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Plant, Property, and Equipment (Tables) | 12 Months Ended
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Dec. 31, 2019
Public Utility, Property, Plant and Equipment [Line Items] |
Schedule Of Property, Plant 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 | 2019 |  | 2018 |
CMS Energy, including Consumers |  |  |  |  |  |  |
Plant, property, and equipment, gross |  |  |  |  |  |  |
Consumers | 3 | — | 125 |  | $ | 24,963 |  |  | $ | 23,963 |
Enterprises |  |  |  |  |  |  |
Independent power production 1 | 3 | — | 40 |  | 403 |  |  | 410 |
Other | 3 | — | 5 |  | 2 |  |  | 2 |
EnerBank | 1 | — | 7 |  | 22 |  |  | 25 |
Plant, property, and equipment, gross |  |  |  |  | $ | 25,390 |  |  | $ | 24,400 |
Construction work in progress |  |  |  |  | 896 |  |  | 763 |
Accumulated depreciation and amortization |  |  |  |  | (7,360 | ) |  | (7,037 | )
Total plant, property, and equipment |  |  |  |  | $ | 18,926 |  |  | $ | 18,126 |
Consumers |  |  |  |  |  |  |
Plant, property, and equipment, gross |  |  |  |  |  |  |
Electric |  |  |  |  |  |  |
Generation | 22 | — | 125 |  | $ | 5,942 |  |  | $ | 6,305 |
Distribution | 20 | — | 75 |  | 8,519 |  |  | 7,957 |
Transmission | 46 | — | 75 |  | 113 |  |  | 154 |
Other | 5 | — | 50 |  | 1,258 |  |  | 1,316 |
Assets under finance leases and other financing 2 |  |  |  |  | 326 |  |  | 295 |
Gas |  |  |  |  |  |  |
Distribution | 20 | — | 85 |  | 5,235 |  |  | 4,651 |
Transmission | 17 | — | 75 |  | 1,752 |  |  | 1,521 |
Underground storage facilities 3 | 27 | — | 75 |  | 987 |  |  | 910 |
Other | 5 | — | 50 |  | 797 |  |  | 823 |
Assets under finance leases 2 |  |  |  |  | 14 |  |  | 14 |
Other non‑utility property | 3 | — | 51 |  | 20 |  |  | 17 |
Plant, property, and equipment, gross |  |  |  |  | $ | 24,963 |  |  | $ | 23,963 |
Construction work in progress |  |  |  |  | 879 |  |  | 756 |
Accumulated depreciation and amortization |  |  |  |  | (7,272 | ) |  | (6,958 | )
Total plant, property, and equipment 4 |  |  |  |  | $ | 18,570 |  |  | $ | 17,761 |
1 | The majority 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 10, Leases and Palisades Financing.
2 | For information regarding the amortization terms of Consumers’ assets under finance leases and other financing, see Note 10, Leases and Palisades Financing.
3 | Underground storage includes base natural gas of $26 million at December 31, 2019 and 2018. Base natural gas is not subject to depreciation.
4 For the year ended December 31, 2019, Consumers’ plant additions were $2.0 billion and plant retirements were $380 million. For the year ended December 31, 2018, Consumers’ plant additions were $1.8 billion and plant retirements were $190 million. Consumers plans to retire the D.E. Karn 1 & 2 coal-fueled electric generating units in 2023. Accordingly, in 2019, Consumers removed from total plant, property, and equipment $667 million, representing the remaining book value of the two units upon their retirement, and recorded it as a regulatory asset. For additional details, see Note 3, Regulatory Matters.
Schedule of Finite-Lived Intangible Assets by Major Class Table | Presented in the following table are details about CMS Energy’s and Consumers’ intangible assets:
In Millions |
|  | December 31, 2019 |  | December 31, 2018
Description | Amortization Life in Years | Gross Cost¹ |  | Accumulated Amortization |  |  | Gross Cost¹ |  | Accumulated Amortization |
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |
Software development | 1 | — | 15 |  | $ | 882 |  |  | $ | 529 |  |  |  | $ | 1,024 |  |  | $ | 603 |
Rights of way | 50 | — | 85 |  | 180 |  |  | 55 |  |  |  | 167 |  |  | 52 |
Franchises and consents | 5 | — | 50 |  | 16 |  |  | 9 |  |  |  | 15 |  |  | 9 |
Leasehold improvements | various² |  | 9 |  |  | 7 |  |  |  | 9 |  |  | 7 |
Other intangibles | various |  | 27 |  |  | 15 |  |  |  | 27 |  |  | 15 |
Total |  |  |  |  | $ | 1,114 |  |  | $ | 615 |  |  |  | $ | 1,242 |  |  | $ | 686 |
Consumers |  |  |  |  |  |  |  |  |  |  |  |
Software development | 3 | — | 15 |  | $ | 869 |  |  | $ | 521 |  |  |  | $ | 1,009 |  |  | $ | 595 |
Rights of way | 50 | — | 85 |  | 180 |  |  | 55 |  |  |  | 167 |  |  | 52 |
Franchises and consents | 5 | — | 50 |  | 16 |  |  | 9 |  |  |  | 15 |  |  | 9 |
Leasehold improvements | various² |  | 9 |  |  | 7 |  |  |  | 9 |  |  | 7 |
Other intangibles | various |  | 26 |  |  | 15 |  |  |  | 26 |  |  | 15 |
Total |  |  |  |  | $ | 1,100 |  |  | $ | 607 |  |  |  | $ | 1,226 |  |  | $ | 678 |
1 | For the year ended December 31, 2019, Consumers’ intangible asset additions were $67 million and intangible asset retirements were $193 million. For the year ended December 31, 2018, Consumers’ intangible asset additions were $90 million and intangible asset retirements were $7 million.
