Regulatory Matters (Tables)

12 Months Ended

Dec. 31, 2023

Public Utilities, General Disclosures [Line Items]

Schedule of Regulatory Assets

The following tables present the regulatory assets and liabilities recorded on the Consolidated Balance Sheets of Duke Energy and Progress Energy. See separate tables below for balances by individual registrant.

	Duke Energy				Progress Energy
	December 31,				December 31,
(in millions)	2023		2022		2023		2022
Regulatory Assets
AROs – coal ash	$	3,214	$	3,205	$	1,230	$	1,429
AROs – nuclear and other	1,179		945		1,127		884
Deferred fuel and purchased power	2,486		3,866		1,173		2,060
Accrued pension and OPEB	2,389		2,336		757		759
Storm cost securitized balance, net	890		940		682		720
Nuclear asset securitized balance, net	830		881		830		881
Debt fair value adjustment	774		829		—		—
Hedge costs deferrals	749		378		323		128
Storm cost deferrals	407		687		298		559
COR regulatory asset	371		221		337		221
Post-in-service carrying costs (PISCC) and deferred operating expenses	357		359		42		42
Retired generation facilities	275		316		220		243
Deferred asset – Lee and Harris COLA	252		288		15		21
Customer connect project	251		271		125		136
Advanced metering infrastructure (AMI)	243		283		92		111
Incremental COVID-19 expenses	237		210		80		78
Vacation accrual	228		222		43		43
Grid Deferral	210		136		51		40
Demand side management (DSM)/Energy efficiency (EE)	201		189		191		188
CEP deferral	193		190		—		—
NCEMPA deferrals	172		157		172		157
Derivatives – natural gas supply contracts	147		168		—		—
Deferred pipeline integrity costs	133		121		—		—
Nuclear deferral	131		154		42		64
COR settlement	115		120		30		32
Decoupling	115		42		15		—
Deferred coal ash handling system costs	86		92		21		25
Qualifying facility contract buyouts	68		81		68		81
Network Integration Transmission Services deferral	31		23		—		—
Transmission expansion obligation	30		31		—		—
East Bend deferrals	28		33		—		—
Propane caverns	26		26		—		—
Tennessee ARM Deferral	20		3		—		—
Other	428		327		127		77
Total regulatory assets	17,266		18,130		8,091		8,979
Less: Current portion	3,648		3,485		1,661		1,833
Total noncurrent regulatory assets	$	13,618	$	14,645	$	6,430	$	7,146
Regulatory Liabilities
Net regulatory liability related to income taxes	$	5,901	$	6,462	$	2,008	$	2,192
COR regulatory liability	5,497		5,151		2,805		2,269
AROs – nuclear and other	1,673		1,038		—		—
Hedge cost deferrals	443		683		208		252
Accrued pension and OPEB	266		211		—		—
Deferred fuel and purchased power	137		35		14		—
DSM/EE	89		88		—		—
DOE Settlement	32		154		32		154
Provision for rate refunds	15		78		4		28
Other	1,355		1,148		430		434
Total regulatory liabilities	15,408		15,048		5,501		5,329
Less: Current portion	1,369		1,466		418		576
Total noncurrent regulatory liabilities	$	14,039	$	13,582	$	5,083	$	4,753

Schedule of Regulatory Liabilities

The following tables present the regulatory assets and liabilities recorded on the Consolidated Balance Sheets of Duke Energy and Progress Energy. See separate tables below for balances by individual registrant.

