PROPERTY, PLANT, AND EQUIPMENT

12 Months Ended

Dec. 31, 2024

Property, Plant and Equipment [Abstract]

PROPERTY, PLANT, AND EQUIPMENT

PROPERTY, PLANT AND EQUIPMENT

The disclosures in this note apply to all Registrants unless indicated otherwise.

Property, Plant and Equipment is shown functionally on the face of the balance sheets. The following tables include the total plant balances as of December 31, 2024 and 2023:

December 31, 2024	AEP			AEP Texas		AEPTCo		APCo		I&M		OPCo		PSO		SWEPCo
	(in millions)
Regulated Property, Plant and Equipment
Generation	$	24,694.5	(a)	$	—	$	—	$	7,272.6	$	5,438.5	$	—	$	2,772.4	$	5,287.5	(a)
Transmission	38,871.9			7,546.2		14,913.4		5,001.5		1,957.8		3,663.9		1,345.3		2,863.8
Distribution	31,061.9			6,250.5		—		5,568.5		3,535.0		7,244.0		3,698.8		3,007.1
Other	6,544.9			1,172.9		515.9		1,023.9		948.3		1,245.3		546.8		682.7
CWIP	6,321.5		(a)	1,118.0		1,965.4		742.6		330.1		691.1		378.8		627.3		(a)
Less: Accumulated Depreciation	25,794.0			2,045.7		1,578.5		6,030.9		4,607.0		2,883.0		2,214.7		3,048.5
Total Regulated Property, Plant and Equipment - Net	81,700.7			14,041.9		15,816.2		13,578.2		7,602.7		9,961.3		6,527.4		9,419.9
Nonregulated Property, Plant and Equipment - Net	714.9			1.6		0.3		34.3		76.6		9.8		4.9		26.2
Total Property, Plant and Equipment - Net	$	82,415.6		$	14,043.5	$	15,816.5	$	13,612.5	$	7,679.3	$	9,971.1	$	6,532.3	$	9,446.1

December 31, 2023	AEP			AEP Texas		AEPTCo		APCo		I&M		OPCo		PSO		SWEPCo
	(in millions)
Regulated Property, Plant and Equipment
Generation	$	23,862.7	(a)	$	—	$	—	$	7,041.3	$	5,588.7	$	—	$	2,695.5	$	4,790.7	(a)
Transmission	35,903.6			6,812.6		13,723.9		4,711.8		1,906.4		3,395.1		1,228.3		2,660.6
Distribution	28,989.9			5,798.8		—		5,176.6		3,254.0		6,839.4		3,450.8		2,824.1
Other	5,986.1			1,142.9		501.2		943.7		856.8		1,114.4		502.7		544.1
CWIP	5,480.6		(a)	904.6		1,563.7		709.2		294.1		654.0		313.7		555.8		(a)
Less: Accumulated Depreciation	24,093.8			1,886.7		1,291.4		5,684.0		4,353.7		2,712.7		2,083.6		2,840.8
Total Regulated Property, Plant and Equipment - Net	76,129.1			12,772.2		14,497.4		12,898.6		7,546.3		9,290.2		6,107.4		8,534.5
Nonregulated Property, Plant and Equipment - Net	564.3			1.8		0.3		32.9		82.7		9.7		4.9		23.9
Total Property, Plant and Equipment - Net	$	76,693.4		$	12,774.0	$	14,497.7	$	12,931.5	$	7,629.0	$	9,299.9	$	6,112.3	$	8,558.4

(a)AEP and SWEPCo’s regulated generation and regulated CWIP include amounts related to SWEPCo’s Arkansas jurisdictional share of the Turk Plant.

Depreciation, Depletion and Amortization

The Registrants provide for depreciation of Property, Plant and Equipment, excluding coal-mining properties, on a straight-line basis over the estimated useful lives of property, generally using composite rates by functional class.  The following tables provide total regulated annual composite depreciation rates and depreciable lives for the Registrants:

AEP
	2024						2023						2022
Functional Class of Property	Annual Composite Depreciation Rate Ranges			Depreciable Life Ranges			Annual Composite Depreciation Rate Ranges			Depreciable Life Ranges			Annual Composite Depreciation Rate Ranges			Depreciable Life Ranges
				(in years)						(in years)						(in years)
Generation	2.7%	-	4.9%	20	-	162	2.7%	-	4.7%	20	-	162	2.7%	-	7.6%	20	-	132
Transmission	2.1%	-	2.7%	15	-	79	2.0%	-	2.7%	15	-	78	2.0%	-	2.7%	24	-	75
Distribution	2.8%	-	3.5%	7	-	85	2.9%	-	3.6%	7	-	85	2.7%	-	3.6%	7	-	78
Other	3.0%	-	8.9%	5	-	75	3.8%	-	9.1%	5	-	75	3.1%	-	14.4%	5	-	75

