Regulatory Matters (Tables)

12 Months Ended

Dec. 31, 2024

Schedule Of Regulatory Assets and Liabilities [Line Items]

Schedule of Regulatory Assets

Regulatory assets represent costs that are expected to be recovered in future regulated rates. The Company's regulatory assets reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):

	Weighted
	Average
	Remaining Life	2024		2023
Deferred net power costs	1 year	$	1,400	$	1,769
Asset retirement obligations	19 years	1,031		930
Deferred income taxes(1)	Various	455		435
Employee benefit plans(2)	13 years	386		414
Demand side management	9 years	281		245
Wildfire mitigation and vegetation management costs	Various	208		114
Levelized depreciation	28 years	185		167
Unrealized losses on regulated derivative contracts	1 year	182		173
Environmental costs	29 years	145		139
Asset disposition costs	Various	140		135
Cost of removal	26 years	122		143
Other	Various	814		901
Total regulatory assets		$	5,349	$	5,565
Reflected as:
Current assets		$	1,136	$	1,398
Noncurrent assets		4,213		4,167
Total regulatory assets		$	5,349	$	5,565

(1)Amounts primarily represent income tax benefits related to certain property-related basis differences and other various differences that were previously passed on to customers and will be included in regulated rates when the temporary differences reverse.

(2)Includes amounts not yet recognized as a component of net periodic benefit cost that are expected to be included in regulated rates when recognized.

Schedule of Regulatory Liabilities

The Company's regulatory liabilities reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):

	Weighted
	Average
	Remaining Life	2024		2023
Cost of removal(1)	27 years	$	2,918	$	2,741
Deferred income taxes(2)	Various	2,493		2,733
Asset retirement obligations	29 years	446		364
Employee benefit plans(3)	Various	292		211
Revenue sharing mechanisms	Various	263		243
Levelized depreciation	27 years	215		230
Other	Various	406		296
Total regulatory liabilities		$	7,033	$	6,818
Reflected as:
Current liabilities		$	279	$	174
Noncurrent liabilities		6,754		6,644
Total regulatory liabilities		$	7,033	$	6,818

(1)Amounts represent estimated costs, as accrued through depreciation rates and exclusive of ARO liabilities, of removing regulated property, plant and equipment in accordance with accepted regulatory practices. Amounts are deducted from rate base or otherwise accrue a carrying cost.

(2)Amounts primarily represent income tax liabilities related to the federal tax rate change from 35% to 21% that are probable to be passed on to customers, offset by income tax benefits related to certain property-related basis differences and other various differences that were previously passed on to customers and will be included in regulated rates when the temporary differences reverse.

(3)Includes amounts not yet recognized as a component of net periodic benefit cost that are expected to be returned to customers in future periods when recognized.

PAC

Schedule Of Regulatory Assets and Liabilities [Line Items]

Schedule of Regulatory Assets

Regulatory assets represent costs that are expected to be recovered in future rates. PacifiCorp's regulatory assets reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):

	Weighted
	Average
	Remaining
	Life	2024		2023
Employee benefit plans(1)	15 years	$	265	$	279
Utah mine disposition(2)	Various	83		79
Deferred net power costs	1 year	1,290		1,117
Unrealized loss on regulated derivative contracts	1 year	97		76
Environmental costs	29 years	145		139
Asset retirement obligation	29 years	393		300
Demand side management (DSM)	10 years	265		245
Wildfire mitigation and vegetation management costs	Various	104		114
Other	Various	275		224
Total regulatory assets		$	2,917	$	2,573
Reflected as:
Current assets		$	891	$	631
Noncurrent assets		2,026		1,942
Total regulatory assets		$	2,917	$	2,573

(1)Represents amounts not yet recognized as a component of net periodic benefit cost that are expected to be included in rates when recognized.

(2)Amounts represent regulatory assets established as a result of the Utah mine disposition in 2015 for the United Mine Workers of America ("UMWA") 1974 Pension Plan withdrawal and closure costs incurred to date considered probable of recovery. Refer to Note 10 for additional information.

Schedule of Regulatory Liabilities

Regulatory liabilities represent income to be recognized or amounts to be returned to customers in future periods. PacifiCorp's regulatory liabilities reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):

	Weighted
	Average
	Remaining
	Life	2024		2023
Cost of removal(1)	26 years	$	1,560	$	1,456
Deferred income taxes(2)	Various	861		1,006
Other	Various	221		148
Total regulatory liabilities		$	2,642	$	2,610
Reflected as:
Current liabilities		$	92	$	70
Noncurrent liabilities		2,550		2,540
Total regulatory liabilities		$	2,642	$	2,610

(1)Amounts represent estimated costs, as generally accrued through depreciation rates, of removing property, plant and equipment in accordance with accepted regulatory practices. Amounts are deducted from rate base or otherwise accrue a carrying cost.

(2)Amounts primarily represent income tax liabilities related to the federal tax rate change from 35% to 21% that are probable of being passed on to customers, partially offset by income tax benefits related to certain property-related basis differences and other various differences that were previously passed on to customers and will be included in regulated rates when the temporary differences reverse.

