Regulatory Matters

9 Months Ended

Sep. 30, 2022

Public Utilities, General Disclosures [Line Items]

Regulatory Matters

REGULATORY MATTERS

Regulatory Assets and Regulatory Liabilities -

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

Tax-related - Refer to Note 9 for discussion of Iowa Tax Reform, which resulted in a decrease in Alliant Energy’s and IPL’s tax-related regulatory assets in the third quarter of 2022.

Commodity cost recovery - The cost recovery mechanism for WPL’s retail electric customers is based on forecasts of certain fuel-related costs expected to be incurred during forward-looking test periods and fuel monitoring ranges determined by the PSCW during each retail electric rate proceeding or in a separate fuel cost plan approval proceeding. During the nine months ended September 30, 2022, WPL’s actual fuel-related costs fell outside these fuel monitoring ranges, resulting in a $83 million deferral of higher than expected fuel-related costs as of September 30, 2022.

Derivatives - Refer to Note 11 for discussion of changes in Alliant Energy’s, IPL’s and WPL’s derivative liabilities/assets during the nine months ended September 30, 2022, which result in comparable changes to regulatory assets/liabilities on the balance sheets.

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]

Public Utilities, General Disclosures [Line Items]

Regulatory Matters

REGULATORY MATTERS

Regulatory Assets and Regulatory Liabilities -

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

Tax-related - Refer to Note 9 for discussion of Iowa Tax Reform, which resulted in a decrease in Alliant Energy’s and IPL’s tax-related regulatory assets in the third quarter of 2022.

Commodity cost recovery - The cost recovery mechanism for WPL’s retail electric customers is based on forecasts of certain fuel-related costs expected to be incurred during forward-looking test periods and fuel monitoring ranges determined by the PSCW during each retail electric rate proceeding or in a separate fuel cost plan approval proceeding. During the nine months ended September 30, 2022, WPL’s actual fuel-related costs fell outside these fuel monitoring ranges, resulting in a $83 million deferral of higher than expected fuel-related costs as of September 30, 2022.

Derivatives - Refer to Note 11 for discussion of changes in Alliant Energy’s, IPL’s and WPL’s derivative liabilities/assets during the nine months ended September 30, 2022, which result in comparable changes to regulatory assets/liabilities on the balance sheets.

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]

Public Utilities, General Disclosures [Line Items]

Regulatory Matters

REGULATORY MATTERS

Regulatory Assets and Regulatory Liabilities -

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

Tax-related - Refer to Note 9 for discussion of Iowa Tax Reform, which resulted in a decrease in Alliant Energy’s and IPL’s tax-related regulatory assets in the third quarter of 2022.

Commodity cost recovery - The cost recovery mechanism for WPL’s retail electric customers is based on forecasts of certain fuel-related costs expected to be incurred during forward-looking test periods and fuel monitoring ranges determined by the PSCW during each retail electric rate proceeding or in a separate fuel cost plan approval proceeding. During the nine months ended September 30, 2022, WPL’s actual fuel-related costs fell outside these fuel monitoring ranges, resulting in a $83 million deferral of higher than expected fuel-related costs as of September 30, 2022.

Derivatives - Refer to Note 11 for discussion of changes in Alliant Energy’s, IPL’s and WPL’s derivative liabilities/assets during the nine months ended September 30, 2022, which result in comparable changes to regulatory assets/liabilities on the balance sheets.

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