperative and municipal utilities previously filed complaints with FERC requesting a reduction to the base return on equity used by MISO transmission owners, including ITC and ATC. The first complaint covered the period from November 12, 2013 through February 11, 2015. In 2017, IPL and WPL received refunds related to the first complaint period, which were subsequently refunded to their retail and wholesale customers. The second complaint covered the period from February 12, 2015 through May 11, 2016. In November 2019, FERC issued an order on the previously filed complaints and reduced the base return on equity used by the MISO transmission owners to 9.88% effective for the first complaint period and subsequent to September 28, 2016. The November 2019 FERC order also dismissed the second complaint; therefore, FERC did not direct refunds to be made for that complaint. In May 2020, FERC issued an order in response to various rehearing requests and increased the base return on equity used by the MISO transmission owners from 9.88% to 10.02% for the first complaint period and subsequent to September 28, 2016, which reduces the refunds originally anticipated to be received by IPL and WPL as a result of FERC’s November 2019 order.In 2020, IPL and WPL received $15 million and $5 million, respectively, in refunds related to the FERC orders. In October 2020, FERC extended the time to complete additional refunds to September 2021. IPL currently expects that all refunds will be returned to its retail electric customers after refund amounts and timing are known and a refund plan is approved by the IUB. IPL currently expects that a portion of the refunds will be returned to its retail electric customers in 2021. Pursuant to PSCW authorization, WPL will retain the refunds to maintain its current retail electric base rates through the end of 2021. WPL currently expects that any refunds not utilized to maintain base rates would be returned to its customers in WPL’s next retail electric rate review proceeding. Any further changes in FERC’s decisions may have an impact on Alliant Energy’s share of ATC’s future earnings and customer costs.
IPL [Member] |
Commitments And Contingencies | COMMITMENTS AND CONTINGENCIES(b) Other Purchase Commitments - Various commodity supply, transportation and storage contracts help meet obligations to provide electricity and natural gas to utility customers. In addition, there are various purchase commitments associated with other goods and services. At December 31, 2020, the related minimum future commitments were as follows (in millions):
Alliant Energy | 2021 |  | 2022 |  | 2023 |  | 2024 |  | 2025 |  | Thereafter |  | Total
Natural gas | 252 |  | 174 |  | 137 |  | 105 |  | 68 |  | 185 |  | 921
Coal | 70 |  | 27 |  | 17 |  | — |  | — |  | — |  | 114
Other (a) | 61 |  | 17 |  | 11 |  | 8 |  | 3 |  | 29 |  | 129
| $383 |  | $218 |  | $165 |  | $113 |  | $71 |  | $214 |  | $1,164
IPL | 2021 |  | 2022 |  | 2023 |  | 2024 |  | 2025 |  | Thereafter |  | Total
Natural gas | 130 |  | 88 |  | 79 |  | 68 |  | 38 |  | 71 |  | 474
Coal | 32 |  | 16 |  | 13 |  | — |  | — |  | — |  | 61
Other (a) | 25 |  | 5 |  | 4 |  | 2 |  | 2 |  | 27 |  | 65
| $187 |  | $109 |  | $96 |  | $70 |  | $40 |  | $98 |  | $600
WPL | 2021 |  | 2022 |  | 2023 |  | 2024 |  | 2025 |  | Thereafter |  | Total
Natural gas | 122 |  | 86 |  | 58 |  | 37 |  | 30 |  | 114 |  | 447
Coal | 38 |  | 11 |  | 4 |  | — |  | — |  | — |  | 53
Other (a) | 26 |  | 2 |  | 1 |  | 1 |  | 1 |  | 1 |  | 32
| $186 |  | $99 |  | $63 |  | $38 |  | $31 |  | $115 |  | $532
(a)Includes individual commitments incurred during the normal course of business that exceeded $1 million at December 31, 2020. (c) Legal Proceedings - Alliant Energy, IPL and WPL are involved in legal and administrative proceedings before various courts and agencies with respect to matters arising in the ordinary course of business. Although unable to predict the outcome of these matters, Alliant Energy, IPL and WPL believe that appropriate reserves have been established and final disposition of these actions will not have a material effect on their financial condition or results of operations.(e) Environmental Matters - Alliant Energy, IPL and WPL are subject to environmental regulations as a result of their current and past operations. These regulations are designed to protect public health and the environment and have resulted in compliance, remediation, containment and monitoring obligations, which are recorded as current and non-current environmental liabilities. Substantially all of the environmental liabilities recorded on the balance sheets relate to MGP sites.MGP Sites - IPL and WPL have current or previous ownership interests in various sites that are previously associated with the production of gas for which IPL and WPL have, or may have in the future, liability for investigation, remediation and monitoring costs. IPL and WPL are working pursuant to the requirements of various federal and state agencies to investigate, mitigate, prevent and remediate, where necessary, the environmental impacts to property, including natural resources, at and around these former MGP sites in order to protect public health and the environment. At December 31, 2020, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, which are not discounted, were as follows (in millions). At December 31, 2020, such amounts for WPL were not material.
