Effects of Regulation

12 Months Ended

Dec. 31, 2023

Effects of Regulation

EFFECTS OF REGULATION

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

Coal-Fired Generation Plants (Applies to AEP, PSO and SWEPCo)

Compliance with extensive environmental regulations requires significant capital investment in environmental monitoring, installation of pollution control equipment, emission fees, disposal costs and permits. Management continuously evaluates cost estimates of complying with these regulations which has resulted in, and in the future may result in, a decision to retire coal-fired generating facilities earlier than their currently estimated useful lives.

Management is seeking or will seek regulatory recovery, as necessary, for any net book value remaining when the plants are retired. To the extent the net book value of these generation assets is not deemed recoverable, it could materially reduce future net income and cash flows and impact financial condition.

Regulated Generating Units that have been Retired

SWEPCo

In December 2021, the Dolet Hills Power Station was retired. As part of the 2020 Texas Base Rate Case, the PUCT authorized recovery of SWEPCo’s Texas jurisdictional share of the Dolet Hills Power Station through 2046, but denied SWEPCo the ability to earn a return on this investment resulting in a disallowance of $12 million in 2021. As part of the 2021 Arkansas Base Rate Case, the APSC authorized recovery of SWEPCo’s Arkansas jurisdictional share of the Dolet Hills Power Station through 2027, but denied SWEPCo the ability to earn a return on this investment resulting in a disallowance of $2 million in the second quarter of 2022. Also, the APSC did not rule on the prudency of the early retirement of the Dolet Hills Power Station, which will be addressed in a future proceeding. As part of the 2020 Louisiana Base Rate Case, the LPSC authorized the recovery of SWEPCo’s Louisiana share of the Dolet Hills Power Station, through a separate rider, through 2032, but did not rule on the prudency of the early retirement of the plant, which is being addressed in a separate proceeding. See “2020 Texas Base Rate Case” and “2020 Louisiana Base Rate Case” sections of Note 4 for additional information.

In March 2023, the Pirkey Plant was retired. As part of the 2020 Louisiana Base Rate Case, the LPSC authorized the recovery of SWEPCo’s Louisiana jurisdictional share of the Pirkey Plant, through a separate rider, through 2032. As part of the 2021 Arkansas Base Rate Case, the APSC granted SWEPCo regulatory asset treatment. SWEPCo will request recovery including a weighted average cost of capital carrying charge through a future proceeding. In July 2023, Texas ALJs issued a proposal for decision that concluded the decision to retire the Pirkey Plant was prudent. In September 2023, the PUCT rejected the ALJs proposal for decision concluding the retirement of the Pirkey Plant was prudent. In the open meeting, the commissioners expressed their concerns that the analysis in support of SWEPCo’s decision to retire the Pirkey Plant was not robust enough and that SWEPCo should have re-evaluated the decision following Winter Storm Uri. The treatment of the cost of recovery of the Pirkey Plant is expected to be addressed in a future rate case. As of December 31, 2023, the Texas jurisdictional share of the net book value of the Pirkey Plant was $67 million. To the extent any portion of the Texas jurisdictional share of the net book value of the Pirkey Plant is not recoverable, it could reduce future net income and cash flows and impact financial condition.

Regulated Generating Units to be Retired

PSO

In 2014, PSO received final approval from the Federal EPA to close Northeastern Plant, Unit 3, in 2026. The plant was originally scheduled to close in 2040. As a result of the early retirement date, PSO revised the useful life of Northeastern Plant, Unit 3, to the projected retirement date of 2026 and the incremental depreciation is being deferred as a regulatory asset. As part of the 2022 Oklahoma Base Rate Case, PSO will continue to recover Northeastern Plant, Unit 3 through 2040.

SWEPCo

In November 2020, management announced that it will cease using coal at the Welsh Plant in 2028. As a result of the announcement, SWEPCo began recording a regulatory asset for accelerated depreciation.

The table below summarizes the net book value including CWIP, before cost of removal and materials and supplies, as of December 31, 2023, of generating facilities planned for early retirement:

Plant	Net Book Value		Accelerated Depreciation Regulatory Asset		Cost of Removal Regulatory Liability			Projected Retirement Date		Current Authorized Recovery Period	Annual Depreciation (a)
	(dollars in millions)
Northeastern Plant, Unit 3	$	104.5	$	164.2	$	20.5	(b)	2026		(c)	$	15.0
Welsh Plant, Units 1 and 3	352.0		125.6		58.2		(d)	2028	(e)	(f)	38.6

(a)Represents the amount of annual depreciation that has been collected from customers over the prior 12-month period.

(b)Includes Northeastern Plant, Unit 4, which was retired in 2016. Removal of Northeastern Plant, Unit 4, will be performed with the removal of Northeastern Plant, Unit 3, after retirement.

(c)Northeastern Plant, Unit 3 is currently being recovered through 2040.

(d)Includes Welsh Plant, Unit 2, which was retired in 2016. Removal of Welsh Plant, Unit 2, will be performed with the removal of Welsh Plant, Units 1 and 3, after retirement.

(e)Represents projected retirement date of coal assets, units are being evaluated for conversion to natural gas after 2028.

(f)Unit 1 is being recovered through 2027 in the Louisiana jurisdiction and through 2037 in the Arkansas and Texas jurisdictions. Unit 3 is being recovered through 2032 in the Louisiana jurisdiction and through 2042 in the Arkansas and Texas jurisdictions.

