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Regulatory Matters

3 Months Ended

Mar. 31, 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
			March 31, 2022						December 31, 2021						March 31, 2022						December 31, 2021						March 31, 2022						December 31, 2021
Tax-related			$949						$934						$896						$884						$53						$50
Pension and OPEB costs			453						462						224						228						229						234
Asset retirement obligations			134						128						94						89						40						39
Assets retired early			88						92						64						66						24						26
IPL’s DAEC PPA amendment			84						90						84						90						—						—
WPL’s Western Wisconsin gas distribution expansion investments			50						52						—						—						50						52
Commodity cost recovery			42						42						2						2						40						40
Other			119						140						68						84						51						56
			$1,919						$1,940						$1,432						$1,443						$487						$497

Regulatory liabilities were comprised of the following items (in millions):

			Alliant Energy												IPL												WPL
			March 31, 2022						December 31, 2021						March 31, 2022						December 31, 2021						March 31, 2022						December 31, 2021
Tax-related			$578						$585						$310						$312						$268						$273
Cost of removal obligations			391						384						256						252						135						132
Derivatives			258						166						125						77						133						89
Electric transmission cost recovery			50						51						29						27						21						24
WPL’s West Riverside liquidated damages			35						36						—						—						35						36
Other			60						49						34						23						26						26
			$1,372						$1,271						$754						$691						$618						$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
			March 31, 2022						December 31, 2021						March 31, 2022						December 31, 2021						March 31, 2022						December 31, 2021
Tax-related			$949						$934						$896						$884						$53						$50
Pension and OPEB costs			453						462						224						228						229						234
Asset retirement obligations			134						128						94						89						40						39
Assets retired early			88						92						64						66						24						26
IPL’s DAEC PPA amendment			84						90						84						90						—						—
WPL’s Western Wisconsin gas distribution expansion investments			50						52						—						—						50						52
Commodity cost recovery			42						42						2						2						40						40
Other			119						140						68						84						51						56
			$1,919						$1,940						$1,432						$1,443						$487						$497

Regulatory liabilities were comprised of the following items (in millions):

			Alliant Energy												IPL												WPL
			March 31, 2022						December 31, 2021						March 31, 2022						December 31, 2021						March 31, 2022						December 31, 2021
Tax-related			$578						$585						$310						$312						$268						$273
Cost of removal obligations			391						384						256						252						135						132
Derivatives			258						166						125						77						133						89
Electric transmission cost recovery			50						51						29						27						21						24
WPL’s West Riverside liquidated damages			35						36						—						—						35						36
Other			60						49						34						23						26						26
			$1,372						$1,271						$754						$691						$618						$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
			March 31, 2022						December 31, 2021						March 31, 2022						December 31, 2021						March 31, 2022						December 31, 2021
Tax-related			$949						$934						$896						$884						$53						$50
Pension and OPEB costs			453						462						224						228						229						234
Asset retirement obligations			134						128						94						89						40						39
Assets retired early			88						92						64						66						24						26
IPL’s DAEC PPA amendment			84						90						84						90						—						—
WPL’s Western Wisconsin gas distribution expansion investments			50						52						—						—						50						52
Commodity cost recovery			42						42						2						2						40						40
Other			119						140						68						84						51						56
			$1,919						$1,940						$1,432						$1,443						$487						$497

Regulatory liabilities were comprised of the following items (in millions):

			Alliant Energy												IPL												WPL
			March 31, 2022						December 31, 2021						March 31, 2022						December 31, 2021						March 31, 2022						December 31, 2021
Tax-related			$578						$585						$310						$312						$268						$273
Cost of removal obligations			391						384						256						252						135						132
Derivatives			258						166						125						77						133						89
Electric transmission cost recovery			50						51						29						27						21						24
WPL’s West Riverside liquidated damages			35						36						—						—						35						36
Other			60						49						34						23						26						26
			$1,372						$1,271						$754						$691						$618						$580

X

- Definition

The entire disclosure for public utilities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-URI http://asc.fasb.org/topic&trid=2156578

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