Asset Retirement Obligations

12 Months Ended

Dec. 31, 2020

Asset Retirement Obligation Disclosure [Abstract]

Our utilities have recorded AROs primarily for the removal of natural gas distribution mains and service pipes (including asbestos and PCBs); asbestos abatement at certain generation and substation facilities, office buildings, and service centers; the removal and dismantlement of biomass and hydro generation facilities; the dismantling of wind generation projects; the dismantling of solar generation projects; the disposal of PCB-contaminated transformers; the closure of coal combustion residual landfills at certain generation facilities; and the removal of above ground storage tanks. Regulatory assets and liabilities are established by our utilities to record the differences between ongoing expense recognition under the ARO accounting rules and the rate-making practices for retirement costs authorized by the applicable regulators.

WECI has also recorded AROs for the dismantling of our non-utility wind generation projects.

On our balance sheets, AROs are recorded within other long-term liabilities. The following table shows changes to our AROs during the years ended December 31:


(in millions)	2020			2019			2018
Balance as of January 1	$	483.5		$	461.4		$	573.7
Accretion	20.7			22.1			28.0
Additions and revisions to estimated cash flows	39.7		(1)	39.1		(2)	(104.5)		(3)
Liabilities settled	(30.4)			(39.1)			(35.8)
Balance as of December 31	$	513.5		$	483.5		$	461.4

(1) AROs increased $39.3 million in 2020, primarily due to new natural gas distribution lines being placed into service at PGL. Also in 2020, AROs increased by $8.5 million as a result of AROs being recorded for the legal requirement to dismantle, at retirement, the Two Creeks solar generation project. AROs decreased $9.2 million due to revisions made to estimated cash flows for the abatement of asbestos at WE.

(2) AROs increased $40.1 million in 2019, primarily due to new natural gas distribution lines being placed into service at PGL. Also in 2019, AROs increased $10.7 million as a result of AROs being recorded for the legal requirement to dismantle, at retirement, certain non-utility wind generation projects. AROs decreased $7.3 million due to revisions made to estimated cash flows for the abatement of asbestos at WE.

(3) AROs decreased $127.3 million in 2018 due to revisions made to estimated cash flows primarily for changes in the cost to retire natural gas distribution pipe at PGL. Also in 2018, AROs increased $10.7 million as a result of revisions made to estimated cash flows for the abatement of asbestos at WPS's Pulliam power plant, and a $10.9 million ARO was recorded for the legal requirement to dismantle, at retirement, certain wind generation projects.