	Duke Energy				Progress Energy
	December 31,				December 31,
(in millions)	2023		2022		2023		2022
Regulatory Assets
AROs – coal ash	$	3,214	$	3,205	$	1,230	$	1,429
AROs – nuclear and other	1,179		945		1,127		884
Deferred fuel and purchased power	2,486		3,866		1,173		2,060
Accrued pension and OPEB	2,389		2,336		757		759
Storm cost securitized balance, net	890		940		682		720
Nuclear asset securitized balance, net	830		881		830		881
Debt fair value adjustment	774		829		—		—
Hedge costs deferrals	749		378		323		128
Storm cost deferrals	407		687		298		559
COR regulatory asset	371		221		337		221
Post-in-service carrying costs (PISCC) and deferred operating expenses	357		359		42		42
Retired generation facilities	275		316		220		243
Deferred asset – Lee and Harris COLA	252		288		15		21
Customer connect project	251		271		125		136
Advanced metering infrastructure (AMI)	243		283		92		111
Incremental COVID-19 expenses	237		210		80		78
Vacation accrual	228		222		43		43
Grid Deferral	210		136		51		40
Demand side management (DSM)/Energy efficiency (EE)	201		189		191		188
CEP deferral	193		190		—		—
NCEMPA deferrals	172		157		172		157
Derivatives – natural gas supply contracts	147		168		—		—
Deferred pipeline integrity costs	133		121		—		—
Nuclear deferral	131		154		42		64
COR settlement	115		120		30		32
Decoupling	115		42		15		—
Deferred coal ash handling system costs	86		92		21		25
Qualifying facility contract buyouts	68		81		68		81
Network Integration Transmission Services deferral	31		23		—		—
Transmission expansion obligation	30		31		—		—
East Bend deferrals	28		33		—		—
Propane caverns	26		26		—		—
Tennessee ARM Deferral	20		3		—		—
Other	428		327		127		77
Total regulatory assets	17,266		18,130		8,091		8,979
Less: Current portion	3,648		3,485		1,661		1,833
Total noncurrent regulatory assets	$	13,618	$	14,645	$	6,430	$	7,146
Regulatory Liabilities
Net regulatory liability related to income taxes	$	5,901	$	6,462	$	2,008	$	2,192
COR regulatory liability	5,497		5,151		2,805		2,269
AROs – nuclear and other	1,673		1,038		—		—
Hedge cost deferrals	443		683		208		252
Accrued pension and OPEB	266		211		—		—
Deferred fuel and purchased power	137		35		14		—
DSM/EE	89		88		—		—
DOE Settlement	32		154		32		154
Provision for rate refunds	15		78		4		28
Other	1,355		1,148		430		434
Total regulatory liabilities	15,408		15,048		5,501		5,329
Less: Current portion	1,369		1,466		418		576
Total noncurrent regulatory liabilities	$	14,039	$	13,582	$	5,083	$	4,753

Schedule of Potential Plant Retirements

Duke Energy Carolinas

Public Utilities, General Disclosures [Line Items]

Schedule of Regulatory Assets

The following tables present the regulatory assets and liabilities recorded on Duke Energy Carolinas' Consolidated Balance Sheets.

	December 31,				Earns/Pays	Recovery/Refund
(in millions)	2023		2022		a Return	Period Ends
Regulatory Assets(a)
AROs – coal ash	$	1,559	$	1,391	(g)	(b)
Deferred fuel and purchased power(i)	1,293		1,614		(e)	2025
Accrued pension and OPEB	671		614			(h)
Storm cost securitized balance, net	208		220		Yes	2041
Hedge costs deferrals	405		228			(b)
Storm cost deferrals	97		114		Yes	(b)
PISCC and deferred operating expenses	48		47		Yes	(b)
Retired generation facilities(c)	26		39		Yes	(b)
Deferred asset – Lee COLA	237		267			(b)
Customer connect project(c)	58		62		Yes	(b)
AMI(c)	125		139		Yes	(b)
Incremental COVID-19 expenses	152		127		Yes	(b)
Vacation accrual	87		84			2024
Grid Deferral(c)	159		96		Yes	(b)
Nuclear deferral	89		90			2025
COR settlement(c)	85		88		Yes	(b)
Deferred coal ash handling system costs(c)	65		67		Yes	(b)
Other	116		101			(b)
Total regulatory assets	5,480		5,388
Less: Current portion	1,564		1,095
Total noncurrent regulatory assets	$	3,916	$	4,293
Regulatory Liabilities(a)
Net regulatory liability related to income taxes(d)	$	2,200	$	2,475	Yes	(b)
COR regulatory liability(c)	1,641		1,769		Yes	(f)
AROs – nuclear and other	1,673		1,038			(b)
Hedge cost deferrals	158		350			(b)
Accrued pension and OPEB	106		44			(h)
Deferred fuel and purchased power(i)	85		—		(e)	2025
DSM/EE(c)	87		86		Yes	(j)
Provision for rate refunds(c)	11		50		Yes	(b)
Other	616		501			(b)
Total regulatory liabilities	6,577		6,313
Less: Current portion	587		530
Total noncurrent regulatory liabilities	$	5,990	$	5,783

(a)    Regulatory assets and liabilities are excluded from rate base unless otherwise noted.

(b)    The expected recovery or refund period varies or has not been determined.

(c)     Included in rate base.

(d)    Includes regulatory liabilities related to the change in the federal tax rate as a result of the Tax Act and the change in the North Carolina tax rate. Portions are included in rate base.

(e)    Pays interest on over-recovered costs in North Carolina. Includes certain purchased power costs in North Carolina and South Carolina and costs of distributed energy in South Carolina. The asset balance principally relates to North Carolina costs while the liability balance relates to South Carolina.