2 Leasehold improvements are amortized over the life of the lease, which may change whenever the lease is renewed or extended.
Public Utilities Property Plant and Equipment Schedule of Accumulated Depreciation and Amortization Table | Presented in the following table are further details about CMS Energy’s and Consumers’ accumulated depreciation and amortization:
In Millions |
December 31 | 2019 |  | 2018 |
CMS Energy, including Consumers |  |  |  |
Utility plant assets |  | $ | 7,269 |  |  | $ | 6,956 |
Non‑utility plant assets |  | 91 |  |  | 81 |
Consumers |  |  |  |
Utility plant assets |  | $ | 7,269 |  |  | $ | 6,956 |
Non‑utility plant assets |  | 3 |  |  | 2 |
Schedule Of Depreciation And Amortization | Presented in the following table are the components of CMS Energy’s and Consumers’ depreciation and amortization expense:
In Millions |
Years Ended December 31 | 2019 |  | 2018 |  | 2017 |
CMS Energy, including Consumers |  |  |  |  |  |
Depreciation expense – plant, property, and equipment |  | $ | 842 |  |  | $ | 778 |  |  | $ | 739 |
Amortization expense |  |  |  |  |  |
Software |  | 121 |  |  | 127 |  |  | 114 |
Other intangible assets |  | 3 |  |  | 3 |  |  | 3 |
Securitized regulatory assets |  | 26 |  |  | 25 |  |  | 25 |
Total depreciation and amortization expense |  | $ | 992 |  |  | $ | 933 |  |  | $ | 881 |
Consumers |  |  |  |  |  |
Depreciation expense – plant, property, and equipment |  | $ | 827 |  |  | $ | 768 |  |  | $ | 732 |
Amortization expense |  |  |  |  |  |
Software |  | 119 |  |  | 125 |  |  | 112 |
Other intangible assets |  | 3 |  |  | 3 |  |  | 3 |
Securitized regulatory assets |  | 26 |  |  | 25 |  |  | 25 |
Total depreciation and amortization expense |  | $ | 975 |  |  | $ | 921 |  |  | $ | 872 |
Schedule Of Estimated Amortization Expense For Intangibles | 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 |
| 2020 |  | 2021 |  | 2022 |  | 2023 |  | 2024 |
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |  |
Intangible asset amortization expense |  | $ | 118 |  |  | $ | 112 |  |  | $ | 107 |  |  | $ | 87 |  |  | $ | 70 |
Consumers |  |  |  |  |  |  |  |  |  |
Intangible asset amortization expense |  | $ | 116 |  |  | $ | 110 |  |  | $ | 106 |  |  | $ | 87 |  |  | $ | 70 |
Consumers Energy Company |
Public Utility, Property, Plant and Equipment [Line Items] |
Schedule Of Property, Plant And Equipment | Assets Under Finance Leases and Other Financing: Presented in the following table are further details about changes in Consumers’ assets under finance leases and other financing:
In Millions |
Years Ended December 31 | 2019 |  | 2018 |
Consumers |  |  |  |
Balance at beginning of period |  | $ | 309 |  |  | $ | 312 |
Additions |  | 26 |  |  | — |
Net retirements and other adjustments |  | 5 |  |  | (3 | )
Balance at end of period |  | $ | 340 |  |  | $ | 309 |
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 | 2019 |  | 2018 |
CMS Energy, including Consumers |  |  |  |  |  |  |
Plant, property, and equipment, gross |  |  |  |  |  |  |
Consumers | 3 | — | 125 |  | $ | 24,963 |  |  | $ | 23,963 |
Enterprises |  |  |  |  |  |  |
Independent power production 1 | 3 | — | 40 |  | 403 |  |  | 410 |
Other | 3 | — | 5 |  | 2 |  |  | 2 |
EnerBank | 1 | — | 7 |  | 22 |  |  | 25 |
Plant, property, and equipment, gross |  |  |  |  | $ | 25,390 |  |  | $ | 24,400 |
Construction work in progress |  |  |  |  | 896 |  |  | 763 |
Accumulated depreciation and amortization |  |  |  |  | (7,360 | ) |  | (7,037 | )
Total plant, property, and equipment |  |  |  |  | $ | 18,926 |  |  | $ | 18,126 |
Consumers |  |  |  |  |  |  |
Plant, property, and equipment, gross |  |  |  |  |  |  |
Electric |  |  |  |  |  |  |
