Property, Plant and Equipment (Tables)

9 Months Ended

Sep. 30, 2024

Asset Retirement Obligation (ARO)

Company	ARO as of December 31, 2023		Accretion Expense		Liabilities Incurred		Liabilities Settled		Revisions in Cash Flow Estimates (a)		ARO as of September 30, 2024
	(in millions)
AEP(b)(c)(d)(e)(f)(g)	$	3,031.2	$	97.2	$	606.0	$	(80.3)	$	122.9	$	3,777.0
AEP Texas (b)(e)	4.5		0.2		—		(0.8)		—		3.9
APCo (b)(e)	464.0		17.6		247.1		(14.2)		97.2		811.7
I&M (b)(c)(e)	2,106.0		59.1		85.7		(1.9)		—		2,248.9
OPCo (b)(e)	2.1		0.6		52.9		(0.1)		—		55.5
PSO (b)(e)(g)	84.2		4.1		33.7		(1.1)		—		120.9
SWEPCo (b)(d)(e)(g)	281.6		10.8		23.8		(54.2)		19.9		281.9

(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 of $2.1 billion and $2.1 billion as of September 30, 2024 and December 31, 2023, respectively.

(d)Includes ARO related to Sabine and DHLC.

(e)Includes ARO related to asbestos removal.

(f)Includes ARO related to solar farms.

(g)Includes ARO related to wind farms.