(f)    Recovered over the life of the associated assets.

(g)    Earns a debt and equity return on coal ash expenditures for North Carolina and South Carolina retail customers as permitted by various regulatory orders.

(h)    Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 23 for additional detail.

(i)    Duke Energy Carolinas submitted a fuel filing to the NCUC in February 2023 for recovery of $998 million, which included deferrals through December 2022. The NCUC approved recovery of this balance through December 2024. The next filing will be made in the first quarter of 2024. Duke Energy Carolinas submitted a fuel filing to the PSCSC in August 2023 for recovery of $310 million, which included deferrals through May 2023. The PSCSC approved recovery of this balance through October 2024. The next filing will be made in the third quarter of 2024.

(j)    Includes incentives on DSM/EE investments and is recovered or refunded through an annual rider mechanism.

Schedule of Regulatory Liabilities

The following tables present the regulatory assets and liabilities recorded on Duke Energy Carolinas' Consolidated Balance Sheets.

	December 31,				Earns/Pays	Recovery/Refund
(in millions)	2023		2022		a Return	Period Ends
Regulatory Assets(a)
AROs – coal ash	$	1,559	$	1,391	(g)	(b)
Deferred fuel and purchased power(i)	1,293		1,614		(e)	2025
Accrued pension and OPEB	671		614			(h)
Storm cost securitized balance, net	208		220		Yes	2041
Hedge costs deferrals	405		228			(b)
Storm cost deferrals	97		114		Yes	(b)
PISCC and deferred operating expenses	48		47		Yes	(b)
Retired generation facilities(c)	26		39		Yes	(b)
Deferred asset – Lee COLA	237		267			(b)
Customer connect project(c)	58		62		Yes	(b)
AMI(c)	125		139		Yes	(b)
Incremental COVID-19 expenses	152		127		Yes	(b)
Vacation accrual	87		84			2024
Grid Deferral(c)	159		96		Yes	(b)
Nuclear deferral	89		90			2025
COR settlement(c)	85		88		Yes	(b)
Deferred coal ash handling system costs(c)	65		67		Yes	(b)
Other	116		101			(b)
Total regulatory assets	5,480		5,388
Less: Current portion	1,564		1,095
Total noncurrent regulatory assets	$	3,916	$	4,293
Regulatory Liabilities(a)
Net regulatory liability related to income taxes(d)	$	2,200	$	2,475	Yes	(b)
COR regulatory liability(c)	1,641		1,769		Yes	(f)
AROs – nuclear and other	1,673		1,038			(b)
Hedge cost deferrals	158		350			(b)
Accrued pension and OPEB	106		44			(h)
Deferred fuel and purchased power(i)	85		—		(e)	2025
DSM/EE(c)	87		86		Yes	(j)
Provision for rate refunds(c)	11		50		Yes	(b)
Other	616		501			(b)
Total regulatory liabilities	6,577		6,313
Less: Current portion	587		530
Total noncurrent regulatory liabilities	$	5,990	$	5,783

(a)    Regulatory assets and liabilities are excluded from rate base unless otherwise noted.

(b)    The expected recovery or refund period varies or has not been determined.

(c)     Included in rate base.

(d)    Includes regulatory liabilities related to the change in the federal tax rate as a result of the Tax Act and the change in the North Carolina tax rate. Portions are included in rate base.

(e)    Pays interest on over-recovered costs in North Carolina. Includes certain purchased power costs in North Carolina and South Carolina and costs of distributed energy in South Carolina. The asset balance principally relates to North Carolina costs while the liability balance relates to South Carolina.

(f)    Recovered over the life of the associated assets.

(g)    Earns a debt and equity return on coal ash expenditures for North Carolina and South Carolina retail customers as permitted by various regulatory orders.

(h)    Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 23 for additional detail.

(i)    Duke Energy Carolinas submitted a fuel filing to the NCUC in February 2023 for recovery of $998 million, which included deferrals through December 2022. The NCUC approved recovery of this balance through December 2024. The next filing will be made in the first quarter of 2024. Duke Energy Carolinas submitted a fuel filing to the PSCSC in August 2023 for recovery of $310 million, which included deferrals through May 2023. The PSCSC approved recovery of this balance through October 2024. The next filing will be made in the third quarter of 2024.

(j)    Includes incentives on DSM/EE investments and is recovered or refunded through an annual rider mechanism.

Duke Energy Progress

Public Utilities, General Disclosures [Line Items]

Schedule of Regulatory Assets

The following tables present the regulatory assets and liabilities recorded on Duke Energy Progress' Consolidated Balance Sheets.