AEP Texas
	2024				2023				2022
Functional Class of Property	Annual Composite Depreciation Rate	Depreciable Life Ranges			Annual Composite Depreciation Rate	Depreciable Life Ranges			Annual Composite Depreciation Rate	Depreciable Life Ranges
		(in years)				(in years)				(in years)
Transmission	2.2%	50	-	79	2.2%	50	-	75	2.2%	50	-	75
Distribution	2.8%	15	-	74	2.9%	7	-	70	2.9%	7	-	70
Other	5.9%	5	-	54	6.0%	5	-	50	6.2%	5	-	50

AEPTCo
	2024				2023				2022
Functional Class of Property	Annual Composite Depreciation Rate	Depreciable Life Ranges			Annual Composite Depreciation Rate	Depreciable Life Ranges			Annual Composite Depreciation Rate	Depreciable Life Ranges
		(in years)				(in years)				(in years)
Transmission	2.7%	24	-	78	2.6%	24	-	78	2.6%	24	-	75
Other	7.1%	5	-	58	7.0%	5	-	58	6.6%	5	-	56

APCo
	2024				2023				2022
Functional Class of Property	Annual Composite Depreciation Rate	Depreciable Life Ranges			Annual Composite Depreciation Rate	Depreciable Life Ranges			Annual Composite Depreciation Rate	Depreciable Life Ranges
		(in years)				(in years)				(in years)
Generation	3.2%	35	-	162	3.3%	35	-	162	3.6%	35	-	118
Transmission	2.3%	15	-	78	2.3%	15	-	78	2.2%	24	-	75
Distribution	3.5%	12	-	60	3.6%	12	-	60	3.6%	12	-	57
Other	6.8%	5	-	55	7.4%	5	-	55	7.3%	5	-	55

I&M
	2024				2023				2022
Functional Class of Property	Annual Composite Depreciation Rate	Depreciable Life Ranges			Annual Composite Depreciation Rate	Depreciable Life Ranges			Annual Composite Depreciation Rate	Depreciable Life Ranges
		(in years)				(in years)				(in years)
Generation	4.9%	20	-	132	4.7%	20	-	132	4.9%	20	-	132
Transmission	2.6%	44	-	67	2.5%	44	-	67	2.5%	44	-	67
Distribution	2.8%	15	-	76	2.9%	14	-	71	3.1%	14	-	71
Other	8.9%	5	-	45	9.1%	5	-	45	10.1%	5	-	45

OPCo
	2024				2023				2022
Functional Class of Property	Annual Composite Depreciation Rate	Depreciable Life Ranges			Annual Composite Depreciation Rate	Depreciable Life Ranges			Annual Composite Depreciation Rate	Depreciable Life Ranges
		(in years)				(in years)				(in years)
Transmission	2.3%	39	-	60	2.3%	39	-	60	2.3%	39	-	60
Distribution	3.1%	11	-	70	3.1%	11	-	70	2.7%	11	-	70
Other	5.9%	5	-	50	6.4%	5	-	50	6.1%	5	-	50

PSO
	2024				2023				2022
Functional Class of Property	Annual Composite Depreciation Rate	Depreciable Life Ranges			Annual Composite Depreciation Rate	Depreciable Life Ranges			Annual Composite Depreciation Rate	Depreciable Life Ranges
		(in years)				(in years)				(in years)
Generation	3.3%	30	-	78	3.0%	25	-	75	3.1%	30	-	75
Transmission	2.6%	41	-	75	2.6%	41	-	75	2.5%	42	-	75
Distribution	2.8%	15	-	85	2.9%	15	-	85	2.9%	15	-	78
Other	6.6%	5	-	58	6.8%	5	-	58	6.8%	5	-	56

SWEPCo
	2024				2023				2022
Functional Class of Property	Annual Composite Depreciation Rate	Depreciable Life Ranges			Annual Composite Depreciation Rate	Depreciable Life Ranges			Annual Composite Depreciation Rate	Depreciable Life Ranges
		(in years)				(in years)				(in years)
Generation	3.7%	30	-	65	2.9%	30	-	65	2.7%	30	-	65
Transmission	2.2%	46	-	70	2.2%	46	-	70	2.3%	44	-	70
Distribution	2.9%	7	-	75	2.9%	7	-	75	2.9%	15	-	75
Other	6.7%	5	-	58	8.5%	5	-	58	9.0%	5	-	57

The following table includes the nonregulated annual composite depreciation rate ranges and nonregulated depreciable life ranges for AEP. With the exception of I&M, the Registrants' depreciation rate ranges and depreciable life ranges are not meaningful for nonregulated property for 2024, 2023 and 2022.

