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v3.24.3

Debt | 9 Months Ended
--- | ---
Sep. 30, 2024
Debt [Line Items] |
Debt | DEBT NOTE 7(a) Short-term Debt - In June 2024, Alliant Energy, IPL and WPL reallocated credit facility capacity amounts to $450 million for Alliant Energy at the parent company level, $250 million for IPL and $300 million for WPL, within the $1 billion total commitment. Information regarding commercial paper classified as short-term debt was as follows (dollars in millions):
September 30, 2024 | Alliant Energy |  | IPL |  | WPL
Amount outstanding | $330 |  | $— |  | $—
Weighted average interest rates | 5.0% |  | —% |  | —%
Available credit facility capacity | $670 |  | $250 |  | $300
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023
Maximum amount outstanding (based on daily outstanding balances) | $330 |  | $474 |  | $— |  | $7 |  | $— |  | $125
Average amount outstanding (based on daily outstanding balances) | $197 |  | $440 |  | $— |  | $— |  | $— |  | $86
Weighted average interest rates | 5.4% |  | 5.5% |  | —% |  | 5.5% |  | —% |  | 5.4%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $632 |  | $793 |  | $19 |  | $70 |  | $390 |  | $349
Average amount outstanding (based on daily outstanding balances) | $320 |  | $367 |  | $1 |  | $2 |  | $87 |  | $135
Weighted average interest rates | 5.5% |  | 5.1% |  | 5.5% |  | 5.3% |  | 5.5% |  | 4.9%
NOTE 7(b) Long-term Debt - In March 2024, AEF entered into a $300 million variable rate (6% as of September 30, 2024) term loan credit agreement (with Alliant Energy as guarantor), which expires in March 2025. This term loan credit agreement amends and restates the term loan credit agreement that expired in March 2024, and retired the $300 million variable rate term loan set forth therein. AEF’s restated term loan credit agreement includes an option to increase the amount outstanding with one or more additional term loans in an aggregate amount not to exceed $100 million. In June 2024, AEF issued $375 million of 5.4% senior notes due 2027 (with Alliant Energy as guarantor). The net proceeds from this issuance were used to reduce Alliant Energy’s outstanding commercial paper and for general corporate purposes. In September 2024, IPL issued $350 million of 4.95% senior debentures due 2034 and $300 million of 5.45% senior debentures due 2054. A portion of the net proceeds from this issuance were placed in time deposits and money market fund investments pending the December 2024 retirement of IPL’s $500 million 3.25% senior debentures, and the remainder of the net proceeds were used for general corporate purposes. In March 2024, WPL issued $300 million of 5.375% debentures due 2034. WPL’s debentures were issued as green bonds, and an amount equal to or in excess of the net proceeds was disbursed for the development and acquisition of its solar EGUs. Convertible Senior Notes - As of September 30, 2024, the conditions allowing holders of Alliant Energy’s convertible senior notes due 2026 (the Notes) to convert their Notes were not met, and as a result, the Notes were classified as “Long-term debt, net” on Alliant Energy’s balance sheet. As of September 30, 2024, the net carrying amount of the Notes was $570 million, with unamortized debt issuance costs of $5 million, and the estimated fair value (Level 2) of the Notes was $602 million. As of September 30, 2024, there were no shares of Alliant Energy’s common stock related to the potential conversion of the Notes included in diluted EPS based on Alliant Energy’s average stock prices and the relevant terms of the Notes.