	December 31,				Earns/Pays	Recovery/Refund
(in millions)	2023		2022		a Return	Period Ends
Regulatory Assets(a)
AROs – coal ash	$	1,218	$	1,418	(g)	(b)
AROs – nuclear and other	1,110		869			(c)
Deferred fuel and purchased power(l)	579		705		(e)	2025
Accrued pension and OPEB	408		417			(j)
Storm cost securitized balance, net	682		720		Yes	2041
Hedge costs deferrals	260		55			(b)
Storm cost deferrals	228		234		Yes	(b)
PISCC and deferred operating expenses	42		42		Yes	2054
Retired generation facilities(d)	126		149		Yes	(b)
Deferred asset – Harris COLA	15		21			(b)
Customer connect project(d)	49		54		Yes	(b)
AMI(d)	68		81		Yes	(b)
Incremental COVID-19 expenses	80		78			(b)
Vacation accrual	43		43			2024
Grid Deferral(d)	51		40		Yes	(b)
DSM/EE(d)	182		180		Yes	(h)
NCEMPA deferrals(d)	172		157		(f)	2042
Nuclear deferral	42		64			2025
COR settlement(d)	30		32		Yes	(b)
Decoupling	15		—		Yes	(b)
Deferred coal ash handling system costs(d)	21		25		Yes	(b)
Other	67		30			(b)
Total regulatory assets	5,488		5,414
Less: Current portion	942		690
Total noncurrent regulatory assets	$	4,546	$	4,724
Regulatory Liabilities(a)
Net regulatory liability related to income taxes(k)	$	1,420	$	1,559	Yes	(b)
COR regulatory liability	2,805		2,269			(i)
Hedge cost deferrals	87		252			(b)
Deferred fuel and purchased power(l)	14		—		(e)	2025
Provision for rate refunds(d)	4		28		Yes	(b)
Other	345		344			(b)
Total regulatory liabilities	4,675		4,452
Less: Current portion	300		332
Total noncurrent regulatory liabilities	$	4,375	$	4,120

(a)    Regulatory assets and liabilities are excluded from rate base unless otherwise noted.

(b)    The expected recovery or refund period varies or has not been determined.

(c)    Recovery period for costs related to nuclear facilities runs through the decommissioning period of each unit.

(d)    Included in rate base.

(e)    Pays interest on over-recovered costs in North Carolina. Includes certain purchased power costs in North Carolina and South Carolina and costs of distributed energy in South Carolina. The asset balance principally relates to North Carolina costs while the liability balance relates to South Carolina.

(f)    South Carolina retail allocated costs are earning a return.

(g)    Earns a debt and equity return on coal ash expenditures for North Carolina and South Carolina retail customers as permitted by various regulatory orders.

(h)    Includes incentives on DSM/EE investments and is recovered through an annual rider mechanism.

(i)    Recovered over the life of the associated assets.

(j)    Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 23 for additional detail.

(k)    Includes regulatory liabilities related to the change in the federal tax rate as a result of the Tax Act and the change in the North Carolina tax rate. Portions are included in rate base.

(l)    Duke Energy Progress submitted a fuel filing to the NCUC in June 2023 for recovery of $445 million, which included deferrals through March 2023. The NCUC approved recovery of this balance through November 2024. The next filing will be made in the second quarter of 2024. Duke Energy Progress submitted a fuel filing to the PSCSC in May 2023 for recovery of $79 million, which included deferrals through February 2023. The PSCSC approved recovery of this balance through July 2024. The next filing will be made in the second quarter of 2024.

Schedule of Regulatory Liabilities

The following tables present the regulatory assets and liabilities recorded on Duke Energy Progress' Consolidated Balance Sheets.