	2024						2023						2022
Functional Class of Property	Annual Composite Depreciation Rate Ranges (a)			Depreciable Life Ranges (a)			Annual Composite Depreciation Rate Ranges			Depreciable Life Ranges			Annual Composite Depreciation Rate Ranges			Depreciable Life Ranges
				(in years)						(in years)						(in years)
Generation	1.8%	-	6.0%	39	-	61	4.8%	-	6.7%	10	-	61	3.8%	-	8.7%	3	-	61
Transmission	NA			NA			2.5%			62			2.8%			10	-	62
Distribution	NA			NA			NA			NA			NA			NA
Other	9.7%			5	-	35	10.6%			5	-	35	25.2%			5	-	35

(a) I&M's annual composite depreciation rate for Generation property is 1.8% and the depreciable life is 39 years.

NA Not applicable.

For regulated operations, the composite depreciation rate generally includes a component for non-ARO removal costs, which is credited to Accumulated Depreciation and Amortization on the balance sheets.  Actual removal costs incurred are charged to Accumulated Depreciation and Amortization.  Any excess of accrued non-ARO removal costs over actual removal costs incurred is reclassified from Accumulated Depreciation and Amortization and reflected as a regulatory liability.  For nonregulated operations, non-ARO removal costs are expensed as incurred. 

Asset Retirement Obligations (Applies to all Registrants except AEPTCo)

Listed below are significant changes to the Registrants ARO balances as of December 31, 2024 and 2023:

•In April 2024, the Federal EPA finalized revisions to the CCR Rule to expand the scope of the rule to include inactive impoundments at inactive facilities as well as to establish requirements for currently exempt solid waste management units that involve the direct placement of CCR on the land. In the second quarter of 2024, AEP evaluated the applicability of the rule to current and former plant sites and incurred ARO liabilities of $602 million and revised cash flow estimates by an additional $72 million based on initial cost estimates. See the “Federal EPA’s Revised CCR Rule” section of Note 6 for additional information.

•In December 2024, I&M recorded a $176 million revision as a result of the completion of the latest Cook Plant nuclear decommissioning study.  I&M's ARO related to nuclear decommissioning costs for the Cook Plant was $1.97 billion and $2.11 billion as of December 31, 2024 and 2023. As of December 31, 2024 and 2023, the fair value of I&M’s assets that are legally restricted for purposes of settling decommissioning liabilities totaled $4.03 billion and $3.51 billion, respectively.  These assets are included in Spent Nuclear Fuel and Decommissioning Trusts on I&M’s balance sheets.

The following is a reconciliation of the 2024 and 2023 aggregate carrying amounts of ARO by Registrant:

Company	ARO as of December 31, 2023		Accretion Expense		Liabilities Incurred		Liabilities Settled		Revisions in Cash Flow Estimates (a)		ARO as of December 31, 2024
	(in millions)
AEP(b)(c)(d)(e)(f)	$	3,031.2	$	140.1	$	612.4	$	(102.4)	$	(69.6)	$	3,611.7
AEP Texas (e)	4.5		0.2		—		(0.8)		—		3.9
APCo (b)(e)(f)	464.0		27.7		247.1		(18.1)		81.0		801.7
I&M (b)(c)(e)	2,106.0		80.2		85.7		(2.2)		(175.9)		2,093.8
OPCo (b)(e)	2.1		1.4		52.9		(0.1)		—		56.3
PSO (b)(e)(f)	84.2		5.8		33.7		(1.9)		—		121.8
SWEPCo (b)(d)(e)(f)	281.6		16.2		30.2		(69.2)		19.9		278.7

Company	ARO as of December 31, 2022		Accretion Expense		Liabilities Incurred		Liabilities Settled		Revisions in Cash Flow Estimates (a)		ARO as of December 31, 2023
	(in millions)
AEP (b)(c)(d)(e)(f)	$	2,943.6	$	116.3	$	38.9	$	(130.6)	$	63.0	$	3,031.2
AEP Texas (e)	4.5		0.2		—		(0.3)		0.1		4.5
APCo (b)(e)(f)	427.7		16.8		16.1		(23.1)		26.5		464.0
I&M (b)(c)(e)	2,028.1		74.8		4.8		(3.7)		2.0		2,106.0
OPCo (e)	5.0		0.2		—		(3.1)		—		2.1
PSO (b)(e)(f)	75.7		4.7		5.8		(1.2)		(0.8)		84.2
SWEPCo (b)(d)(e)(f)	280.9		13.7		7.5		(55.0)		34.5		281.6

(a)Unless discussed above, primarily related to ash ponds, landfills and mine reclamation, generally due to changes in estimated closure area, volumes and/or unit costs.

