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Plant, Property, and Equipment | 12 Months Ended
--- | ---
Dec. 31, 2018
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 |
December 31 | Estimated Depreciable Life in Years | 2018 |  | 2017 |
CMS Energy, including Consumers |  |  |  |  |  |  |
Plant, property, and equipment, gross |  |  |  |  |  |  |
Consumers | 3 | — | 125 |  | $ | 23,963 |  |  | $ | 22,318 |
Enterprises |  |  |  |  |  |  |
Independent power production | 3 | — | 35 |  | 410 |  |  | 163 |
Other | 3 | — | 5 |  | 2 |  |  | 4 |
Other | 1 | — | 7 |  | 25 |  |  | 21 |
Plant, property, and equipment, gross |  |  |  |  | $ | 24,400 |  |  | $ | 22,506 |
Construction work in progress |  |  |  |  | 763 |  |  | 765 |
Accumulated depreciation and amortization |  |  |  |  | (7,037 | ) |  | (6,510 | )
Total plant, property, and equipment |  |  |  |  | $ | 18,126 |  |  | $ | 16,761 |
Consumers |  |  |  |  |  |  |
Plant, property, and equipment, gross |  |  |  |  |  |  |
Electric |  |  |  |  |  |  |
Generation | 22 | — | 125 |  | $ | 6,305 |  |  | $ | 6,025 |
Distribution | 20 | — | 75 |  | 7,957 |  |  | 7,603 |
Transmission | 46 | — | 75 |  | 154 |  |  | 66 |
Other | 5 | — | 50 |  | 1,316 |  |  | 1,229 |
Assets under capital leases and financing obligation 1 |  |  |  |  | 295 |  |  | 298 |
Gas |  |  |  |  |  |  |
Distribution | 20 | — | 85 |  | 4,651 |  |  | 4,182 |
Transmission | 17 | — | 75 |  | 1,521 |  |  | 1,278 |
Underground storage facilities 2 | 27 | — | 75 |  | 910 |  |  | 842 |
Other | 5 | — | 50 |  | 823 |  |  | 764 |
Capital leases 1 |  |  |  |  | 14 |  |  | 14 |
Other non‑utility property | 3 | — | 51 |  | 17 |  |  | 17 |
Plant, property, and equipment, gross |  |  |  |  | $ | 23,963 |  |  | $ | 22,318 |
Construction work in progress |  |  |  |  | 756 |  |  | 753 |
Accumulated depreciation and amortization |  |  |  |  | (6,958 | ) |  | (6,441 | )
Total plant, property, and equipment 3 |  |  |  |  | $ | 17,761 |  |  | $ | 16,630 |
1 | For information regarding the amortization terms of Consumers’ assets under capital leases and financing obligation, see Note 10, Leases and Palisades Financing.
2 | Underground storage includes base natural gas of $26 million at December 31, 2018 and 2017. Base natural gas is not subject to depreciation.
3 | For the year ended December 31, 2018, Consumers’ plant additions were $1.8 billion and plant retirements were $190 million. For the year ended December 31, 2017, Consumers’ plant additions were $1.7 billion and plant retirements were $214 million.