IPL [Member] |
Debt [Line Items] |
Debt | DEBT NOTE 7(a) Short-term Debt - In June 2024, Alliant Energy, IPL and WPL reallocated credit facility capacity amounts to $450 million for Alliant Energy at the parent company level, $250 million for IPL and $300 million for WPL, within the $1 billion total commitment. Information regarding commercial paper classified as short-term debt was as follows (dollars in millions):
September 30, 2024 | Alliant Energy |  | IPL |  | WPL
Amount outstanding | $330 |  | $— |  | $—
Weighted average interest rates | 5.0% |  | —% |  | —%
Available credit facility capacity | $670 |  | $250 |  | $300
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023
Maximum amount outstanding (based on daily outstanding balances) | $330 |  | $474 |  | $— |  | $7 |  | $— |  | $125
Average amount outstanding (based on daily outstanding balances) | $197 |  | $440 |  | $— |  | $— |  | $— |  | $86
Weighted average interest rates | 5.4% |  | 5.5% |  | —% |  | 5.5% |  | —% |  | 5.4%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $632 |  | $793 |  | $19 |  | $70 |  | $390 |  | $349
Average amount outstanding (based on daily outstanding balances) | $320 |  | $367 |  | $1 |  | $2 |  | $87 |  | $135
Weighted average interest rates | 5.5% |  | 5.1% |  | 5.5% |  | 5.3% |  | 5.5% |  | 4.9%
NOTE 7(b) Long-term Debt - In March 2024, AEF entered into a $300 million variable rate (6% as of September 30, 2024) term loan credit agreement (with Alliant Energy as guarantor), which expires in March 2025. This term loan credit agreement amends and restates the term loan credit agreement that expired in March 2024, and retired the $300 million variable rate term loan set forth therein. AEF’s restated term loan credit agreement includes an option to increase the amount outstanding with one or more additional term loans in an aggregate amount not to exceed $100 million. In June 2024, AEF issued $375 million of 5.4% senior notes due 2027 (with Alliant Energy as guarantor). The net proceeds from this issuance were used to reduce Alliant Energy’s outstanding commercial paper and for general corporate purposes. In September 2024, IPL issued $350 million of 4.95% senior debentures due 2034 and $300 million of 5.45% senior debentures due 2054. A portion of the net proceeds from this issuance were placed in time deposits and money market fund investments pending the December 2024 retirement of IPL’s $500 million 3.25% senior debentures, and the remainder of the net proceeds were used for general corporate purposes. In March 2024, WPL issued $300 million of 5.375% debentures due 2034. WPL’s debentures were issued as green bonds, and an amount equal to or in excess of the net proceeds was disbursed for the development and acquisition of its solar EGUs.
WPL [Member] |
Debt [Line Items] |
Debt | DEBT NOTE 7(a) Short-term Debt - In June 2024, Alliant Energy, IPL and WPL reallocated credit facility capacity amounts to $450 million for Alliant Energy at the parent company level, $250 million for IPL and $300 million for WPL, within the $1 billion total commitment. Information regarding commercial paper classified as short-term debt was as follows (dollars in millions):
September 30, 2024 | Alliant Energy |  | IPL |  | WPL
Amount outstanding | $330 |  | $— |  | $—
Weighted average interest rates | 5.0% |  | —% |  | —%
Available credit facility capacity | $670 |  | $250 |  | $300
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2024 |  | 2023 |  | 2024 |  | 2023 |  | 2024 |  | 2023
Maximum amount outstanding (based on daily outstanding balances) | $330 |  | $474 |  | $— |  | $7 |  | $— |  | $125
Average amount outstanding (based on daily outstanding balances) | $197 |  | $440 |  | $— |  | $— |  | $— |  | $86
Weighted average interest rates | 5.4% |  | 5.5% |  | —% |  | 5.5% |  | —% |  | 5.4%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $632 |  | $793 |  | $19 |  | $70 |  | $390 |  | $349
Average amount outstanding (based on daily outstanding balances) | $320 |  | $367 |  | $1 |  | $2 |  | $87 |  | $135
Weighted average interest rates | 5.5% |  | 5.1% |  | 5.5% |  | 5.3% |  | 5.5% |  | 4.9%
NOTE 7(b) Long-term Debt - In March 2024, AEF entered into a $300 million variable rate (6% as of September 30, 2024) term loan credit agreement (with Alliant Energy as guarantor), which expires in March 2025. This term loan credit agreement amends and restates the term loan credit agreement that expired in March 2024, and retired the $300 million variable rate term loan set forth therein. AEF’s restated term loan credit agreement includes an option to increase the amount outstanding with one or more additional term loans in an aggregate amount not to exceed $100 million. In June 2024, AEF issued $375 million of 5.4% senior notes due 2027 (with Alliant Energy as guarantor). The net proceeds from this issuance were used to reduce Alliant Energy’s outstanding commercial paper and for general corporate purposes. In September 2024, IPL issued $350 million of 4.95% senior debentures due 2034 and $300 million of 5.45% senior debentures due 2054. A portion of the net proceeds from this issuance were placed in time deposits and money market fund investments pending the December 2024 retirement of IPL’s $500 million 3.25% senior debentures, and the remainder of the net proceeds were used for general corporate purposes. In March 2024, WPL issued $300 million of 5.375% debentures due 2034. WPL’s debentures were issued as green bonds, and an amount equal to or in excess of the net proceeds was disbursed for the development and acquisition of its solar EGUs.

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