(b)Includes ARO related to ash disposal facilities.

(c)Includes ARO related to nuclear decommissioning costs for the Cook Plant.

(d)Includes ARO related to Sabine and DHLC.

(e)Includes ARO related to asbestos removal.

(f)Includes ARO related to renewables.

Allowance for Funds Used During Construction and Interest Capitalization

The Registrants’ amounts of Allowance for Equity Funds Used During Construction are summarized in the following table:

	Years Ended December 31,
Company	2024		2023		2022
	(in millions)
AEP	$	211.0	$	174.9	$	133.7
AEP Texas	45.9		28.4		19.7
AEPTCo	89.4		83.2		70.7
APCo	16.1		11.9		11.7
I&M	13.3		10.9		9.8
OPCo	23.4		17.1		13.9
PSO	7.4		8.4		1.5
SWEPCo	13.5		11.5		4.9

The Registrants’ amounts of allowance for borrowed funds used during construction, including capitalized interest, are summarized in the following table:

	Years Ended December 31,
Company	2024		2023		2022
	(in millions)
AEP	$	129.8	$	117.3	$	63.0
AEP Texas	30.7		23.4		11.5
AEPTCo	33.7		31.4		22.4
APCo	10.5		14.1		6.5
I&M	9.2		7.7		5.7
OPCo	12.8		14.0		6.7
PSO	9.7		5.2		2.7
SWEPCo	15.1		9.8		4.3

Jointly-owned Electric Facilities (Applies to AEP, I&M, PSO and SWEPCo)

The Registrants have electric facilities that are jointly-owned with affiliated and nonaffiliated companies.  Using its own financing, each participating company is obligated to pay its share of the costs of these jointly-owned facilities in the same proportion as its ownership interest.  Each Registrant’s proportionate share of the operating costs associated with these facilities is included in its statements of income and the investments and accumulated depreciation are reflected in its balance sheets under Property, Plant and Equipment as follows:

				Registrant’s Share as of December 31, 2024
	Fuel Type	Percent of Ownership		Utility Plant in Service		Construction Work in Progress		Accumulated Depreciation
				(in millions)
AEP
Flint Creek Generating Station, Unit 1 (a)	Coal	50.0	%	$	404.1	$	3.4	$	188.8
Turk Generating Plant (a)	Coal	73.3	%	1,517.0		1.2		350.2
Total				$	1,921.1	$	4.6	$	539.0
I&M
Rockport Generating Plant (b)(c)	Coal	50.0	%	$	1,345.0	$	10.9	$	1,181.8
PSO
North Central Wind Energy Facilities (d)(e)	Wind	45.5	%	$	912.3	$	1.0	$	77.6
SWEPCo
Flint Creek Generating Station, Unit 1 (a)	Coal	50.0	%	$	404.1	$	3.4	$	188.8
Turk Generating Plant (a)	Coal	73.3	%	1,517.0		1.2		350.2
North Central Wind Energy Facilities (d)(e)	Wind	54.5	%	1,093.5		1.2		98.1
Total				$	3,014.6	$	5.8	$	637.1

				Registrant’s Share as of December 31, 2023
	Fuel Type	Percent of Ownership		Utility Plant in Service		Construction Work in Progress		Accumulated Depreciation
				(in millions)
AEP
Flint Creek Generating Station, Unit 1 (a)	Coal	50.0	%	$	402.8	$	1.6	$	167.5
Turk Generating Plant (a)	Coal	73.3	%	1,504.0		10.1		323.3
Total				$	1,906.8	$	11.7	$	490.8
I&M
Rockport Generating Plant (b)(c)	Coal	50.0	%	$	1,341.4	$	7.9	$	1,018.9
PSO
North Central Wind Energy Facilities (d)(e)	Wind	45.5	%	$	906.3	$	2.4	$	54.1
SWEPCo
Flint Creek Generating Station, Unit 1 (a)	Coal	50.0	%	$	402.8	$	1.6	$	167.5
Turk Generating Plant (a)	Coal	73.3	%	1,504.0		10.1		323.3
North Central Wind Energy Facilities (d)(e)	Wind	54.5	%	1,086.3		2.9		67.9
Total				$	2,993.1	$	14.6	$	558.7

(a)Operated by SWEPCo.

(b)Operated by I&M.

(c)AEGCo owns 50%.

(d)Operated by PSO.

(e)PSO and SWEPCo own undivided interests of 45.5% and 54.5% of the NCWF, respectively.