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 rate making 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, except pollution control facilities on its fossil-fuel-fired power plants. 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 | 2018 |  | 2017 |  | 2016 |
Electric | 6.9 | % | 6.8 | % | 7.3 | %
Gas | 5.9 |  | 6.0 |  | 6.2 |
Assets Under Capital Leases and Financing Obligation: Presented in the following table are further details about changes in Consumers’ assets under capital leases and financing obligation:
In Millions |
Years Ended December 31 | 2018 |  | 2017 |
Consumers |  |  |  |
Balance at beginning of period |  | $ | 312 |  |  | $ | 310 |
Additions |  | — |  |  | 3 |
Net retirements and other adjustments |  | (3 | ) |  | (1 | )
Balance at end of period |  | $ | 309 |  |  | $ | 312 |
Assets under capital leases and financing obligation are presented as gross amounts. Accumulated amortization of assets under capital leases and financing obligation was $212 million at December 31, 2018 and $193 million at December 31, 2017 for Consumers. Depreciation and Amortization: Presented in the following table are further details about CMS Energy’s and Consumers’ accumulated depreciation and amortization:
In Millions |
December 31 | 2018 |  | 2017 |
CMS Energy, including Consumers |  |  |  |
Utility plant assets |  | $ | 6,956 |  |  | $ | 6,439 |
Non-utility plant assets |  | 81 |  |  | 71 |
Consumers |  |  |  |
Utility plant assets |  | $ | 6,956 |  |  | $ | 6,439 |
Non-utility plant assets |  | 2 |  |  | 2 |
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 | 2018 |  | 2017 |  | 2016 |
Electric utility property |  | 3.9 | % |  | 3.9 | % |  | 3.9 | %
Gas utility property |  | 2.9 |  |  | 2.9 |  |  | 2.9 |
Other property |  | 10.1 |  |  | 10.0 |  |  | 9.8 |
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 | 2018 |  | 2017 |  | 2016 |
CMS Energy, including Consumers |  |  |  |  |  |
Depreciation expense – plant, property, and equipment |  | $ | 778 |  |  | $ | 739 |  |  | $ | 687 |
Amortization expense |  |  |  |  |  |
Software |  | 127 |  |  | 114 |  |  | 96 |
Other intangible assets |  | 3 |  |  | 3 |  |  | 3 |
Securitized regulatory assets |  | 25 |  |  | 25 |  |  | 25 |
Total depreciation and amortization expense |  | $ | 933 |  |  | $ | 881 |  |  | $ | 811 |
Consumers |  |  |  |  |  |
Depreciation expense – plant, property, and equipment |  | $ | 768 |  |  | $ | 732 |  |  | $ | 680 |
Amortization expense |  |  |  |  |  |
Software |  | 125 |  |  | 112 |  |  | 95 |
Other intangible assets |  | 3 |  |  | 3 |  |  | 3 |
Securitized regulatory assets |  | 25 |  |  | 25 |  |  | 25 |
Total depreciation and amortization expense |  | $ | 921 |  |  | $ | 872 |  |  | $ | 803 |
Presented in the following table is CMS Energy’s and Consumers’ estimated amortization expense on intangible assets for each of the next five years:
In Millions |
| 2019 |  | 2020 |  | 2021 |  | 2022 |  | 2023 |
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |  |
Intangible asset amortization expense |  | $ | 132 |  |  | $ | 122 |  |  | $ | 108 |  |  | $ | 95 |  |  | $ | 74 |
Consumers |  |  |  |  |  |  |  |  |  |
Intangible asset amortization expense |  | $ | 130 |  |  | $ | 120 |  |  | $ | 106 |  |  | $ | 94 |  |  | $ | 74 |
Intangible Assets: Included in net plant, property, and equipment are intangible assets. Presented in the following table are details about CMS Energy’s and Consumers’ intangible assets:
In Millions |
|  | December 31, 2018 |  | December 31, 2017
Description | Amortization Life in Years | Gross Cost 1 |  | Accumulated Amortization |  |  | Gross Cost 1 |  | Accumulated Amortization |
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |
Software development | 1 | — | 15 |  | $ | 1,024 |  |  | $ | 603 |  |  |  | $ | 950 |  |  | $ | 481 |
Rights of way | 50 | — | 85 |  | 167 |  |  | 52 |  |  |  | 162 |  |  | 50 |
