Asset Retirement Obligations (Tables)

9 Months Ended

Sep. 30, 2020

Asset Retirement Obligation [Abstract]

Schedule of Asset Retirement Obligations

The following table presents the AROs recorded on the Condensed Consolidated Balance Sheets.

	September 30, 2020
			Duke				Duke		Duke		Duke		Duke
	Duke		Energy		Progress		Energy		Energy		Energy		Energy
(in millions)	Energy		Carolinas		Energy		Progress		Florida		Ohio		Indiana		Piedmont
Decommissioning of nuclear power facilities(a)	$	6,815	$	2,658	$	4,107	$	3,606	$	501	$	—	$	—	$	—
Closure of ash impoundments	6,458		3,049		2,172		2,150		22		51		1,186		—
Other	381		67		76		44		32		40		28		17
Total ARO	$	13,654	$	5,774	$	6,355	$	5,800	$	555	$	91	$	1,214	$	17
Less: Current portion	742		267		297		297		—		7		170		—
Total noncurrent ARO	$	12,912	$	5,507	$	6,058	$	5,503	$	555	$	84	$	1,044	$	17

(a)    Duke Energy amount includes purchase accounting adjustments related to the merger with Progress Energy.

Schedule of Change in Asset Retirement Obligation

The following table presents the change in liability associated with AROs for the Duke Energy Registrants.

				Duke						Duke			Duke			Duke			Duke
	Duke			Energy			Progress			Energy			Energy			Energy			Energy
(in millions)	Energy			Carolinas			Energy			Progress			Florida			Ohio			Indiana			Piedmont
Balance at December 31, 2019(a)	$	13,318		$	5,734		$	6,471		$	5,893		$	578		$	80		$	832		$	17
Accretion expense(b)	408			195			187			171			16			3			22			—
Liabilities settled(c)	(540		)	(151		)	(333		)	(293		)	(40		)	(1		)	(56		)	—
Liabilities incurred in the current year	17			—			—			—			—			—			—			—
Revisions in estimates of cash flows(d)	451			(4		)	30			29			1			9			416			—
Balance at September 30, 2020	$	13,654		$	5,774		$	6,355		$	5,800		$	555		$	91		$	1,214		$	17

(a) Primarily relates to decommissioning nuclear power facilities, closure of ash impoundments, asbestos removal, closure of landfills at fossil generation facilities, retirement of natural gas mains and removal of renewable energy generation assets.

(b) For the nine months ended September 30, 2020, substantially all accretion expense relates to Duke Energy's regulated operations and has been deferred in accordance with regulatory accounting treatment.

(c) Primarily relates to ash impoundment closures.

(d)

Primarily relates to increases in closure estimates for certain ash impoundments as a result of certain changes in estimates and the impact of Hoosier Environmental Council’s petition filed with the court challenging the Indiana Department of Environmental Management’s partial approval of Duke Energy Indiana’s ash pond closure plan, new closure plan approvals, as well as increased post closure maintenance, landfill and beneficiation costs. See Note 4 for more information on Hoosier Environmental Council's petition. The incremental amount recorded represents the discounted cash flows for estimated closure costs based upon the probability weightings of the potential closure methods as evaluated on a site-by-site basis.