Regulatory Assets and Liabilities

12 Months Ended

Dec. 31, 2021

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. NSP-Wisconsin 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, 2021				Dec. 31, 2020
Regulatory Assets			Current		Noncurrent		Current		Noncurrent
Environmental remediation costs	1, 10	Various	$	13	$	79	$	13	$	94
Pension and retiree medical obligations	9	Various	4		55		4		67
Deferred natural gas and electric energy/fuel costs	7	One to two years	2		29		—		—
State commission adjustments		Plant lives	1		21		1		20
Recoverable deferred taxes on AFUDC		Plant lives	—		19		—		18
Net AROs (a)	1, 10	Various	—		10		—		6
Losses on reacquired debt		Term of related debt	—		2		—		2
Other		Various	1		10		1		8
Total regulatory assets			$	21	$	225	$	19	$	215

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

Components of regulatory liabilities:

(Millions of Dollars)	See Note(s)	Remaining Amortization Period	Dec. 31, 2021				Dec. 31, 2020
Regulatory Liabilities			Current		Noncurrent		Current		Noncurrent
Plant removal costs	1, 10	Various	$	—	$	201	$	—	$	184
Deferred income tax adjustments and TCJA refunds (a)	7	Various	—		152		—		161
United States Department of Energy Settlement		Various	—		14		12		—
Deferred natural gas and electric energy/fuel costs		Less than one year	3		—		17		1
Other		Various	1		5		2		4
Total regulatory liabilities			$	4	$	372	$	31	$	350

(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.

At Dec. 31, 2021 and 2020, NSP-Wisconsin had no regulatory assets of past expenditures that were not eligible to earn a return.