MEC

Schedule Of Regulatory Assets and Liabilities [Line Items]

Schedule of Regulatory Assets

Regulatory assets represent costs that are expected to be recovered in future regulated rates. MidAmerican Energy's regulatory assets reflected on the Balance Sheets consist of the following as of December 31 (in millions):

	Weighted
	Average
	Remaining Life	2024		2023
Asset retirement obligations(1)	14 years	$	546	$	541
Employee benefit plans(2)	9 years	17		16
Demand side management	1 year	16		—
Unrealized loss on regulated derivative contracts	1 year	13		11
Other	Various	30		32
Total		$	622	$	600

(1)Amount predominantly relates to AROs for fossil-fueled and wind-powered generating facilities. Refer to Note 11 for a discussion of AROs.

(2)Represents amounts not yet recognized as a component of net periodic benefit cost that are expected to be included in regulated rates when recognized.

Schedule of Regulatory Liabilities

Regulatory liabilities represent amounts expected to be returned to customers in future periods. MidAmerican Energy's regulatory liabilities reflected on the Balance Sheets consist of the following as of December 31 (in millions):

	Weighted
	Average
	Remaining Life	2024		2023
Cost of removal(1)	28 years	$	452	$	411
Asset retirement obligations(2)	29 years	443		360
Iowa electric revenue sharing(3)	Various	186		127
Employee benefit plans(4)	N/A	73		16
Deferred income taxes(5)	Various	47		102
Pre-funded AFUDC on transmission MVPs(6)	55 years	33		32
Other	Various	30		31
Total		$	1,264	$	1,079

(1)Amounts represent estimated costs, as accrued through depreciation rates and exclusive of ARO liabilities, of removing utility plant in accordance with accepted regulatory practices. Amounts are deducted from rate base or otherwise accrue a carrying cost.

(2)Amount represents the excess of nuclear decommission trust assets over the related ARO. Refer to Note 11 for a discussion of AROs.

(3)Represents accruals associated with a regulatory arrangement in Iowa in which equity returns exceeding specified thresholds reduce utility plant and retail electric energy cost recoveries as required.

(4)Represents amounts not yet recognized as a component of net periodic benefit cost that are to be returned to customers in future periods when recognized.

(5)Amounts primarily represent income tax liabilities primarily related to the federal tax rate change from 35% to 21% that are probable to be passed on to customers, offset by income tax benefits related to state accelerated tax depreciation and certain property-related basis differences that were previously passed on to customers and will be included in regulated rates when the temporary differences reverse.

(6)Represents AFUDC accrued on transmission MVPs that is deducted from rate base as a result of the inclusion of related construction work-in-progress in rate base.

NPC

Schedule Of Regulatory Assets and Liabilities [Line Items]

Schedule of Regulatory Assets

Regulatory assets represent costs that are expected to be recovered in future rates. Nevada Power's regulatory assets reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):

	Weighted
	Average
	Remaining Life	2024		2023
Deferred energy costs	1 year	$	110	$	575
Merger costs from 1999 merger	20 years	95		100
Asset retirement obligations	7 years	66		69
Unrealized loss on regulated derivative contracts	1 year	57		68
Decommissioning costs	3 years	57		56
Deferred operating costs	18 years	39		41
ON Line deferrals	28 years	38		40
Legacy meters	8 years	30		34
Other	Various	91		102
Total regulatory assets		$	583	$	1,085
Reflected as:
Current assets		$	124	$	586
Noncurrent assets		459		499
Total regulatory assets		$	583	$	1,085

Schedule of Regulatory Liabilities

Regulatory liabilities represent amounts that are expected to be returned to customers in future periods. Nevada Power's regulatory liabilities reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):

	Weighted
	Average
	Remaining Life	2024		2023
Deferred income taxes(1)	Various	$	510	$	525
Cost of removal(2)	37 years	399		368
Earning sharing mechanism	4 years	77		115
Other	Various	52		52
Total regulatory liabilities		$	1,038	$	1,060
Reflected as:
Current liabilities		$	41	$	43
Noncurrent liabilities		997		1,017
Total regulatory liabilities		$	1,038	$	1,060

(1)Amounts primarily represent income tax liabilities related to the federal tax rate change from 35% to 21% that are probable to be passed on to customers, offset by income tax benefits related to accelerated tax depreciation and certain property-related basis differences that were previously passed on to customers and will be included in regulated rates when the temporary differences reverse.

(2)Amounts represent estimated costs, as accrued through depreciation rates and exclusive of ARO liabilities, of removing regulated property, plant and equipment in accordance with accepted regulatory practices.

