Plant, Property, and Equipment

12 Months Ended

Dec. 31, 2024

Public Utility, Property, Plant and Equipment [Line Items]

Plant, Property, and Equipment

Plant, Property, and Equipment

Presented in the following table are details of CMS Energy’s and Consumers’ plant, property, and equipment:

In Millions, Except as Noted
December 31	Estimated Depreciable Life in Years	2024			2023
CMS Energy, including Consumers
Plant, property, and equipment, gross
Consumers	3 – 125		$	33,434		$	31,723
NorthStar Clean Energy
Independent power production1	3 – 40		1,452			1,387
Assets under finance leases2			45			24
Other	3 – 5		1			1
Plant, property, and equipment, gross			$	34,932		$	33,135
Construction work in progress			2,098			944
Accumulated depreciation and amortization			(9,569)			(9,007)
Total plant, property, and equipment3			$	27,461		$	25,072
Consumers
Plant, property, and equipment, gross
Electric
Generation	15 – 125		$	6,576		$	6,511
Distribution	15 – 75		12,135			11,339
Other	5 – 55		1,307			1,355
Assets under finance leases2			119			97
Gas
Distribution	20 – 85		7,942			7,452
Transmission	17 – 75		3,081			2,806
Underground storage facilities4	29 – 75		1,405			1,295
Other	5 – 55		828			815
Assets under finance leases2			12			15
Other non-utility property	3 – 51		29			38
Plant, property, and equipment, gross			$	33,434		$	31,723
Construction work in progress			1,766			845
Accumulated depreciation and amortization			(9,310)			(8,796)
Total plant, property, and equipment2			$	25,890		$	23,772

1A portion of independent power production assets are leased to others under operating leases. For information regarding CMS Energy’s operating leases of owned assets, see Note 8, Leases.

2For information regarding the amortization terms of CMS Energy’s and Consumers’ assets under finance leases, see Note 8, Leases.

3Consumers’ plant additions were $2.1 billion for the year ended December 31, 2024 and $3.1 billion for the year ended December 31, 2023. Consumers’ plant retirements were $390 million for the year ended December 31, 2024 and $856 million for the year ended December 31, 2023.

4Underground storage includes base natural gas of $26 million at December 31, 2024 and 2023. Base natural gas is not subject to depreciation.

Intangible Assets: Included in net plant, property, and equipment are intangible assets. Presented in the following table are details about Consumers’ intangible assets:

In Millions, Except as Noted
Description	Amortization Life in Years	December 31, 2024						December 31, 2023
		Gross Cost1			Accumulated Amortization			Gross Cost1			Accumulated Amortization
Consumers
Software development	3 – 15		$	679		$	481		$	772		$	543
Rights of way	50 – 85		253			68			229			64
Franchises and consents	5 – 50		16			11			16			11
Leasehold improvements	various2		13			7			11			7
Other intangibles	various		28			16			24			15
Total			$	989		$	583		$	1,052		$	640

1Consumers’ intangible asset additions were $90 million for the year ended December 31, 2024 and $80 million for the year ended December 31, 2023. Consumers’ intangible asset retirements were $153 million for the year ended December 31, 2024 and $142 million for the year ended December 31, 2023.

2Leasehold improvements are amortized over the life of the lease, which may change whenever the lease is renewed or extended.

Capitalization: CMS Energy and Consumers record plant, property, and equipment at original cost when placed into service. The cost includes labor, material, applicable taxes, overhead such as pension and other benefits, and AFUDC, if applicable. Consumers’ plant, property, and equipment is generally recoverable through its general ratemaking process.

With the exception of utility property for which the remaining book value has been securitized, mothballed utility property stays in rate base and continues to be depreciated at the same rate as before the mothball period. When utility property is retired or otherwise disposed of in the ordinary course of business, Consumers records the original cost to accumulated depreciation, along with associated cost of removal, net of salvage. CMS Energy and Consumers recognize gains or losses on the retirement or disposal of non‑regulated assets in income. Consumers records cost of removal collected from customers, but not spent, as a regulatory liability.

Software: CMS Energy and Consumers capitalize the costs to purchase and develop internal-use computer software. These costs are expensed evenly over the estimated useful life of the internal-use computer software. If computer software is integral to computer hardware, then its cost is capitalized and depreciated with the hardware.