Generation | 22 | — | 125 |  | $ | 5,942 |  |  | $ | 6,305 |
Distribution | 20 | — | 75 |  | 8,519 |  |  | 7,957 |
Transmission | 46 | — | 75 |  | 113 |  |  | 154 |
Other | 5 | — | 50 |  | 1,258 |  |  | 1,316 |
Assets under finance leases and other financing 2 |  |  |  |  | 326 |  |  | 295 |
Gas |  |  |  |  |  |  |
Distribution | 20 | — | 85 |  | 5,235 |  |  | 4,651 |
Transmission | 17 | — | 75 |  | 1,752 |  |  | 1,521 |
Underground storage facilities 3 | 27 | — | 75 |  | 987 |  |  | 910 |
Other | 5 | — | 50 |  | 797 |  |  | 823 |
Assets under finance leases 2 |  |  |  |  | 14 |  |  | 14 |
Other non‑utility property | 3 | — | 51 |  | 20 |  |  | 17 |
Plant, property, and equipment, gross |  |  |  |  | $ | 24,963 |  |  | $ | 23,963 |
Construction work in progress |  |  |  |  | 879 |  |  | 756 |
Accumulated depreciation and amortization |  |  |  |  | (7,272 | ) |  | (6,958 | )
Total plant, property, and equipment 4 |  |  |  |  | $ | 18,570 |  |  | $ | 17,761 |
1 | The majority 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 10, Leases and Palisades Financing.
2 | For information regarding the amortization terms of Consumers’ assets under finance leases and other financing, see Note 10, Leases and Palisades Financing.
3 | Underground storage includes base natural gas of $26 million at December 31, 2019 and 2018. Base natural gas is not subject to depreciation.
4 For the year ended December 31, 2019, Consumers’ plant additions were $2.0 billion and plant retirements were $380 million. For the year ended December 31, 2018, Consumers’ plant additions were $1.8 billion and plant retirements were $190 million. Consumers plans to retire the D.E. Karn 1 & 2 coal-fueled electric generating units in 2023. Accordingly, in 2019, Consumers removed from total plant, property, and equipment $667 million, representing the remaining book value of the two units upon their retirement, and recorded it as a regulatory asset. For additional details, see Note 3, Regulatory Matters.
Schedule of Finite-Lived Intangible Assets by Major Class Table | Presented in the following table are details about CMS Energy’s and Consumers’ intangible assets:
In Millions |
|  | December 31, 2019 |  | December 31, 2018
Description | Amortization Life in Years | Gross Cost¹ |  | Accumulated Amortization |  |  | Gross Cost¹ |  | Accumulated Amortization |
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |
Software development | 1 | — | 15 |  | $ | 882 |  |  | $ | 529 |  |  |  | $ | 1,024 |  |  | $ | 603 |
Rights of way | 50 | — | 85 |  | 180 |  |  | 55 |  |  |  | 167 |  |  | 52 |
Franchises and consents | 5 | — | 50 |  | 16 |  |  | 9 |  |  |  | 15 |  |  | 9 |
Leasehold improvements | various² |  | 9 |  |  | 7 |  |  |  | 9 |  |  | 7 |
Other intangibles | various |  | 27 |  |  | 15 |  |  |  | 27 |  |  | 15 |
Total |  |  |  |  | $ | 1,114 |  |  | $ | 615 |  |  |  | $ | 1,242 |  |  | $ | 686 |
Consumers |  |  |  |  |  |  |  |  |  |  |  |
Software development | 3 | — | 15 |  | $ | 869 |  |  | $ | 521 |  |  |  | $ | 1,009 |  |  | $ | 595 |
Rights of way | 50 | — | 85 |  | 180 |  |  | 55 |  |  |  | 167 |  |  | 52 |
Franchises and consents | 5 | — | 50 |  | 16 |  |  | 9 |  |  |  | 15 |  |  | 9 |
Leasehold improvements | various² |  | 9 |  |  | 7 |  |  |  | 9 |  |  | 7 |
Other intangibles | various |  | 26 |  |  | 15 |  |  |  | 26 |  |  | 15 |
Total |  |  |  |  | $ | 1,100 |  |  | $ | 607 |  |  |  | $ | 1,226 |  |  | $ | 678 |
1 | For the year ended December 31, 2019, Consumers’ intangible asset additions were $67 million and intangible asset retirements were $193 million. For the year ended December 31, 2018, Consumers’ intangible asset additions were $90 million and intangible asset retirements were $7 million.