Dolet Hills Power Station and Related Fuel Operations (Applies to AEP and SWEPCo)

In December 2021, the Dolet Hills Power Station was retired. While in operation, DHLC provided 100% of the fuel supply to Dolet Hills Power Station. The remaining book value of Dolet Hills Power Station non-fuel related assets are recoverable by SWEPCo through rate riders. As of December 31, 2023, SWEPCo’s share of the net investment in the Dolet Hills Power Station was $103 million, including materials and supplies, net of cost of removal collected in rates. Fuel costs incurred by the Dolet Hills Power Station are recoverable by SWEPCo through active fuel clauses and are subject to prudency determinations by the various commissions. After closure of the DHLC mining operations and the Dolet Hills Power Station, additional reclamation and other land-related costs incurred by DHLC and Oxbow will continue to be billed to SWEPCo and included in existing fuel clauses. As of December 31, 2023, SWEPCo had a net under-recovered fuel balance of $77 million, inclusive of costs related to the Dolet Hills Power Station billed by DHLC, but excluding impacts of the February 2021 severe winter weather event.

In March 2021, the LPSC issued an order allowing SWEPCo to recover up to $20 million of fuel costs in 2021 and defer approximately $35 million of additional costs with a recovery period to be determined at a later date. In August 2022, the LPSC staff filed testimony recommending fuel disallowances of up to $55 million, including denial of recovery of the $35 million deferral, with refunds to customers over five years. In February 2024, an ALJ issued a final recommendation which included a proposed $55 million refund to customers and the denial of recovery of the $35 million deferral. SWEPCo filed a motion to present oral arguments with the LPSC to dispute the ALJ’s recommendations. Management believes its financial statements adequately address the impact of the LPSC staff and ALJ recommendations. A decision from the LPSC is expected in the first quarter of 2024.

In March 2021, the APSC approved fuel rates that provide recovery of $20 million for the Arkansas share of the 2021 Dolet Hills Power Station fuel costs over five years through the existing fuel clause.

In September 2023, the PUCT approved an unopposed settlement agreement that provides recovery of $48 million of Oxbow mine related costs through 2035.

If any of these costs are not recoverable or customer refunds are required, it could reduce future net income and cash flows and impact financial condition.

Pirkey Plant and Related Fuel Operations (Applies to AEP and SWEPCo)

In March 2023, the Pirkey Plant was retired. SWEPCo is recovering, or will seek recovery of, the remaining net book value of Pirkey Plant non-fuel costs. As of December 31, 2023, SWEPCo’s share of the net investment in the Pirkey Plant was $182 million, including materials and supplies, net of cost of removal. See the “Regulated Generating Units that have been Retired” section above for additional information. Fuel costs are recovered through active fuel clauses and are subject to prudency determinations by the various commissions. As of March 31, 2023, SWEPCo fuel deliveries, including billings of all fixed costs, from Sabine ceased. Additionally, as of December 31, 2023, SWEPCo had a net under-recovered fuel balance of $77 million, inclusive of costs related to the Pirkey Plant billed by Sabine, but excluding impacts of the February 2021 severe winter weather event. Remaining operational, reclamation and other land-related costs incurred by Sabine will be billed to SWEPCo and included in existing fuel clauses.

In July 2023, the LPSC ordered that a separate proceeding be established to review the prudence of the decision to retire the Pirkey Plant, including the costs included in fuel for years starting in 2019 and after. In September 2023, the PUCT approved an unopposed settlement agreement that provides recovery of $33 million of Sabine related fuel costs through 2035.

If any of these costs are not recoverable, it could reduce future net income and cash flows and impact financial condition.

Regulatory Assets and Liabilities

Regulatory assets and liabilities are comprised of the following items:

	AEP
	December 31,				Remaining Recovery Period
	2023		2022
Current Regulatory Assets	(in millions)
Under-recovered Fuel Costs - earns a return	$	357.4	$	625.7	1 year
Under-recovered Fuel Costs - does not earn a return	62.7		588.5		1 year
Unrecovered Winter Storm Fuel Costs - earns a return (a)	93.9		95.8		1 year
Total Current Regulatory Assets	$	514.0	$	1,310.0
Noncurrent Regulatory Assets
Regulatory assets pending final regulatory approval:
Regulatory Assets Currently Earning a Return
Welsh Plant, Units 1 and 3 Accelerated Depreciation	$	125.6	$	85.6
Pirkey Plant Accelerated Depreciation	114.4		116.5
Unrecovered Winter Storm Fuel Costs (a)	60.1		84.6
Other Regulatory Assets Pending Final Regulatory Approval	49.8		68.9
Total Regulatory Assets Currently Earning a Return	349.9		355.6
Regulatory Assets Currently Not Earning a Return
Storm-Related Costs	408.9		407.1
2020-2022 Virginia Triennial Under-Earnings	—		37.9
Other Regulatory Assets Pending Final Regulatory Approval	78.5		81.5
Total Regulatory Assets Currently Not Earning a Return	487.4		526.5
Total Regulatory Assets Pending Final Regulatory Approval	837.3		882.1
Regulatory assets approved for recovery:
Regulatory Assets Currently Earning a Return
Plant Retirement Costs - Unrecovered Plant (b)	664.2		689.9		23 years
Long-term Under-recovered Fuel Costs - West Virginia	291.5		—		11 years
Storm-Related Costs	170.9		8.4		5 years
Plant Retirement Costs - Asset Retirement Obligation Costs	110.8		110.6		19 years
Long-term Under-recovered Fuel Costs - Virginia	107.0		223.3		2 years
Unrecovered Winter Storm Fuel Costs (a)	99.3		148.6		4 years
Fuel Mine Closure Costs - Texas	74.3		—		12 years
Pirkey Plant Accelerated Depreciation - Louisiana	65.8		63.0		9 years
Rockport Plant Dry Sorbent Injection System and Selective Catalytic Reduction	46.9		56.6		5 years
Kentucky Deferred Purchased Power Expenses	43.5		53.0		4 years
Ohio Basic Transmission Cost Rider	42.2		14.3		2 years
Plant Retirement Costs - Unrecovered Plant, Dolet Hills Power Station, Louisiana	40.8		45.1		9 years
Texas Mobile Temporary Emergency Electric Energy Facilities Rider	33.4		—		2 years
Environmental Control Projects	31.4		33.9		17 years
Meter Replacement Costs	23.5		34.2		4 years
Long-term Under-recovered Fuel Costs - Oklahoma	—		252.7
Other Regulatory Assets Approved for Recovery	101.4		125.0		various
Total Regulatory Assets Currently Earning a Return	1,946.9		1,858.6
Regulatory Assets Currently Not Earning a Return
Pension and OPEB Funded Status	1,054.1		975.4		12 years
Plant Retirement Costs - Asset Retirement Obligation Costs	330.2		308.5		19 years
Unrealized Loss on Forward Commitments	131.4		40.1		9 years
Unamortized Loss on Reacquired Debt	97.2		104.1		25 years
Fuel and Purchased Power Adjustment Rider	68.3		76.3		2 years
Cook Plant Nuclear Refueling Outage Levelization	55.7		81.2		2 years
OVEC Purchased Power	50.1		—		2 years
Plant Retirement Costs - Unrecovered Plant, Texas	48.7		51.7		23 years
Storm-Related Costs	38.5		11.9		2 years
2020-2022 Virginia Triennial Under Earnings	37.4		—		4 years
Ohio Enhanced Service Reliability Plan	35.3		33.3		2 years
Ohio Distribution Investment Rider	35.3		2.3		2 years
Postemployment Benefits	30.6		32.1		3 years
Peak Demand Reduction/Energy Efficiency	23.9		41.7		3 years
Other Regulatory Assets Approved for Recovery	271.5		262.7		various
Total Regulatory Assets Currently Not Earning a Return	2,308.2		2,021.3
Total Regulatory Assets Approved for Recovery	4,255.1		3,879.9
Total Noncurrent Regulatory Assets	$	5,092.4	$	4,762.0

(a)See “February 2021 Severe Winter Weather Impacts in SPP” section of SWEPCo Rate Matters in Note 4 for additional information.

(b)Northeastern Plant, Unit 3 is approved for recovery through 2040, but expected to retire in 2026. PSO records a regulatory asset for accelerated depreciation. See “Regulated Generating Units to be Retired” section above for additional information.

	AEP
	December 31,				Remaining
	2023		2022		Refund Period
Current Regulatory Liabilities	(in millions)
Over-recovered Fuel Costs - pays a return	$	3.3	$	1.4	1 year
Over-recovered Fuel Costs - does not pay a return	23.2		—		1 year
Total Current Regulatory Liabilities	$	26.5	$	1.4
Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits
Regulatory liabilities pending final regulatory determination:
Regulatory Liabilities Currently Paying a Return
Income Taxes, Net (a)	$	103.1	$	149.7
Total Regulatory Liabilities Currently Paying a Return	103.1		149.7
Regulatory Liabilities Currently Not Paying a Return
FERC 2021 Transmission Formula Rate Challenge Refunds	103.1		—
Other Regulatory Liabilities Pending Final Regulatory Determination	1.7		4.1
Total Regulatory Liabilities Currently Not Paying a Return	104.8		4.1
Total Regulatory Liabilities Pending Final Regulatory Determination	207.9		153.8
Regulatory liabilities approved for payment:
Regulatory Liabilities Currently Paying a Return
Asset Removal Costs	3,563.5		3,392.4		(b)
Income Taxes, Net (a)	2,179.7		2,504.5		(c)
Rockport Plant, Unit 2 Accelerated Depreciation for Leasehold Improvements	44.9		53.8		5 years
Other Regulatory Liabilities Approved for Payment	35.0		32.7		various
Total Regulatory Liabilities Currently Paying a Return	5,823.1		5,983.4
Regulatory Liabilities Currently Not Paying a Return
Excess Nuclear Decommissioning Funding	1,721.9		1,318.5		(d)
Deferred Investment Tax Credits	154.5		237.3		31 years
Spent Nuclear Fuel	47.6		45.8		(d)
2017-2019 Virginia Triennial Revenue Provision	37.1		39.1		26 years
Demand Side Management	31.3		15.7		2 years
Over-recovered Fuel Costs - Ohio	26.1		32.2		9 years
PJM Transmission Enhancement Refund	22.8		34.1		2 years
PJM Costs and Off-system Sales Margin Sharing - Indiana	14.1		34.2		2 years
OVEC Purchased Power	—		47.1
Unrealized Gain on Forward Commitments	—		45.2
Other Regulatory Liabilities Approved for Payment	96.0		129.2		various
Total Regulatory Liabilities Currently Not Paying a Return	2,151.4		1,978.4
Total Regulatory Liabilities Approved for Payment	7,974.5		7,961.8
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits	$	8,182.4	$	8,115.6

(a)Predominately pays a return due to the inclusion of Excess ADIT in rate base.