	December 31,				Earns/Pays	Recovery/Refund
(in millions)	2023		2022		a Return	Period Ends
Regulatory Assets(a)
AROs – coal ash	$	1,218	$	1,418	(g)	(b)
AROs – nuclear and other	1,110		869			(c)
Deferred fuel and purchased power(l)	579		705		(e)	2025
Accrued pension and OPEB	408		417			(j)
Storm cost securitized balance, net	682		720		Yes	2041
Hedge costs deferrals	260		55			(b)
Storm cost deferrals	228		234		Yes	(b)
PISCC and deferred operating expenses	42		42		Yes	2054
Retired generation facilities(d)	126		149		Yes	(b)
Deferred asset – Harris COLA	15		21			(b)
Customer connect project(d)	49		54		Yes	(b)
AMI(d)	68		81		Yes	(b)
Incremental COVID-19 expenses	80		78			(b)
Vacation accrual	43		43			2024
Grid Deferral(d)	51		40		Yes	(b)
DSM/EE(d)	182		180		Yes	(h)
NCEMPA deferrals(d)	172		157		(f)	2042
Nuclear deferral	42		64			2025
COR settlement(d)	30		32		Yes	(b)
Decoupling	15		—		Yes	(b)
Deferred coal ash handling system costs(d)	21		25		Yes	(b)
Other	67		30			(b)
Total regulatory assets	5,488		5,414
Less: Current portion	942		690
Total noncurrent regulatory assets	$	4,546	$	4,724
Regulatory Liabilities(a)
Net regulatory liability related to income taxes(k)	$	1,420	$	1,559	Yes	(b)
COR regulatory liability	2,805		2,269			(i)
Hedge cost deferrals	87		252			(b)
Deferred fuel and purchased power(l)	14		—		(e)	2025
Provision for rate refunds(d)	4		28		Yes	(b)
Other	345		344			(b)
Total regulatory liabilities	4,675		4,452
Less: Current portion	300		332
Total noncurrent regulatory liabilities	$	4,375	$	4,120

(a)    Regulatory assets and liabilities are excluded from rate base unless otherwise noted.

(b)    The expected recovery or refund period varies or has not been determined.

(c)    Recovery period for costs related to nuclear facilities runs through the decommissioning period of each unit.

(d)    Included in rate base.

(e)    Pays interest on over-recovered costs in North Carolina. Includes certain purchased power costs in North Carolina and South Carolina and costs of distributed energy in South Carolina. The asset balance principally relates to North Carolina costs while the liability balance relates to South Carolina.

(f)    South Carolina retail allocated costs are earning a return.

(g)    Earns a debt and equity return on coal ash expenditures for North Carolina and South Carolina retail customers as permitted by various regulatory orders.

(h)    Includes incentives on DSM/EE investments and is recovered through an annual rider mechanism.

(i)    Recovered over the life of the associated assets.

(j)    Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 23 for additional detail.

(k)    Includes regulatory liabilities related to the change in the federal tax rate as a result of the Tax Act and the change in the North Carolina tax rate. Portions are included in rate base.

(l)    Duke Energy Progress submitted a fuel filing to the NCUC in June 2023 for recovery of $445 million, which included deferrals through March 2023. The NCUC approved recovery of this balance through November 2024. The next filing will be made in the second quarter of 2024. Duke Energy Progress submitted a fuel filing to the PSCSC in May 2023 for recovery of $79 million, which included deferrals through February 2023. The PSCSC approved recovery of this balance through July 2024. The next filing will be made in the second quarter of 2024.

Duke Energy Florida

Public Utilities, General Disclosures [Line Items]

Schedule of Regulatory Assets

The following tables present the regulatory assets and liabilities recorded on Duke Energy Florida's Consolidated Balance Sheets.

	December 31,				Earns/Pays	Recovery/Refund
(in millions)	2023		2022		a Return	Period Ends
Regulatory Assets(a)
AROs – coal ash	$	12	$	11		(b)
AROs – nuclear and other	17		15			(b)
Deferred fuel and purchased power(g)	594		1,355		(e)	2024
Accrued pension and OPEB(c)	349		342		Yes	(f)
Nuclear asset securitized balance, net	830		881			2036
Hedge costs deferrals(c)	63		73		Yes	2038
Storm cost deferrals(c)	70		325		(e)	(b)
COR regulatory asset	337		221		(d)	(b)
Retired generation facilities(c)	94		94		Yes	2044
Customer connect project(c)	76		82		Yes	2037
AMI(c)	24		30		Yes	2032
Qualifying facility contract buyouts(c)	68		81		Yes	2034
Other	69		55		(d)	(b)
Total regulatory assets	2,603		3,565
Less: Current portion	720		1,143
Total noncurrent regulatory assets	$	1,883	$	2,422
Regulatory Liabilities(a)
Net regulatory liability related to income taxes(c)	$	588	$	633		(b)
Hedge cost deferrals	121		—			(b)
DOE Settlement	32		154			2024
Other	85		90		(d)	(b)
Total regulatory liabilities	826		877
Less: Current portion	118		244
Total noncurrent regulatory liabilities	$	708	$	633

(a)    Regulatory assets and liabilities are excluded from rate base unless otherwise noted.

(b)    The expected recovery or refund period varies or has not been determined.

(c)    Included in rate base.

(d)    Certain costs earn/pay a return.

(e)    Earns commercial paper rate.

(f)    Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 23 for additional detail.