AFUDC: Consumers capitalizes AFUDC on regulated major construction projects. AFUDC represents the estimated cost of debt and authorized return-on-equity funds used to finance construction additions. Consumers records the offsetting credit as a reduction of interest for the amount representing the borrowed funds component and as other income for the equity funds component on the consolidated statements of income. When construction is completed and the property is placed in service, Consumers

depreciates and recovers the capitalized AFUDC from customers over the life of the related asset. Presented in the following table are Consumers’ average AFUDC capitalization rates:

Years Ended December 31	2024		2023		2022
Electric	6.9	%	6.5	%	6.2	%
Gas	5.8		5.8		5.6

Assets Under Finance Leases: Presented in the following table are further details about changes in CMS Energy’s and Consumers’ assets under finance leases:

In Millions
Years Ended December 31	2024			2023
CMS Energy, including Consumers
Balance at beginning of period		$	136		$	170
Additions		55			—
Net retirements and other adjustments		(15)			(34)
Balance at end of period		$	176		$	136
Consumers
Balance at beginning of period		$	112		$	146
Additions		34			—
Net retirements and other adjustments		(15)			(34)
Balance at end of period		$	131		$	112

Assets under finance leases are presented as gross amounts. CMS Energy’s, including Consumers’, accumulated amortization of assets under finance leases was $57 million at December 31, 2024 and $65 million at December 31, 2023. Consumers’ accumulated amortization of assets under finance leases was $55 million at December 31, 2024 and $64 million at December 31, 2023.

Depreciation and Amortization: Presented in the following table are further details about CMS Energy’s and Consumers’ accumulated depreciation and amortization:

In Millions
Years Ended December 31	2024			2023
CMS Energy, including Consumers
Utility plant assets		$	9,307		$	8,790
Non-utility plant assets		262			217
Consumers
Utility plant assets		$	9,307		$	8,790
Non-utility plant assets		3			6

Consumers depreciates utility property on an asset-group basis, in which it applies a single MPSC-approved depreciation rate to the gross investment in a particular class of property within the electric and

gas segments. Consumers performs depreciation studies periodically to determine appropriate group lives. Presented in the following table are the composite depreciation rates for Consumers’ segment properties:

Years Ended December 31	2024		2023		2022
Electric utility property	3.6	%	3.8	%	3.7	%
Gas utility property	2.5		2.8		2.9
Other property	7.1		7.8		8.9

CMS Energy and Consumers record property repairs and minor property replacement as maintenance expense. CMS Energy and Consumers record planned major maintenance activities as operating expense unless the cost represents the acquisition of additional long-lived assets or the replacement of an existing long-lived asset.

Presented in the following table are the components of CMS Energy’s and Consumers’ depreciation and amortization expense:

In Millions
Years Ended December 31	2024			2023			2022
CMS Energy, including Consumers
Depreciation expense – plant, property, and equipment		$	1,041		$	1,050		$	990
Amortization expense
Software		81			92			103
Other intangible assets		5			5			5
Other regulatory assets		2			—			—
Securitized regulatory assets		111			33			28
Total depreciation and amortization expense		$	1,240		$	1,180		$	1,126
Consumers
Depreciation expense – plant, property, and equipment		$	992		$	1,007		$	952
Amortization expense
Software		81			92			103
Other intangible assets		5			5			5
Other regulatory assets		2			—			—
Securitized regulatory assets		111			33			28
Total depreciation and amortization expense		$	1,191		$	1,137		$	1,088

Presented in the following table is Consumers’ estimated amortization expense on intangible assets for each of the next five years:

In Millions
	2025			2026			2027			2028			2029
Consumers
Intangible asset amortization expense		$	94		$	90		$	83		$	77		$	75

Jointly Owned Regulated Utility Facilities

Presented in the following table are Consumers’ investments in jointly owned regulated utility facilities at December 31, 2024:

In Millions, Except Ownership Share
	J.H. Campbell Unit 3				Ludington				Other
Ownership share		93.3		%		51.0		%		various
Utility plant in service		$	1,725			$	621			$	445
Accumulated provision for depreciation		(856)				(242)				(95)
Plant under construction		—				13				29
Net investment		$	869			$	392			$	379

Consumers includes its share of the direct expenses of the jointly owned plants in operating expenses. Consumers shares operation, maintenance, and other expenses of these jointly owned utility facilities in proportion to each participant’s undivided ownership interest. Consumers is required to provide only its share of financing for the jointly owned utility facilities.

Consumers plans to retire the J.H. Campbell coal-fueled generating units and, in 2022, removed an amount representing the projected remaining book value of the electric generating units upon their retirement from total plant, property, and equipment and recorded it as a regulatory asset on its consolidated balance sheets. For additional details, see Note 2, Regulatory Matters.

Consumers and DTE Electric are engaged in ongoing litigation with TAES and Toshiba related to TAES’ incomplete, defective, and nonconforming work during a major overhaul and upgrade of Ludington. For additional details on this dispute, see Note 3, Contingencies and Commitments—Ludington Overhaul Contract Dispute.

