Property And Plant, Net (Tables)

12 Months Ended

Dec. 31, 2022

Property, Plant and Equipment [Abstract]

Schedule Of Property And Plant, Net

The following table presents components of “Property, plant, and equipment, net” at December 31, 2022 and 2021:

	Ameren Missouri		Ameren Illinois		Other		Ameren
2022
Property, plant, and equipment at original cost(a):
Electric generation:
Coal(b)(c)	$	3,454	$	—	$	—	$	3,454
Natural gas	961		—		—		961
Nuclear	5,725		—		—		5,725
Renewable(d)	1,957		11		—		1,968
Electric distribution	7,993		7,351		—		15,344
Electric transmission	1,884		4,617		1,815		8,316
Natural gas	640		3,883		—		4,523
Other(e)	1,904		1,395		249		3,548
	24,518		17,257		2,064		43,839
Less: Accumulated depreciation and amortization	9,682		4,418		365		14,465
	14,836		12,839		1,699		29,374
Construction work in progress:
Nuclear fuel in process	108		—		—		108
Other	598		514		86		1,198
Plant to be abandoned, net(f)	582		—		—		582
Property, plant, and equipment, net	$	16,124	$	13,353	$	1,785	$	31,262
2021
Property, plant, and equipment at original cost(a):
Electric generation:
Coal(b)(c)	$	3,955	$	—	$	—	$	3,955
Natural gas	1,105		—		—		1,105
Nuclear	5,615		—		—		5,615
Renewable(d)	1,889		—		—		1,889
Electric distribution	7,286		7,017		—		14,303
Electric transmission	1,628		4,105		1,800		7,533
Natural gas	607		3,586		—		4,193
Other(e)	1,584		1,183		242		3,009
	23,669		15,891		2,042		41,602
Less: Accumulated depreciation and amortization	9,784		4,100		330		14,214
	13,885		11,791		1,712		27,388
Construction work in progress:
Nuclear fuel in process	133		—		—		133
Other	674		432		30		1,136
Plant to be abandoned, net(f)	604		—		—		604
Property, plant, and equipment, net	$	15,296	$	12,223	$	1,742	$	29,261

(a)The estimated lives for each asset group are as follows: 5 to 72 years for electric generation, excluding Ameren Missouri’s hydroelectric generating assets, which have useful lives of up to 150 years; 20 to 80 years for electric distribution; 50 to 75 years for electric transmission; 20 to 80 years for natural gas; and 2 to 55 years for other.

(b)Includes $29 million of oil-fired generation at December 31, 2022 and 2021.

(c)Original cost amounts include two CTs that had related financing obligations. The gross cumulative plant asset values related to outstanding financing obligations as of December 31, 2022 and 2021, was $125 million and $243 million, respectively. The related accumulated depreciation was $54 million and $105 million. The financing obligation for the Peno Creek CT Energy Center was settled in December 2022, while the financing obligation for the Audrain CT Energy Center was settled in January 2023. See Note 5 – Long-term Debt and Equity Financings for additional information on these agreements.

(d)Renewable includes hydroelectric, wind, solar, and methane gas generation facilities.

(e)Other property, plant, and equipment includes assets used to support electric and natural gas services.

(f)Represents the net book value of the Rush Island Energy Center and related construction work in progress as Ameren Missouri expects to retire the energy center significantly in advance of its previously expected useful life and in the near term. See Plant to be Abandoned, Net under Note 1 – Summary of Significant Accounting Policies and NSR and Clean Air Act Litigation under Note 14 – Commitments and Contingencies for additional information on the planned accelerated retirement of the Rush Island Energy Center.

Schedule of Capitalized Software

Capitalized software costs are classified within “Property, Plant, and Equipment, Net” on the balance sheet and are amortized on a straight-line basis over the expected period of benefit, ranging from 2 to 15 years. The following table presents the amortization, gross carrying value, and related accumulated amortization of capitalized software by year:

	Amortization Expense						Gross Carrying Value				Accumulated Amortization
	2022		2021		2020		2022		2021		2022		2021
Ameren	$	159	$	125	$	93	$	1,443	$	1,199	$	(914)	$	(757)
Ameren Missouri	85		66		44		613		523		(339)		(255)
Ameren Illinois	69		53		45		601		452		(360)		(291)

Schedule of Capitalized Software, Future Amortization Expense

Annual amortization expense for capitalized software placed in service as of December 31, 2022, is estimated to be as follows:

	2023		2024		2025		2026		2027
Ameren	$	170	$	131	$	83	$	51	$	30
Ameren Missouri	91		71		46		26		15
Ameren Illinois	74		56		35		24		15