(g)    On March 6, 2023, the FPSC approved Duke Energy Florida's amended February 2023 fuel filing recovery of $469 million, which included the 2022 actual under-recovery of $1.2 billion, offset by projected declining fuel costs in 2023 due to lower natural gas prices. The approved 21-month recovery period for the actual 2022 under-recovery is April 2023 through December 2024; the reduction in 2023 fuel costs were approved to be returned over 9-months from April 2023 through December 2023. Duke Energy Florida made its most recent fuel filing in September 2023. On November 1, 2023, the FPSC approved Duke Energy Florida's September 2023 fuel filing, which included the proposed fuel factors for 2024. In addition to the under-recoveries approved above, that filing also included a re-projected 2023 over-recovery of approximately $120 million that will be returned to customers January 2024 through December 2024.

Schedule of Regulatory Liabilities

The following tables present the regulatory assets and liabilities recorded on Duke Energy Florida's Consolidated Balance Sheets.

	December 31,				Earns/Pays	Recovery/Refund
(in millions)	2023		2022		a Return	Period Ends
Regulatory Assets(a)
AROs – coal ash	$	12	$	11		(b)
AROs – nuclear and other	17		15			(b)
Deferred fuel and purchased power(g)	594		1,355		(e)	2024
Accrued pension and OPEB(c)	349		342		Yes	(f)
Nuclear asset securitized balance, net	830		881			2036
Hedge costs deferrals(c)	63		73		Yes	2038
Storm cost deferrals(c)	70		325		(e)	(b)
COR regulatory asset	337		221		(d)	(b)
Retired generation facilities(c)	94		94		Yes	2044
Customer connect project(c)	76		82		Yes	2037
AMI(c)	24		30		Yes	2032
Qualifying facility contract buyouts(c)	68		81		Yes	2034
Other	69		55		(d)	(b)
Total regulatory assets	2,603		3,565
Less: Current portion	720		1,143
Total noncurrent regulatory assets	$	1,883	$	2,422
Regulatory Liabilities(a)
Net regulatory liability related to income taxes(c)	$	588	$	633		(b)
Hedge cost deferrals	121		—			(b)
DOE Settlement	32		154			2024
Other	85		90		(d)	(b)
Total regulatory liabilities	826		877
Less: Current portion	118		244
Total noncurrent regulatory liabilities	$	708	$	633

(a)    Regulatory assets and liabilities are excluded from rate base unless otherwise noted.

(b)    The expected recovery or refund period varies or has not been determined.

(c)    Included in rate base.

(d)    Certain costs earn/pay a return.

(e)    Earns commercial paper rate.

(f)    Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 23 for additional detail.

(g)    On March 6, 2023, the FPSC approved Duke Energy Florida's amended February 2023 fuel filing recovery of $469 million, which included the 2022 actual under-recovery of $1.2 billion, offset by projected declining fuel costs in 2023 due to lower natural gas prices. The approved 21-month recovery period for the actual 2022 under-recovery is April 2023 through December 2024; the reduction in 2023 fuel costs were approved to be returned over 9-months from April 2023 through December 2023. Duke Energy Florida made its most recent fuel filing in September 2023. On November 1, 2023, the FPSC approved Duke Energy Florida's September 2023 fuel filing, which included the proposed fuel factors for 2024. In addition to the under-recoveries approved above, that filing also included a re-projected 2023 over-recovery of approximately $120 million that will be returned to customers January 2024 through December 2024.

Duke Energy Ohio

Public Utilities, General Disclosures [Line Items]

Schedule of Regulatory Assets

The following tables present the regulatory assets and liabilities recorded on Duke Energy Ohio's Consolidated Balance Sheets.

	December 31,				Earns/Pays	Recovery/Refund
(in millions)	2023		2022		a Return	Period Ends
Regulatory Assets(a)
AROs – coal ash	$	17	$	—	Yes	(b)
Deferred fuel and purchased gas costs	20		54			2024
Accrued pension and OPEB	123		129			(e)
Storm cost deferrals	12		14			2024
COR regulatory asset	34		—			(b)
PISCC and deferred operating expenses(c)	15		15		Yes	2083
Customer connect project	49		54			(b)
AMI	13		18			(b)
CEP deferral	193		190		Yes	(b)
Deferred pipeline integrity costs	30		28		Yes	(b)
Decoupling	25		—			(b)
Network Integration Transmission Services deferral	31		23		Yes	(b)
Transmission expansion obligation	30		31			(b)
East Bend deferrals(c)	28		33		Yes	(b)
Propane caverns	26		26			(b)
Other	103		69			(b)
Total regulatory assets	749		684
Less: Current portion	73		103
Total noncurrent regulatory assets	$	676	$	581
Regulatory Liabilities(a)
Net regulatory liability related to income taxes	$	466	$	496		(b)
COR regulatory liability	—		9			(d)
Accrued pension and OPEB	17		21			(e)
Deferred fuel and purchased gas costs	15		35			2024
Other	55		72			(b)
Total regulatory liabilities	553		633
Less: Current portion	56		99
Total noncurrent regulatory liabilities	$	497	$	534

(a)    Regulatory assets and liabilities are excluded from rate base unless otherwise noted.

