Regulatory Assets and Liabilities (Tables)

12 Months Ended

Dec. 31, 2023

Regulatory Assets and Liabilities Disclosure [Abstract]

Schedule of regulatory assets

The following regulatory assets were reflected on our balance sheets as of December 31:

(in millions)	2023		2022		See Note
Regulatory assets (1) (2)
Pension and OPEB costs (3)	$	731.7	$	714.3	20, 26
Plant retirement related items	646.2		688.6
Environmental remediation costs (4)	596.8		610.7		24
Income tax related items	449.9		461.9		16
AROs	162.0		169.7		1(l), 9
Derivatives	130.3		133.8		1(s)
Uncollectible expense	127.7		69.3		5
SSR (5)	113.2		123.5
Securitization	85.9		92.4		23
Bluewater (6)	45.3		20.9
Energy efficiency programs (7)	33.9		33.9
Energy costs recoverable through rate adjustments	3.2		26.9		1(d)
MERC extraordinary natural gas costs (8)	0.8		35.1		26
Other, net	147.8		125.9
Total regulatory assets	$	3,274.7	$	3,306.9
Balance sheet presentation
Other current assets	$	24.9	$	42.3
Regulatory assets	3,249.8		3,264.6
Total regulatory assets	$	3,274.7	$	3,306.9

(1)    Based on prior and current rate treatment, we believe it is probable that our utilities will continue to recover from customers the regulatory assets in this table. In accordance with GAAP, our regulatory assets do not include the allowance for ROE that is capitalized for regulatory purposes. This allowance was $26.7 million and $27.3 million at December 31, 2023 and 2022, respectively.

(2)    As of December 31, 2023, we had $254.6 million of regulatory assets not earning a return, $5.4 million of regulatory assets earning a return based on short-term interest rates, $129.7 million of regulatory assets earning a return based on long-term interest rates, and $2.5 million of regulatory assets earning a return based on the applicable utility's ROE. The regulatory assets not earning a return primarily relate to certain environmental remediation costs, uncollectible expense, our invested capital tax rider, decoupling mechanisms, unamortized loss on reacquired debt, and rate case costs. The other regulatory assets in the table either earn a return at the applicable utility's weighted average cost of capital or the cash has not yet been expended, in which case the regulatory assets are offset by liabilities.

(3)    Primarily represents the unrecognized future pension and OPEB costs related to our defined benefit pension and OPEB plans. We are authorized recovery of these regulatory assets over the average remaining service life of each plan.

(4)    As of December 31, 2023, we had made cash expenditures of $133.1 million related to these environmental remediation costs. The remaining $463.7 million represents our estimated future cash expenditures.

(5)    This regulatory asset relates to WE's 2014 announcement to retire the PIPP. Despite WE's intent to retire the PIPP, MISO designated the PIPP as a SSR, which meant the PIPP's operation was necessary for reliability, and the plant could not be shut down until new generation or transmission facilities were built. In December 2014, the PSCW authorized escrow accounting for WE's SSR revenues because of the fluctuations in the actual revenues WE received under the PIPP SSR agreements. The rate order WE received from the PSCW in December 2019 authorized recovery of this SSR regulatory asset over a 15-year period that began on January 1, 2020.

(6)    Primarily relates to costs associated with the long-term service agreements our Wisconsin utilities have with Bluewater for natural gas storage services. The PSCW has approved escrow accounting for these costs. As a result, our Wisconsin utilities defer as a regulatory asset or liability the difference between actual storage costs and those included in rates until recovery or refund is authorized in a future rate proceeding.

(7)    Represents amounts recoverable from customers related to programs at the utilities designed to meet energy efficiency standards.

(8)    Represents the extraordinary natural gas costs MERC incurred during February 2021 that were substantially recovered over 27 months, beginning in September 2021. See Note 26, Regulatory Environment, for more information on our recovery efforts associated with these costs.

Schedule of regulatory liabilities

The following regulatory liabilities were reflected on our balance sheets as of December 31:

(in millions)	2023		2022		See Note
Regulatory liabilities
Income tax related items	$	1,901.8	$	1,956.6	16
Removal costs (1)	1,329.9		1,260.9
Pension and OPEB benefits (2)	299.2		340.5		20, 26
Energy costs refundable through rate adjustments	72.4		53.4		1(d)
Electric transmission costs (3)	30.3		0.4
Uncollectible expense	21.2		24.0		5
Derivatives	19.2		76.7		1(s)
Energy efficiency programs (4)	17.2		10.4
Decoupling	—		20.2		1(d)
Other, net	54.0		48.8
Total regulatory liabilities	$	3,745.2	$	3,791.9
Balance sheet presentation
Other current liabilities	$	47.5	$	56.4
Regulatory liabilities	3,697.7		3,735.5
Total regulatory liabilities	$	3,745.2	$	3,791.9

(1)    Represents amounts collected from customers to cover the future cost of property, plant, and equipment removals that are not legally required. Legal obligations related to the removal of property, plant, and equipment are recorded as AROs. See Note 9, Asset Retirement Obligations, for more information on our legal obligations.

(2)    Primarily represents the unrecognized future pension and OPEB benefits related to our defined benefit pension and OPEB plans. We will amortize these regulatory liabilities into net periodic benefit cost over the average remaining service life of each plan.

(3)    In accordance with the PSCW's approval of escrow accounting for ATC and MISO network transmission expenses for our Wisconsin electric utilities, WE and WPS defer as a regulatory asset or liability the difference between actual transmission costs and those included in rates until recovery or refund is authorized in a future rate proceeding.

(4)    Represents amounts refundable to customers related to programs at the utilities designed to meet energy efficiency standards.