(b)Relieved as removal costs are incurred.

(c)Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $228 million and $277 million for the years ended December 31, 2023 and 2022, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2023 is to be refunded over 5 years.

(d)Relieved when plant is decommissioned.

	AEP Texas
	December 31,				Remaining Recovery Period
Regulatory Assets:	2023		2022
	(in millions)
Noncurrent Regulatory Assets
Regulatory assets pending final regulatory approval:
Regulatory Assets Currently Earning a Return
Texas Mobile Generation Lease Payments	$	—	$	17.6
Total Regulatory Assets Currently Earning a Return	—		17.6
Regulatory Assets Currently Not Earning a Return
Storm-Related Costs	37.7		26.7
Line Inspection Costs	5.7		4.5
Vegetation Management Program	5.2		5.2
Texas Retail Electric Provider Bad Debt Expense	4.0		4.1
Other Regulatory Assets Pending Final Regulatory Approval	11.7		8.9
Total Regulatory Assets Currently Not Earning a Return	64.3		49.4
Total Regulatory Assets Pending Final Regulatory Approval	64.3		67.0
Regulatory assets approved for recovery:
Regulatory Assets Currently Earning a Return
Texas Mobile Temporary Emergency Electric Energy Facilities Rider	33.4		—		2 years
Meter Replacement Costs	9.4		16.1		2 years
Other Regulatory Assets Approved for Recovery	0.7		1.4		various
Total Regulatory Assets Currently Earning a Return	43.5		17.5
Regulatory Assets Currently Not Earning a Return
Pension and OPEB Funded Status	183.2		173.2		12 years
Peak Demand Reduction/Energy Efficiency	9.2		11.9		2 years
Vegetation Management Program	6.8		12.1		2 years
Storm-Related Costs	4.3		8.5		2 years
Other Regulatory Assets Approved for Recovery	4.0		8.1		various
Total Regulatory Assets Currently Not Earning a Return	207.5		213.8
Total Regulatory Assets Approved for Recovery	251.0		231.3
Total Noncurrent Regulatory Assets	$	315.3	$	298.3

	AEP Texas
	December 31,				Remaining Refund Period
Regulatory Liabilities:	2023		2022
	(in millions)
Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits
Regulatory liabilities pending final regulatory determination:
Regulatory Liabilities Currently Paying a Return
Income Taxes, Net (a)	$	13.0	$	13.0
Total Regulatory Liabilities Currently Paying a Return	13.0		13.0
Regulatory Liabilities Currently Not Paying a Return
Other Regulatory Liabilities Pending Final Regulatory Determination	1.5		1.8
Total Regulatory Liabilities Currently Not Paying a Return	1.5		1.8
Total Regulatory Liabilities Pending Final Regulatory Determination	14.5		14.8
Regulatory liabilities approved for payment:
Regulatory Liabilities Currently Paying a Return
Asset Removal Costs	797.1		766.8		(b)
Income Taxes, Net (a)	412.0		431.6		(c)
Other Regulatory Liabilities Approved for Payment	3.8		4.3		various
Total Regulatory Liabilities Currently Paying a Return	1,212.9		1,202.7
Regulatory Liabilities Currently Not Paying a Return
Transition and Restoration Charges	26.6		29.4		6 years
Other Regulatory Liabilities Approved for Payment	7.4		12.7		various
Total Regulatory Liabilities Currently Not Paying a Return	34.0		42.1
Total Regulatory Liabilities Approved for Payment	1,246.9		1,244.8
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits	$	1,261.4	$	1,259.6

(a)Predominately pays a return due to the inclusion of Excess ADIT in rate base.

(b)Relieved as removal costs are incurred.

(c)Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets.

	AEPTCo
	December 31,				Remaining Recovery Period
Regulatory Assets:	2023		2022
	(in millions)
Noncurrent Regulatory Assets
Regulatory assets approved for recovery:
Regulatory Assets Currently Not Earning a Return
PJM/SPP Annual Formula Rate True-up	$	3.1	$	7.2	2 years
Total Regulatory Assets Approved for Recovery	3.1		7.2
Total Noncurrent Regulatory Assets	$	3.1	$	7.2

	AEPTCo
	December 31,				Remaining Refund Period
Regulatory Liabilities:	2023		2022
	(in millions)
Noncurrent Regulatory Liabilities
Regulatory liabilities pending final regulatory determination:
Regulatory Liabilities Currently Paying a Return
Income Taxes, Net (a)	$	8.7	$	8.7
Total Regulatory Liabilities Pending Final Regulatory Determination	8.7		8.7
Regulatory liabilities approved for payment:
Regulatory Liabilities Currently Paying a Return
Asset Removal Costs	466.3		358.8		(b)
Income Taxes, Net (a)	308.7		355.8		(c)
Total Regulatory Liabilities Approved for Payment	775.0		714.6
Total Noncurrent Regulatory Liabilities	$	783.7	$	723.3

(a)Predominately pays a return due to the inclusion of Excess ADIT in rate base.