Franchises and consents | 5 | — | 30 |  | 15 |  |  | 9 |  |  |  | 14 |  |  | 8 |
Leasehold improvements | various 2 |  | 9 |  |  | 7 |  |  |  | 9 |  |  | 7 |
Other intangibles | various |  | 27 |  |  | 15 |  |  |  | 23 |  |  | 15 |
Total |  |  |  |  | $ | 1,242 |  |  | $ | 686 |  |  |  | $ | 1,158 |  |  | $ | 561 |
Consumers |  |  |  |  |  |  |  |  |  |  |  |
Software development | 3 | — | 15 |  | $ | 1,009 |  |  | $ | 595 |  |  |  | $ | 937 |  |  | $ | 475 |
Rights of way | 50 | — | 85 |  | 167 |  |  | 52 |  |  |  | 162 |  |  | 50 |
Franchises and consents | 5 | — | 30 |  | 15 |  |  | 9 |  |  |  | 14 |  |  | 8 |
Leasehold improvements | various 2 |  | 9 |  |  | 7 |  |  |  | 9 |  |  | 7 |
Other intangibles | various |  | 26 |  |  | 15 |  |  |  | 21 |  |  | 15 |
Total |  |  |  |  | $ | 1,226 |  |  | $ | 678 |  |  |  | $ | 1,143 |  |  | $ | 555 |
1 | For the year ended December 31, 2018, Consumers’ intangible asset additions were $90 million and intangible asset retirements were $7 million. For the year ended December 31, 2017, Consumers’ intangible asset additions were $100 million and there were no intangible asset retirements.
2 | Leasehold improvements are amortized over the life of the lease, which may change whenever the lease is renewed or extended.
Jointly Owned Regulated Utility Facilities Presented in the following table are Consumers’ investments in jointly owned regulated utility facilities at December 31, 2018:
In Millions, Except Ownership Share |
J.H. Campbell Unit 3 |  | Ludington |  |  | Other |
Ownership share |  | 93.3 | % |  | 51.0 | % |  | various |
Utility plant in service |  | $ | 1,688 |  |  | $ | 411 |  |  | $ | 226 |
Accumulated depreciation |  | (670 | ) |  | (155 | ) |  | (70 | )
Construction work in progress |  | 23 |  |  | 110 |  |  | 16 |
Net investment |  | $ | 1,041 |  |  | $ | 366 |  |  | $ | 172 |
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 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 |
December 31 | Estimated Depreciable Life in Years | 2018 |  | 2017 |
CMS Energy, including Consumers |  |  |  |  |  |  |
Plant, property, and equipment, gross |  |  |  |  |  |  |
Consumers | 3 | — | 125 |  | $ | 23,963 |  |  | $ | 22,318 |
Enterprises |  |  |  |  |  |  |
Independent power production | 3 | — | 35 |  | 410 |  |  | 163 |
Other | 3 | — | 5 |  | 2 |  |  | 4 |
Other | 1 | — | 7 |  | 25 |  |  | 21 |
Plant, property, and equipment, gross |  |  |  |  | $ | 24,400 |  |  | $ | 22,506 |
Construction work in progress |  |  |  |  | 763 |  |  | 765 |
Accumulated depreciation and amortization |  |  |  |  | (7,037 | ) |  | (6,510 | )
Total plant, property, and equipment |  |  |  |  | $ | 18,126 |  |  | $ | 16,761 |
Consumers |  |  |  |  |  |  |
Plant, property, and equipment, gross |  |  |  |  |  |  |
Electric |  |  |  |  |  |  |
Generation | 22 | — | 125 |  | $ | 6,305 |  |  | $ | 6,025 |
Distribution | 20 | — | 75 |  | 7,957 |  |  | 7,603 |
Transmission | 46 | — | 75 |  | 154 |  |  | 66 |
Other | 5 | — | 50 |  | 1,316 |  |  | 1,229 |
Assets under capital leases and financing obligation 1 |  |  |  |  | 295 |  |  | 298 |
Gas |  |  |  |  |  |  |
Distribution | 20 | — | 85 |  | 4,651 |  |  | 4,182 |
Transmission | 17 | — | 75 |  | 1,521 |  |  | 1,278 |
Underground storage facilities 2 | 27 | — | 75 |  | 910 |  |  | 842 |
Other | 5 | — | 50 |  | 823 |  |  | 764 |
Capital leases 1 |  |  |  |  | 14 |  |  | 14 |
Other non‑utility property | 3 | — | 51 |  | 17 |  |  | 17 |
Plant, property, and equipment, gross |  |  |  |  | $ | 23,963 |  |  | $ | 22,318 |
Construction work in progress |  |  |  |  | 756 |  |  | 753 |
Accumulated depreciation and amortization |  |  |  |  | (6,958 | ) |  | (6,441 | )
Total plant, property, and equipment 3 |  |  |  |  | $ | 17,761 |  |  | $ | 16,630 |
1 | For information regarding the amortization terms of Consumers’ assets under capital leases and financing obligation, see Note 10, Leases and Palisades Financing.