Consumers Energy Company

Public Utility, Property, Plant and Equipment [Line Items]

Plant, Property, and Equipment

Plant, Property, and Equipment

Presented in the following table are details of CMS Energy’s and Consumers’ plant, property, and equipment:

In Millions, Except as Noted
December 31	Estimated Depreciable Life in Years	2024			2023
CMS Energy, including Consumers
Plant, property, and equipment, gross
Consumers	3 – 125		$	33,434		$	31,723
NorthStar Clean Energy
Independent power production1	3 – 40		1,452			1,387
Assets under finance leases2			45			24
Other	3 – 5		1			1
Plant, property, and equipment, gross			$	34,932		$	33,135
Construction work in progress			2,098			944
Accumulated depreciation and amortization			(9,569)			(9,007)
Total plant, property, and equipment3			$	27,461		$	25,072
Consumers
Plant, property, and equipment, gross
Electric
Generation	15 – 125		$	6,576		$	6,511
Distribution	15 – 75		12,135			11,339
Other	5 – 55		1,307			1,355
Assets under finance leases2			119			97
Gas
Distribution	20 – 85		7,942			7,452
Transmission	17 – 75		3,081			2,806
Underground storage facilities4	29 – 75		1,405			1,295
Other	5 – 55		828			815
Assets under finance leases2			12			15
Other non-utility property	3 – 51		29			38
Plant, property, and equipment, gross			$	33,434		$	31,723
Construction work in progress			1,766			845
Accumulated depreciation and amortization			(9,310)			(8,796)
Total plant, property, and equipment2			$	25,890		$	23,772

1A portion of independent power production assets are leased to others under operating leases. For information regarding CMS Energy’s operating leases of owned assets, see Note 8, Leases.

2For information regarding the amortization terms of CMS Energy’s and Consumers’ assets under finance leases, see Note 8, Leases.

3Consumers’ plant additions were $2.1 billion for the year ended December 31, 2024 and $3.1 billion for the year ended December 31, 2023. Consumers’ plant retirements were $390 million for the year ended December 31, 2024 and $856 million for the year ended December 31, 2023.

4Underground storage includes base natural gas of $26 million at December 31, 2024 and 2023. Base natural gas is not subject to depreciation.

Intangible Assets: Included in net plant, property, and equipment are intangible assets. Presented in the following table are details about Consumers’ intangible assets:

In Millions, Except as Noted
Description	Amortization Life in Years	December 31, 2024						December 31, 2023
		Gross Cost1			Accumulated Amortization			Gross Cost1			Accumulated Amortization
Consumers
Software development	3 – 15		$	679		$	481		$	772		$	543
Rights of way	50 – 85		253			68			229			64
Franchises and consents	5 – 50		16			11			16			11
Leasehold improvements	various2		13			7			11			7
Other intangibles	various		28			16			24			15
Total			$	989		$	583		$	1,052		$	640

1Consumers’ intangible asset additions were $90 million for the year ended December 31, 2024 and $80 million for the year ended December 31, 2023. Consumers’ intangible asset retirements were $153 million for the year ended December 31, 2024 and $142 million for the year ended December 31, 2023.

2Leasehold improvements are amortized over the life of the lease, which may change whenever the lease is renewed or extended.

Capitalization: CMS Energy and Consumers record plant, property, and equipment at original cost when placed into service. The cost includes labor, material, applicable taxes, overhead such as pension and other benefits, and AFUDC, if applicable. Consumers’ plant, property, and equipment is generally recoverable through its general ratemaking process.

With the exception of utility property for which the remaining book value has been securitized, mothballed utility property stays in rate base and continues to be depreciated at the same rate as before the mothball period. When utility property is retired or otherwise disposed of in the ordinary course of business, Consumers records the original cost to accumulated depreciation, along with associated cost of removal, net of salvage. CMS Energy and Consumers recognize gains or losses on the retirement or disposal of non‑regulated assets in income. Consumers records cost of removal collected from customers, but not spent, as a regulatory liability.

Software: CMS Energy and Consumers capitalize the costs to purchase and develop internal-use computer software. These costs are expensed evenly over the estimated useful life of the internal-use computer software. If computer software is integral to computer hardware, then its cost is capitalized and depreciated with the hardware.