(b)Relieved as removal costs are incurred.

(c)Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $13 million and $16 million for the years ended December 31, 2023 and 2022, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2023 is to be refunded over 5 years.

	APCo
	December 31,				Remaining Recovery Period
Regulatory Assets:	2023		2022
	(in millions)
Current Regulatory Assets
Under-recovered Fuel Costs - earns a return	$	147.4	$	180.7	1 year
Under-recovered Fuel Costs - does not earn a return	8.0		292.4		1 year
Total Current Regulatory Assets	$	155.4	$	473.1
Noncurrent Regulatory Assets
Regulatory assets pending final regulatory approval:
Regulatory Assets Currently Earning a Return
Other Regulatory Assets Pending Final Regulatory Approval	$	0.6	$	7.0
Total Regulatory Assets Currently Earning a Return	0.6		7.0
Regulatory Assets Currently Not Earning a Return
Storm-Related Costs - West Virginia	91.5		72.6
Plant Retirement Costs - Asset Retirement Obligation Costs	25.9		25.9
2020-2022 Virginia Triennial Under-Earnings	—		37.9
Other Regulatory Assets Pending Final Regulatory Approval	7.5		1.1
Total Regulatory Assets Currently Not Earning a Return	124.9		137.5
Total Regulatory Assets Pending Final Regulatory Approval	125.5		144.5
Regulatory assets approved for recovery:
Regulatory Assets Currently Earning a Return
Long-term Under-recovered Fuel Costs - West Virginia	154.2		—		11 years
Long-term Under-recovered Fuel Costs - Virginia	107.0		223.3		2 years
Plant Retirement Costs - Unrecovered Plant	72.0		75.6		20 years
Other Regulatory Assets Approved for Recovery	7.1		0.4		various
Total Regulatory Assets Currently Earning a Return	340.3		299.3
Regulatory Assets Currently Not Earning a Return
Plant Retirement Costs - Asset Retirement Obligation Costs	324.7		303.1		15 years
Pension and OPEB Funded Status	115.8		108.3		12 years
Unamortized Loss on Reacquired Debt	70.7		74.4		22 years
2020-2022 Virginia Triennial Under-Earnings	37.4		—		4 years
Virginia Transmission Rate Adjustment Clause	25.5		18.7		2 years
Unrealized Loss on Forward Commitments	21.9		—		3 years
Peak Demand Reduction/Energy Efficiency	15.0		15.8		3 years
Postemployment Benefits	14.9		13.7		3 years
Vegetation Management Program - West Virginia	12.9		13.7		2 years
Excess SO2 Allowance Inventory - Virginia	11.8		—		9 years
Virginia Generation Rate Adjustment Clause	10.9		8.0		2 years
Virginia Clean Economy Act	8.0		16.7		2 years
2017-2019 Virginia Triennial Under-Earnings	2.3		30.1		1 year
Other Regulatory Assets Approved for Recovery	17.5		12.3		various
Total Regulatory Assets Currently Not Earning a Return	689.3		614.8
Total Regulatory Assets Approved for Recovery	1,029.6		914.1
Total Noncurrent Regulatory Assets	$	1,155.1	$	1,058.6

	APCo
	December 31,				Remaining Refund Period
Regulatory Liabilities:	2023		2022
	(in millions)
Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits
Regulatory liabilities pending final regulatory determination:
Regulatory Liabilities Currently Paying a Return
Income Taxes, Net (a)	$	7.9	$	30.5
Total Regulatory Liabilities Currently Paying a Return	7.9		30.5
Regulatory Liabilities Currently Not Paying a Return
FERC 2021 Transmission Formula Rate Challenge Refunds	19.7		—
Total Regulatory Liabilities Currently Not Paying a Return	19.7		—
Total Regulatory Liabilities Pending Final Regulatory Determination	27.6		30.5
Regulatory liabilities approved for payment:
Regulatory Liabilities Currently Paying a Return
Asset Removal Costs	759.6		713.5		(b)
Income Taxes, Net (a)	240.1		291.3		(c)
Deferred Investment Tax Credits	0.3		0.3		30 years
Total Regulatory Liabilities Currently Paying a Return	1,000.0		1,005.1
Regulatory Liabilities Currently Not Paying a Return
2017-2019 Virginia Triennial Revenue Provision	37.1		39.1		26 years
Over-recovered Deferred Wind Power Costs - Virginia	2.6		13.6		2 years
Unrealized Gain on Forward Commitments	—		34.5
Other Regulatory Liabilities Approved for Payment	14.6		20.8		various
Total Regulatory Liabilities Currently Not Paying a Return	54.3		108.0
Total Regulatory Liabilities Approved for Payment	1,054.3		1,113.1
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits	$	1,081.9	$	1,143.6

(a)Predominately pays a return due to the inclusion of Excess ADIT in rate base.

(b)Relieved as removal costs are incurred.

(c)Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $35 million and $19 million for the years ended December 31, 2023 and 2022, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2023 is to be refunded over 5 years.