| Alliant Energy |  | IPL
Range of estimated future costs | $11 |  | - | $28 |  | $8 |  | - | $22
Current and non-current environmental liabilities | 15 |  | 12
IPL Consent Decree - In 2015, the U.S. District Court for the Northern District of Iowa approved a Consent Decree that IPL entered into with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa, thereby resolving potential CAA issues associated with emissions from IPL’s coal-fired generating facilities in Iowa. IPL has completed various requirements under the Consent Decree. IPL’s remaining requirements include fuel switching or retiring Burlington by December 31, 2021 and Prairie Creek Units 1 and 3 by December 31, 2025. Alliant Energy and IPL currently expect to recover material costs incurred by IPL related to compliance with the terms of the Consent Decree from IPL’s electric customers. Other Environmental Contingencies - In addition to the environmental liabilities discussed above, various environmental rules are monitored that may have a significant impact on future operations. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Given uncertainties regarding the outcome, timing and compliance plans for these environmental matters, the complete financial impact of each of these rules is not able to be determined; however future capital investments and/or modifications to EGUs and electric and gas distribution systems to comply with certain of these rules could be significant. Specific current, proposed or potential environmental matters include, among others: Effluent Limitation Guidelines, CCR Rule, and various legislation and EPA regulations to monitor and regulate the emission of GHG, including the CAA. (f) Credit Risk - IPL provides retail electric and gas services in Iowa and wholesale electric service in Minnesota, Illinois and Iowa. WPL provides retail electric and gas services and wholesale electric service in Wisconsin. The geographic concentration of IPL’s and WPL’s customers did not contribute significantly to overall credit risk exposure. In addition, as a result of a diverse customer base, IPL and WPL did not have any significant credit risk concentration for receivables arising from the sale of electricity or gas services. Alliant Energy, IPL and WPL are subject to credit risk related to the ability of counterparties to meet their contractual payment obligations or the potential non-performance of counterparties to deliver contracted commodities and other goods or services at the contracted price. Credit policies are maintained to mitigate credit risk. These credit policies include evaluation of the financial condition of certain counterparties, use of credit risk-related contingent provisions in certain agreements that require credit support from counterparties not meeting specific criteria, diversification of counterparties to reduce concentrations of credit risk and the use of standardized agreements that facilitate the netting of cash flows associated with certain counterparties. Based on these credit policies and counterparty diversification, as well as utility cost recovery mechanisms, it is unlikely that counterparty non-performance would have a material effect on financial condition or results of operations. However, there is no assurance that these items will protect against all losses from counterparty non-performance. Refer to Notes 5(a) and 15 for details of allowances for expected credit losses and credit risk-related contingent features, respectively. (g) MISO Transmission Owner Return on Equity Complaints - A group of MISO cooperative and municipal utilities previously filed complaints with FERC requesting a reduction to the base return on equity used by MISO transmission owners, including ITC and ATC. The first complaint covered the period from November 12, 2013 through February 11, 2015. In 2017, IPL and WPL received refunds related to the first complaint period, which were subsequently refunded to their retail and wholesale customers. The second complaint covered the period from February 12, 2015 through May 11, 2016. In November 2019, FERC issued an order on the previously filed complaints and reduced the base return on equity used by the MISO transmission owners to 9.88% effective for the first complaint period and subsequent to September 28, 2016. The November 2019 FERC order also dismissed the second complaint; therefore, FERC did not direct refunds to be made for that complaint. In May 2020, FERC issued an order in response to various rehearing requests and increased the base return on equity used by the MISO transmission owners from 9.88% to 10.02% for the first complaint period and subsequent to September 28, 2016, which reduces the refunds originally anticipated to be received by IPL and WPL as a result of FERC’s November 2019 order.In 2020, IPL and WPL received $15 million and $5 million, respectively, in refunds related to the FERC orders. In October 2020, FERC extended the time to complete additional refunds to September 2021. IPL currently expects that all refunds will be returned to its retail electric customers after refund amounts and timing are known and a refund plan is approved by the IUB. IPL currently expects that a portion of the refunds will be returned to its retail electric customers in 2021. Pursuant to PSCW authorization, WPL will retain the refunds to maintain its current retail electric base rates through the end of 2021. WPL currently expects that any refunds not utilized to maintain base rates would be returned to its customers in WPL’s next retail electric rate review proceeding. Any further changes in FERC’s decisions may have an impact on Alliant Energy’s share of ATC’s future earnings and customer costs.