2 | Underground storage includes base natural gas of $26 million at December 31, 2018 and 2017. Base natural gas is not subject to depreciation.
3 | For the year ended December 31, 2018, Consumers’ plant additions were $1.8 billion and plant retirements were $190 million. For the year ended December 31, 2017, Consumers’ plant additions were $1.7 billion and plant retirements were $214 million.
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 rate making 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, except pollution control facilities on its fossil-fuel-fired power plants. 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 | 2018 |  | 2017 |  | 2016 |
Electric | 6.9 | % | 6.8 | % | 7.3 | %
Gas | 5.9 |  | 6.0 |  | 6.2 |
Assets Under Capital Leases and Financing Obligation: Presented in the following table are further details about changes in Consumers’ assets under capital leases and financing obligation:
In Millions |
Years Ended December 31 | 2018 |  | 2017 |
Consumers |  |  |  |
Balance at beginning of period |  | $ | 312 |  |  | $ | 310 |
Additions |  | — |  |  | 3 |
Net retirements and other adjustments |  | (3 | ) |  | (1 | )
Balance at end of period |  | $ | 309 |  |  | $ | 312 |
Assets under capital leases and financing obligation are presented as gross amounts. Accumulated amortization of assets under capital leases and financing obligation was $212 million at December 31, 2018 and $193 million at December 31, 2017 for Consumers. Depreciation and Amortization: Presented in the following table are further details about CMS Energy’s and Consumers’ accumulated depreciation and amortization:
In Millions |
December 31 | 2018 |  | 2017 |
CMS Energy, including Consumers |  |  |  |
Utility plant assets |  | $ | 6,956 |  |  | $ | 6,439 |
Non-utility plant assets |  | 81 |  |  | 71 |
Consumers |  |  |  |
Utility plant assets |  | $ | 6,956 |  |  | $ | 6,439 |
Non-utility plant assets |  | 2 |  |  | 2 |
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 | 2018 |  | 2017 |  | 2016 |
Electric utility property |  | 3.9 | % |  | 3.9 | % |  | 3.9 | %
Gas utility property |  | 2.9 |  |  | 2.9 |  |  | 2.9 |
Other property |  | 10.1 |  |  | 10.0 |  |  | 9.8 |
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 | 2018 |  | 2017 |  | 2016 |
CMS Energy, including Consumers |  |  |  |  |  |
Depreciation expense – plant, property, and equipment |  | $ | 778 |  |  | $ | 739 |  |  | $ | 687 |
Amortization expense |  |  |  |  |  |
Software |  | 127 |  |  | 114 |  |  | 96 |
Other intangible assets |  | 3 |  |  | 3 |  |  | 3 |
Securitized regulatory assets |  | 25 |  |  | 25 |  |  | 25 |
Total depreciation and amortization expense |  | $ | 933 |  |  | $ | 881 |  |  | $ | 811 |
Consumers |  |  |  |  |  |
Depreciation expense – plant, property, and equipment |  | $ | 768 |  |  | $ | 732 |  |  | $ | 680 |
Amortization expense |  |  |  |  |  |
Software |  | 125 |  |  | 112 |  |  | 95 |
Other intangible assets |  | 3 |  |  | 3 |  |  | 3 |
Securitized regulatory assets |  | 25 |  |  | 25 |  |  | 25 |
Total depreciation and amortization expense |  | $ | 921 |  |  | $ | 872 |  |  | $ | 803 |