(b)    The expected recovery or refund period varies or has not been determined.

(c)    Included in rate base.

(d)    Recovery over the life of the associated assets.

(e)    Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 23 for additional detail.

Schedule of Regulatory Liabilities

The following tables present the regulatory assets and liabilities recorded on Duke Energy Ohio's Consolidated Balance Sheets.

	December 31,				Earns/Pays	Recovery/Refund
(in millions)	2023		2022		a Return	Period Ends
Regulatory Assets(a)
AROs – coal ash	$	17	$	—	Yes	(b)
Deferred fuel and purchased gas costs	20		54			2024
Accrued pension and OPEB	123		129			(e)
Storm cost deferrals	12		14			2024
COR regulatory asset	34		—			(b)
PISCC and deferred operating expenses(c)	15		15		Yes	2083
Customer connect project	49		54			(b)
AMI	13		18			(b)
CEP deferral	193		190		Yes	(b)
Deferred pipeline integrity costs	30		28		Yes	(b)
Decoupling	25		—			(b)
Network Integration Transmission Services deferral	31		23		Yes	(b)
Transmission expansion obligation	30		31			(b)
East Bend deferrals(c)	28		33		Yes	(b)
Propane caverns	26		26			(b)
Other	103		69			(b)
Total regulatory assets	749		684
Less: Current portion	73		103
Total noncurrent regulatory assets	$	676	$	581
Regulatory Liabilities(a)
Net regulatory liability related to income taxes	$	466	$	496		(b)
COR regulatory liability	—		9			(d)
Accrued pension and OPEB	17		21			(e)
Deferred fuel and purchased gas costs	15		35			2024
Other	55		72			(b)
Total regulatory liabilities	553		633
Less: Current portion	56		99
Total noncurrent regulatory liabilities	$	497	$	534

(a)    Regulatory assets and liabilities are excluded from rate base unless otherwise noted.

(b)    The expected recovery or refund period varies or has not been determined.

(c)    Included in rate base.

(d)    Recovery over the life of the associated assets.

(e)    Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 23 for additional detail.

Duke Energy Indiana

Public Utilities, General Disclosures [Line Items]

Schedule of Regulatory Assets

The following tables present the regulatory assets and liabilities recorded on Duke Energy Indiana's Consolidated Balance Sheets.

	December 31,				Earns/Pays	Recovery/Refund
(in millions)	2023		2022		a Return	Period Ends
Regulatory Assets(a)
AROs – coal ash	$	408	$	385	Yes	(b)
Deferred fuel and purchased power	—		138			2024
Accrued pension and OPEB	208		214			(e)
Hedge costs deferrals	19		20			(b)
PISCC and deferred operating expenses(c)	252		255		Yes	(b)
Retired generation facilities(c)	29		34		Yes	2030
Customer connect project	19		19			(b)
AMI	13		15			2031
Other	48		44			(b)
Total regulatory assets	996		1,124
Less: Current portion	102		249
Total noncurrent regulatory assets	$	894	$	875
Regulatory Liabilities(a)
Net regulatory liability related to income taxes	$	794	$	840		(b)
COR regulatory liability	496		531			(d)
Hedge cost deferrals	77		81			(b)
Accrued pension and OPEB	109		104			(e)
Deferred fuel and purchased power	23		—			2024
Other	169		85			(b)
Total regulatory liabilities	1,668		1,641
Less: Current portion	209		187
Total noncurrent regulatory liabilities	$	1,459	$	1,454

(a)    Regulatory assets and liabilities are excluded from rate base unless otherwise noted.

(b)    The expected recovery or refund period varies or has not been determined.

(c)    Included in rate base.

(d)    Refunded over the life of the associated assets.

(e)    Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 23 for additional detail.

Schedule of Regulatory Liabilities

The following tables present the regulatory assets and liabilities recorded on Duke Energy Indiana's Consolidated Balance Sheets.