WPL [Member] |
Commitments And Contingencies | COMMITMENTS AND CONTINGENCIES(a) Capital Purchase Commitments - Various contractual obligations contain minimum future commitments related to capital expenditures for certain construction projects, including WPL’s expansion of solar generation. At December 31, 2020, Alliant Energy’s and WPL’s minimum future commitments in 2021 for these projects were $8 million and $7 million, respectively.(b) Other Purchase Commitments - Various commodity supply, transportation and storage contracts help meet obligations to provide electricity and natural gas to utility customers. In addition, there are various purchase commitments associated with other goods and services. At December 31, 2020, the related minimum future commitments were as follows (in millions):
Alliant Energy | 2021 |  | 2022 |  | 2023 |  | 2024 |  | 2025 |  | Thereafter |  | Total
Natural gas | 252 |  | 174 |  | 137 |  | 105 |  | 68 |  | 185 |  | 921
Coal | 70 |  | 27 |  | 17 |  | — |  | — |  | — |  | 114
Other (a) | 61 |  | 17 |  | 11 |  | 8 |  | 3 |  | 29 |  | 129
| $383 |  | $218 |  | $165 |  | $113 |  | $71 |  | $214 |  | $1,164
IPL | 2021 |  | 2022 |  | 2023 |  | 2024 |  | 2025 |  | Thereafter |  | Total
Natural gas | 130 |  | 88 |  | 79 |  | 68 |  | 38 |  | 71 |  | 474
Coal | 32 |  | 16 |  | 13 |  | — |  | — |  | — |  | 61
Other (a) | 25 |  | 5 |  | 4 |  | 2 |  | 2 |  | 27 |  | 65
| $187 |  | $109 |  | $96 |  | $70 |  | $40 |  | $98 |  | $600
WPL | 2021 |  | 2022 |  | 2023 |  | 2024 |  | 2025 |  | Thereafter |  | Total
Natural gas | 122 |  | 86 |  | 58 |  | 37 |  | 30 |  | 114 |  | 447
Coal | 38 |  | 11 |  | 4 |  | — |  | — |  | — |  | 53
Other (a) | 26 |  | 2 |  | 1 |  | 1 |  | 1 |  | 1 |  | 32
| $186 |  | $99 |  | $63 |  | $38 |  | $31 |  | $115 |  | $532
(a)Includes individual commitments incurred during the normal course of business that exceeded $1 million at December 31, 2020. (c) Legal Proceedings - Alliant Energy, IPL and WPL are involved in legal and administrative proceedings before various courts and agencies with respect to matters arising in the ordinary course of business. Although unable to predict the outcome of these matters, Alliant Energy, IPL and WPL believe that appropriate reserves have been established and final disposition of these actions will not have a material effect on their financial condition or results of operations.(e) Environmental Matters - Alliant Energy, IPL and WPL are subject to environmental regulations as a result of their current and past operations. These regulations are designed to protect public health and the environment and have resulted in compliance, remediation, containment and monitoring obligations, which are recorded as current and non-current environmental liabilities. Substantially all of the environmental liabilities recorded on the balance sheets relate to MGP sites.MGP Sites - IPL and WPL have current or previous ownership interests in various sites that are previously associated with the production of gas for which IPL and WPL have, or may have in the future, liability for investigation, remediation and monitoring costs. IPL and WPL are working pursuant to the requirements of various federal and state agencies to investigate, mitigate, prevent and remediate, where necessary, the environmental impacts to property, including natural resources, at and around these former MGP sites in order to protect public health and the environment. At December 31, 2020, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, which are not discounted, were as follows (in millions). At December 31, 2020, such amounts for WPL were not material.