Presented in the following table is CMS Energy’s and Consumers’ estimated amortization expense on intangible assets for each of the next five years:
In Millions |
| 2019 |  | 2020 |  | 2021 |  | 2022 |  | 2023 |
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |  |
Intangible asset amortization expense |  | $ | 132 |  |  | $ | 122 |  |  | $ | 108 |  |  | $ | 95 |  |  | $ | 74 |
Consumers |  |  |  |  |  |  |  |  |  |
Intangible asset amortization expense |  | $ | 130 |  |  | $ | 120 |  |  | $ | 106 |  |  | $ | 94 |  |  | $ | 74 |
Intangible Assets: Included in net plant, property, and equipment are intangible assets. Presented in the following table are details about CMS Energy’s and Consumers’ intangible assets:
In Millions |
|  | December 31, 2018 |  | December 31, 2017
Description | Amortization Life in Years | Gross Cost 1 |  | Accumulated Amortization |  |  | Gross Cost 1 |  | Accumulated Amortization |
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |
Software development | 1 | — | 15 |  | $ | 1,024 |  |  | $ | 603 |  |  |  | $ | 950 |  |  | $ | 481 |
Rights of way | 50 | — | 85 |  | 167 |  |  | 52 |  |  |  | 162 |  |  | 50 |
Franchises and consents | 5 | — | 30 |  | 15 |  |  | 9 |  |  |  | 14 |  |  | 8 |
Leasehold improvements | various 2 |  | 9 |  |  | 7 |  |  |  | 9 |  |  | 7 |
Other intangibles | various |  | 27 |  |  | 15 |  |  |  | 23 |  |  | 15 |
Total |  |  |  |  | $ | 1,242 |  |  | $ | 686 |  |  |  | $ | 1,158 |  |  | $ | 561 |
Consumers |  |  |  |  |  |  |  |  |  |  |  |
Software development | 3 | — | 15 |  | $ | 1,009 |  |  | $ | 595 |  |  |  | $ | 937 |  |  | $ | 475 |
Rights of way | 50 | — | 85 |  | 167 |  |  | 52 |  |  |  | 162 |  |  | 50 |
Franchises and consents | 5 | — | 30 |  | 15 |  |  | 9 |  |  |  | 14 |  |  | 8 |
Leasehold improvements | various 2 |  | 9 |  |  | 7 |  |  |  | 9 |  |  | 7 |
Other intangibles | various |  | 26 |  |  | 15 |  |  |  | 21 |  |  | 15 |
Total |  |  |  |  | $ | 1,226 |  |  | $ | 678 |  |  |  | $ | 1,143 |  |  | $ | 555 |
1 | For the year ended December 31, 2018, Consumers’ intangible asset additions were $90 million and intangible asset retirements were $7 million. For the year ended December 31, 2017, Consumers’ intangible asset additions were $100 million and there were no intangible asset retirements.
2 | Leasehold improvements are amortized over the life of the lease, which may change whenever the lease is renewed or extended.
Jointly Owned Regulated Utility Facilities Presented in the following table are Consumers’ investments in jointly owned regulated utility facilities at December 31, 2018:
In Millions, Except Ownership Share |
J.H. Campbell Unit 3 |  | Ludington |  |  | Other |
Ownership share |  | 93.3 | % |  | 51.0 | % |  | various |
Utility plant in service |  | $ | 1,688 |  |  | $ | 411 |  |  | $ | 226 |
Accumulated depreciation |  | (670 | ) |  | (155 | ) |  | (70 | )
Construction work in progress |  | 23 |  |  | 110 |  |  | 16 |
Net investment |  | $ | 1,041 |  |  | $ | 366 |  |  | $ | 172 |
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.

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