AFUDC: Consumers capitalizes AFUDC on regulated major construction projects. AFUDC represents the estimated cost of debt and authorized return-on-equity funds used to finance construction additions. Consumers records the offsetting credit as a reduction of interest for the amount representing the borrowed funds component and as other income for the equity funds component on the consolidated statements of income. When construction is completed and the property is placed in service, Consumers

depreciates and recovers the capitalized AFUDC from customers over the life of the related asset. Presented in the following table are Consumers’ average AFUDC capitalization rates:

Years Ended December 31	2024		2023		2022
Electric	6.9	%	6.5	%	6.2	%
Gas	5.8		5.8		5.6

Assets Under Finance Leases: Presented in the following table are further details about changes in CMS Energy’s and Consumers’ assets under finance leases:

In Millions
Years Ended December 31	2024			2023
CMS Energy, including Consumers
Balance at beginning of period		$	136		$	170
Additions		55			—
Net retirements and other adjustments		(15)			(34)
Balance at end of period		$	176		$	136
Consumers
Balance at beginning of period		$	112		$	146
Additions		34			—
Net retirements and other adjustments		(15)			(34)
Balance at end of period		$	131		$	112

Assets under finance leases are presented as gross amounts. CMS Energy’s, including Consumers’, accumulated amortization of assets under finance leases was $57 million at December 31, 2024 and $65 million at December 31, 2023. Consumers’ accumulated amortization of assets under finance leases was $55 million at December 31, 2024 and $64 million at December 31, 2023.

Depreciation and Amortization: Presented in the following table are further details about CMS Energy’s and Consumers’ accumulated depreciation and amortization:

In Millions
Years Ended December 31	2024			2023
CMS Energy, including Consumers
Utility plant assets		$	9,307		$	8,790
Non-utility plant assets		262			217
Consumers
Utility plant assets		$	9,307		$	8,790
Non-utility plant assets		3			6

Consumers depreciates utility property on an asset-group basis, in which it applies a single MPSC-approved depreciation rate to the gross investment in a particular class of property within the electric and

gas segments. Consumers performs depreciation studies periodically to determine appropriate group lives. Presented in the following table are the composite depreciation rates for Consumers’ segment properties:

Years Ended December 31	2024		2023		2022
Electric utility property	3.6	%	3.8	%	3.7	%
Gas utility property	2.5		2.8		2.9
Other property	7.1		7.8		8.9

CMS Energy and Consumers record property repairs and minor property replacement as maintenance expense. CMS Energy and Consumers record planned major maintenance activities as operating expense unless the cost represents the acquisition of additional long-lived assets or the replacement of an existing long-lived asset.

Presented in the following table are the components of CMS Energy’s and Consumers’ depreciation and amortization expense:

In Millions
Years Ended December 31	2024			2023			2022
CMS Energy, including Consumers
Depreciation expense – plant, property, and equipment		$	1,041		$	1,050		$	990
Amortization expense
Software		81			92			103
Other intangible assets		5			5			5
Other regulatory assets		2			—			—
Securitized regulatory assets		111			33			28
Total depreciation and amortization expense		$	1,240		$	1,180		$	1,126
Consumers
Depreciation expense – plant, property, and equipment		$	992		$	1,007		$	952
Amortization expense
Software		81			92			103
Other intangible assets		5			5			5
Other regulatory assets		2			—			—
Securitized regulatory assets		111			33			28
Total depreciation and amortization expense		$	1,191		$	1,137		$	1,088

Presented in the following table is Consumers’ estimated amortization expense on intangible assets for each of the next five years:

In Millions
	2025			2026			2027			2028			2029
Consumers
Intangible asset amortization expense		$	94		$	90		$	83		$	77		$	75

Jointly Owned Regulated Utility Facilities

Presented in the following table are Consumers’ investments in jointly owned regulated utility facilities at December 31, 2024:

In Millions, Except Ownership Share
	J.H. Campbell Unit 3				Ludington				Other
Ownership share		93.3		%		51.0		%		various
Utility plant in service		$	1,725			$	621			$	445
Accumulated provision for depreciation		(856)				(242)				(95)
Plant under construction		—				13				29
Net investment		$	869			$	392			$	379

Consumers includes its share of the direct expenses of the jointly owned plants in operating expenses. Consumers shares operation, maintenance, and other expenses of these jointly owned utility facilities in proportion to each participant’s undivided ownership interest. Consumers is required to provide only its share of financing for the jointly owned utility facilities.

Consumers plans to retire the J.H. Campbell coal-fueled generating units and, in 2022, removed an amount representing the projected remaining book value of the electric generating units upon their retirement from total plant, property, and equipment and recorded it as a regulatory asset on its consolidated balance sheets. For additional details, see Note 2, Regulatory Matters.

Consumers and DTE Electric are engaged in ongoing litigation with TAES and Toshiba related to TAES’ incomplete, defective, and nonconforming work during a major overhaul and upgrade of Ludington. For additional details on this dispute, see Note 3, Contingencies and Commitments—Ludington Overhaul Contract Dispute.