2 Leasehold improvements are amortized over the life of the lease, which may change whenever the lease is renewed or extended.
Public Utilities, Allowance For Funds Used During Construction Average Rate | Presented in the following table are Consumers’ average AFUDC capitalization rates:
Years Ended December 31 | 2019 |  | 2018 |  | 2017 |
Electric | 6.4 | % | 6.9 | % | 6.8 | %
Gas | 5.8 |  | 5.9 |  | 6.0 |
Public Utilities Property Plant and Equipment Schedule of Accumulated Depreciation and Amortization Table | Presented in the following table are further details about CMS Energy’s and Consumers’ accumulated depreciation and amortization:
In Millions |
December 31 | 2019 |  | 2018 |
CMS Energy, including Consumers |  |  |  |
Utility plant assets |  | $ | 7,269 |  |  | $ | 6,956 |
Non‑utility plant assets |  | 91 |  |  | 81 |
Consumers |  |  |  |
Utility plant assets |  | $ | 7,269 |  |  | $ | 6,956 |
Non‑utility plant assets |  | 3 |  |  | 2 |
Public Utilities Property Plant and Equipment Schedule of Composite Depreciation Rate Table | Presented in the following table are the composite depreciation rates for Consumers’ segment properties:
Years Ended December 31 | 2019 |  | 2018 |  | 2017 |
Electric utility property |  | 3.9 | % |  | 3.9 | % |  | 3.9 | %
Gas utility property |  | 2.9 |  |  | 2.9 |  |  | 2.9 |
Other property |  | 10.0 |  |  | 10.1 |  |  | 10.0 |
Schedule Of Depreciation And Amortization | Presented in the following table are the components of CMS Energy’s and Consumers’ depreciation and amortization expense:
In Millions |
Years Ended December 31 | 2019 |  | 2018 |  | 2017 |
CMS Energy, including Consumers |  |  |  |  |  |
Depreciation expense – plant, property, and equipment |  | $ | 842 |  |  | $ | 778 |  |  | $ | 739 |
Amortization expense |  |  |  |  |  |
Software |  | 121 |  |  | 127 |  |  | 114 |
Other intangible assets |  | 3 |  |  | 3 |  |  | 3 |
Securitized regulatory assets |  | 26 |  |  | 25 |  |  | 25 |
Total depreciation and amortization expense |  | $ | 992 |  |  | $ | 933 |  |  | $ | 881 |
Consumers |  |  |  |  |  |
Depreciation expense – plant, property, and equipment |  | $ | 827 |  |  | $ | 768 |  |  | $ | 732 |
Amortization expense |  |  |  |  |  |
Software |  | 119 |  |  | 125 |  |  | 112 |
Other intangible assets |  | 3 |  |  | 3 |  |  | 3 |
Securitized regulatory assets |  | 26 |  |  | 25 |  |  | 25 |
Total depreciation and amortization expense |  | $ | 975 |  |  | $ | 921 |  |  | $ | 872 |
Schedule Of Estimated Amortization Expense For Intangibles | 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 |
| 2020 |  | 2021 |  | 2022 |  | 2023 |  | 2024 |
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |  |
Intangible asset amortization expense |  | $ | 118 |  |  | $ | 112 |  |  | $ | 107 |  |  | $ | 87 |  |  | $ | 70 |
Consumers |  |  |  |  |  |  |  |  |  |
Intangible asset amortization expense |  | $ | 116 |  |  | $ | 110 |  |  | $ | 106 |  |  | $ | 87 |  |  | $ | 70 |
Jointly Owned Regulated Utility Facilities | Presented in the following table are Consumers’ investments in jointly owned regulated utility facilities at December 31, 2019:
In Millions, Except Ownership Share |
J.H. Campbell Unit 3 |  | Ludington |  |  | Other |
Ownership share |  | 93.3 | % |  | 51.0 | % |  | various |
Utility plant in service |  | $ | 1,731 |  |  | $ | 486 |  |  | $ | 233 |
Accumulated depreciation |  | (753 | ) |  | (166 | ) |  | (68 | )
Construction work in progress |  | 16 |  |  | 64 |  |  | 15 |
Net investment |  | $ | 994 |  |  | $ | 384 |  |  | $ | 180 |

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