| Alliant Energy |  | IPL
Range of estimated future costs | $11 |  | - | $28 |  | $8 |  | - | $22
Current and non-current environmental liabilities | 15 |  | 12
IPL Consent Decree - In 2015, the U.S. District Court for the Northern District of Iowa approved a Consent Decree that IPL entered into with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa, thereby resolving potential CAA issues associated with emissions from IPL’s coal-fired generating facilities in Iowa. IPL has completed various requirements under the Consent Decree. IPL’s remaining requirements include fuel switching or retiring Burlington by December 31, 2021 and Prairie Creek Units 1 and 3 by December 31, 2025. Alliant Energy and IPL currently expect to recover material costs incurred by IPL related to compliance with the terms of the Consent Decree from IPL’s electric customers. Other Environmental Contingencies - In addition to the environmental liabilities discussed above, various environmental rules are monitored that may have a significant impact on future operations. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Given uncertainties regarding the outcome, timing and compliance plans for these environmental matters, the complete financial impact of each of these rules is not able to be determined; however future capital investments and/or modifications to EGUs and electric and gas distribution systems to comply with certain of these rules could be significant. Specific current, proposed or potential environmental matters include, among others: Effluent Limitation Guidelines, CCR Rule, and various legislation and EPA regulations to monitor and regulate the emission of GHG, including the CAA. (f) Credit Risk - IPL provides retail electric and gas services in Iowa and wholesale electric service in Minnesota, Illinois and Iowa. WPL provides retail electric and gas services and wholesale electric service in Wisconsin. The geographic concentration of IPL’s and WPL’s customers did not contribute significantly to overall credit risk exposure. In addition, as a result of a diverse customer base, IPL and WPL did not have any significant credit risk concentration for receivables arising from the sale of electricity or gas services. Alliant Energy, IPL and WPL are subject to credit risk related to the ability of counterparties to meet their contractual payment obligations or the potential non-performance of counterparties to deliver contracted commodities and other goods or services at the contracted price. Credit policies are maintained to mitigate credit risk. These credit policies include evaluation of the financial condition of certain counterparties, use of credit risk-related contingent provisions in certain agreements that require credit support from counterparties not meeting specific criteria, diversification of counterparties to reduce concentrations of credit risk and the use of standardized agreements that facilitate the netting of cash flows associated with certain counterparties. Based on these credit policies and counterparty diversification, as well as utility cost recovery mechanisms, it is unlikely that counterparty non-performance would have a material effect on financial condition or results of operations. However, there is no assurance that these items will protect against all losses from counterparty non-performance. Refer to Notes 5(a) and 15 for details of allowances for expected credit losses and credit risk-related contingent features, respectively. (g) MISO Transmission Owner Return on Equity Complaints - A group of MISO cooperative and municipal utilities previously filed complaints with FERC requesting a reduction to the base return on equity used by MISO transmission owners, including ITC and ATC. The first complaint covered the period from November 12, 2013 through February 11, 2015. In 2017, IPL and WPL received refunds related to the first complaint period, which were subsequently refunded to their retail and wholesale customers. The second complaint covered the period from February 12, 2015 through May 11, 2016. In November 2019, FERC issued an order on the previously filed complaints and reduced the base return on equity used by the MISO transmission owners to 9.88% effective for the first complaint period and subsequent to September 28, 2016. The November 2019 FERC order also dismissed the second complaint; therefore, FERC did not direct refunds to be made for that complaint. In May 2020, FERC issued an order in response to various rehearing requests and increased the base return on equity used by the MISO transmission owners from 9.88% to 10.02% for the first complaint period and subsequent to September 28, 2016, which reduces the refunds originally anticipated to be received by IPL and WPL as a result of FERC’s November 2019 order.In 2020, IPL and WPL received $15 million and $5 million, respectively, in refunds related to the FERC orders. In October 2020, FERC extended the time to complete additional refunds to September 2021. IPL currently expects that all refunds will be returned to its retail electric customers after refund amounts and timing are known and a refund plan is approved by the IUB. IPL currently expects that a portion of the refunds will be returned to its retail electric customers in 2021. Pursuant to PSCW authorization, WPL will retain the refunds to maintain its current retail electric base rates through the end of 2021. WPL currently expects that any refunds not utilized to maintain base rates would be returned to its customers in WPL’s next retail electric rate review proceeding. Any further changes in FERC’s decisions may have an impact on Alliant Energy’s share of ATC’s future earnings and customer costs.

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