SPPC

Schedule Of Regulatory Assets and Liabilities [Line Items]

Schedule of Regulatory Assets

Regulatory assets represent costs that are expected to be recovered in future rates. Sierra Pacific's regulatory assets reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):

	Weighted
	Average
	Remaining Life	2024		2023
Natural disaster protection plan	1 year	$	90	$	78
Deferred energy costs	N/A	—		77
Merger costs from 1999 merger	22 years	57		60
Employee benefit plans (1)	7 years	45		48
Deferred operating costs	4 years	16		25
Other	Various	84		93
Total regulatory assets		$	292	$	381
Reflected as:
Current assets		$	90	$	161
Noncurrent assets		202		220
Total regulatory assets		$	292	$	381

(1)Represents amounts not yet recognized as a component of net periodic benefit cost that are expected to be included in regulated rates when recognized.

Schedule of Regulatory Liabilities

Regulatory liabilities represent amounts that are expected to be returned to customers in future periods. Sierra Pacific's regulatory liabilities reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):

	Weighted
	Average
	Remaining Life	2024		2023
Deferred income taxes(1)	Various	$	193	$	206
Cost of removal(2)	31 years	216		211
Deferred energy costs	1 year	86		—
Other	Various	27		22
Total regulatory liabilities		$	522	$	439
Reflected as:
Current liabilities		$	106	$	15
Noncurrent liabilities		416		424
Total regulatory liabilities		$	522	$	439

(1)Amounts primarily represent income tax liabilities related to the federal tax rate change from 35% to 21% that are probable to be passed on to customers, offset by income tax benefits related to accelerated tax depreciation and certain property-related basis differences and other various differences that were previously passed on to customers and will be included in regulated rates when the temporary differences reverse.

(2)Amounts represent estimated costs, as accrued through depreciation rates and exclusive of ARO liabilities, of removing regulated property, plant and equipment in accordance with accepted regulatory practices.

EEGH

Schedule Of Regulatory Assets and Liabilities [Line Items]

Schedule of Regulatory Assets

Eastern Energy Gas' regulatory assets reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):

	Weighted Average Remaining Life	2024		2023
Employee benefit plans(1)	10 years	$	24	$	33
Other	Various	17		21
Total regulatory assets		$	41	$	54
Reflected as:
Other current assets		$	11	$	9
Other assets		30		45
Total regulatory assets		$	41	$	54

(1)Represents costs expected to be recovered through future rates generally over the expected remaining service period of plan participants by certain rate-regulated subsidiaries.

Schedule of Regulatory Liabilities

Eastern Energy Gas' regulatory liabilities reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):

	Weighted Average Remaining Life	2024		2023
Deferred income taxes(1)	Various	$	416	$	425
Other postretirement benefit costs(2)	Various	129		124
Cost of removal(3)	48 years	92		85
Other	Various	19		22
Total regulatory liabilities		$	656	$	656
Reflected as:
Current liabilities		$	29	$	33
Noncurrent liabilities		627		623
Total regulatory liabilities		$	656	$	656

(1)Amounts primarily represent income tax liabilities related to the federal tax rate change from 35% to 21% that are probable to be passed on to customers, offset by income tax benefits related to certain property-related basis differences and other various differences that were previously passed on to customers and will be included in regulated rates when the temporary differences reverse.

(2)Reflects a regulatory liability for the collection of postretirement benefit costs allowed in rates in excess of expense incurred.

(3)Amounts represent estimated costs, as accrued through depreciation rates and exclusive of ARO liabilities, of removing regulated property, plant and equipment in accordance with accepted regulatory practices. Refer to Note 11 for more information.

EGTS

Schedule Of Regulatory Assets and Liabilities [Line Items]

Schedule of Regulatory Assets

Regulatory assets represent costs that are expected to be recovered in future regulated rates. EGTS' regulatory assets reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):

	Weighted Average Remaining Life	2024		2023
Employee benefit plans(1)	10 years	$	23	$	32
Other	Various	8		4
Total regulatory assets		$	31	$	36
Reflected as:
Other current assets		$	7	$	3
Other assets		24		33
Total regulatory assets		$	31	$	36

(1)Represents costs expected to be recovered through future rates generally over the expected remaining service period of plan participants.

Schedule of Regulatory Liabilities

Regulatory liabilities represent income to be recognized or amounts expected to be returned to customers in future periods. EGTS' regulatory liabilities reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):

	Weighted Average Remaining Life	2024		2023
Deferred income taxes(1)	Various	$	371	$	377
Other postretirement benefit costs(2)	Various	129		124
Cost of removal(3)	48 years	34		28
Other	Various	6		16
Total regulatory liabilities		$	540	$	545
Reflected as:
Current liabilities		$	13	$	22
Noncurrent liabilities		527		523
Total regulatory liabilities		$	540	$	545

(1)Amounts primarily represent income tax liabilities related to the federal tax rate change from 35% to 21% that are probable to be passed on to customers, offset by income tax benefits related to certain property-related basis differences and other various differences that were previously passed on to customers and will be included in regulated rates when the temporary differences reverse.

(2)Reflects a regulatory liability for the collection of postretirement benefit costs allowed in rates in excess of expense incurred.

(3)Amounts represent estimated costs, as accrued through depreciation rates and exclusive of ARO liabilities, of removing regulated property, plant and equipment in accordance with accepted regulatory practices. Refer to Note 11 for more information.