Regulatory Assets and Liabilities

12 Months Ended

Dec. 31, 2023

Regulatory Assets and Liabilities Disclosure [Abstract]

Regulatory Assets and Liabilities

Regulatory assets and liabilities are created for amounts that regulators may allow to be collected or may require to be paid back to customers in future electric and natural gas rates. PSCo would be required to recognize the write-off of regulatory assets and liabilities in net income or other comprehensive income if changes in the utility industry no longer allow for the application of regulatory accounting guidance under GAAP.

Components of regulatory assets:

(Millions of Dollars)	See Note(s)	Remaining Amortization Period	Dec. 31, 2023				Dec. 31, 2022
Regulatory Assets			Current		Noncurrent		Current		Noncurrent
Pension and retiree medical obligations	9	Various	$	2	$	396	$	3	$	367
Net AROs (a)	1, 10	Various	—		236		—		212
Depreciation differences		One to 10 years	16		184		16		187
Recoverable deferred taxes on AFUDC		Plant lives	—		135		—		119
Excess deferred taxes — TCJA	7	Various	—		55		2		54
Environmental remediation costs		Various	—		44		6		26
Conservation programs (b)	1	One to two years	12		33		8		16
Revenue decoupling		Various	—		31		—		—
Gas pipeline inspection costs		One to two years	3		25		—		13
Deferred natural gas, electric, steam energy/fuel costs		One to three years	221		22		312		200
Purchased power contract costs		Term of related contract	4		20		3		16
Grid modernization costs		Two years	15		14		14		22
Property tax		Various	3		7		8		2
Other		Various	28		65		39		43
Total regulatory assets			$	304	$	1,267	$	411	$	1,277

(a)Includes amounts recorded for future recovery of AROs.

(b)Includes costs for conservation programs, as well as incentives allowed in certain jurisdictions.

Components of regulatory liabilities:

(Millions of Dollars)	See Note(s)	Remaining Amortization Period	Dec. 31, 2023				Dec. 31, 2022
Regulatory Liabilities			Current		Noncurrent		Current		Noncurrent
Deferred income tax adjustments and TCJA refunds (a)	7	Various	$	2	$	1,260	$	2	$	1,298
Plant removal costs	1, 10	Various	—		769		—		705
Effects of regulation on employee benefit costs (b)		Various	—		234		—		227
Renewable resources and environmental initiatives		Various	—		152		—		141
Revenue decoupling		Various	—		63		—		55
ITC deferrals	1	Various	1		44		1		41
Deferred natural gas, electric, steam energy/fuel costs		Less than one year	34		—		3		—
Conservation programs	1	Less than one year	9		—		19		—
Formula rates		One to two years	8		—		16		—
Other		Various	16		40		18		22
Total regulatory liabilities			$	70	$	2,562	$	59	$	2,489

(a)Includes the revaluation of recoverable/regulated plant accumulated deferred income taxes and revaluation impact of non-plant accumulated deferred income taxes due to the TCJA.

(b)Includes regulatory amortization and certain 2018 TCJA benefits approved by the CPUC to offset the prepaid pension asset.

PSCo’s regulatory assets not earning a return include past expenditures of $416 million and $538 million at Dec. 31, 2023 and 2022, respectively, which predominately relate to purchased natural gas and electric energy costs (including certain costs related to Winter Storm Uri), sales true-up and revenue decoupling and various renewable resources/environmental initiatives. Additionally, the unfunded portion of pension and retiree medical obligations and net AROs (i.e. deferrals for which cash has not been disbursed) do not earn a return.