	I&M
	December 31,				Remaining Recovery Period
Regulatory Assets:	2023		2022
	(in millions)
Current Regulatory Assets
Under-recovered Fuel Costs, Michigan - earns a return	$	14.8	$	9.0	1 year
Under-recovered Fuel Costs, Indiana - does not earn a return	—		38.1
Total Current Regulatory Assets	$	14.8	$	47.1
Noncurrent Regulatory Assets
Regulatory assets pending final regulatory approval:
Regulatory Assets Currently Earning a Return
Other Regulatory Assets Pending Final Regulatory Approval	$	0.2	$	0.1
Total Regulatory Assets Currently Earning a Return	0.2		0.1
Regulatory Assets Currently Not Earning a Return
Storm-Related Costs - Indiana	29.7		21.6
Other Regulatory Assets Pending Final Regulatory Approval	3.3		2.0
Total Regulatory Assets Currently Not Earning a Return	33.0		23.6
Total Regulatory Assets Pending Final Regulatory Approval	33.2		23.7
Regulatory assets approved for recovery:
Regulatory Assets Currently Earning a Return
Plant Retirement Costs - Unrecovered Plant	122.5		147.0		5 years
Rockport Plant Dry Sorbent Injection System and Selective Catalytic Reduction	46.9		56.6		5 years
Cook Plant Uprate Project	22.9		25.3		10 years
Deferred Cook Plant Life Cycle Management Project Costs - Michigan, FERC	11.1		12.1		11 years
Cook Plant Turbine - Indiana	8.4		9.0		15 years
Other Regulatory Assets Approved for Recovery	17.5		20.6		various
Total Regulatory Assets Currently Earning a Return	229.3		270.6
Regulatory Assets Currently Not Earning a Return
Cook Plant Nuclear Refueling Outage Levelization	55.7		81.2		2 years
Pension and OPEB Funded Status	25.4		26.9		12 years
Excess SO2 Allowance Inventory - Indiana	14.8		—		5 years
Unamortized Loss on Reacquired Debt	11.8		12.9		25 years
Environmental Cost Rider - Indiana	8.1		6.6		2 years
Postemployment Benefits	7.0		7.7		3 years
Demand Side Management - Indiana	—		10.3
Other Regulatory Assets Approved for Recovery	21.0		19.7		various
Total Regulatory Assets Currently Not Earning a Return	143.8		165.3
Total Regulatory Assets Approved for Recovery	373.1		435.9
Total Noncurrent Regulatory Assets	$	406.3	$	459.6

	I&M
	December 31,				Remaining Refund Period
Regulatory Liabilities:	2023		2022
	(in millions)
Current Regulatory Liabilities
Over-recovered Fuel Costs, Indiana - does not pay a return	$	23.2	$	—	1 year
Total Current Regulatory Liabilities	$	23.2	$	—
Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits
Regulatory liabilities pending final regulatory determination:
Regulatory Liabilities Currently Paying a Return
Income Taxes, Net (a) (b)	$	(103.0)	$	(87.7)
Total Regulatory Liabilities Currently Paying a Return	(103.0)		(87.7)
Regulatory Liabilities Currently Not Paying a Return
FERC 2021 Transmission Formula Rate Challenge Refunds	22.8		—
Total Regulatory Liabilities Currently Not Paying a Return	22.8		—
Total Regulatory Liabilities Pending Final Regulatory Determination	(80.2)		(87.7)
Regulatory liabilities approved for payment:
Regulatory Liabilities Currently Paying a Return
Asset Removal Costs	168.1		170.7		(c)
Income Taxes, Net (a)	116.8		168.6		(d)
Renewable Energy Surcharge - Michigan	26.6		23.2		2 years
Other Regulatory Liabilities Approved for Payment	0.1		3.0		various
Total Regulatory Liabilities Currently Paying a Return	311.6		365.5
Regulatory Liabilities Currently Not Paying a Return
Excess Nuclear Decommissioning Funding	1,721.9		1,318.5		(e)
Spent Nuclear Fuel	47.6		45.8		(e)
Demand Side Management - Indiana	16.7		—		2 years
Deferred Investment Tax Credits	15.8		17.4		27 years
PJM Costs and Off-system Sales Margin Sharing - Indiana	14.1		34.2		2 years
Other Regulatory Liabilities Approved for Payment	4.8		8.5		various
Total Regulatory Liabilities Currently Not Paying a Return	1,820.9		1,424.4
Total Regulatory Liabilities Approved for Payment	2,132.5		1,789.9
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits	$	2,052.3	$	1,702.2

(a)Predominately pays a return due to the inclusion of Excess ADIT in rate base.

(b)Represents an income tax related regulatory asset, which is presented within net regulatory liabilities on the balance sheet.

(c)Relieved as removal costs are incurred.

(d)Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $25 million and $42 million for the years ended December 31, 2023 and 2022, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2023 is to be refunded over 5 years.

(e)Relieved when plant is decommissioned.

