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v3.22.2.2

Regulatory Matters (Tables) | 9 Months Ended
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Sep. 30, 2022
Regulatory Assets [Line Items] |
Regulatory Assets | Regulatory assets were comprised of the following items (in millions):
| Alliant Energy |  | IPL |  | WPL
| September 30, 2022 |  | December 31, 2021 |  | September 30, 2022 |  | December 31, 2021 |  | September 30, 2022 |  | December 31, 2021
Tax-related | $913 |  | $934 |  | $842 |  | $884 |  | $71 |  | $50
Pension and OPEB costs | 436 |  | 462 |  | 216 |  | 228 |  | 220 |  | 234
Asset retirement obligations | 145 |  | 128 |  | 104 |  | 89 |  | 41 |  | 39
Commodity cost recovery | 129 |  | 42 |  | 2 |  | 2 |  | 127 |  | 40
Derivatives | 102 |  | 8 |  | 67 |  | 4 |  | 35 |  | 4
Assets retired early | 75 |  | 92 |  | 56 |  | 66 |  | 19 |  | 26
IPL’s DAEC PPA amendment | 72 |  | 90 |  | 72 |  | 90 |  | — |  | —
WPL’s Western Wisconsin gas distribution expansion investments | 49 |  | 52 |  | — |  | — |  | 49 |  | 52
Other | 120 |  | 132 |  | 64 |  | 80 |  | 56 |  | 52
| $2,041 |  | $1,940 |  | $1,423 |  | $1,443 |  | $618 |  | $497
Regulatory Liabilities | Regulatory liabilities were comprised of the following items (in millions):
| Alliant Energy |  | IPL |  | WPL
| September 30, 2022 |  | December 31, 2021 |  | September 30, 2022 |  | December 31, 2021 |  | September 30, 2022 |  | December 31, 2021
Tax-related | $582 |  | $585 |  | $304 |  | $312 |  | $278 |  | $273
Cost of removal obligations | 398 |  | 384 |  | 258 |  | 252 |  | 140 |  | 132
Derivatives | 312 |  | 166 |  | 164 |  | 77 |  | 148 |  | 89
WPL’s West Riverside liquidated damages | 33 |  | 36 |  | — |  | — |  | 33 |  | 36
Electric transmission cost recovery | 16 |  | 51 |  | 4 |  | 27 |  | 12 |  | 24
Other | 46 |  | 49 |  | 31 |  | 23 |  | 15 |  | 26
| $1,387 |  | $1,271 |  | $761 |  | $691 |  | $626 |  | $580
IPL [Member] |
Regulatory Assets [Line Items] |
Regulatory Assets | Regulatory assets were comprised of the following items (in millions):
| Alliant Energy |  | IPL |  | WPL
| September 30, 2022 |  | December 31, 2021 |  | September 30, 2022 |  | December 31, 2021 |  | September 30, 2022 |  | December 31, 2021
Tax-related | $913 |  | $934 |  | $842 |  | $884 |  | $71 |  | $50
Pension and OPEB costs | 436 |  | 462 |  | 216 |  | 228 |  | 220 |  | 234
Asset retirement obligations | 145 |  | 128 |  | 104 |  | 89 |  | 41 |  | 39
Commodity cost recovery | 129 |  | 42 |  | 2 |  | 2 |  | 127 |  | 40
Derivatives | 102 |  | 8 |  | 67 |  | 4 |  | 35 |  | 4
Assets retired early | 75 |  | 92 |  | 56 |  | 66 |  | 19 |  | 26
IPL’s DAEC PPA amendment | 72 |  | 90 |  | 72 |  | 90 |  | — |  | —
WPL’s Western Wisconsin gas distribution expansion investments | 49 |  | 52 |  | — |  | — |  | 49 |  | 52
Other | 120 |  | 132 |  | 64 |  | 80 |  | 56 |  | 52
| $2,041 |  | $1,940 |  | $1,423 |  | $1,443 |  | $618 |  | $497
Regulatory Liabilities | Regulatory liabilities were comprised of the following items (in millions):
| Alliant Energy |  | IPL |  | WPL
| September 30, 2022 |  | December 31, 2021 |  | September 30, 2022 |  | December 31, 2021 |  | September 30, 2022 |  | December 31, 2021
Tax-related | $582 |  | $585 |  | $304 |  | $312 |  | $278 |  | $273
Cost of removal obligations | 398 |  | 384 |  | 258 |  | 252 |  | 140 |  | 132
Derivatives | 312 |  | 166 |  | 164 |  | 77 |  | 148 |  | 89
WPL’s West Riverside liquidated damages | 33 |  | 36 |  | — |  | — |  | 33 |  | 36
Electric transmission cost recovery | 16 |  | 51 |  | 4 |  | 27 |  | 12 |  | 24
Other | 46 |  | 49 |  | 31 |  | 23 |  | 15 |  | 26
| $1,387 |  | $1,271 |  | $761 |  | $691 |  | $626 |  | $580
WPL [Member] |
Regulatory Assets [Line Items] |
Regulatory Assets | Regulatory assets were comprised of the following items (in millions):
| Alliant Energy |  | IPL |  | WPL
| September 30, 2022 |  | December 31, 2021 |  | September 30, 2022 |  | December 31, 2021 |  | September 30, 2022 |  | December 31, 2021
Tax-related | $913 |  | $934 |  | $842 |  | $884 |  | $71 |  | $50
Pension and OPEB costs | 436 |  | 462 |  | 216 |  | 228 |  | 220 |  | 234
Asset retirement obligations | 145 |  | 128 |  | 104 |  | 89 |  | 41 |  | 39
Commodity cost recovery | 129 |  | 42 |  | 2 |  | 2 |  | 127 |  | 40
Derivatives | 102 |  | 8 |  | 67 |  | 4 |  | 35 |  | 4
Assets retired early | 75 |  | 92 |  | 56 |  | 66 |  | 19 |  | 26
IPL’s DAEC PPA amendment | 72 |  | 90 |  | 72 |  | 90 |  | — |  | —
WPL’s Western Wisconsin gas distribution expansion investments | 49 |  | 52 |  | — |  | — |  | 49 |  | 52
Other | 120 |  | 132 |  | 64 |  | 80 |  | 56 |  | 52
| $2,041 |  | $1,940 |  | $1,423 |  | $1,443 |  | $618 |  | $497
Regulatory Liabilities | Regulatory liabilities were comprised of the following items (in millions):
| Alliant Energy |  | IPL |  | WPL
| September 30, 2022 |  | December 31, 2021 |  | September 30, 2022 |  | December 31, 2021 |  | September 30, 2022 |  | December 31, 2021
Tax-related | $582 |  | $585 |  | $304 |  | $312 |  | $278 |  | $273
Cost of removal obligations | 398 |  | 384 |  | 258 |  | 252 |  | 140 |  | 132
Derivatives | 312 |  | 166 |  | 164 |  | 77 |  | 148 |  | 89
WPL’s West Riverside liquidated damages | 33 |  | 36 |  | — |  | — |  | 33 |  | 36
Electric transmission cost recovery | 16 |  | 51 |  | 4 |  | 27 |  | 12 |  | 24
Other | 46 |  | 49 |  | 31 |  | 23 |  | 15 |  | 26
| $1,387 |  | $1,271 |  | $761 |  | $691 |  | $626 |  | $580

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