	December 31,				Earns/Pays	Recovery/Refund
(in millions)	2023		2022		a Return	Period Ends
Regulatory Assets(a)
AROs – coal ash	$	408	$	385	Yes	(b)
Deferred fuel and purchased power	—		138			2024
Accrued pension and OPEB	208		214			(e)
Hedge costs deferrals	19		20			(b)
PISCC and deferred operating expenses(c)	252		255		Yes	(b)
Retired generation facilities(c)	29		34		Yes	2030
Customer connect project	19		19			(b)
AMI	13		15			2031
Other	48		44			(b)
Total regulatory assets	996		1,124
Less: Current portion	102		249
Total noncurrent regulatory assets	$	894	$	875
Regulatory Liabilities(a)
Net regulatory liability related to income taxes	$	794	$	840		(b)
COR regulatory liability	496		531			(d)
Hedge cost deferrals	77		81			(b)
Accrued pension and OPEB	109		104			(e)
Deferred fuel and purchased power	23		—			2024
Other	169		85			(b)
Total regulatory liabilities	1,668		1,641
Less: Current portion	209		187
Total noncurrent regulatory liabilities	$	1,459	$	1,454

(a)    Regulatory assets and liabilities are excluded from rate base unless otherwise noted.

(b)    The expected recovery or refund period varies or has not been determined.

(c)    Included in rate base.

(d)    Refunded over the life of the associated assets.

(e)    Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 23 for additional detail.

Piedmont

Public Utilities, General Disclosures [Line Items]

Schedule of Regulatory Assets

The following tables present the regulatory assets and liabilities recorded on Piedmont's Consolidated Balance Sheets.

	December 31,				Earns/Pays	Recovery/Refund
(in millions)	2023		2022		a Return	Period Ends
Regulatory Assets(a)
AROs – nuclear and other	$	26	$	27		(d)
Accrued pension and OPEB(c)	129		119			(g)
Vacation accrual	13		12			2024
Derivatives – natural gas supply contracts(f)	147		168
Deferred pipeline integrity costs(c)	103		93			2025
Decoupling	75		42		(e)	(b)
Tennessee ARM Deferral	20		3		(e)	(b)
Other	58		47		(e)	(b)
Total regulatory assets	571		511
Less: Current portion	161		119
Total noncurrent regulatory assets	$	410	$	392
Regulatory Liabilities(a)
Net regulatory liability related to income taxes	$	433	$	459		(b)
COR regulatory liability(c)	555		573			(d)
Other	98		66		(e)	(b)
Total regulatory liabilities	1,086		1,098
Less: Current portion	98		74
Total noncurrent regulatory liabilities	$	988	$	1,024

(a)    Regulatory assets and liabilities are excluded from rate base unless otherwise noted.

(b)    The expected recovery or refund period varies or has not been determined.

(c)    Included in rate base.

(d)    Recovery over the life of the associated assets.

(e)    Certain costs earn/pay a return.

(f)    Balance will fluctuate with changes in the market. Current contracts extend into 2031.

(g)    Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 23 for additional detail.

Schedule of Regulatory Liabilities

The following tables present the regulatory assets and liabilities recorded on Piedmont's Consolidated Balance Sheets.

	December 31,				Earns/Pays	Recovery/Refund
(in millions)	2023		2022		a Return	Period Ends
Regulatory Assets(a)
AROs – nuclear and other	$	26	$	27		(d)
Accrued pension and OPEB(c)	129		119			(g)
Vacation accrual	13		12			2024
Derivatives – natural gas supply contracts(f)	147		168
Deferred pipeline integrity costs(c)	103		93			2025
Decoupling	75		42		(e)	(b)
Tennessee ARM Deferral	20		3		(e)	(b)
Other	58		47		(e)	(b)
Total regulatory assets	571		511
Less: Current portion	161		119
Total noncurrent regulatory assets	$	410	$	392
Regulatory Liabilities(a)
Net regulatory liability related to income taxes	$	433	$	459		(b)
COR regulatory liability(c)	555		573			(d)
Other	98		66		(e)	(b)
Total regulatory liabilities	1,086		1,098
Less: Current portion	98		74
Total noncurrent regulatory liabilities	$	988	$	1,024

(a)    Regulatory assets and liabilities are excluded from rate base unless otherwise noted.

(b)    The expected recovery or refund period varies or has not been determined.

(c)    Included in rate base.

(d)    Recovery over the life of the associated assets.

(e)    Certain costs earn/pay a return.

(f)    Balance will fluctuate with changes in the market. Current contracts extend into 2031.

(g)    Recovered primarily over the average remaining service periods or life expectancies of employees covered by the benefit plans. See Note 23 for additional detail.