	OPCo
	December 31,				Remaining Recovery Period
Regulatory Assets:	2023		2022
	(in millions)
Current Regulatory Assets
Under-recovered Fuel Costs - does not earn a return	$	—	$	3.8	1 year
Total Current Regulatory Assets	$	—	$	3.8
Noncurrent Regulatory Assets
Regulatory assets pending final regulatory approval:
Regulatory Assets Currently Not Earning a Return
Storm-Related Costs	$	23.6	$	33.8
Total Regulatory Assets Pending Final Regulatory Approval	23.6		33.8
Regulatory assets approved for recovery:
Regulatory Assets Currently Earning a Return
Ohio Basic Transmission Cost Rider	42.2		14.3		2 years
Ohio Distribution Decoupling	1.8		19.5		2 years
Ohio Economic Development Rider	—		1.1
Total Regulatory Assets Currently Earning a Return	44.0		34.9
Regulatory Assets Currently Not Earning a Return
Pension and OPEB Funded Status	147.1		142.7		12 years
Unrealized Loss on Forward Commitments	50.8		40.0		9 years
OVEC Purchased Power	50.1		—		2 years
Ohio Enhanced Service Reliability Plan	35.3		33.3		2 years
Ohio Distribution Investment Rider	35.3		2.3		2 years
Storm-Related Costs	30.9		—		1 year
Smart Grid Costs	26.3		25.4		2 years
Other Regulatory Assets Approved for Recovery	11.6		14.9		various
Total Regulatory Assets Currently Not Earning a Return	387.4		258.6
Total Regulatory Assets Approved for Recovery	431.4		293.5
Total Noncurrent Regulatory Assets	$	455.0	$	327.3

	OPCo
	December 31,				Remaining Refund Period
	2023		2022
Regulatory Liabilities:	(in millions)
Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits
Regulatory liabilities pending final regulatory determination:
Regulatory Liabilities Currently Not Paying a Return
FERC 2021 Transmission Formula Rate Challenge Refunds	$	57.0	$	—
Other Regulatory Liabilities Pending Final Regulatory Determination	0.2		0.2
Total Regulatory Liabilities Pending Final Regulatory Determination	57.2		0.2
Regulatory liabilities approved for payment:
Regulatory Liabilities Currently Paying a Return
Asset Removal Costs	475.5		466.5		(a)
Income Taxes, Net (b)	408.2		451.9		(c)
Total Regulatory Liabilities Currently Paying a Return	883.7		918.4
Regulatory Liabilities Currently Not Paying a Return
Over-recovered Fuel Costs	26.1		32.2		9 years
Peak Demand Reduction/Energy Efficiency	23.2		23.6		2 years
PJM Transmission Enhancement Refund	9.8		14.7		2 years
OVEC Purchased Power	—		47.1
Other Regulatory Liabilities Approved for Payment	3.6		7.8		various
Total Regulatory Liabilities Currently Not Paying a Return	62.7		125.4
Total Regulatory Liabilities Approved for Payment	946.4		1,043.8
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits	$	1,003.6	$	1,044.0

(a)Relieved as removal costs are incurred.

(b)Predominately pays a return due to the inclusion of Excess ADIT in rate base.

(c)Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $132 million and $162 million for the years ended December 31, 2023 and 2022, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2023 is to be refunded over 5 years.

	PSO
	December 31,				Remaining Recovery Period
	2023		2022
Regulatory Assets:	(in millions)
Current Regulatory Assets
Under-recovered Fuel Costs - earns a return	$	118.3	$	178.7	1 year
Total Current Regulatory Assets	$	118.3	$	178.7
Noncurrent Regulatory Assets
Regulatory assets pending final regulatory approval:
Regulatory Assets Currently Not Earning a Return
Storm-Related Costs	$	88.5	$	25.5
Other Regulatory Assets Pending Final Regulatory Approval	0.2		0.1
Total Regulatory Assets Pending Final Regulatory Approval	88.7		25.6
Regulatory assets approved for recovery:
Regulatory Assets Currently Earning a Return
Plant Retirement Costs - Unrecovered Plant (a)	254.1		240.6		23 years
Storm-Related Costs	26.2		8.4		5 years
Environmental Control Projects	22.5		23.9		17 years
Meter Replacement Costs	14.1		18.1		4 years
Long-term Under-recovered Fuel Costs - Oklahoma	—		252.7
Other Regulatory Assets Approved for Recovery	8.4		9.1		various
Total Regulatory Assets Currently Earning a Return	325.3		552.8
Regulatory Assets Currently Not Earning a Return
Pension and OPEB Funded Status	62.6		55.2		12 years
Unrealized Loss on Forward Commitments	29.9		—		2 years
Other Regulatory Assets Approved for Recovery	16.2		20.1		various
Total Regulatory Assets Currently Not Earning a Return	108.7		75.3
Total Regulatory Assets Approved for Recovery	434.0		628.1
Total Noncurrent Regulatory Assets	$	522.7	$	653.7

(a)Northeastern Plant, Unit 3 is approved for recovery through 2040, but expected to retire in 2026. PSO records a regulatory asset for accelerated depreciation. See “Regulated Generating Units to be Retired” section above for additional information.

	PSO
	December 31,				Remaining Refund Period
	2023		2022
Regulatory Liabilities:	(in millions)
Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits
Regulatory liabilities pending final regulatory determination:
Regulatory Liabilities Currently Paying a Return
Income Taxes, Net (a)	$	—	$	51.3
Total Regulatory Liabilities Currently Paying a Return	—		51.3
Regulatory Liabilities Currently Not Paying a Return
FERC 2021 Transmission Formula Rate Challenge Refunds	1.2		—
Total Regulatory Liabilities Currently Not Paying a Return	1.2		—
Total Regulatory Liabilities Pending Final Regulatory Determination	1.2		51.3
Regulatory liabilities approved for payment:
Regulatory Liabilities Currently Paying a Return
Income Taxes, Net (a)	395.7		380.1		(b)
Asset Removal Costs	317.5		316.3		(c)
Total Regulatory Liabilities Currently Paying a Return	713.2		696.4
Regulatory Liabilities Currently Not Paying a Return
Deferred Investment Tax Credits	47.2		48.2		18 years
Other Regulatory Liabilities Approved for Payment	4.0		13.2		various
Total Regulatory Liabilities Currently Not Paying a Return	51.2		61.4
Total Regulatory Liabilities Approved for Payment	764.4		757.8
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits	$	765.6	$	809.1

(a)Predominately pays a return due to the inclusion of Excess ADIT in rate base.

(b)Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $51 million and $21 million for the years ended December 31, 2023 and 2022, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2023 is to be refunded over 1 year.

(c)Relieved as removal costs are incurred.

	SWEPCo
	December 31,				Remaining Recovery Period
	2023		2022
Regulatory Assets:	(in millions)
Current Regulatory Assets
Under-recovered Fuel Costs - earns a return (a)	$	76.9	$	257.2	1 year
Unrecovered Winter Storm Fuel Costs - earns a return (b)	93.9		95.8		1 year
Total Current Regulatory Assets	$	170.8	$	353.0
Noncurrent Regulatory Assets
Regulatory assets pending final regulatory approval:
Regulatory Assets Currently Earning a Return
Welsh Plant, Units 1 and 3 Accelerated Depreciation	$	125.6	$	85.6
Pirkey Plant Accelerated Depreciation	114.4		116.5
Unrecovered Winter Storm Fuel Costs (b)	60.1		84.6
Dolet Hills Power Station Accelerated Depreciation (c)	12.0		9.7
Other Regulatory Assets Pending Final Regulatory Approval	26.0		34.5
Total Regulatory Assets Currently Earning a Return	338.1		330.9
Regulatory Assets Currently Not Earning a Return
Storm-Related Costs - Louisiana, Texas	56.0		151.5
Asset Retirement Obligation - Louisiana	—		11.8
Other Regulatory Assets Pending Final Regulatory Approval	13.7		16.0
Total Regulatory Assets Currently Not Earning a Return	69.7		179.3
Total Regulatory Assets Pending Final Regulatory Approval	407.8		510.2
Regulatory assets approved for recovery:
Regulatory Assets Currently Earning a Return
Storm-Related Costs - Louisiana	144.7		—		2 years
Unrecovered Winter Storm Fuel Costs (b)	99.3		148.6		4 years
Fuel Mine Closure Costs - Texas	74.3		—		12 years
Pirkey Plant Accelerated Depreciation - Louisiana	65.8		63.0		9 years
Plant Retirement Costs - Unrecovered Plant, Arkansas	44.4		13.1		19 years
Plant Retirement Costs - Unrecovered Plant, Dolet Hills Power Station - Louisiana	40.8		45.1		9 years
Environmental Controls Projects	8.9		10.0		9 years
Plant Retirement Costs - Unrecovered Plant, Welsh Plant, Unit 2 - Louisiana	—		35.2
Other Regulatory Assets Approved for Recovery	4.9		6.8		various
Total Regulatory Assets Currently Earning a Return	483.1		321.8
Regulatory Assets Currently Not Earning a Return
Pension and OPEB Funded Status	109.2		96.2		12 years
Plant Retirement Costs - Unrecovered Plant, Texas	48.7		51.7		23 years
North Central Wind Rider	20.2		6.4		2 years
Plant Retirement Costs - Unrecovered Plant, Arkansas	17.3		21.1		4 years
Unrealized Loss on Forward Commitments	15.4		—		2 years
Other Regulatory Assets Approved for Recovery	30.1		35.0		various
Total Regulatory Assets Currently Not Earning a Return	240.9		210.4
Total Regulatory Assets Approved for Recovery	724.0		532.2
Total Noncurrent Regulatory Assets	$	1,131.8	$	1,042.4

(a)Amounts include Arkansas and Texas jurisdictions.

(b)See “February 2021 Severe Winter Weather Impacts in SPP” section of SWEPCo Rate Matters in Note 4 for additional information.

(c)Amounts include the FERC jurisdiction.

	SWEPCo
	December 31,				Remaining Refund Period
	2023		2022
Regulatory Liabilities:	(in millions)
Current Regulatory Liabilities
Over-recovered Fuel Costs - pays a return (a)	$	3.3	$	1.4	1 year
Total Current Regulatory Liabilities	$	3.3	$	1.4
Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits
Regulatory liabilities pending final regulatory determination:
Regulatory Liabilities Currently Paying a Return
Income Taxes, Net (b)	$	7.0	$	7.0
Total Regulatory Liabilities Pending Final Regulatory Determination	7.0		7.0
Regulatory liabilities approved for payment:
Regulatory Liabilities Currently Paying a Return
Asset Removal Costs	443.2		481.2		(c)
Income Taxes, Net (b)	292.4		327.6		(d)
Other Regulatory Liabilities Approved for Payment	4.4		2.2		various
Total Regulatory Liabilities Currently Paying a Return	740.0		811.0
Regulatory Liabilities Currently Not Paying a Return
Other Regulatory Liabilities Approved for Payment	9.1		7.7		various
Total Regulatory Liabilities Currently Not Paying a Return	9.1		7.7
Total Regulatory Liabilities Approved for Payment	749.1		818.7
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits	$	756.1	$	825.7

(a)Amounts include Louisiana jurisdiction.

(b)Predominately pays a return due to the inclusion of Excess ADIT in rate base.

(c)Relieved as removal costs are incurred.

(d)Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets.